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Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Browse Source 
Pull locking updates from Ingo Molnar:
 "The locking tree was busier in this cycle than the usual pattern - a
  couple of major projects happened to coincide.

  The main changes are:

   - implement the atomic_fetch_{add,sub,and,or,xor}() API natively
     across all SMP architectures (Peter Zijlstra)

   - add atomic_fetch_{inc/dec}() as well, using the generic primitives
     (Davidlohr Bueso)

   - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
     Waiman Long)

   - optimize smp_cond_load_acquire() on arm64 and implement LSE based
     atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
     on arm64 (Will Deacon)

   - introduce smp_acquire__after_ctrl_dep() and fix various barrier
     mis-uses and bugs (Peter Zijlstra)

   - after discovering ancient spin_unlock_wait() barrier bugs in its
     implementation and usage, strengthen its semantics and update/fix
     usage sites (Peter Zijlstra)

   - optimize mutex_trylock() fastpath (Peter Zijlstra)

   - ... misc fixes and cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
  locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
  locking/static_keys: Fix non static symbol Sparse warning
  locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
  locking/atomic, arch/tile: Fix tilepro build
  locking/atomic, arch/m68k: Remove comment
  locking/atomic, arch/arc: Fix build
  locking/Documentation: Clarify limited control-dependency scope
  locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
  locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
  locking/atomic, arch/mips: Convert to _relaxed atomics
  locking/atomic, arch/alpha: Convert to _relaxed atomics
  locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
  locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
  locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
  locking/atomic: Fix atomic64_relaxed() bits
  locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
  ...
This commit is contained in:
Linus Torvalds 2016-07-25 12:41:29 -07:00
commit c86ad14d30
108 changed files with 3341 additions and 1031 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
Documentation/memory-barriers.txt
View File

@ -806,6 +806,41 @@ out-guess your code. More generally, although READ_ONCE() does force
the compiler to actually emit code for a given load, it does not force
the compiler to use the results.
In addition, control dependencies apply only to the then-clause and
else-clause of the if-statement in question. In particular, it does
not necessarily apply to code following the if-statement:
q = READ_ONCE(a);
if (q) {
WRITE_ONCE(b, p);
} else {
WRITE_ONCE(b, r);
}
WRITE_ONCE(c, 1); /* BUG: No ordering against the read from "a". */
It is tempting to argue that there in fact is ordering because the
compiler cannot reorder volatile accesses and also cannot reorder
the writes to "b" with the condition. Unfortunately for this line
of reasoning, the compiler might compile the two writes to "b" as
conditional-move instructions, as in this fanciful pseudo-assembly
language:
ld r1,a
ld r2,p
ld r3,r
cmp r1,$0
cmov,ne r4,r2
cmov,eq r4,r3
st r4,b
st $1,c
A weakly ordered CPU would have no dependency of any sort between the load
from "a" and the store to "c". The control dependencies would extend
only to the pair of cmov instructions and the store depending on them.
In short, control dependencies apply only to the stores in the then-clause
and else-clause of the if-statement in question (including functions
invoked by those two clauses), not to code following that if-statement.
Finally, control dependencies do -not- provide transitivity. This is
demonstrated by two related examples, with the initial values of
x and y both being zero:
@ -869,6 +904,12 @@ In summary:
atomic{,64}_read() can help to preserve your control dependency.
Please see the COMPILER BARRIER section for more information.
(*) Control dependencies apply only to the then-clause and else-clause
of the if-statement containing the control dependency, including
any functions that these two clauses call. Control dependencies
do -not- apply to code following the if-statement containing the
control dependency.
(*) Control dependencies pair normally with other types of barriers.
(*) Control dependencies do -not- provide transitivity. If you

16
MAINTAINERS
View File

@ -7024,15 +7024,23 @@ Q: http://patchwork.linuxtv.org/project/linux-media/list/
S: Maintained
F: drivers/media/usb/dvb-usb-v2/lmedm04*
LOCKDEP AND LOCKSTAT
LOCKING PRIMITIVES
M: Peter Zijlstra <peterz@infradead.org>
M: Ingo Molnar <mingo@redhat.com>
L: linux-kernel@vger.kernel.org
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core/locking
T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking/core
S: Maintained
F: Documentation/locking/lockdep*.txt
F: Documentation/locking/lockstat.txt
F: Documentation/locking/
F: include/linux/lockdep.h
F: include/linux/spinlock*.h
F: arch/*/include/asm/spinlock*.h
F: include/linux/rwlock*.h
F: include/linux/mutex*.h
F: arch/*/include/asm/mutex*.h
F: include/linux/rwsem*.h
F: arch/*/include/asm/rwsem.h
F: include/linux/seqlock.h
F: lib/locking*.[ch]
F: kernel/locking/
LOGICAL DISK MANAGER SUPPORT (LDM, Windows 2000/XP/Vista Dynamic Disks)

87
arch/alpha/include/asm/atomic.h
View File

@ -46,10 +46,9 @@ static __inline__ void atomic_##op(int i, atomic_t * v) \
} \
#define ATOMIC_OP_RETURN(op, asm_op) \
static inline int atomic_##op##_return(int i, atomic_t *v) \
static inline int atomic_##op##_return_relaxed(int i, atomic_t *v) \
{ \
long temp, result; \
smp_mb(); \
__asm__ __volatile__( \
"1: ldl_l %0,%1\n" \
" " #asm_op " %0,%3,%2\n" \
@ -61,7 +60,23 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
smp_mb(); \
return result; \
}
#define ATOMIC_FETCH_OP(op, asm_op) \
static inline int atomic_fetch_##op##_relaxed(int i, atomic_t *v) \
{ \
long temp, result; \
__asm__ __volatile__( \
"1: ldl_l %2,%1\n" \
" " #asm_op " %2,%3,%0\n" \
" stl_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
return result; \
}
@ -82,10 +97,9 @@ static __inline__ void atomic64_##op(long i, atomic64_t * v) \
} \
#define ATOMIC64_OP_RETURN(op, asm_op) \
static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \
static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
{ \
long temp, result; \
smp_mb(); \
__asm__ __volatile__( \
"1: ldq_l %0,%1\n" \
" " #asm_op " %0,%3,%2\n" \
@ -97,34 +111,77 @@ static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
smp_mb(); \
return result; \
}
#define ATOMIC64_FETCH_OP(op, asm_op) \
static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v) \
{ \
long temp, result; \
__asm__ __volatile__( \
"1: ldq_l %2,%1\n" \
" " #asm_op " %2,%3,%0\n" \
" stq_c %0,%1\n" \
" beq %0,2f\n" \
".subsection 2\n" \
"2: br 1b\n" \
".previous" \
:"=&r" (temp), "=m" (v->counter), "=&r" (result) \
:"Ir" (i), "m" (v->counter) : "memory"); \
return result; \
}
#define ATOMIC_OPS(op) \
ATOMIC_OP(op, op##l) \
ATOMIC_OP_RETURN(op, op##l) \
ATOMIC_FETCH_OP(op, op##l) \
ATOMIC64_OP(op, op##q) \
ATOMIC64_OP_RETURN(op, op##q)
ATOMIC64_OP_RETURN(op, op##q) \
ATOMIC64_FETCH_OP(op, op##q)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#define atomic_andnot atomic_andnot
#define atomic64_andnot atomic64_andnot
ATOMIC_OP(and, and)
ATOMIC_OP(andnot, bic)
ATOMIC_OP(or, bis)
ATOMIC_OP(xor, xor)
ATOMIC64_OP(and, and)
ATOMIC64_OP(andnot, bic)
ATOMIC64_OP(or, bis)
ATOMIC64_OP(xor, xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, asm) \
ATOMIC_OP(op, asm) \
ATOMIC_FETCH_OP(op, asm) \
ATOMIC64_OP(op, asm) \
ATOMIC64_FETCH_OP(op, asm)
ATOMIC_OPS(and, and)
ATOMIC_OPS(andnot, bic)
ATOMIC_OPS(or, bis)
ATOMIC_OPS(xor, xor)
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_andnot_relaxed atomic_fetch_andnot_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_andnot_relaxed atomic64_fetch_andnot_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#undef ATOMIC_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

68
arch/alpha/include/asm/rwsem.h
View File

@ -25,8 +25,8 @@ static inline void __down_read(struct rw_semaphore *sem)
{
long oldcount;
#ifndef CONFIG_SMP
oldcount = sem->count;
sem->count += RWSEM_ACTIVE_READ_BIAS;
oldcount = sem->count.counter;
sem->count.counter += RWSEM_ACTIVE_READ_BIAS;
#else
long temp;
__asm__ __volatile__(
@ -52,13 +52,13 @@ static inline int __down_read_trylock(struct rw_semaphore *sem)
{
long old, new, res;
res = sem->count;
res = atomic_long_read(&sem->count);
do {
new = res + RWSEM_ACTIVE_READ_BIAS;
if (new <= 0)
break;
old = res;
res = cmpxchg(&sem->count, old, new);
res = atomic_long_cmpxchg(&sem->count, old, new);
} while (res != old);
return res >= 0 ? 1 : 0;
}
@ -67,8 +67,8 @@ static inline long ___down_write(struct rw_semaphore *sem)
{
long oldcount;
#ifndef CONFIG_SMP
oldcount = sem->count;
sem->count += RWSEM_ACTIVE_WRITE_BIAS;
oldcount = sem->count.counter;
sem->count.counter += RWSEM_ACTIVE_WRITE_BIAS;
#else
long temp;
__asm__ __volatile__(
@ -106,7 +106,7 @@ static inline int __down_write_killable(struct rw_semaphore *sem)
*/
static inline int __down_write_trylock(struct rw_semaphore *sem)
{
long ret = cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE,
long ret = atomic_long_cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE,
RWSEM_ACTIVE_WRITE_BIAS);
if (ret == RWSEM_UNLOCKED_VALUE)
return 1;
@ -117,8 +117,8 @@ static inline void __up_read(struct rw_semaphore *sem)
{
long oldcount;
#ifndef CONFIG_SMP
oldcount = sem->count;
sem->count -= RWSEM_ACTIVE_READ_BIAS;
oldcount = sem->count.counter;
sem->count.counter -= RWSEM_ACTIVE_READ_BIAS;
#else
long temp;
__asm__ __volatile__(
@ -142,8 +142,8 @@ static inline void __up_write(struct rw_semaphore *sem)
{
long count;
#ifndef CONFIG_SMP
sem->count -= RWSEM_ACTIVE_WRITE_BIAS;
count = sem->count;
sem->count.counter -= RWSEM_ACTIVE_WRITE_BIAS;
count = sem->count.counter;
#else
long temp;
__asm__ __volatile__(
@ -171,8 +171,8 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
{
long oldcount;
#ifndef CONFIG_SMP
oldcount = sem->count;
sem->count -= RWSEM_WAITING_BIAS;
oldcount = sem->count.counter;
sem->count.counter -= RWSEM_WAITING_BIAS;
#else
long temp;
__asm__ __volatile__(
@ -191,47 +191,5 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
rwsem_downgrade_wake(sem);
}
static inline void rwsem_atomic_add(long val, struct rw_semaphore *sem)
{
#ifndef CONFIG_SMP
sem->count += val;
#else
long temp;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" addq %0,%2,%0\n"
" stq_c %0,%1\n"
" beq %0,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (temp), "=m" (sem->count)
:"Ir" (val), "m" (sem->count));
#endif
}
static inline long rwsem_atomic_update(long val, struct rw_semaphore *sem)
{
#ifndef CONFIG_SMP
sem->count += val;
return sem->count;
#else
long ret, temp;
__asm__ __volatile__(
"1: ldq_l %0,%1\n"
" addq %0,%3,%2\n"
" addq %0,%3,%0\n"
" stq_c %2,%1\n"
" beq %2,2f\n"
".subsection 2\n"
"2: br 1b\n"
".previous"
:"=&r" (ret), "=m" (sem->count), "=&r" (temp)
:"Ir" (val), "m" (sem->count));
return ret;
#endif
}
#endif /* __KERNEL__ */
#endif /* _ALPHA_RWSEM_H */

9
arch/alpha/include/asm/spinlock.h
View File

@ -3,6 +3,8 @@
#include <linux/kernel.h>
#include <asm/current.h>
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* Simple spin lock operations. There are two variants, one clears IRQ's
@ -13,8 +15,11 @@
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_is_locked(x) ((x)->lock != 0)
#define arch_spin_unlock_wait(x) \
do { cpu_relax(); } while ((x)->lock)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, !VAL);
}
static inline int arch_spin_value_unlocked(arch_spinlock_t lock)
{

99
arch/arc/include/asm/atomic.h
View File

@ -67,6 +67,33 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return val; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned int val, orig; \
\
/* \
* Explicit full memory barrier needed before/after as \
* LLOCK/SCOND thmeselves don't provide any such semantics \
*/ \
smp_mb(); \
\
__asm__ __volatile__( \
"1: llock %[orig], [%[ctr]] \n" \
" " #asm_op " %[val], %[orig], %[i] \n" \
" scond %[val], [%[ctr]] \n" \
" \n" \
: [val] "=&r" (val), \
[orig] "=&r" (orig) \
: [ctr] "r" (&v->counter), \
[i] "ir" (i) \
: "cc"); \
\
smp_mb(); \
\
return orig; \
}
#else /* !CONFIG_ARC_HAS_LLSC */
#ifndef CONFIG_SMP
@ -129,25 +156,44 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
unsigned long orig; \
\
/* \
* spin lock/unlock provides the needed smp_mb() before/after \
*/ \
atomic_ops_lock(flags); \
orig = v->counter; \
v->counter c_op i; \
atomic_ops_unlock(flags); \
\
return orig; \
}
#endif /* !CONFIG_ARC_HAS_LLSC */
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
#define atomic_andnot atomic_andnot
ATOMIC_OP(and, &=, and)
ATOMIC_OP(andnot, &= ~, bic)
ATOMIC_OP(or, |=, or)
ATOMIC_OP(xor, ^=, xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
#undef SCOND_FAIL_RETRY_VAR_DEF
#undef SCOND_FAIL_RETRY_ASM
#undef SCOND_FAIL_RETRY_VARS
ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(andnot, &= ~, bic)
ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, xor)
#else /* CONFIG_ARC_PLAT_EZNPS */
@ -208,22 +254,51 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned int temp = i; \
\
/* Explicit full memory barrier needed before/after */ \
smp_mb(); \
\
__asm__ __volatile__( \
" mov r2, %0\n" \
" mov r3, %1\n" \
" .word %2\n" \
" mov %0, r2" \
: "+r"(temp) \
: "r"(&v->counter), "i"(asm_op) \
: "r2", "r3", "memory"); \
\
smp_mb(); \
\
return temp; \
}
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, CTOP_INST_AADD_DI_R2_R2_R3)
#define atomic_sub(i, v) atomic_add(-(i), (v))
#define atomic_sub_return(i, v) atomic_add_return(-(i), (v))
ATOMIC_OP(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(and, &=, CTOP_INST_AAND_DI_R2_R2_R3)
#define atomic_andnot(mask, v) atomic_and(~(mask), (v))
ATOMIC_OP(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
ATOMIC_OP(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
ATOMIC_OPS(or, |=, CTOP_INST_AOR_DI_R2_R2_R3)
ATOMIC_OPS(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3)
#endif /* CONFIG_ARC_PLAT_EZNPS */
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

7
arch/arc/include/asm/spinlock.h
View File

@ -15,8 +15,11 @@
#define arch_spin_is_locked(x) ((x)->slock != __ARCH_SPIN_LOCK_UNLOCKED__)
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_unlock_wait(x) \
do { while (arch_spin_is_locked(x)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->slock, !VAL);
}
#ifdef CONFIG_ARC_HAS_LLSC

106
arch/arm/include/asm/atomic.h
View File

@ -77,8 +77,36 @@ static inline int atomic_##op##_return_relaxed(int i, atomic_t *v) \
return result; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op##_relaxed(int i, atomic_t *v) \
{ \
unsigned long tmp; \
int result, val; \
\
prefetchw(&v->counter); \
\
__asm__ __volatile__("@ atomic_fetch_" #op "\n" \
"1: ldrex %0, [%4]\n" \
" " #asm_op " %1, %0, %5\n" \
" strex %2, %1, [%4]\n" \
" teq %2, #0\n" \
" bne 1b" \
: "=&r" (result), "=&r" (val), "=&r" (tmp), "+Qo" (v->counter) \
: "r" (&v->counter), "Ir" (i) \
: "cc"); \
\
return result; \
}
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_andnot_relaxed atomic_fetch_andnot_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
static inline int atomic_cmpxchg_relaxed(atomic_t *ptr, int old, int new)
{
@ -159,6 +187,20 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return val; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
int val; \
\
raw_local_irq_save(flags); \
val = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
\
return val; \
}
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
@ -187,19 +229,26 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
#define atomic_andnot atomic_andnot
ATOMIC_OP(and, &=, and)
ATOMIC_OP(andnot, &= ~, bic)
ATOMIC_OP(or, |=, orr)
ATOMIC_OP(xor, ^=, eor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(andnot, &= ~, bic)
ATOMIC_OPS(or, |=, orr)
ATOMIC_OPS(xor, ^=, eor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
@ -317,24 +366,61 @@ atomic64_##op##_return_relaxed(long long i, atomic64_t *v) \
return result; \
}
#define ATOMIC64_FETCH_OP(op, op1, op2) \
static inline long long \
atomic64_fetch_##op##_relaxed(long long i, atomic64_t *v) \
{ \
long long result, val; \
unsigned long tmp; \
\
prefetchw(&v->counter); \
\
__asm__ __volatile__("@ atomic64_fetch_" #op "\n" \
"1: ldrexd %0, %H0, [%4]\n" \
" " #op1 " %Q1, %Q0, %Q5\n" \
" " #op2 " %R1, %R0, %R5\n" \
" strexd %2, %1, %H1, [%4]\n" \
" teq %2, #0\n" \
" bne 1b" \
: "=&r" (result), "=&r" (val), "=&r" (tmp), "+Qo" (v->counter) \
: "r" (&v->counter), "r" (i) \
: "cc"); \
\
return result; \
}
#define ATOMIC64_OPS(op, op1, op2) \
ATOMIC64_OP(op, op1, op2) \
ATOMIC64_OP_RETURN(op, op1, op2)
ATOMIC64_OP_RETURN(op, op1, op2) \
ATOMIC64_FETCH_OP(op, op1, op2)
ATOMIC64_OPS(add, adds, adc)
ATOMIC64_OPS(sub, subs, sbc)
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, op1, op2) \
ATOMIC64_OP(op, op1, op2) \
ATOMIC64_FETCH_OP(op, op1, op2)
#define atomic64_andnot atomic64_andnot
ATOMIC64_OP(and, and, and)
ATOMIC64_OP(andnot, bic, bic)
ATOMIC64_OP(or, orr, orr)
ATOMIC64_OP(xor, eor, eor)
ATOMIC64_OPS(and, and, and)
ATOMIC64_OPS(andnot, bic, bic)
ATOMIC64_OPS(or, orr, orr)
ATOMIC64_OPS(xor, eor, eor)
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_andnot_relaxed atomic64_fetch_andnot_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

19
arch/arm/include/asm/spinlock.h
View File

@ -6,6 +6,8 @@
#endif
#include <linux/prefetch.h>
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* sev and wfe are ARMv6K extensions. Uniprocessor ARMv6 may not have the K
@ -50,8 +52,21 @@ static inline void dsb_sev(void)
* memory.
*/
#define arch_spin_unlock_wait(lock) \
do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
u16 owner = READ_ONCE(lock->tickets.owner);
for (;;) {
arch_spinlock_t tmp = READ_ONCE(*lock);
if (tmp.tickets.owner == tmp.tickets.next ||
tmp.tickets.owner != owner)
break;
wfe();
}
smp_acquire__after_ctrl_dep();
}
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)

60
arch/arm64/include/asm/atomic.h
View File

@ -76,6 +76,36 @@
#define atomic_dec_return_release(v) atomic_sub_return_release(1, (v))
#define atomic_dec_return(v) atomic_sub_return(1, (v))
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_add_acquire atomic_fetch_add_acquire
#define atomic_fetch_add_release atomic_fetch_add_release
#define atomic_fetch_add atomic_fetch_add
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#define atomic_fetch_sub_acquire atomic_fetch_sub_acquire
#define atomic_fetch_sub_release atomic_fetch_sub_release
#define atomic_fetch_sub atomic_fetch_sub
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_and_acquire atomic_fetch_and_acquire
#define atomic_fetch_and_release atomic_fetch_and_release
#define atomic_fetch_and atomic_fetch_and
#define atomic_fetch_andnot_relaxed atomic_fetch_andnot_relaxed
#define atomic_fetch_andnot_acquire atomic_fetch_andnot_acquire
#define atomic_fetch_andnot_release atomic_fetch_andnot_release
#define atomic_fetch_andnot atomic_fetch_andnot
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_or_acquire atomic_fetch_or_acquire
#define atomic_fetch_or_release atomic_fetch_or_release
#define atomic_fetch_or atomic_fetch_or
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
#define atomic_fetch_xor_acquire atomic_fetch_xor_acquire
#define atomic_fetch_xor_release atomic_fetch_xor_release
#define atomic_fetch_xor atomic_fetch_xor
#define atomic_xchg_relaxed(v, new) xchg_relaxed(&((v)->counter), (new))
#define atomic_xchg_acquire(v, new) xchg_acquire(&((v)->counter), (new))
#define atomic_xchg_release(v, new) xchg_release(&((v)->counter), (new))
@ -125,6 +155,36 @@
#define atomic64_dec_return_release(v) atomic64_sub_return_release(1, (v))
#define atomic64_dec_return(v) atomic64_sub_return(1, (v))
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_add_acquire atomic64_fetch_add_acquire
#define atomic64_fetch_add_release atomic64_fetch_add_release
#define atomic64_fetch_add atomic64_fetch_add
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#define atomic64_fetch_sub_acquire atomic64_fetch_sub_acquire
#define atomic64_fetch_sub_release atomic64_fetch_sub_release
#define atomic64_fetch_sub atomic64_fetch_sub
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_and_acquire atomic64_fetch_and_acquire
#define atomic64_fetch_and_release atomic64_fetch_and_release
#define atomic64_fetch_and atomic64_fetch_and
#define atomic64_fetch_andnot_relaxed atomic64_fetch_andnot_relaxed
#define atomic64_fetch_andnot_acquire atomic64_fetch_andnot_acquire
#define atomic64_fetch_andnot_release atomic64_fetch_andnot_release
#define atomic64_fetch_andnot atomic64_fetch_andnot
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_or_acquire atomic64_fetch_or_acquire
#define atomic64_fetch_or_release atomic64_fetch_or_release
#define atomic64_fetch_or atomic64_fetch_or
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#define atomic64_fetch_xor_acquire atomic64_fetch_xor_acquire
#define atomic64_fetch_xor_release atomic64_fetch_xor_release
#define atomic64_fetch_xor atomic64_fetch_xor
#define atomic64_xchg_relaxed atomic_xchg_relaxed
#define atomic64_xchg_acquire atomic_xchg_acquire
#define atomic64_xchg_release atomic_xchg_release

114
arch/arm64/include/asm/atomic_ll_sc.h
View File

@ -77,26 +77,57 @@ __LL_SC_PREFIX(atomic_##op##_return##name(int i, atomic_t *v)) \
} \
__LL_SC_EXPORT(atomic_##op##_return##name);
#define ATOMIC_FETCH_OP(name, mb, acq, rel, cl, op, asm_op) \
__LL_SC_INLINE int \
__LL_SC_PREFIX(atomic_fetch_##op##name(int i, atomic_t *v)) \
{ \
unsigned long tmp; \
int val, result; \
\
asm volatile("// atomic_fetch_" #op #name "\n" \
" prfm pstl1strm, %3\n" \
"1: ld" #acq "xr %w0, %3\n" \
" " #asm_op " %w1, %w0, %w4\n" \
" st" #rel "xr %w2, %w1, %3\n" \
" cbnz %w2, 1b\n" \
" " #mb \
: "=&r" (result), "=&r" (val), "=&r" (tmp), "+Q" (v->counter) \
: "Ir" (i) \
: cl); \
\
return result; \
} \
__LL_SC_EXPORT(atomic_fetch_##op##name);
#define ATOMIC_OPS(...) \
ATOMIC_OP(__VA_ARGS__) \
ATOMIC_OP_RETURN( , dmb ish, , l, "memory", __VA_ARGS__)
#define ATOMIC_OPS_RLX(...) \
ATOMIC_OPS(__VA_ARGS__) \
ATOMIC_OP_RETURN( , dmb ish, , l, "memory", __VA_ARGS__)\
ATOMIC_OP_RETURN(_relaxed, , , , , __VA_ARGS__)\
ATOMIC_OP_RETURN(_acquire, , a, , "memory", __VA_ARGS__)\
ATOMIC_OP_RETURN(_release, , , l, "memory", __VA_ARGS__)
ATOMIC_OP_RETURN(_release, , , l, "memory", __VA_ARGS__)\
ATOMIC_FETCH_OP ( , dmb ish, , l, "memory", __VA_ARGS__)\
ATOMIC_FETCH_OP (_relaxed, , , , , __VA_ARGS__)\
ATOMIC_FETCH_OP (_acquire, , a, , "memory", __VA_ARGS__)\
ATOMIC_FETCH_OP (_release, , , l, "memory", __VA_ARGS__)
ATOMIC_OPS_RLX(add, add)
ATOMIC_OPS_RLX(sub, sub)
ATOMIC_OPS(add, add)
ATOMIC_OPS(sub, sub)
ATOMIC_OP(and, and)
ATOMIC_OP(andnot, bic)
ATOMIC_OP(or, orr)
ATOMIC_OP(xor, eor)
#undef ATOMIC_OPS_RLX
#undef ATOMIC_OPS
#define ATOMIC_OPS(...) \
ATOMIC_OP(__VA_ARGS__) \
ATOMIC_FETCH_OP ( , dmb ish, , l, "memory", __VA_ARGS__)\
ATOMIC_FETCH_OP (_relaxed, , , , , __VA_ARGS__)\
ATOMIC_FETCH_OP (_acquire, , a, , "memory", __VA_ARGS__)\
ATOMIC_FETCH_OP (_release, , , l, "memory", __VA_ARGS__)
ATOMIC_OPS(and, and)
ATOMIC_OPS(andnot, bic)
ATOMIC_OPS(or, orr)
ATOMIC_OPS(xor, eor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
@ -140,26 +171,57 @@ __LL_SC_PREFIX(atomic64_##op##_return##name(long i, atomic64_t *v)) \
} \
__LL_SC_EXPORT(atomic64_##op##_return##name);
#define ATOMIC64_FETCH_OP(name, mb, acq, rel, cl, op, asm_op) \
__LL_SC_INLINE long \
__LL_SC_PREFIX(atomic64_fetch_##op##name(long i, atomic64_t *v)) \
{ \
long result, val; \
unsigned long tmp; \
\
asm volatile("// atomic64_fetch_" #op #name "\n" \
" prfm pstl1strm, %3\n" \
"1: ld" #acq "xr %0, %3\n" \
" " #asm_op " %1, %0, %4\n" \
" st" #rel "xr %w2, %1, %3\n" \
" cbnz %w2, 1b\n" \
" " #mb \
: "=&r" (result), "=&r" (val), "=&r" (tmp), "+Q" (v->counter) \
: "Ir" (i) \
: cl); \
\
return result; \
} \
__LL_SC_EXPORT(atomic64_fetch_##op##name);
#define ATOMIC64_OPS(...) \
ATOMIC64_OP(__VA_ARGS__) \
ATOMIC64_OP_RETURN(, dmb ish, , l, "memory", __VA_ARGS__)
#define ATOMIC64_OPS_RLX(...) \
ATOMIC64_OPS(__VA_ARGS__) \
ATOMIC64_OP_RETURN(, dmb ish, , l, "memory", __VA_ARGS__) \
ATOMIC64_OP_RETURN(_relaxed,, , , , __VA_ARGS__) \
ATOMIC64_OP_RETURN(_acquire,, a, , "memory", __VA_ARGS__) \
ATOMIC64_OP_RETURN(_release,, , l, "memory", __VA_ARGS__)
ATOMIC64_OP_RETURN(_release,, , l, "memory", __VA_ARGS__) \
ATOMIC64_FETCH_OP (, dmb ish, , l, "memory", __VA_ARGS__) \
ATOMIC64_FETCH_OP (_relaxed,, , , , __VA_ARGS__) \
ATOMIC64_FETCH_OP (_acquire,, a, , "memory", __VA_ARGS__) \
ATOMIC64_FETCH_OP (_release,, , l, "memory", __VA_ARGS__)
ATOMIC64_OPS_RLX(add, add)
ATOMIC64_OPS_RLX(sub, sub)
ATOMIC64_OPS(add, add)
ATOMIC64_OPS(sub, sub)
ATOMIC64_OP(and, and)
ATOMIC64_OP(andnot, bic)
ATOMIC64_OP(or, orr)
ATOMIC64_OP(xor, eor)
#undef ATOMIC64_OPS_RLX
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(...) \
ATOMIC64_OP(__VA_ARGS__) \
ATOMIC64_FETCH_OP (, dmb ish, , l, "memory", __VA_ARGS__) \
ATOMIC64_FETCH_OP (_relaxed,, , , , __VA_ARGS__) \
ATOMIC64_FETCH_OP (_acquire,, a, , "memory", __VA_ARGS__) \
ATOMIC64_FETCH_OP (_release,, , l, "memory", __VA_ARGS__)
ATOMIC64_OPS(and, and)
ATOMIC64_OPS(andnot, bic)
ATOMIC64_OPS(or, orr)
ATOMIC64_OPS(xor, eor)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

278
arch/arm64/include/asm/atomic_lse.h
View File

@ -26,54 +26,57 @@
#endif
#define __LL_SC_ATOMIC(op) __LL_SC_CALL(atomic_##op)
static inline void atomic_andnot(int i, atomic_t *v)
{
register int w0 asm ("w0") = i;
register atomic_t *x1 asm ("x1") = v;
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC(andnot),
" stclr %w[i], %[v]\n")
: [i] "+r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
#define ATOMIC_OP(op, asm_op) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
register int w0 asm ("w0") = i; \
register atomic_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC(op), \
" " #asm_op " %w[i], %[v]\n") \
: [i] "+r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS); \
}
static inline void atomic_or(int i, atomic_t *v)
{
register int w0 asm ("w0") = i;
register atomic_t *x1 asm ("x1") = v;
ATOMIC_OP(andnot, stclr)
ATOMIC_OP(or, stset)
ATOMIC_OP(xor, steor)
ATOMIC_OP(add, stadd)
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC(or),
" stset %w[i], %[v]\n")
: [i] "+r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
#undef ATOMIC_OP
#define ATOMIC_FETCH_OP(name, mb, op, asm_op, cl...) \
static inline int atomic_fetch_##op##name(int i, atomic_t *v) \
{ \
register int w0 asm ("w0") = i; \
register atomic_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
__LL_SC_ATOMIC(fetch_##op##name), \
/* LSE atomics */ \
" " #asm_op #mb " %w[i], %w[i], %[v]") \
: [i] "+r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return w0; \
}
static inline void atomic_xor(int i, atomic_t *v)
{
register int w0 asm ("w0") = i;
register atomic_t *x1 asm ("x1") = v;
#define ATOMIC_FETCH_OPS(op, asm_op) \
ATOMIC_FETCH_OP(_relaxed, , op, asm_op) \
ATOMIC_FETCH_OP(_acquire, a, op, asm_op, "memory") \
ATOMIC_FETCH_OP(_release, l, op, asm_op, "memory") \
ATOMIC_FETCH_OP( , al, op, asm_op, "memory")
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC(xor),
" steor %w[i], %[v]\n")
: [i] "+r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
ATOMIC_FETCH_OPS(andnot, ldclr)
ATOMIC_FETCH_OPS(or, ldset)
ATOMIC_FETCH_OPS(xor, ldeor)
ATOMIC_FETCH_OPS(add, ldadd)
static inline void atomic_add(int i, atomic_t *v)
{
register int w0 asm ("w0") = i;
register atomic_t *x1 asm ("x1") = v;
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC(add),
" stadd %w[i], %[v]\n")
: [i] "+r" (w0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
#undef ATOMIC_FETCH_OP
#undef ATOMIC_FETCH_OPS
#define ATOMIC_OP_ADD_RETURN(name, mb, cl...) \
static inline int atomic_add_return##name(int i, atomic_t *v) \
@ -119,6 +122,33 @@ static inline void atomic_and(int i, atomic_t *v)
: __LL_SC_CLOBBERS);
}
#define ATOMIC_FETCH_OP_AND(name, mb, cl...) \
static inline int atomic_fetch_and##name(int i, atomic_t *v) \
{ \
register int w0 asm ("w0") = i; \
register atomic_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
" nop\n" \
__LL_SC_ATOMIC(fetch_and##name), \
/* LSE atomics */ \
" mvn %w[i], %w[i]\n" \
" ldclr" #mb " %w[i], %w[i], %[v]") \
: [i] "+r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return w0; \
}
ATOMIC_FETCH_OP_AND(_relaxed, )
ATOMIC_FETCH_OP_AND(_acquire, a, "memory")
ATOMIC_FETCH_OP_AND(_release, l, "memory")
ATOMIC_FETCH_OP_AND( , al, "memory")
#undef ATOMIC_FETCH_OP_AND
static inline void atomic_sub(int i, atomic_t *v)
{
register int w0 asm ("w0") = i;
@ -164,57 +194,87 @@ ATOMIC_OP_SUB_RETURN(_release, l, "memory")
ATOMIC_OP_SUB_RETURN( , al, "memory")
#undef ATOMIC_OP_SUB_RETURN
#define ATOMIC_FETCH_OP_SUB(name, mb, cl...) \
static inline int atomic_fetch_sub##name(int i, atomic_t *v) \
{ \
register int w0 asm ("w0") = i; \
register atomic_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
" nop\n" \
__LL_SC_ATOMIC(fetch_sub##name), \
/* LSE atomics */ \
" neg %w[i], %w[i]\n" \
" ldadd" #mb " %w[i], %w[i], %[v]") \
: [i] "+r" (w0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return w0; \
}
ATOMIC_FETCH_OP_SUB(_relaxed, )
ATOMIC_FETCH_OP_SUB(_acquire, a, "memory")
ATOMIC_FETCH_OP_SUB(_release, l, "memory")
ATOMIC_FETCH_OP_SUB( , al, "memory")
#undef ATOMIC_FETCH_OP_SUB
#undef __LL_SC_ATOMIC
#define __LL_SC_ATOMIC64(op) __LL_SC_CALL(atomic64_##op)
static inline void atomic64_andnot(long i, atomic64_t *v)
{
register long x0 asm ("x0") = i;
register atomic64_t *x1 asm ("x1") = v;
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC64(andnot),
" stclr %[i], %[v]\n")
: [i] "+r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
#define ATOMIC64_OP(op, asm_op) \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
register long x0 asm ("x0") = i; \
register atomic64_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC64(op), \
" " #asm_op " %[i], %[v]\n") \
: [i] "+r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS); \
}
static inline void atomic64_or(long i, atomic64_t *v)
{
register long x0 asm ("x0") = i;
register atomic64_t *x1 asm ("x1") = v;
ATOMIC64_OP(andnot, stclr)
ATOMIC64_OP(or, stset)
ATOMIC64_OP(xor, steor)
ATOMIC64_OP(add, stadd)
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC64(or),
" stset %[i], %[v]\n")
: [i] "+r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
#undef ATOMIC64_OP
#define ATOMIC64_FETCH_OP(name, mb, op, asm_op, cl...) \
static inline long atomic64_fetch_##op##name(long i, atomic64_t *v) \
{ \
register long x0 asm ("x0") = i; \
register atomic64_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
__LL_SC_ATOMIC64(fetch_##op##name), \
/* LSE atomics */ \
" " #asm_op #mb " %[i], %[i], %[v]") \
: [i] "+r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return x0; \
}
static inline void atomic64_xor(long i, atomic64_t *v)
{
register long x0 asm ("x0") = i;
register atomic64_t *x1 asm ("x1") = v;
#define ATOMIC64_FETCH_OPS(op, asm_op) \
ATOMIC64_FETCH_OP(_relaxed, , op, asm_op) \
ATOMIC64_FETCH_OP(_acquire, a, op, asm_op, "memory") \
ATOMIC64_FETCH_OP(_release, l, op, asm_op, "memory") \
ATOMIC64_FETCH_OP( , al, op, asm_op, "memory")
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC64(xor),
" steor %[i], %[v]\n")
: [i] "+r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
ATOMIC64_FETCH_OPS(andnot, ldclr)
ATOMIC64_FETCH_OPS(or, ldset)
ATOMIC64_FETCH_OPS(xor, ldeor)
ATOMIC64_FETCH_OPS(add, ldadd)
static inline void atomic64_add(long i, atomic64_t *v)
{
register long x0 asm ("x0") = i;
register atomic64_t *x1 asm ("x1") = v;
asm volatile(ARM64_LSE_ATOMIC_INSN(__LL_SC_ATOMIC64(add),
" stadd %[i], %[v]\n")
: [i] "+r" (x0), [v] "+Q" (v->counter)
: "r" (x1)
: __LL_SC_CLOBBERS);
}
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_FETCH_OPS
#define ATOMIC64_OP_ADD_RETURN(name, mb, cl...) \
static inline long atomic64_add_return##name(long i, atomic64_t *v) \
@ -260,6 +320,33 @@ static inline void atomic64_and(long i, atomic64_t *v)
: __LL_SC_CLOBBERS);
}
#define ATOMIC64_FETCH_OP_AND(name, mb, cl...) \
static inline long atomic64_fetch_and##name(long i, atomic64_t *v) \
{ \
register long x0 asm ("w0") = i; \
register atomic64_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
" nop\n" \
__LL_SC_ATOMIC64(fetch_and##name), \
/* LSE atomics */ \
" mvn %[i], %[i]\n" \
" ldclr" #mb " %[i], %[i], %[v]") \
: [i] "+r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return x0; \
}
ATOMIC64_FETCH_OP_AND(_relaxed, )
ATOMIC64_FETCH_OP_AND(_acquire, a, "memory")
ATOMIC64_FETCH_OP_AND(_release, l, "memory")
ATOMIC64_FETCH_OP_AND( , al, "memory")
#undef ATOMIC64_FETCH_OP_AND
static inline void atomic64_sub(long i, atomic64_t *v)
{
register long x0 asm ("x0") = i;
@ -306,6 +393,33 @@ ATOMIC64_OP_SUB_RETURN( , al, "memory")
#undef ATOMIC64_OP_SUB_RETURN
#define ATOMIC64_FETCH_OP_SUB(name, mb, cl...) \
static inline long atomic64_fetch_sub##name(long i, atomic64_t *v) \
{ \
register long x0 asm ("w0") = i; \
register atomic64_t *x1 asm ("x1") = v; \
\
asm volatile(ARM64_LSE_ATOMIC_INSN( \
/* LL/SC */ \
" nop\n" \
__LL_SC_ATOMIC64(fetch_sub##name), \
/* LSE atomics */ \
" neg %[i], %[i]\n" \
" ldadd" #mb " %[i], %[i], %[v]") \
: [i] "+r" (x0), [v] "+Q" (v->counter) \
: "r" (x1) \
: __LL_SC_CLOBBERS, ##cl); \
\
return x0; \
}
ATOMIC64_FETCH_OP_SUB(_relaxed, )
ATOMIC64_FETCH_OP_SUB(_acquire, a, "memory")
ATOMIC64_FETCH_OP_SUB(_release, l, "memory")
ATOMIC64_FETCH_OP_SUB( , al, "memory")
#undef ATOMIC64_FETCH_OP_SUB
static inline long atomic64_dec_if_positive(atomic64_t *v)
{
register long x0 asm ("x0") = (long)v;

13
arch/arm64/include/asm/barrier.h
View File

@ -91,6 +91,19 @@ do { \
__u.__val; \
})
#define smp_cond_load_acquire(ptr, cond_expr) \
({ \
typeof(ptr) __PTR = (ptr); \
typeof(*ptr) VAL; \
for (;;) { \
VAL = smp_load_acquire(__PTR); \
if (cond_expr) \
break; \
__cmpwait_relaxed(__PTR, VAL); \
} \
VAL; \
})
#include <asm-generic/barrier.h>
#endif /* __ASSEMBLY__ */

51
arch/arm64/include/asm/cmpxchg.h
View File

@ -224,4 +224,55 @@ __CMPXCHG_GEN(_mb)
__ret; \
})
#define __CMPWAIT_CASE(w, sz, name) \
static inline void __cmpwait_case_##name(volatile void *ptr, \
unsigned long val) \
{ \
unsigned long tmp; \
\
asm volatile( \
" ldxr" #sz "\t%" #w "[tmp], %[v]\n" \
" eor %" #w "[tmp], %" #w "[tmp], %" #w "[val]\n" \
" cbnz %" #w "[tmp], 1f\n" \
" wfe\n" \
"1:" \
: [tmp] "=&r" (tmp), [v] "+Q" (*(unsigned long *)ptr) \
: [val] "r" (val)); \
}
__CMPWAIT_CASE(w, b, 1);
__CMPWAIT_CASE(w, h, 2);
__CMPWAIT_CASE(w, , 4);
__CMPWAIT_CASE( , , 8);
#undef __CMPWAIT_CASE
#define __CMPWAIT_GEN(sfx) \
static inline void __cmpwait##sfx(volatile void *ptr, \
unsigned long val, \
int size) \
{ \
switch (size) { \
case 1: \
return __cmpwait_case##sfx##_1(ptr, (u8)val); \
case 2: \
return __cmpwait_case##sfx##_2(ptr, (u16)val); \
case 4: \
return __cmpwait_case##sfx##_4(ptr, val); \
case 8: \
return __cmpwait_case##sfx##_8(ptr, val); \
default: \
BUILD_BUG(); \
} \
\
unreachable(); \
}
__CMPWAIT_GEN()
#undef __CMPWAIT_GEN
#define __cmpwait_relaxed(ptr, val) \
__cmpwait((ptr), (unsigned long)(val), sizeof(*(ptr)))
#endif /* __ASM_CMPXCHG_H */

54
arch/avr32/include/asm/atomic.h
View File

@ -41,21 +41,49 @@ static inline int __atomic_##op##_return(int i, atomic_t *v) \
return result; \
}
#define ATOMIC_FETCH_OP(op, asm_op, asm_con) \
static inline int __atomic_fetch_##op(int i, atomic_t *v) \
{ \
int result, val; \
\
asm volatile( \
"/* atomic_fetch_" #op " */\n" \
"1: ssrf 5\n" \
" ld.w %0, %3\n" \
" mov %1, %0\n" \
" " #asm_op " %1, %4\n" \
" stcond %2, %1\n" \
" brne 1b" \
: "=&r" (result), "=&r" (val), "=o" (v->counter) \
: "m" (v->counter), #asm_con (i) \
: "cc"); \
\
return result; \
}
ATOMIC_OP_RETURN(sub, sub, rKs21)
ATOMIC_OP_RETURN(add, add, r)
ATOMIC_FETCH_OP (sub, sub, rKs21)
ATOMIC_FETCH_OP (add, add, r)
#define ATOMIC_OP(op, asm_op) \
#define ATOMIC_OPS(op, asm_op) \
ATOMIC_OP_RETURN(op, asm_op, r) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
(void)__atomic_##op##_return(i, v); \
} \
ATOMIC_FETCH_OP(op, asm_op, r) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
return __atomic_fetch_##op(i, v); \
}
ATOMIC_OP(and, and)
ATOMIC_OP(or, or)
ATOMIC_OP(xor, eor)
ATOMIC_OPS(and, and)
ATOMIC_OPS(or, or)
ATOMIC_OPS(xor, eor)
#undef ATOMIC_OP
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
/*
@ -87,6 +115,14 @@ static inline int atomic_add_return(int i, atomic_t *v)
return __atomic_add_return(i, v);
}
static inline int atomic_fetch_add(int i, atomic_t *v)
{
if (IS_21BIT_CONST(i))
return __atomic_fetch_sub(-i, v);
return __atomic_fetch_add(i, v);
}
/*
* atomic_sub_return - subtract the atomic variable
* @i: integer value to subtract
@ -102,6 +138,14 @@ static inline int atomic_sub_return(int i, atomic_t *v)
return __atomic_add_return(-i, v);
}
static inline int atomic_fetch_sub(int i, atomic_t *v)
{
if (IS_21BIT_CONST(i))
return __atomic_fetch_sub(i, v);
return __atomic_fetch_add(-i, v);
}
/*
* __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t

8
arch/blackfin/include/asm/atomic.h
View File

@ -17,6 +17,7 @@
asmlinkage int __raw_uncached_fetch_asm(const volatile int *ptr);
asmlinkage int __raw_atomic_add_asm(volatile int *ptr, int value);
asmlinkage int __raw_atomic_xadd_asm(volatile int *ptr, int value);
asmlinkage int __raw_atomic_and_asm(volatile int *ptr, int value);
asmlinkage int __raw_atomic_or_asm(volatile int *ptr, int value);
@ -28,10 +29,17 @@ asmlinkage int __raw_atomic_test_asm(const volatile int *ptr, int value);
#define atomic_add_return(i, v) __raw_atomic_add_asm(&(v)->counter, i)
#define atomic_sub_return(i, v) __raw_atomic_add_asm(&(v)->counter, -(i))
#define atomic_fetch_add(i, v) __raw_atomic_xadd_asm(&(v)->counter, i)
#define atomic_fetch_sub(i, v) __raw_atomic_xadd_asm(&(v)->counter, -(i))
#define atomic_or(i, v) (void)__raw_atomic_or_asm(&(v)->counter, i)
#define atomic_and(i, v) (void)__raw_atomic_and_asm(&(v)->counter, i)
#define atomic_xor(i, v) (void)__raw_atomic_xor_asm(&(v)->counter, i)
#define atomic_fetch_or(i, v) __raw_atomic_or_asm(&(v)->counter, i)
#define atomic_fetch_and(i, v) __raw_atomic_and_asm(&(v)->counter, i)
#define atomic_fetch_xor(i, v) __raw_atomic_xor_asm(&(v)->counter, i)
#endif
#include <asm-generic/atomic.h>

5
arch/blackfin/include/asm/spinlock.h
View File

@ -12,6 +12,8 @@
#else
#include <linux/atomic.h>
#include <asm/processor.h>
#include <asm/barrier.h>
asmlinkage int __raw_spin_is_locked_asm(volatile int *ptr);
asmlinkage void __raw_spin_lock_asm(volatile int *ptr);
@ -48,8 +50,7 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
while (arch_spin_is_locked(lock))
cpu_relax();
smp_cond_load_acquire(&lock->lock, !VAL);
}
static inline int arch_read_can_lock(arch_rwlock_t *rw)

1
arch/blackfin/kernel/bfin_ksyms.c
View File

@ -84,6 +84,7 @@ EXPORT_SYMBOL(insl_16);
#ifdef CONFIG_SMP
EXPORT_SYMBOL(__raw_atomic_add_asm);
EXPORT_SYMBOL(__raw_atomic_xadd_asm);
EXPORT_SYMBOL(__raw_atomic_and_asm);
EXPORT_SYMBOL(__raw_atomic_or_asm);
EXPORT_SYMBOL(__raw_atomic_xor_asm);

43
arch/blackfin/mach-bf561/atomic.S
View File

@ -605,6 +605,28 @@ ENTRY(___raw_atomic_add_asm)
rts;
ENDPROC(___raw_atomic_add_asm)
/*
* r0 = ptr
* r1 = value
*
* ADD a signed value to a 32bit word and return the old value atomically.
* Clobbers: r3:0, p1:0
*/
ENTRY(___raw_atomic_xadd_asm)
p1 = r0;
r3 = r1;
[--sp] = rets;
call _get_core_lock;
r3 = [p1];
r2 = r3 + r2;
[p1] = r2;
r1 = p1;
call _put_core_lock;
r0 = r3;
rets = [sp++];
rts;
ENDPROC(___raw_atomic_add_asm)
/*
* r0 = ptr
* r1 = mask
@ -618,10 +640,9 @@ ENTRY(___raw_atomic_and_asm)
r3 = r1;
[--sp] = rets;
call _get_core_lock;
r2 = [p1];
r3 = r2 & r3;
[p1] = r3;
r3 = r2;
r3 = [p1];
r2 = r2 & r3;
[p1] = r2;
r1 = p1;
call _put_core_lock;
r0 = r3;
@ -642,10 +663,9 @@ ENTRY(___raw_atomic_or_asm)
r3 = r1;
[--sp] = rets;
call _get_core_lock;
r2 = [p1];
r3 = r2 | r3;
[p1] = r3;
r3 = r2;
r3 = [p1];
r2 = r2 | r3;
[p1] = r2;
r1 = p1;
call _put_core_lock;
r0 = r3;
@ -666,10 +686,9 @@ ENTRY(___raw_atomic_xor_asm)
r3 = r1;
[--sp] = rets;
call _get_core_lock;
r2 = [p1];
r3 = r2 ^ r3;
[p1] = r3;
r3 = r2;
r3 = [p1];
r2 = r2 ^ r3;
[p1] = r2;
r1 = p1;
call _put_core_lock;
r0 = r3;

30
arch/frv/include/asm/atomic.h
View File

@ -60,16 +60,6 @@ static inline int atomic_add_negative(int i, atomic_t *v)
return atomic_add_return(i, v) < 0;
}
static inline void atomic_add(int i, atomic_t *v)
{
atomic_add_return(i, v);
}
static inline void atomic_sub(int i, atomic_t *v)
{
atomic_sub_return(i, v);
}
static inline void atomic_inc(atomic_t *v)
{
atomic_inc_return(v);
@ -136,16 +126,6 @@ static inline long long atomic64_add_negative(long long i, atomic64_t *v)
return atomic64_add_return(i, v) < 0;
}
static inline void atomic64_add(long long i, atomic64_t *v)
{
atomic64_add_return(i, v);
}
static inline void atomic64_sub(long long i, atomic64_t *v)
{
atomic64_sub_return(i, v);
}
static inline void atomic64_inc(atomic64_t *v)
{
atomic64_inc_return(v);
@ -182,11 +162,19 @@ static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
}
#define ATOMIC_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
return __atomic32_fetch_##op(i, &v->counter); \
} \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
(void)__atomic32_fetch_##op(i, &v->counter); \
} \
\
static inline long long atomic64_fetch_##op(long long i, atomic64_t *v) \
{ \
return __atomic64_fetch_##op(i, &v->counter); \
} \
static inline void atomic64_##op(long long i, atomic64_t *v) \
{ \
(void)__atomic64_fetch_##op(i, &v->counter); \
@ -195,6 +183,8 @@ static inline void atomic64_##op(long long i, atomic64_t *v) \
ATOMIC_OP(or)
ATOMIC_OP(and)
ATOMIC_OP(xor)
ATOMIC_OP(add)
ATOMIC_OP(sub)
#undef ATOMIC_OP

2
arch/frv/include/asm/atomic_defs.h
View File

@ -162,6 +162,8 @@ ATOMIC_EXPORT(__atomic64_fetch_##op);
ATOMIC_FETCH_OP(or)
ATOMIC_FETCH_OP(and)
ATOMIC_FETCH_OP(xor)
ATOMIC_FETCH_OP(add)
ATOMIC_FETCH_OP(sub)
ATOMIC_OP_RETURN(add)
ATOMIC_OP_RETURN(sub)

29
arch/h8300/include/asm/atomic.h
View File

@ -28,6 +28,19 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return ret; \
}
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
h8300flags flags; \
int ret; \
\
flags = arch_local_irq_save(); \
ret = v->counter; \
v->counter c_op i; \
arch_local_irq_restore(flags); \
return ret; \
}
#define ATOMIC_OP(op, c_op) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
@ -41,17 +54,21 @@ static inline void atomic_##op(int i, atomic_t *v) \
ATOMIC_OP_RETURN(add, +=)
ATOMIC_OP_RETURN(sub, -=)
ATOMIC_OP(and, &=)
ATOMIC_OP(or, |=)
ATOMIC_OP(xor, ^=)
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(and, &=)
ATOMIC_OPS(or, |=)
ATOMIC_OPS(xor, ^=)
ATOMIC_OPS(add, +=)
ATOMIC_OPS(sub, -=)
#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
#define atomic_add(i, v) (void)atomic_add_return(i, v)
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic_sub(i, v) (void)atomic_sub_return(i, v)
#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
#define atomic_inc_return(v) atomic_add_return(1, v)

31
arch/hexagon/include/asm/atomic.h
View File

@ -110,7 +110,7 @@ static inline void atomic_##op(int i, atomic_t *v) \
); \
} \
#define ATOMIC_OP_RETURN(op) \
#define ATOMIC_OP_RETURN(op) \
static inline int atomic_##op##_return(int i, atomic_t *v) \
{ \
int output; \
@ -127,16 +127,37 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return output; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int output, val; \
\
__asm__ __volatile__ ( \
"1: %0 = memw_locked(%2);\n" \
" %1 = "#op "(%0,%3);\n" \
" memw_locked(%2,P3)=%1;\n" \
" if !P3 jump 1b;\n" \
: "=&r" (output), "=&r" (val) \
: "r" (&v->counter), "r" (i) \
: "memory", "p3" \
); \
return output; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

10
arch/hexagon/include/asm/spinlock.h
View File

@ -23,6 +23,8 @@
#define _ASM_SPINLOCK_H
#include <asm/irqflags.h>
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* This file is pulled in for SMP builds.
@ -176,8 +178,12 @@ static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock)
* SMP spinlocks are intended to allow only a single CPU at the lock
*/
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_unlock_wait(lock) \
do {while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, !VAL);
}
#define arch_spin_is_locked(x) ((x)->lock != 0)
#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)

130
arch/ia64/include/asm/atomic.h
View File

@ -42,8 +42,27 @@ ia64_atomic_##op (int i, atomic_t *v) \
return new; \
}
ATOMIC_OP(add, +)
ATOMIC_OP(sub, -)
#define ATOMIC_FETCH_OP(op, c_op) \
static __inline__ int \
ia64_atomic_fetch_##op (int i, atomic_t *v) \
{ \
__s32 old, new; \
CMPXCHG_BUGCHECK_DECL \
\
do { \
CMPXCHG_BUGCHECK(v); \
old = atomic_read(v); \
new = old c_op i; \
} while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); \
return old; \
}
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(add, +)
ATOMIC_OPS(sub, -)
#define atomic_add_return(i,v) \
({ \
@ -69,14 +88,44 @@ ATOMIC_OP(sub, -)
: ia64_atomic_sub(__ia64_asr_i, v); \
})
ATOMIC_OP(and, &)
ATOMIC_OP(or, |)
ATOMIC_OP(xor, ^)
#define atomic_fetch_add(i,v) \
({ \
int __ia64_aar_i = (i); \
(__builtin_constant_p(i) \
&& ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \
|| (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \
|| (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \
|| (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \
? ia64_fetchadd(__ia64_aar_i, &(v)->counter, acq) \
: ia64_atomic_fetch_add(__ia64_aar_i, v); \
})
#define atomic_and(i,v) (void)ia64_atomic_and(i,v)
#define atomic_or(i,v) (void)ia64_atomic_or(i,v)
#define atomic_xor(i,v) (void)ia64_atomic_xor(i,v)
#define atomic_fetch_sub(i,v) \
({ \
int __ia64_asr_i = (i); \
(__builtin_constant_p(i) \
&& ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \
|| (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \
|| (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \
|| (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \
? ia64_fetchadd(-__ia64_asr_i, &(v)->counter, acq) \
: ia64_atomic_fetch_sub(__ia64_asr_i, v); \
})
ATOMIC_FETCH_OP(and, &)
ATOMIC_FETCH_OP(or, |)
ATOMIC_FETCH_OP(xor, ^)
#define atomic_and(i,v) (void)ia64_atomic_fetch_and(i,v)
#define atomic_or(i,v) (void)ia64_atomic_fetch_or(i,v)
#define atomic_xor(i,v) (void)ia64_atomic_fetch_xor(i,v)
#define atomic_fetch_and(i,v) ia64_atomic_fetch_and(i,v)
#define atomic_fetch_or(i,v) ia64_atomic_fetch_or(i,v)
#define atomic_fetch_xor(i,v) ia64_atomic_fetch_xor(i,v)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP
#define ATOMIC64_OP(op, c_op) \
@ -94,8 +143,27 @@ ia64_atomic64_##op (__s64 i, atomic64_t *v) \
return new; \
}
ATOMIC64_OP(add, +)
ATOMIC64_OP(sub, -)
#define ATOMIC64_FETCH_OP(op, c_op) \
static __inline__ long \
ia64_atomic64_fetch_##op (__s64 i, atomic64_t *v) \
{ \
__s64 old, new; \
CMPXCHG_BUGCHECK_DECL \
\
do { \
CMPXCHG_BUGCHECK(v); \
old = atomic64_read(v); \
new = old c_op i; \
} while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); \
return old; \
}
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op, c_op) \
ATOMIC64_FETCH_OP(op, c_op)
ATOMIC64_OPS(add, +)
ATOMIC64_OPS(sub, -)
#define atomic64_add_return(i,v) \
({ \
@ -121,14 +189,44 @@ ATOMIC64_OP(sub, -)
: ia64_atomic64_sub(__ia64_asr_i, v); \
})
ATOMIC64_OP(and, &)
ATOMIC64_OP(or, |)
ATOMIC64_OP(xor, ^)
#define atomic64_fetch_add(i,v) \
({ \
long __ia64_aar_i = (i); \
(__builtin_constant_p(i) \
&& ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \
|| (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \
|| (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \
|| (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \
? ia64_fetchadd(__ia64_aar_i, &(v)->counter, acq) \
: ia64_atomic64_fetch_add(__ia64_aar_i, v); \
})
#define atomic64_and(i,v) (void)ia64_atomic64_and(i,v)
#define atomic64_or(i,v) (void)ia64_atomic64_or(i,v)
#define atomic64_xor(i,v) (void)ia64_atomic64_xor(i,v)
#define atomic64_fetch_sub(i,v) \
({ \
long __ia64_asr_i = (i); \
(__builtin_constant_p(i) \
&& ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \
|| (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \
|| (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \
|| (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \
? ia64_fetchadd(-__ia64_asr_i, &(v)->counter, acq) \
: ia64_atomic64_fetch_sub(__ia64_asr_i, v); \
})
ATOMIC64_FETCH_OP(and, &)
ATOMIC64_FETCH_OP(or, |)
ATOMIC64_FETCH_OP(xor, ^)
#define atomic64_and(i,v) (void)ia64_atomic64_fetch_and(i,v)
#define atomic64_or(i,v) (void)ia64_atomic64_fetch_or(i,v)
#define atomic64_xor(i,v) (void)ia64_atomic64_fetch_xor(i,v)
#define atomic64_fetch_and(i,v) ia64_atomic64_fetch_and(i,v)
#define atomic64_fetch_or(i,v) ia64_atomic64_fetch_or(i,v)
#define atomic64_fetch_xor(i,v) ia64_atomic64_fetch_xor(i,v)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP
#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))

2
arch/ia64/include/asm/mutex.h
View File

@ -82,7 +82,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
static inline int
__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
{
if (cmpxchg_acq(count, 1, 0) == 1)
if (atomic_read(count) == 1 && cmpxchg_acq(count, 1, 0) == 1)
return 1;
return 0;
}

31
arch/ia64/include/asm/rwsem.h
View File

@ -40,7 +40,7 @@
static inline void
__down_read (struct rw_semaphore *sem)
{
long result = ia64_fetchadd8_acq((unsigned long *)&sem->count, 1);
long result = ia64_fetchadd8_acq((unsigned long *)&sem->count.counter, 1);
if (result < 0)
rwsem_down_read_failed(sem);
@ -55,9 +55,9 @@ ___down_write (struct rw_semaphore *sem)
long old, new;
do {
old = sem->count;
old = atomic_long_read(&sem->count);
new = old + RWSEM_ACTIVE_WRITE_BIAS;
} while (cmpxchg_acq(&sem->count, old, new) != old);
} while (atomic_long_cmpxchg_acquire(&sem->count, old, new) != old);
return old;
}
@ -85,7 +85,7 @@ __down_write_killable (struct rw_semaphore *sem)
static inline void
__up_read (struct rw_semaphore *sem)
{
long result = ia64_fetchadd8_rel((unsigned long *)&sem->count, -1);
long result = ia64_fetchadd8_rel((unsigned long *)&sem->count.counter, -1);
if (result < 0 && (--result & RWSEM_ACTIVE_MASK) == 0)
rwsem_wake(sem);
@ -100,9 +100,9 @@ __up_write (struct rw_semaphore *sem)
long old, new;
do {
old = sem->count;
old = atomic_long_read(&sem->count);
new = old - RWSEM_ACTIVE_WRITE_BIAS;
} while (cmpxchg_rel(&sem->count, old, new) != old);
} while (atomic_long_cmpxchg_release(&sem->count, old, new) != old);
if (new < 0 && (new & RWSEM_ACTIVE_MASK) == 0)
rwsem_wake(sem);
@ -115,8 +115,8 @@ static inline int
__down_read_trylock (struct rw_semaphore *sem)
{
long tmp;
while ((tmp = sem->count) >= 0) {
if (tmp == cmpxchg_acq(&sem->count, tmp, tmp+1)) {
while ((tmp = atomic_long_read(&sem->count)) >= 0) {
if (tmp == atomic_long_cmpxchg_acquire(&sem->count, tmp, tmp+1)) {
return 1;
}
}
@ -129,8 +129,8 @@ __down_read_trylock (struct rw_semaphore *sem)
static inline int
__down_write_trylock (struct rw_semaphore *sem)
{
long tmp = cmpxchg_acq(&sem->count, RWSEM_UNLOCKED_VALUE,
RWSEM_ACTIVE_WRITE_BIAS);
long tmp = atomic_long_cmpxchg_acquire(&sem->count,
RWSEM_UNLOCKED_VALUE, RWSEM_ACTIVE_WRITE_BIAS);
return tmp == RWSEM_UNLOCKED_VALUE;
}
@ -143,19 +143,12 @@ __downgrade_write (struct rw_semaphore *sem)
long old, new;
do {
old = sem->count;
old = atomic_long_read(&sem->count);
new = old - RWSEM_WAITING_BIAS;
} while (cmpxchg_rel(&sem->count, old, new) != old);
} while (atomic_long_cmpxchg_release(&sem->count, old, new) != old);
if (old < 0)
rwsem_downgrade_wake(sem);
}
/*
* Implement atomic add functionality. These used to be "inline" functions, but GCC v3.1
* doesn't quite optimize this stuff right and ends up with bad calls to fetchandadd.
*/
#define rwsem_atomic_add(delta, sem) atomic64_add(delta, (atomic64_t *)(&(sem)->count))
#define rwsem_atomic_update(delta, sem) atomic64_add_return(delta, (atomic64_t *)(&(sem)->count))
#endif /* _ASM_IA64_RWSEM_H */

4
arch/ia64/include/asm/spinlock.h
View File

@ -15,6 +15,8 @@
#include <linux/atomic.h>
#include <asm/intrinsics.h>
#include <asm/barrier.h>
#include <asm/processor.h>
#define arch_spin_lock_init(x) ((x)->lock = 0)
@ -86,6 +88,8 @@ static __always_inline void __ticket_spin_unlock_wait(arch_spinlock_t *lock)
return;
cpu_relax();
}
smp_acquire__after_ctrl_dep();
}
static inline int __ticket_spin_is_locked(arch_spinlock_t *lock)

36
arch/m32r/include/asm/atomic.h
View File

@ -89,16 +89,44 @@ static __inline__ int atomic_##op##_return(int i, atomic_t *v) \
return result; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static __inline__ int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
int result, val; \
\
local_irq_save(flags); \
__asm__ __volatile__ ( \
"# atomic_fetch_" #op " \n\t" \
DCACHE_CLEAR("%0", "r4", "%2") \
M32R_LOCK" %1, @%2; \n\t" \
"mv %0, %1 \n\t" \
#op " %1, %3; \n\t" \
M32R_UNLOCK" %1, @%2; \n\t" \
: "=&r" (result), "=&r" (val) \
: "r" (&v->counter), "r" (i) \
: "memory" \
__ATOMIC_CLOBBER \
); \
local_irq_restore(flags); \
\
return result; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

9
arch/m32r/include/asm/spinlock.h
View File

@ -13,6 +13,8 @@
#include <linux/atomic.h>
#include <asm/dcache_clear.h>
#include <asm/page.h>
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* Your basic SMP spinlocks, allowing only a single CPU anywhere
@ -27,8 +29,11 @@
#define arch_spin_is_locked(x) (*(volatile int *)(&(x)->slock) <= 0)
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_unlock_wait(x) \
do { cpu_relax(); } while (arch_spin_is_locked(x))
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->slock, VAL > 0);
}
/**
* arch_spin_trylock - Try spin lock and return a result

44
arch/m68k/include/asm/atomic.h
View File

@ -53,6 +53,21 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return t; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int t, tmp; \
\
__asm__ __volatile__( \
"1: movel %2,%1\n" \
" " #asm_op "l %3,%1\n" \
" casl %2,%1,%0\n" \
" jne 1b" \
: "+m" (*v), "=&d" (t), "=&d" (tmp) \
: "g" (i), "2" (atomic_read(v))); \
return tmp; \
}
#else
#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
@ -68,20 +83,41 @@ static inline int atomic_##op##_return(int i, atomic_t * v) \
return t; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static inline int atomic_fetch_##op(int i, atomic_t * v) \
{ \
unsigned long flags; \
int t; \
\
local_irq_save(flags); \
t = v->counter; \
v->counter c_op i; \
local_irq_restore(flags); \
\
return t; \
}
#endif /* CONFIG_RMW_INSNS */
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, add)
ATOMIC_OPS(sub, -=, sub)
ATOMIC_OP(and, &=, and)
ATOMIC_OP(or, |=, or)
ATOMIC_OP(xor, ^=, eor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, eor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

36
arch/metag/include/asm/atomic_lnkget.h
View File

@ -69,16 +69,44 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return result; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int result, temp; \
\
smp_mb(); \
\
asm volatile ( \
"1: LNKGETD %1, [%2]\n" \
" " #op " %0, %1, %3\n" \
" LNKSETD [%2], %0\n" \
" DEFR %0, TXSTAT\n" \
" ANDT %0, %0, #HI(0x3f000000)\n" \
" CMPT %0, #HI(0x02000000)\n" \
" BNZ 1b\n" \
: "=&d" (temp), "=&d" (result) \
: "da" (&v->counter), "bd" (i) \
: "cc"); \
\
smp_mb(); \
\
return result; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

33
arch/metag/include/asm/atomic_lock1.h
View File

@ -64,15 +64,40 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return result; \
}
#define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op)
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long result; \
unsigned long flags; \
\
__global_lock1(flags); \
result = v->counter; \
fence(); \
v->counter c_op i; \
__global_unlock1(flags); \
\
return result; \
}
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_OP_RETURN(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(add, +=)
ATOMIC_OPS(sub, -=)
ATOMIC_OP(and, &=)
ATOMIC_OP(or, |=)
ATOMIC_OP(xor, ^=)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(and, &=)
ATOMIC_OPS(or, |=)
ATOMIC_OPS(xor, ^=)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

14
arch/metag/include/asm/spinlock.h
View File

@ -1,14 +1,24 @@
#ifndef __ASM_SPINLOCK_H
#define __ASM_SPINLOCK_H
#include <asm/barrier.h>
#include <asm/processor.h>
#ifdef CONFIG_METAG_ATOMICITY_LOCK1
#include <asm/spinlock_lock1.h>
#else
#include <asm/spinlock_lnkget.h>
#endif
#define arch_spin_unlock_wait(lock) \
do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
/*
* both lock1 and lnkget are test-and-set spinlocks with 0 unlocked and 1
* locked.
*/
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, !VAL);
}
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)

154
arch/mips/include/asm/atomic.h
View File

@ -66,7 +66,7 @@ static __inline__ void atomic_##op(int i, atomic_t * v) \
" " #asm_op " %0, %2 \n" \
" sc %0, %1 \n" \
" .set mips0 \n" \
: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \
: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} while (unlikely(!temp)); \
} else { \
@ -79,12 +79,10 @@ static __inline__ void atomic_##op(int i, atomic_t * v) \
}
#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
static __inline__ int atomic_##op##_return(int i, atomic_t * v) \
static __inline__ int atomic_##op##_return_relaxed(int i, atomic_t * v) \
{ \
int result; \
\
smp_mb__before_llsc(); \
\
if (kernel_uses_llsc && R10000_LLSC_WAR) { \
int temp; \
\
@ -125,23 +123,84 @@ static __inline__ int atomic_##op##_return(int i, atomic_t * v) \
raw_local_irq_restore(flags); \
} \
\
smp_llsc_mb(); \
return result; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static __inline__ int atomic_fetch_##op##_relaxed(int i, atomic_t * v) \
{ \
int result; \
\
if (kernel_uses_llsc && R10000_LLSC_WAR) { \
int temp; \
\
__asm__ __volatile__( \
" .set arch=r4000 \n" \
"1: ll %1, %2 # atomic_fetch_" #op " \n" \
" " #asm_op " %0, %1, %3 \n" \
" sc %0, %2 \n" \
" beqzl %0, 1b \n" \
" move %0, %1 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else if (kernel_uses_llsc) { \
int temp; \
\
do { \
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
" ll %1, %2 # atomic_fetch_" #op " \n" \
" " #asm_op " %0, %1, %3 \n" \
" sc %0, %2 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} while (unlikely(!result)); \
\
result = temp; \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op)
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, addu)
ATOMIC_OPS(sub, -=, subu)
ATOMIC_OP(and, &=, and)
ATOMIC_OP(or, |=, or)
ATOMIC_OP(xor, ^=, xor)
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, xor)
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
@ -362,12 +421,10 @@ static __inline__ void atomic64_##op(long i, atomic64_t * v) \
}
#define ATOMIC64_OP_RETURN(op, c_op, asm_op) \
static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \
static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
{ \
long result; \
\
smp_mb__before_llsc(); \
\
if (kernel_uses_llsc && R10000_LLSC_WAR) { \
long temp; \
\
@ -409,22 +466,85 @@ static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \
raw_local_irq_restore(flags); \
} \
\
smp_llsc_mb(); \
return result; \
}
#define ATOMIC64_FETCH_OP(op, c_op, asm_op) \
static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v) \
{ \
long result; \
\
if (kernel_uses_llsc && R10000_LLSC_WAR) { \
long temp; \
\
__asm__ __volatile__( \
" .set arch=r4000 \n" \
"1: lld %1, %2 # atomic64_fetch_" #op "\n" \
" " #asm_op " %0, %1, %3 \n" \
" scd %0, %2 \n" \
" beqzl %0, 1b \n" \
" move %0, %1 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else if (kernel_uses_llsc) { \
long temp; \
\
do { \
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
" lld %1, %2 # atomic64_fetch_" #op "\n" \
" " #asm_op " %0, %1, %3 \n" \
" scd %0, %2 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"=" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter) \
: "memory"); \
} while (unlikely(!result)); \
\
result = temp; \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC64_OPS(op, c_op, asm_op) \
ATOMIC64_OP(op, c_op, asm_op) \
ATOMIC64_OP_RETURN(op, c_op, asm_op)
ATOMIC64_OP_RETURN(op, c_op, asm_op) \
ATOMIC64_FETCH_OP(op, c_op, asm_op)
ATOMIC64_OPS(add, +=, daddu)
ATOMIC64_OPS(sub, -=, dsubu)
ATOMIC64_OP(and, &=, and)
ATOMIC64_OP(or, |=, or)
ATOMIC64_OP(xor, ^=, xor)
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, c_op, asm_op) \
ATOMIC64_OP(op, c_op, asm_op) \
ATOMIC64_FETCH_OP(op, c_op, asm_op)
ATOMIC64_OPS(and, &=, and)
ATOMIC64_OPS(or, |=, or)
ATOMIC64_OPS(xor, ^=, xor)
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

19
arch/mips/include/asm/spinlock.h
View File

@ -12,6 +12,7 @@
#include <linux/compiler.h>
#include <asm/barrier.h>
#include <asm/processor.h>
#include <asm/compiler.h>
#include <asm/war.h>
@ -48,8 +49,22 @@ static inline int arch_spin_value_unlocked(arch_spinlock_t lock)
}
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_unlock_wait(x) \
while (arch_spin_is_locked(x)) { cpu_relax(); }
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
u16 owner = READ_ONCE(lock->h.serving_now);
smp_rmb();
for (;;) {
arch_spinlock_t tmp = READ_ONCE(*lock);
if (tmp.h.serving_now == tmp.h.ticket ||
tmp.h.serving_now != owner)
break;
cpu_relax();
}
smp_acquire__after_ctrl_dep();
}
static inline int arch_spin_is_contended(arch_spinlock_t *lock)
{

33
arch/mn10300/include/asm/atomic.h
View File

@ -84,16 +84,41 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return retval; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int retval, status; \
\
asm volatile( \
"1: mov %4,(_AAR,%3) \n" \
" mov (_ADR,%3),%1 \n" \
" mov %1,%0 \n" \
" " #op " %5,%0 \n" \
" mov %0,(_ADR,%3) \n" \
" mov (_ADR,%3),%0 \n" /* flush */ \
" mov (_ASR,%3),%0 \n" \
" or %0,%0 \n" \
" bne 1b \n" \
: "=&r"(status), "=&r"(retval), "=m"(v->counter) \
: "a"(ATOMIC_OPS_BASE_ADDR), "r"(&v->counter), "r"(i) \
: "memory", "cc"); \
return retval; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

8
arch/mn10300/include/asm/spinlock.h
View File

@ -12,6 +12,8 @@
#define _ASM_SPINLOCK_H
#include <linux/atomic.h>
#include <asm/barrier.h>
#include <asm/processor.h>
#include <asm/rwlock.h>
#include <asm/page.h>
@ -23,7 +25,11 @@
*/
#define arch_spin_is_locked(x) (*(volatile signed char *)(&(x)->slock) != 0)
#define arch_spin_unlock_wait(x) do { barrier(); } while (arch_spin_is_locked(x))
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->slock, !VAL);
}
static inline void arch_spin_unlock(arch_spinlock_t *lock)
{

63
arch/parisc/include/asm/atomic.h
View File

@ -121,16 +121,39 @@ static __inline__ int atomic_##op##_return(int i, atomic_t *v) \
return ret; \
}
#define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op)
#define ATOMIC_FETCH_OP(op, c_op) \
static __inline__ int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
int ret; \
\
_atomic_spin_lock_irqsave(v, flags); \
ret = v->counter; \
v->counter c_op i; \
_atomic_spin_unlock_irqrestore(v, flags); \
\
return ret; \
}
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_OP_RETURN(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(add, +=)
ATOMIC_OPS(sub, -=)
ATOMIC_OP(and, &=)
ATOMIC_OP(or, |=)
ATOMIC_OP(xor, ^=)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(and, &=)
ATOMIC_OPS(or, |=)
ATOMIC_OPS(xor, ^=)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
@ -185,15 +208,39 @@ static __inline__ s64 atomic64_##op##_return(s64 i, atomic64_t *v) \
return ret; \
}
#define ATOMIC64_OPS(op, c_op) ATOMIC64_OP(op, c_op) ATOMIC64_OP_RETURN(op, c_op)
#define ATOMIC64_FETCH_OP(op, c_op) \
static __inline__ s64 atomic64_fetch_##op(s64 i, atomic64_t *v) \
{ \
unsigned long flags; \
s64 ret; \
\
_atomic_spin_lock_irqsave(v, flags); \
ret = v->counter; \
v->counter c_op i; \
_atomic_spin_unlock_irqrestore(v, flags); \
\
return ret; \
}
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op, c_op) \
ATOMIC64_OP_RETURN(op, c_op) \
ATOMIC64_FETCH_OP(op, c_op)
ATOMIC64_OPS(add, +=)
ATOMIC64_OPS(sub, -=)
ATOMIC64_OP(and, &=)
ATOMIC64_OP(or, |=)
ATOMIC64_OP(xor, ^=)
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op, c_op) \
ATOMIC64_FETCH_OP(op, c_op)
ATOMIC64_OPS(and, &=)
ATOMIC64_OPS(or, |=)
ATOMIC64_OPS(xor, ^=)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

9
arch/parisc/include/asm/spinlock.h
View File

@ -13,8 +13,13 @@ static inline int arch_spin_is_locked(arch_spinlock_t *x)
}
#define arch_spin_lock(lock) arch_spin_lock_flags(lock, 0)
#define arch_spin_unlock_wait(x) \
do { cpu_relax(); } while (arch_spin_is_locked(x))
static inline void arch_spin_unlock_wait(arch_spinlock_t *x)
{
volatile unsigned int *a = __ldcw_align(x);
smp_cond_load_acquire(a, VAL);
}
static inline void arch_spin_lock_flags(arch_spinlock_t *x,
unsigned long flags)

83
arch/powerpc/include/asm/atomic.h
View File

@ -78,21 +78,53 @@ static inline int atomic_##op##_return_relaxed(int a, atomic_t *v) \
return t; \
}
#define ATOMIC_FETCH_OP_RELAXED(op, asm_op) \
static inline int atomic_fetch_##op##_relaxed(int a, atomic_t *v) \
{ \
int res, t; \
\
__asm__ __volatile__( \
"1: lwarx %0,0,%4 # atomic_fetch_" #op "_relaxed\n" \
#asm_op " %1,%3,%0\n" \
PPC405_ERR77(0, %4) \
" stwcx. %1,0,%4\n" \
" bne- 1b\n" \
: "=&r" (res), "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return res; \
}
#define ATOMIC_OPS(op, asm_op) \
ATOMIC_OP(op, asm_op) \
ATOMIC_OP_RETURN_RELAXED(op, asm_op)
ATOMIC_OP_RETURN_RELAXED(op, asm_op) \
ATOMIC_FETCH_OP_RELAXED(op, asm_op)
ATOMIC_OPS(add, add)
ATOMIC_OPS(sub, subf)
ATOMIC_OP(and, and)
ATOMIC_OP(or, or)
ATOMIC_OP(xor, xor)
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, asm_op) \
ATOMIC_OP(op, asm_op) \
ATOMIC_FETCH_OP_RELAXED(op, asm_op)
ATOMIC_OPS(and, and)
ATOMIC_OPS(or, or)
ATOMIC_OPS(xor, xor)
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP_RELAXED
#undef ATOMIC_OP_RETURN_RELAXED
#undef ATOMIC_OP
@ -329,20 +361,53 @@ atomic64_##op##_return_relaxed(long a, atomic64_t *v) \
return t; \
}
#define ATOMIC64_FETCH_OP_RELAXED(op, asm_op) \
static inline long \
atomic64_fetch_##op##_relaxed(long a, atomic64_t *v) \
{ \
long res, t; \
\
__asm__ __volatile__( \
"1: ldarx %0,0,%4 # atomic64_fetch_" #op "_relaxed\n" \
#asm_op " %1,%3,%0\n" \
" stdcx. %1,0,%4\n" \
" bne- 1b\n" \
: "=&r" (res), "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return res; \
}
#define ATOMIC64_OPS(op, asm_op) \
ATOMIC64_OP(op, asm_op) \
ATOMIC64_OP_RETURN_RELAXED(op, asm_op)
ATOMIC64_OP_RETURN_RELAXED(op, asm_op) \
ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
ATOMIC64_OPS(add, add)
ATOMIC64_OPS(sub, subf)
ATOMIC64_OP(and, and)
ATOMIC64_OP(or, or)
ATOMIC64_OP(xor, xor)
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, asm_op) \
ATOMIC64_OP(op, asm_op) \
ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
ATOMIC64_OPS(and, and)
ATOMIC64_OPS(or, or)
ATOMIC64_OPS(xor, xor)
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#undef ATOPIC64_OPS
#undef ATOMIC64_FETCH_OP_RELAXED
#undef ATOMIC64_OP_RETURN_RELAXED
#undef ATOMIC64_OP

2
arch/powerpc/include/asm/mutex.h
View File

@ -124,7 +124,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
static inline int
__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
{
if (likely(__mutex_cmpxchg_lock(count, 1, 0) == 1))
if (likely(atomic_read(count) == 1 && __mutex_cmpxchg_lock(count, 1, 0) == 1))
return 1;
return 0;
}

40
arch/s390/include/asm/atomic.h
View File

@ -93,6 +93,11 @@ static inline int atomic_add_return(int i, atomic_t *v)
return __ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_BARRIER) + i;
}
static inline int atomic_fetch_add(int i, atomic_t *v)
{
return __ATOMIC_LOOP(v, i, __ATOMIC_ADD, __ATOMIC_BARRIER);
}
static inline void atomic_add(int i, atomic_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
@ -114,22 +119,27 @@ static inline void atomic_add(int i, atomic_t *v)
#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0)
#define atomic_sub(_i, _v) atomic_add(-(int)(_i), _v)
#define atomic_sub_return(_i, _v) atomic_add_return(-(int)(_i), _v)
#define atomic_fetch_sub(_i, _v) atomic_fetch_add(-(int)(_i), _v)
#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0)
#define atomic_dec(_v) atomic_sub(1, _v)
#define atomic_dec_return(_v) atomic_sub_return(1, _v)
#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
#define ATOMIC_OP(op, OP) \
#define ATOMIC_OPS(op, OP) \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
__ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_NO_BARRIER); \
} \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
return __ATOMIC_LOOP(v, i, __ATOMIC_##OP, __ATOMIC_BARRIER); \
}
ATOMIC_OP(and, AND)
ATOMIC_OP(or, OR)
ATOMIC_OP(xor, XOR)
ATOMIC_OPS(and, AND)
ATOMIC_OPS(or, OR)
ATOMIC_OPS(xor, XOR)
#undef ATOMIC_OP
#undef ATOMIC_OPS
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
@ -236,6 +246,11 @@ static inline long long atomic64_add_return(long long i, atomic64_t *v)
return __ATOMIC64_LOOP(v, i, __ATOMIC64_ADD, __ATOMIC64_BARRIER) + i;
}
static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
{
return __ATOMIC64_LOOP(v, i, __ATOMIC64_ADD, __ATOMIC64_BARRIER);
}
static inline void atomic64_add(long long i, atomic64_t *v)
{
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
@ -264,17 +279,21 @@ static inline long long atomic64_cmpxchg(atomic64_t *v,
return old;
}
#define ATOMIC64_OP(op, OP) \
#define ATOMIC64_OPS(op, OP) \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
__ATOMIC64_LOOP(v, i, __ATOMIC64_##OP, __ATOMIC64_NO_BARRIER); \
} \
static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
{ \
return __ATOMIC64_LOOP(v, i, __ATOMIC64_##OP, __ATOMIC64_BARRIER); \
}
ATOMIC64_OP(and, AND)
ATOMIC64_OP(or, OR)
ATOMIC64_OP(xor, XOR)
ATOMIC64_OPS(and, AND)
ATOMIC64_OPS(or, OR)
ATOMIC64_OPS(xor, XOR)
#undef ATOMIC64_OP
#undef ATOMIC64_OPS
#undef __ATOMIC64_LOOP
static inline int atomic64_add_unless(atomic64_t *v, long long i, long long u)
@ -315,6 +334,7 @@ static inline long long atomic64_dec_if_positive(atomic64_t *v)
#define atomic64_inc_return(_v) atomic64_add_return(1, _v)
#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0)
#define atomic64_sub_return(_i, _v) atomic64_add_return(-(long long)(_i), _v)
#define atomic64_fetch_sub(_i, _v) atomic64_fetch_add(-(long long)(_i), _v)
#define atomic64_sub(_i, _v) atomic64_add(-(long long)(_i), _v)
#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0)
#define atomic64_dec(_v) atomic64_sub(1, _v)

37
arch/s390/include/asm/rwsem.h
View File

@ -207,41 +207,4 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
rwsem_downgrade_wake(sem);
}
/*
* implement atomic add functionality
*/
static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
{
signed long old, new;
asm volatile(
" lg %0,%2\n"
"0: lgr %1,%0\n"
" agr %1,%4\n"
" csg %0,%1,%2\n"
" jl 0b"
: "=&d" (old), "=&d" (new), "=Q" (sem->count)
: "Q" (sem->count), "d" (delta)
: "cc", "memory");
}
/*
* implement exchange and add functionality
*/
static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
{
signed long old, new;
asm volatile(
" lg %0,%2\n"
"0: lgr %1,%0\n"
" agr %1,%4\n"
" csg %0,%1,%2\n"
" jl 0b"
: "=&d" (old), "=&d" (new), "=Q" (sem->count)
: "Q" (sem->count), "d" (delta)
: "cc", "memory");
return new;
}
#endif /* _S390_RWSEM_H */

3
arch/s390/include/asm/spinlock.h
View File

@ -10,6 +10,8 @@
#define __ASM_SPINLOCK_H
#include <linux/smp.h>
#include <asm/barrier.h>
#include <asm/processor.h>
#define SPINLOCK_LOCKVAL (S390_lowcore.spinlock_lockval)
@ -97,6 +99,7 @@ static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
while (arch_spin_is_locked(lock))
arch_spin_relax(lock);
smp_acquire__after_ctrl_dep();
}
/*

34
arch/sh/include/asm/atomic-grb.h
View File

@ -43,16 +43,42 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return tmp; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int res, tmp; \
\
__asm__ __volatile__ ( \
" .align 2 \n\t" \
" mova 1f, r0 \n\t" /* r0 = end point */ \
" mov r15, r1 \n\t" /* r1 = saved sp */ \
" mov #-6, r15 \n\t" /* LOGIN: r15 = size */ \
" mov.l @%2, %0 \n\t" /* load old value */ \
" mov %0, %1 \n\t" /* save old value */ \
" " #op " %3, %0 \n\t" /* $op */ \
" mov.l %0, @%2 \n\t" /* store new value */ \
"1: mov r1, r15 \n\t" /* LOGOUT */ \
: "=&r" (tmp), "=&r" (res), "+r" (v) \
: "r" (i) \
: "memory" , "r0", "r1"); \
\
return res; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

31
arch/sh/include/asm/atomic-irq.h
View File

@ -33,15 +33,38 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
#define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op)
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long temp, flags; \
\
raw_local_irq_save(flags); \
temp = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
\
return temp; \
}
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_OP_RETURN(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(add, +=)
ATOMIC_OPS(sub, -=)
ATOMIC_OP(and, &=)
ATOMIC_OP(or, |=)
ATOMIC_OP(xor, ^=)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op, c_op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(and, &=)
ATOMIC_OPS(or, |=)
ATOMIC_OPS(xor, ^=)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

32
arch/sh/include/asm/atomic-llsc.h
View File

@ -48,15 +48,39 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return temp; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long res, temp; \
\
__asm__ __volatile__ ( \
"1: movli.l @%3, %0 ! atomic_fetch_" #op " \n" \
" mov %0, %1 \n" \
" " #op " %2, %0 \n" \
" movco.l %0, @%3 \n" \
" bf 1b \n" \
" synco \n" \
: "=&z" (temp), "=&z" (res) \
: "r" (i), "r" (&v->counter) \
: "t"); \
\
return res; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

10
arch/sh/include/asm/spinlock.h
View File

@ -19,14 +19,20 @@
#error "Need movli.l/movco.l for spinlocks"
#endif
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* Your basic SMP spinlocks, allowing only a single CPU anywhere
*/
#define arch_spin_is_locked(x) ((x)->lock <= 0)
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
#define arch_spin_unlock_wait(x) \
do { while (arch_spin_is_locked(x)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, VAL > 0);
}
/*
* Simple spin lock operations. There are two variants, one clears IRQ's

13
arch/sparc/include/asm/atomic_32.h
View File

@ -20,9 +20,10 @@
#define ATOMIC_INIT(i) { (i) }
int atomic_add_return(int, atomic_t *);
void atomic_and(int, atomic_t *);
void atomic_or(int, atomic_t *);
void atomic_xor(int, atomic_t *);
int atomic_fetch_add(int, atomic_t *);
int atomic_fetch_and(int, atomic_t *);
int atomic_fetch_or(int, atomic_t *);
int atomic_fetch_xor(int, atomic_t *);
int atomic_cmpxchg(atomic_t *, int, int);
int atomic_xchg(atomic_t *, int);
int __atomic_add_unless(atomic_t *, int, int);
@ -35,7 +36,13 @@ void atomic_set(atomic_t *, int);
#define atomic_inc(v) ((void)atomic_add_return( 1, (v)))
#define atomic_dec(v) ((void)atomic_add_return( -1, (v)))
#define atomic_and(i, v) ((void)atomic_fetch_and((i), (v)))
#define atomic_or(i, v) ((void)atomic_fetch_or((i), (v)))
#define atomic_xor(i, v) ((void)atomic_fetch_xor((i), (v)))
#define atomic_sub_return(i, v) (atomic_add_return(-(int)(i), (v)))
#define atomic_fetch_sub(i, v) (atomic_fetch_add (-(int)(i), (v)))
#define atomic_inc_return(v) (atomic_add_return( 1, (v)))
#define atomic_dec_return(v) (atomic_add_return( -1, (v)))

16
arch/sparc/include/asm/atomic_64.h
View File

@ -28,16 +28,24 @@ void atomic64_##op(long, atomic64_t *);
int atomic_##op##_return(int, atomic_t *); \
long atomic64_##op##_return(long, atomic64_t *);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
int atomic_fetch_##op(int, atomic_t *); \
long atomic64_fetch_##op(long, atomic64_t *);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

7
arch/sparc/include/asm/spinlock_32.h
View File

@ -9,12 +9,15 @@
#ifndef __ASSEMBLY__
#include <asm/psr.h>
#include <asm/barrier.h>
#include <asm/processor.h> /* for cpu_relax */
#define arch_spin_is_locked(lock) (*((volatile unsigned char *)(lock)) != 0)
#define arch_spin_unlock_wait(lock) \
do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, !VAL);
}
static inline void arch_spin_lock(arch_spinlock_t *lock)
{

10
arch/sparc/include/asm/spinlock_64.h
View File

@ -8,6 +8,9 @@
#ifndef __ASSEMBLY__
#include <asm/processor.h>
#include <asm/barrier.h>
/* To get debugging spinlocks which detect and catch
* deadlock situations, set CONFIG_DEBUG_SPINLOCK
* and rebuild your kernel.
@ -23,9 +26,10 @@
#define arch_spin_is_locked(lp) ((lp)->lock != 0)
#define arch_spin_unlock_wait(lp) \
do { rmb(); \
} while((lp)->lock)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->lock, !VAL);
}
static inline void arch_spin_lock(arch_spinlock_t *lock)
{

37
arch/sparc/lib/atomic32.c
View File

@ -27,6 +27,21 @@ static DEFINE_SPINLOCK(dummy);
#endif /* SMP */
#define ATOMIC_FETCH_OP(op, c_op) \
int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int ret; \
unsigned long flags; \
spin_lock_irqsave(ATOMIC_HASH(v), flags); \
\
ret = v->counter; \
v->counter c_op i; \
\
spin_unlock_irqrestore(ATOMIC_HASH(v), flags); \
return ret; \
} \
EXPORT_SYMBOL(atomic_fetch_##op);
#define ATOMIC_OP_RETURN(op, c_op) \
int atomic_##op##_return(int i, atomic_t *v) \
{ \
@ -41,25 +56,15 @@ int atomic_##op##_return(int i, atomic_t *v) \
} \
EXPORT_SYMBOL(atomic_##op##_return);
#define ATOMIC_OP(op, c_op) \
void atomic_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
spin_lock_irqsave(ATOMIC_HASH(v), flags); \
\
v->counter c_op i; \
\
spin_unlock_irqrestore(ATOMIC_HASH(v), flags); \
} \
EXPORT_SYMBOL(atomic_##op);
ATOMIC_OP_RETURN(add, +=)
ATOMIC_OP(and, &=)
ATOMIC_OP(or, |=)
ATOMIC_OP(xor, ^=)
ATOMIC_FETCH_OP(add, +=)
ATOMIC_FETCH_OP(and, &=)
ATOMIC_FETCH_OP(or, |=)
ATOMIC_FETCH_OP(xor, ^=)
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
int atomic_xchg(atomic_t *v, int new)
{

61
arch/sparc/lib/atomic_64.S
View File

@ -9,10 +9,11 @@
.text
/* Two versions of the atomic routines, one that
/* Three versions of the atomic routines, one that
* does not return a value and does not perform
* memory barriers, and a second which returns
* a value and does the barriers.
* memory barriers, and a two which return
* a value, the new and old value resp. and does the
* barriers.
*/
#define ATOMIC_OP(op) \
@ -43,15 +44,34 @@ ENTRY(atomic_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic_##op##_return);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
ENTRY(atomic_fetch_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: lduw [%o1], %g1; \
op %g1, %o0, %g7; \
cas [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
sra %g1, 0, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic_fetch_##op);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
@ -83,15 +103,34 @@ ENTRY(atomic64_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic64_##op##_return);
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op)
#define ATOMIC64_FETCH_OP(op) \
ENTRY(atomic64_fetch_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: ldx [%o1], %g1; \
op %g1, %o0, %g7; \
casx [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
mov %g1, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic64_fetch_##op);
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) ATOMIC64_FETCH_OP(op)
ATOMIC64_OPS(add)
ATOMIC64_OPS(sub)
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_FETCH_OP(op)
ATOMIC64_OPS(and)
ATOMIC64_OPS(or)
ATOMIC64_OPS(xor)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

17
arch/sparc/lib/ksyms.c
View File

@ -107,15 +107,24 @@ EXPORT_SYMBOL(atomic64_##op);
EXPORT_SYMBOL(atomic_##op##_return); \
EXPORT_SYMBOL(atomic64_##op##_return);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_FETCH_OP(op) \
EXPORT_SYMBOL(atomic_fetch_##op); \
EXPORT_SYMBOL(atomic64_fetch_##op);
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

2
arch/tile/include/asm/atomic.h
View File

@ -46,6 +46,8 @@ static inline int atomic_read(const atomic_t *v)
*/
#define atomic_sub_return(i, v) atomic_add_return((int)(-(i)), (v))
#define atomic_fetch_sub(i, v) atomic_fetch_add(-(int)(i), (v))
/**
* atomic_sub - subtract integer from atomic variable
* @i: integer value to subtract

74
arch/tile/include/asm/atomic_32.h
View File

@ -34,18 +34,29 @@ static inline void atomic_add(int i, atomic_t *v)
_atomic_xchg_add(&v->counter, i);
}
#define ATOMIC_OP(op) \
unsigned long _atomic_##op(volatile unsigned long *p, unsigned long mask); \
#define ATOMIC_OPS(op) \
unsigned long _atomic_fetch_##op(volatile unsigned long *p, unsigned long mask); \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
_atomic_##op((unsigned long *)&v->counter, i); \
_atomic_fetch_##op((unsigned long *)&v->counter, i); \
} \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
smp_mb(); \
return _atomic_fetch_##op((unsigned long *)&v->counter, i); \
}
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OP
#undef ATOMIC_OPS
static inline int atomic_fetch_add(int i, atomic_t *v)
{
smp_mb();
return _atomic_xchg_add(&v->counter, i);
}
/**
* atomic_add_return - add integer and return
@ -126,16 +137,29 @@ static inline void atomic64_add(long long i, atomic64_t *v)
_atomic64_xchg_add(&v->counter, i);
}
#define ATOMIC64_OP(op) \
long long _atomic64_##op(long long *v, long long n); \
#define ATOMIC64_OPS(op) \
long long _atomic64_fetch_##op(long long *v, long long n); \
static inline void atomic64_##op(long long i, atomic64_t *v) \
{ \
_atomic64_##op(&v->counter, i); \
_atomic64_fetch_##op(&v->counter, i); \
} \
static inline long long atomic64_fetch_##op(long long i, atomic64_t *v) \
{ \
smp_mb(); \
return _atomic64_fetch_##op(&v->counter, i); \
}
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)
ATOMIC64_OPS(and)
ATOMIC64_OPS(or)
ATOMIC64_OPS(xor)
#undef ATOMIC64_OPS
static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
{
smp_mb();
return _atomic64_xchg_add(&v->counter, i);
}
/**
* atomic64_add_return - add integer and return
@ -186,6 +210,7 @@ static inline void atomic64_set(atomic64_t *v, long long n)
#define atomic64_inc_return(v) atomic64_add_return(1LL, (v))
#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
#define atomic64_sub_return(i, v) atomic64_add_return(-(i), (v))
#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
#define atomic64_sub(i, v) atomic64_add(-(i), (v))
#define atomic64_dec(v) atomic64_sub(1LL, (v))
@ -193,7 +218,6 @@ static inline void atomic64_set(atomic64_t *v, long long n)
#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL)
#endif /* !__ASSEMBLY__ */
/*
@ -242,16 +266,16 @@ struct __get_user {
unsigned long val;
int err;
};
extern struct __get_user __atomic_cmpxchg(volatile int *p,
extern struct __get_user __atomic32_cmpxchg(volatile int *p,
int *lock, int o, int n);
extern struct __get_user __atomic_xchg(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add_unless(volatile int *p,
extern struct __get_user __atomic32_xchg(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_xchg_add(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_xchg_add_unless(volatile int *p,
int *lock, int o, int n);
extern struct __get_user __atomic_or(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_and(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_andn(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xor(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_fetch_or(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_fetch_and(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_fetch_andn(volatile int *p, int *lock, int n);
extern struct __get_user __atomic32_fetch_xor(volatile int *p, int *lock, int n);
extern long long __atomic64_cmpxchg(volatile long long *p, int *lock,
long long o, long long n);
extern long long __atomic64_xchg(volatile long long *p, int *lock, long long n);
@ -259,9 +283,9 @@ extern long long __atomic64_xchg_add(volatile long long *p, int *lock,
long long n);
extern long long __atomic64_xchg_add_unless(volatile long long *p,
int *lock, long long o, long long n);
extern long long __atomic64_and(volatile long long *p, int *lock, long long n);
extern long long __atomic64_or(volatile long long *p, int *lock, long long n);
extern long long __atomic64_xor(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_and(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_or(volatile long long *p, int *lock, long long n);
extern long long __atomic64_fetch_xor(volatile long long *p, int *lock, long long n);
/* Return failure from the atomic wrappers. */
struct __get_user __atomic_bad_address(int __user *addr);

125
arch/tile/include/asm/atomic_64.h
View File

@ -32,11 +32,6 @@
* on any routine which updates memory and returns a value.
*/
static inline void atomic_add(int i, atomic_t *v)
{
__insn_fetchadd4((void *)&v->counter, i);
}
/*
* Note a subtlety of the locking here. We are required to provide a
* full memory barrier before and after the operation. However, we
@ -59,28 +54,39 @@ static inline int atomic_add_return(int i, atomic_t *v)
return val;
}
static inline int __atomic_add_unless(atomic_t *v, int a, int u)
#define ATOMIC_OPS(op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int val; \
smp_mb(); \
val = __insn_fetch##op##4((void *)&v->counter, i); \
smp_mb(); \
return val; \
} \
static inline void atomic_##op(int i, atomic_t *v) \
{ \
__insn_fetch##op##4((void *)&v->counter, i); \
}
ATOMIC_OPS(add)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
#undef ATOMIC_OPS
static inline int atomic_fetch_xor(int i, atomic_t *v)
{
int guess, oldval = v->counter;
smp_mb();
do {
if (oldval == u)
break;
guess = oldval;
oldval = cmpxchg(&v->counter, guess, guess + a);
__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
oldval = __insn_cmpexch4(&v->counter, guess ^ i);
} while (guess != oldval);
smp_mb();
return oldval;
}
static inline void atomic_and(int i, atomic_t *v)
{
__insn_fetchand4((void *)&v->counter, i);
}
static inline void atomic_or(int i, atomic_t *v)
{
__insn_fetchor4((void *)&v->counter, i);
}
static inline void atomic_xor(int i, atomic_t *v)
{
int guess, oldval = v->counter;
@ -91,6 +97,18 @@ static inline void atomic_xor(int i, atomic_t *v)
} while (guess != oldval);
}
static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int guess, oldval = v->counter;
do {
if (oldval == u)
break;
guess = oldval;
oldval = cmpxchg(&v->counter, guess, guess + a);
} while (guess != oldval);
return oldval;
}
/* Now the true 64-bit operations. */
#define ATOMIC64_INIT(i) { (i) }
@ -98,11 +116,6 @@ static inline void atomic_xor(int i, atomic_t *v)
#define atomic64_read(v) READ_ONCE((v)->counter)
#define atomic64_set(v, i) WRITE_ONCE((v)->counter, (i))
static inline void atomic64_add(long i, atomic64_t *v)
{
__insn_fetchadd((void *)&v->counter, i);
}
static inline long atomic64_add_return(long i, atomic64_t *v)
{
int val;
@ -112,6 +125,49 @@ static inline long atomic64_add_return(long i, atomic64_t *v)
return val;
}
#define ATOMIC64_OPS(op) \
static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
{ \
long val; \
smp_mb(); \
val = __insn_fetch##op((void *)&v->counter, i); \
smp_mb(); \
return val; \
} \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
__insn_fetch##op((void *)&v->counter, i); \
}
ATOMIC64_OPS(add)
ATOMIC64_OPS(and)
ATOMIC64_OPS(or)
#undef ATOMIC64_OPS
static inline long atomic64_fetch_xor(long i, atomic64_t *v)
{
long guess, oldval = v->counter;
smp_mb();
do {
guess = oldval;
__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
oldval = __insn_cmpexch(&v->counter, guess ^ i);
} while (guess != oldval);
smp_mb();
return oldval;
}
static inline void atomic64_xor(long i, atomic64_t *v)
{
long guess, oldval = v->counter;
do {
guess = oldval;
__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
oldval = __insn_cmpexch(&v->counter, guess ^ i);
} while (guess != oldval);
}
static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
{
long guess, oldval = v->counter;
@ -124,27 +180,8 @@ static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
return oldval != u;
}
static inline void atomic64_and(long i, atomic64_t *v)
{
__insn_fetchand((void *)&v->counter, i);
}
static inline void atomic64_or(long i, atomic64_t *v)
{
__insn_fetchor((void *)&v->counter, i);
}
static inline void atomic64_xor(long i, atomic64_t *v)
{
long guess, oldval = v->counter;
do {
guess = oldval;
__insn_mtspr(SPR_CMPEXCH_VALUE, guess);
oldval = __insn_cmpexch(&v->counter, guess ^ i);
} while (guess != oldval);
}
#define atomic64_sub_return(i, v) atomic64_add_return(-(i), (v))
#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
#define atomic64_sub(i, v) atomic64_add(-(i), (v))
#define atomic64_inc_return(v) atomic64_add_return(1, (v))
#define atomic64_dec_return(v) atomic64_sub_return(1, (v))

7
arch/tile/include/asm/barrier.h
View File

@ -87,6 +87,13 @@ mb_incoherent(void)
#define __smp_mb__after_atomic() __smp_mb()
#endif
/*
* The TILE architecture does not do speculative reads; this ensures
* that a control dependency also orders against loads and already provides
* a LOAD->{LOAD,STORE} order and can forgo the additional RMB.
*/
#define smp_acquire__after_ctrl_dep() barrier()
#include <asm-generic/barrier.h>
#endif /* !__ASSEMBLY__ */

18
arch/tile/include/asm/bitops_32.h
View File

@ -19,9 +19,9 @@
#include <asm/barrier.h>
/* Tile-specific routines to support <asm/bitops.h>. */
unsigned long _atomic_or(volatile unsigned long *p, unsigned long mask);
unsigned long _atomic_andn(volatile unsigned long *p, unsigned long mask);
unsigned long _atomic_xor(volatile unsigned long *p, unsigned long mask);
unsigned long _atomic_fetch_or(volatile unsigned long *p, unsigned long mask);
unsigned long _atomic_fetch_andn(volatile unsigned long *p, unsigned long mask);
unsigned long _atomic_fetch_xor(volatile unsigned long *p, unsigned long mask);
/**
* set_bit - Atomically set a bit in memory
@ -35,7 +35,7 @@ unsigned long _atomic_xor(volatile unsigned long *p, unsigned long mask);
*/
static inline void set_bit(unsigned nr, volatile unsigned long *addr)
{
_atomic_or(addr + BIT_WORD(nr), BIT_MASK(nr));
_atomic_fetch_or(addr + BIT_WORD(nr), BIT_MASK(nr));
}
/**
@ -54,7 +54,7 @@ static inline void set_bit(unsigned nr, volatile unsigned long *addr)
*/
static inline void clear_bit(unsigned nr, volatile unsigned long *addr)
{
_atomic_andn(addr + BIT_WORD(nr), BIT_MASK(nr));
_atomic_fetch_andn(addr + BIT_WORD(nr), BIT_MASK(nr));
}
/**
@ -69,7 +69,7 @@ static inline void clear_bit(unsigned nr, volatile unsigned long *addr)
*/
static inline void change_bit(unsigned nr, volatile unsigned long *addr)
{
_atomic_xor(addr + BIT_WORD(nr), BIT_MASK(nr));
_atomic_fetch_xor(addr + BIT_WORD(nr), BIT_MASK(nr));
}
/**
@ -85,7 +85,7 @@ static inline int test_and_set_bit(unsigned nr, volatile unsigned long *addr)
unsigned long mask = BIT_MASK(nr);
addr += BIT_WORD(nr);
smp_mb(); /* barrier for proper semantics */
return (_atomic_or(addr, mask) & mask) != 0;
return (_atomic_fetch_or(addr, mask) & mask) != 0;
}
/**
@ -101,7 +101,7 @@ static inline int test_and_clear_bit(unsigned nr, volatile unsigned long *addr)
unsigned long mask = BIT_MASK(nr);
addr += BIT_WORD(nr);
smp_mb(); /* barrier for proper semantics */
return (_atomic_andn(addr, mask) & mask) != 0;
return (_atomic_fetch_andn(addr, mask) & mask) != 0;
}
/**
@ -118,7 +118,7 @@ static inline int test_and_change_bit(unsigned nr,
unsigned long mask = BIT_MASK(nr);
addr += BIT_WORD(nr);
smp_mb(); /* barrier for proper semantics */
return (_atomic_xor(addr, mask) & mask) != 0;
return (_atomic_fetch_xor(addr, mask) & mask) != 0;
}
#include <asm-generic/bitops/ext2-atomic.h>

14
arch/tile/include/asm/futex.h
View File

@ -80,16 +80,16 @@
ret = gu.err; \
}
#define __futex_set() __futex_call(__atomic_xchg)
#define __futex_add() __futex_call(__atomic_xchg_add)
#define __futex_or() __futex_call(__atomic_or)
#define __futex_andn() __futex_call(__atomic_andn)
#define __futex_xor() __futex_call(__atomic_xor)
#define __futex_set() __futex_call(__atomic32_xchg)
#define __futex_add() __futex_call(__atomic32_xchg_add)
#define __futex_or() __futex_call(__atomic32_fetch_or)
#define __futex_andn() __futex_call(__atomic32_fetch_andn)
#define __futex_xor() __futex_call(__atomic32_fetch_xor)
#define __futex_cmpxchg() \
{ \
struct __get_user gu = __atomic_cmpxchg((u32 __force *)uaddr, \
lock, oldval, oparg); \
struct __get_user gu = __atomic32_cmpxchg((u32 __force *)uaddr, \
lock, oldval, oparg); \
val = gu.val; \
ret = gu.err; \
}

50
arch/tile/lib/atomic_32.c
View File

@ -61,13 +61,13 @@ static inline int *__atomic_setup(volatile void *v)
int _atomic_xchg(int *v, int n)
{
return __atomic_xchg(v, __atomic_setup(v), n).val;
return __atomic32_xchg(v, __atomic_setup(v), n).val;
}
EXPORT_SYMBOL(_atomic_xchg);
int _atomic_xchg_add(int *v, int i)
{
return __atomic_xchg_add(v, __atomic_setup(v), i).val;
return __atomic32_xchg_add(v, __atomic_setup(v), i).val;
}
EXPORT_SYMBOL(_atomic_xchg_add);
@ -78,39 +78,39 @@ int _atomic_xchg_add_unless(int *v, int a, int u)
* to use the first argument consistently as the "old value"
* in the assembly, as is done for _atomic_cmpxchg().
*/
return __atomic_xchg_add_unless(v, __atomic_setup(v), u, a).val;
return __atomic32_xchg_add_unless(v, __atomic_setup(v), u, a).val;
}
EXPORT_SYMBOL(_atomic_xchg_add_unless);
int _atomic_cmpxchg(int *v, int o, int n)
{
return __atomic_cmpxchg(v, __atomic_setup(v), o, n).val;
return __atomic32_cmpxchg(v, __atomic_setup(v), o, n).val;
}
EXPORT_SYMBOL(_atomic_cmpxchg);
unsigned long _atomic_or(volatile unsigned long *p, unsigned long mask)
unsigned long _atomic_fetch_or(volatile unsigned long *p, unsigned long mask)
{
return __atomic_or((int *)p, __atomic_setup(p), mask).val;
return __atomic32_fetch_or((int *)p, __atomic_setup(p), mask).val;
}
EXPORT_SYMBOL(_atomic_or);
EXPORT_SYMBOL(_atomic_fetch_or);
unsigned long _atomic_and(volatile unsigned long *p, unsigned long mask)
unsigned long _atomic_fetch_and(volatile unsigned long *p, unsigned long mask)
{
return __atomic_and((int *)p, __atomic_setup(p), mask).val;
return __atomic32_fetch_and((int *)p, __atomic_setup(p), mask).val;
}
EXPORT_SYMBOL(_atomic_and);
EXPORT_SYMBOL(_atomic_fetch_and);
unsigned long _atomic_andn(volatile unsigned long *p, unsigned long mask)
unsigned long _atomic_fetch_andn(volatile unsigned long *p, unsigned long mask)
{
return __atomic_andn((int *)p, __atomic_setup(p), mask).val;
return __atomic32_fetch_andn((int *)p, __atomic_setup(p), mask).val;
}
EXPORT_SYMBOL(_atomic_andn);
EXPORT_SYMBOL(_atomic_fetch_andn);
unsigned long _atomic_xor(volatile unsigned long *p, unsigned long mask)
unsigned long _atomic_fetch_xor(volatile unsigned long *p, unsigned long mask)
{
return __atomic_xor((int *)p, __atomic_setup(p), mask).val;
return __atomic32_fetch_xor((int *)p, __atomic_setup(p), mask).val;
}
EXPORT_SYMBOL(_atomic_xor);
EXPORT_SYMBOL(_atomic_fetch_xor);
long long _atomic64_xchg(long long *v, long long n)
@ -142,23 +142,23 @@ long long _atomic64_cmpxchg(long long *v, long long o, long long n)
}
EXPORT_SYMBOL(_atomic64_cmpxchg);
long long _atomic64_and(long long *v, long long n)
long long _atomic64_fetch_and(long long *v, long long n)
{
return __atomic64_and(v, __atomic_setup(v), n);
return __atomic64_fetch_and(v, __atomic_setup(v), n);
}
EXPORT_SYMBOL(_atomic64_and);
EXPORT_SYMBOL(_atomic64_fetch_and);
long long _atomic64_or(long long *v, long long n)
long long _atomic64_fetch_or(long long *v, long long n)
{
return __atomic64_or(v, __atomic_setup(v), n);
return __atomic64_fetch_or(v, __atomic_setup(v), n);
}
EXPORT_SYMBOL(_atomic64_or);
EXPORT_SYMBOL(_atomic64_fetch_or);
long long _atomic64_xor(long long *v, long long n)
long long _atomic64_fetch_xor(long long *v, long long n)
{
return __atomic64_xor(v, __atomic_setup(v), n);
return __atomic64_fetch_xor(v, __atomic_setup(v), n);
}
EXPORT_SYMBOL(_atomic64_xor);
EXPORT_SYMBOL(_atomic64_fetch_xor);
/*
* If any of the atomic or futex routines hit a bad address (not in

27
arch/tile/lib/atomic_asm_32.S
View File

@ -172,15 +172,20 @@ STD_ENTRY_SECTION(__atomic\name, .text.atomic)
.endif
.endm
atomic_op _cmpxchg, 32, "seq r26, r22, r2; { bbns r26, 3f; move r24, r3 }"
atomic_op _xchg, 32, "move r24, r2"
atomic_op _xchg_add, 32, "add r24, r22, r2"
atomic_op _xchg_add_unless, 32, \
/*
* Use __atomic32 prefix to avoid collisions with GCC builtin __atomic functions.
*/
atomic_op 32_cmpxchg, 32, "seq r26, r22, r2; { bbns r26, 3f; move r24, r3 }"
atomic_op 32_xchg, 32, "move r24, r2"
atomic_op 32_xchg_add, 32, "add r24, r22, r2"
atomic_op 32_xchg_add_unless, 32, \
"sne r26, r22, r2; { bbns r26, 3f; add r24, r22, r3 }"
atomic_op _or, 32, "or r24, r22, r2"
atomic_op _and, 32, "and r24, r22, r2"
atomic_op _andn, 32, "nor r2, r2, zero; and r24, r22, r2"
atomic_op _xor, 32, "xor r24, r22, r2"
atomic_op 32_fetch_or, 32, "or r24, r22, r2"
atomic_op 32_fetch_and, 32, "and r24, r22, r2"
atomic_op 32_fetch_andn, 32, "nor r2, r2, zero; and r24, r22, r2"
atomic_op 32_fetch_xor, 32, "xor r24, r22, r2"
atomic_op 64_cmpxchg, 64, "{ seq r26, r22, r2; seq r27, r23, r3 }; \
{ bbns r26, 3f; move r24, r4 }; { bbns r27, 3f; move r25, r5 }"
@ -192,9 +197,9 @@ atomic_op 64_xchg_add_unless, 64, \
{ bbns r26, 3f; add r24, r22, r4 }; \
{ bbns r27, 3f; add r25, r23, r5 }; \
slt_u r26, r24, r22; add r25, r25, r26"
atomic_op 64_or, 64, "{ or r24, r22, r2; or r25, r23, r3 }"
atomic_op 64_and, 64, "{ and r24, r22, r2; and r25, r23, r3 }"
atomic_op 64_xor, 64, "{ xor r24, r22, r2; xor r25, r23, r3 }"
atomic_op 64_fetch_or, 64, "{ or r24, r22, r2; or r25, r23, r3 }"
atomic_op 64_fetch_and, 64, "{ and r24, r22, r2; and r25, r23, r3 }"
atomic_op 64_fetch_xor, 64, "{ xor r24, r22, r2; xor r25, r23, r3 }"
jrp lr /* happy backtracer */

6
arch/tile/lib/spinlock_32.c
View File

@ -76,6 +76,12 @@ void arch_spin_unlock_wait(arch_spinlock_t *lock)
do {
delay_backoff(iterations++);
} while (READ_ONCE(lock->current_ticket) == curr);
/*
* The TILE architecture doesn't do read speculation; therefore
* a control dependency guarantees a LOAD->{LOAD,STORE} order.
*/
barrier();
}
EXPORT_SYMBOL(arch_spin_unlock_wait);

6
arch/tile/lib/spinlock_64.c
View File

@ -76,6 +76,12 @@ void arch_spin_unlock_wait(arch_spinlock_t *lock)
do {
delay_backoff(iterations++);
} while (arch_spin_current(READ_ONCE(lock->lock)) == curr);
/*
* The TILE architecture doesn't do read speculation; therefore
* a control dependency guarantees a LOAD->{LOAD,STORE} order.
*/
barrier();
}
EXPORT_SYMBOL(arch_spin_unlock_wait);

35
arch/x86/include/asm/atomic.h
View File

@ -171,6 +171,16 @@ static __always_inline int atomic_sub_return(int i, atomic_t *v)
#define atomic_inc_return(v) (atomic_add_return(1, v))
#define atomic_dec_return(v) (atomic_sub_return(1, v))
static __always_inline int atomic_fetch_add(int i, atomic_t *v)
{
return xadd(&v->counter, i);
}
static __always_inline int atomic_fetch_sub(int i, atomic_t *v)
{
return xadd(&v->counter, -i);
}
static __always_inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
return cmpxchg(&v->counter, old, new);
@ -190,10 +200,29 @@ static inline void atomic_##op(int i, atomic_t *v) \
: "memory"); \
}
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int old, val = atomic_read(v); \
for (;;) { \
old = atomic_cmpxchg(v, val, val c_op i); \
if (old == val) \
break; \
val = old; \
} \
return old; \
}
#define ATOMIC_OPS(op, c_op) \
ATOMIC_OP(op) \
ATOMIC_FETCH_OP(op, c_op)
ATOMIC_OPS(and, &)
ATOMIC_OPS(or , |)
ATOMIC_OPS(xor, ^)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP
/**

25
arch/x86/include/asm/atomic64_32.h
View File

@ -320,10 +320,29 @@ static inline void atomic64_##op(long long i, atomic64_t *v) \
c = old; \
}
ATOMIC64_OP(and, &)
ATOMIC64_OP(or, |)
ATOMIC64_OP(xor, ^)
#define ATOMIC64_FETCH_OP(op, c_op) \
static inline long long atomic64_fetch_##op(long long i, atomic64_t *v) \
{ \
long long old, c = 0; \
while ((old = atomic64_cmpxchg(v, c, c c_op i)) != c) \
c = old; \
return old; \
}
ATOMIC64_FETCH_OP(add, +)
#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op, c_op) \
ATOMIC64_FETCH_OP(op, c_op)
ATOMIC64_OPS(and, &)
ATOMIC64_OPS(or, |)
ATOMIC64_OPS(xor, ^)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP
#endif /* _ASM_X86_ATOMIC64_32_H */

35
arch/x86/include/asm/atomic64_64.h
View File

@ -158,6 +158,16 @@ static inline long atomic64_sub_return(long i, atomic64_t *v)
return atomic64_add_return(-i, v);
}
static inline long atomic64_fetch_add(long i, atomic64_t *v)
{
return xadd(&v->counter, i);
}
static inline long atomic64_fetch_sub(long i, atomic64_t *v)
{
return xadd(&v->counter, -i);
}
#define atomic64_inc_return(v) (atomic64_add_return(1, (v)))
#define atomic64_dec_return(v) (atomic64_sub_return(1, (v)))
@ -229,10 +239,29 @@ static inline void atomic64_##op(long i, atomic64_t *v) \
: "memory"); \
}
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)
#define ATOMIC64_FETCH_OP(op, c_op) \
static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
{ \
long old, val = atomic64_read(v); \
for (;;) { \
old = atomic64_cmpxchg(v, val, val c_op i); \
if (old == val) \
break; \
val = old; \
} \
return old; \
}
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op) \
ATOMIC64_FETCH_OP(op, c_op)
ATOMIC64_OPS(and, &)
ATOMIC64_OPS(or, |)
ATOMIC64_OPS(xor, ^)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP
#endif /* _ASM_X86_ATOMIC64_64_H */

2
arch/x86/include/asm/mutex_32.h
View File

@ -101,7 +101,7 @@ static inline int __mutex_fastpath_trylock(atomic_t *count,
int (*fail_fn)(atomic_t *))
{
/* cmpxchg because it never induces a false contention state. */
if (likely(atomic_cmpxchg(count, 1, 0) == 1))
if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1))
return 1;
return 0;

6
arch/x86/include/asm/mutex_64.h
View File

@ -118,10 +118,10 @@ do { \
static inline int __mutex_fastpath_trylock(atomic_t *count,
int (*fail_fn)(atomic_t *))
{
if (likely(atomic_cmpxchg(count, 1, 0) == 1))
if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1))
return 1;
else
return 0;
return 0;
}
#endif /* _ASM_X86_MUTEX_64_H */

18
arch/x86/include/asm/rwsem.h
View File

@ -213,23 +213,5 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
: "memory", "cc");
}
/*
* implement atomic add functionality
*/
static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
{
asm volatile(LOCK_PREFIX _ASM_ADD "%1,%0"
: "+m" (sem->count)
: "er" (delta));
}
/*
* implement exchange and add functionality
*/
static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
{
return delta + xadd(&sem->count, delta);
}
#endif /* __KERNEL__ */
#endif /* _ASM_X86_RWSEM_H */

52
arch/xtensa/include/asm/atomic.h
View File

@ -98,6 +98,26 @@ static inline int atomic_##op##_return(int i, atomic_t * v) \
return result; \
}
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t * v) \
{ \
unsigned long tmp; \
int result; \
\
__asm__ __volatile__( \
"1: l32i %1, %3, 0\n" \
" wsr %1, scompare1\n" \
" " #op " %0, %1, %2\n" \
" s32c1i %0, %3, 0\n" \
" bne %0, %1, 1b\n" \
: "=&a" (result), "=&a" (tmp) \
: "a" (i), "a" (v) \
: "memory" \
); \
\
return result; \
}
#else /* XCHAL_HAVE_S32C1I */
#define ATOMIC_OP(op) \
@ -138,18 +158,42 @@ static inline int atomic_##op##_return(int i, atomic_t * v) \
return vval; \
}
#define ATOMIC_FETCH_OP(op) \
static inline int atomic_fetch_##op(int i, atomic_t * v) \
{ \
unsigned int tmp, vval; \
\
__asm__ __volatile__( \
" rsil a15,"__stringify(TOPLEVEL)"\n" \
" l32i %0, %3, 0\n" \
" " #op " %1, %0, %2\n" \
" s32i %1, %3, 0\n" \
" wsr a15, ps\n" \
" rsync\n" \
: "=&a" (vval), "=&a" (tmp) \
: "a" (i), "a" (v) \
: "a15", "memory" \
); \
\
return vval; \
}
#endif /* XCHAL_HAVE_S32C1I */
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) ATOMIC_OP_RETURN(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op)
ATOMIC_OPS(and)
ATOMIC_OPS(or)
ATOMIC_OPS(xor)
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

10
arch/xtensa/include/asm/spinlock.h
View File

@ -11,6 +11,9 @@
#ifndef _XTENSA_SPINLOCK_H
#define _XTENSA_SPINLOCK_H
#include <asm/barrier.h>
#include <asm/processor.h>
/*
* spinlock
*
@ -29,8 +32,11 @@
*/
#define arch_spin_is_locked(x) ((x)->slock != 0)
#define arch_spin_unlock_wait(lock) \
do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->slock, !VAL);
}
#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)

58
include/asm-generic/atomic-long.h
View File

@ -112,6 +112,62 @@ static __always_inline void atomic_long_dec(atomic_long_t *l)
ATOMIC_LONG_PFX(_dec)(v);
}
#define ATOMIC_LONG_FETCH_OP(op, mo) \
static inline long \
atomic_long_fetch_##op##mo(long i, atomic_long_t *l) \
{ \
ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; \
\
return (long)ATOMIC_LONG_PFX(_fetch_##op##mo)(i, v); \
}
ATOMIC_LONG_FETCH_OP(add, )
ATOMIC_LONG_FETCH_OP(add, _relaxed)
ATOMIC_LONG_FETCH_OP(add, _acquire)
ATOMIC_LONG_FETCH_OP(add, _release)
ATOMIC_LONG_FETCH_OP(sub, )
ATOMIC_LONG_FETCH_OP(sub, _relaxed)
ATOMIC_LONG_FETCH_OP(sub, _acquire)
ATOMIC_LONG_FETCH_OP(sub, _release)
ATOMIC_LONG_FETCH_OP(and, )
ATOMIC_LONG_FETCH_OP(and, _relaxed)
ATOMIC_LONG_FETCH_OP(and, _acquire)
ATOMIC_LONG_FETCH_OP(and, _release)
ATOMIC_LONG_FETCH_OP(andnot, )
ATOMIC_LONG_FETCH_OP(andnot, _relaxed)
ATOMIC_LONG_FETCH_OP(andnot, _acquire)
ATOMIC_LONG_FETCH_OP(andnot, _release)
ATOMIC_LONG_FETCH_OP(or, )
ATOMIC_LONG_FETCH_OP(or, _relaxed)
ATOMIC_LONG_FETCH_OP(or, _acquire)
ATOMIC_LONG_FETCH_OP(or, _release)
ATOMIC_LONG_FETCH_OP(xor, )
ATOMIC_LONG_FETCH_OP(xor, _relaxed)
ATOMIC_LONG_FETCH_OP(xor, _acquire)
ATOMIC_LONG_FETCH_OP(xor, _release)
#undef ATOMIC_LONG_FETCH_OP
#define ATOMIC_LONG_FETCH_INC_DEC_OP(op, mo) \
static inline long \
atomic_long_fetch_##op##mo(atomic_long_t *l) \
{ \
ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l; \
\
return (long)ATOMIC_LONG_PFX(_fetch_##op##mo)(v); \
}
ATOMIC_LONG_FETCH_INC_DEC_OP(inc,)
ATOMIC_LONG_FETCH_INC_DEC_OP(inc, _relaxed)
ATOMIC_LONG_FETCH_INC_DEC_OP(inc, _acquire)
ATOMIC_LONG_FETCH_INC_DEC_OP(inc, _release)
ATOMIC_LONG_FETCH_INC_DEC_OP(dec,)
ATOMIC_LONG_FETCH_INC_DEC_OP(dec, _relaxed)
ATOMIC_LONG_FETCH_INC_DEC_OP(dec, _acquire)
ATOMIC_LONG_FETCH_INC_DEC_OP(dec, _release)
#undef ATOMIC_LONG_FETCH_INC_DEC_OP
#define ATOMIC_LONG_OP(op) \
static __always_inline void \
atomic_long_##op(long i, atomic_long_t *l) \
@ -124,9 +180,9 @@ atomic_long_##op(long i, atomic_long_t *l) \
ATOMIC_LONG_OP(add)
ATOMIC_LONG_OP(sub)
ATOMIC_LONG_OP(and)
ATOMIC_LONG_OP(andnot)
ATOMIC_LONG_OP(or)
ATOMIC_LONG_OP(xor)
ATOMIC_LONG_OP(andnot)
#undef ATOMIC_LONG_OP

47
include/asm-generic/atomic.h
View File

@ -61,6 +61,18 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return c c_op i; \
}
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
int c, old; \
\
c = v->counter; \
while ((old = cmpxchg(&v->counter, c, c c_op i)) != c) \
c = old; \
\
return c; \
}
#else
#include <linux/irqflags.h>
@ -88,6 +100,20 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \
return ret; \
}
#define ATOMIC_FETCH_OP(op, c_op) \
static inline int atomic_fetch_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
int ret; \
\
raw_local_irq_save(flags); \
ret = v->counter; \
v->counter = v->counter c_op i; \
raw_local_irq_restore(flags); \
\
return ret; \
}
#endif /* CONFIG_SMP */
#ifndef atomic_add_return
@ -98,6 +124,26 @@ ATOMIC_OP_RETURN(add, +)
ATOMIC_OP_RETURN(sub, -)
#endif
#ifndef atomic_fetch_add
ATOMIC_FETCH_OP(add, +)
#endif
#ifndef atomic_fetch_sub
ATOMIC_FETCH_OP(sub, -)
#endif
#ifndef atomic_fetch_and
ATOMIC_FETCH_OP(and, &)
#endif
#ifndef atomic_fetch_or
ATOMIC_FETCH_OP(or, |)
#endif
#ifndef atomic_fetch_xor
ATOMIC_FETCH_OP(xor, ^)
#endif
#ifndef atomic_and
ATOMIC_OP(and, &)
#endif
@ -110,6 +156,7 @@ ATOMIC_OP(or, |)
ATOMIC_OP(xor, ^)
#endif
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

15
include/asm-generic/atomic64.h
View File

@ -27,16 +27,23 @@ extern void atomic64_##op(long long a, atomic64_t *v);
#define ATOMIC64_OP_RETURN(op) \
extern long long atomic64_##op##_return(long long a, atomic64_t *v);
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op)
#define ATOMIC64_FETCH_OP(op) \
extern long long atomic64_fetch_##op(long long a, atomic64_t *v);
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) ATOMIC64_FETCH_OP(op)
ATOMIC64_OPS(add)
ATOMIC64_OPS(sub)
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_FETCH_OP(op)
ATOMIC64_OPS(and)
ATOMIC64_OPS(or)
ATOMIC64_OPS(xor)
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

41
include/asm-generic/barrier.h
View File

@ -194,7 +194,7 @@ do { \
})
#endif
#endif
#endif /* CONFIG_SMP */
/* Barriers for virtual machine guests when talking to an SMP host */
#define virt_mb() __smp_mb()
@ -207,5 +207,44 @@ do { \
#define virt_store_release(p, v) __smp_store_release(p, v)
#define virt_load_acquire(p) __smp_load_acquire(p)
/**
* smp_acquire__after_ctrl_dep() - Provide ACQUIRE ordering after a control dependency
*
* A control dependency provides a LOAD->STORE order, the additional RMB
* provides LOAD->LOAD order, together they provide LOAD->{LOAD,STORE} order,
* aka. (load)-ACQUIRE.
*
* Architectures that do not do load speculation can have this be barrier().
*/
#ifndef smp_acquire__after_ctrl_dep
#define smp_acquire__after_ctrl_dep() smp_rmb()
#endif
/**
* smp_cond_load_acquire() - (Spin) wait for cond with ACQUIRE ordering
* @ptr: pointer to the variable to wait on
* @cond: boolean expression to wait for
*
* Equivalent to using smp_load_acquire() on the condition variable but employs
* the control dependency of the wait to reduce the barrier on many platforms.
*
* Due to C lacking lambda expressions we load the value of *ptr into a
* pre-named variable @VAL to be used in @cond.
*/
#ifndef smp_cond_load_acquire
#define smp_cond_load_acquire(ptr, cond_expr) ({ \
typeof(ptr) __PTR = (ptr); \
typeof(*ptr) VAL; \
for (;;) { \
VAL = READ_ONCE(*__PTR); \
if (cond_expr) \
break; \
cpu_relax(); \
} \
smp_acquire__after_ctrl_dep(); \
VAL; \
})
#endif
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_GENERIC_BARRIER_H */

2
include/asm-generic/mutex-dec.h
View File

@ -80,7 +80,7 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
static inline int
__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
{
if (likely(atomic_cmpxchg_acquire(count, 1, 0) == 1))
if (likely(atomic_read(count) == 1 && atomic_cmpxchg_acquire(count, 1, 0) == 1))
return 1;
return 0;
}

6
include/asm-generic/mutex-xchg.h
View File

@ -91,8 +91,12 @@ __mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
static inline int
__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
{
int prev = atomic_xchg_acquire(count, 0);
int prev;
if (atomic_read(count) != 1)
return 0;
prev = atomic_xchg_acquire(count, 0);
if (unlikely(prev < 0)) {
/*
* The lock was marked contended so we must restore that

5
include/asm-generic/qspinlock.h
View File

@ -111,10 +111,9 @@ static __always_inline void queued_spin_lock(struct qspinlock *lock)
static __always_inline void queued_spin_unlock(struct qspinlock *lock)
{
/*
* smp_mb__before_atomic() in order to guarantee release semantics
* unlock() needs release semantics:
*/
smp_mb__before_atomic();
atomic_sub(_Q_LOCKED_VAL, &lock->val);
(void)atomic_sub_return_release(_Q_LOCKED_VAL, &lock->val);
}
#endif

22
include/asm-generic/rwsem.h
View File

@ -41,8 +41,8 @@ static inline int __down_read_trylock(struct rw_semaphore *sem)
{
long tmp;
while ((tmp = sem->count) >= 0) {
if (tmp == cmpxchg_acquire(&sem->count, tmp,
while ((tmp = atomic_long_read(&sem->count)) >= 0) {
if (tmp == atomic_long_cmpxchg_acquire(&sem->count, tmp,
tmp + RWSEM_ACTIVE_READ_BIAS)) {
return 1;
}
@ -79,7 +79,7 @@ static inline int __down_write_trylock(struct rw_semaphore *sem)
{
long tmp;
tmp = cmpxchg_acquire(&sem->count, RWSEM_UNLOCKED_VALUE,
tmp = atomic_long_cmpxchg_acquire(&sem->count, RWSEM_UNLOCKED_VALUE,
RWSEM_ACTIVE_WRITE_BIAS);
return tmp == RWSEM_UNLOCKED_VALUE;
}
@ -106,14 +106,6 @@ static inline void __up_write(struct rw_semaphore *sem)
rwsem_wake(sem);
}
/*
* implement atomic add functionality
*/
static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
{
atomic_long_add(delta, (atomic_long_t *)&sem->count);
}
/*
* downgrade write lock to read lock
*/
@ -134,13 +126,5 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
rwsem_downgrade_wake(sem);
}
/*
* implement exchange and add functionality
*/
static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
{
return atomic_long_add_return(delta, (atomic_long_t *)&sem->count);
}
#endif /* __KERNEL__ */
#endif /* _ASM_GENERIC_RWSEM_H */

871
include/linux/atomic.h
View File

@ -163,6 +163,218 @@
#endif
#endif /* atomic_dec_return_relaxed */
/* atomic_fetch_add_relaxed */
#ifndef atomic_fetch_add_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add
#define atomic_fetch_add_acquire atomic_fetch_add
#define atomic_fetch_add_release atomic_fetch_add
#else /* atomic_fetch_add_relaxed */
#ifndef atomic_fetch_add_acquire
#define atomic_fetch_add_acquire(...) \
__atomic_op_acquire(atomic_fetch_add, __VA_ARGS__)
#endif
#ifndef atomic_fetch_add_release
#define atomic_fetch_add_release(...) \
__atomic_op_release(atomic_fetch_add, __VA_ARGS__)
#endif
#ifndef atomic_fetch_add
#define atomic_fetch_add(...) \
__atomic_op_fence(atomic_fetch_add, __VA_ARGS__)
#endif
#endif /* atomic_fetch_add_relaxed */
/* atomic_fetch_inc_relaxed */
#ifndef atomic_fetch_inc_relaxed
#ifndef atomic_fetch_inc
#define atomic_fetch_inc(v) atomic_fetch_add(1, (v))
#define atomic_fetch_inc_relaxed(v) atomic_fetch_add_relaxed(1, (v))
#define atomic_fetch_inc_acquire(v) atomic_fetch_add_acquire(1, (v))
#define atomic_fetch_inc_release(v) atomic_fetch_add_release(1, (v))
#else /* atomic_fetch_inc */
#define atomic_fetch_inc_relaxed atomic_fetch_inc
#define atomic_fetch_inc_acquire atomic_fetch_inc
#define atomic_fetch_inc_release atomic_fetch_inc
#endif /* atomic_fetch_inc */
#else /* atomic_fetch_inc_relaxed */
#ifndef atomic_fetch_inc_acquire
#define atomic_fetch_inc_acquire(...) \
__atomic_op_acquire(atomic_fetch_inc, __VA_ARGS__)
#endif
#ifndef atomic_fetch_inc_release
#define atomic_fetch_inc_release(...) \
__atomic_op_release(atomic_fetch_inc, __VA_ARGS__)
#endif
#ifndef atomic_fetch_inc
#define atomic_fetch_inc(...) \
__atomic_op_fence(atomic_fetch_inc, __VA_ARGS__)
#endif
#endif /* atomic_fetch_inc_relaxed */
/* atomic_fetch_sub_relaxed */
#ifndef atomic_fetch_sub_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub
#define atomic_fetch_sub_acquire atomic_fetch_sub
#define atomic_fetch_sub_release atomic_fetch_sub
#else /* atomic_fetch_sub_relaxed */
#ifndef atomic_fetch_sub_acquire
#define atomic_fetch_sub_acquire(...) \
__atomic_op_acquire(atomic_fetch_sub, __VA_ARGS__)
#endif
#ifndef atomic_fetch_sub_release
#define atomic_fetch_sub_release(...) \
__atomic_op_release(atomic_fetch_sub, __VA_ARGS__)
#endif
#ifndef atomic_fetch_sub
#define atomic_fetch_sub(...) \
__atomic_op_fence(atomic_fetch_sub, __VA_ARGS__)
#endif
#endif /* atomic_fetch_sub_relaxed */
/* atomic_fetch_dec_relaxed */
#ifndef atomic_fetch_dec_relaxed
#ifndef atomic_fetch_dec
#define atomic_fetch_dec(v) atomic_fetch_sub(1, (v))
#define atomic_fetch_dec_relaxed(v) atomic_fetch_sub_relaxed(1, (v))
#define atomic_fetch_dec_acquire(v) atomic_fetch_sub_acquire(1, (v))
#define atomic_fetch_dec_release(v) atomic_fetch_sub_release(1, (v))
#else /* atomic_fetch_dec */
#define atomic_fetch_dec_relaxed atomic_fetch_dec
#define atomic_fetch_dec_acquire atomic_fetch_dec
#define atomic_fetch_dec_release atomic_fetch_dec
#endif /* atomic_fetch_dec */
#else /* atomic_fetch_dec_relaxed */
#ifndef atomic_fetch_dec_acquire
#define atomic_fetch_dec_acquire(...) \
__atomic_op_acquire(atomic_fetch_dec, __VA_ARGS__)
#endif
#ifndef atomic_fetch_dec_release
#define atomic_fetch_dec_release(...) \
__atomic_op_release(atomic_fetch_dec, __VA_ARGS__)
#endif
#ifndef atomic_fetch_dec
#define atomic_fetch_dec(...) \
__atomic_op_fence(atomic_fetch_dec, __VA_ARGS__)
#endif
#endif /* atomic_fetch_dec_relaxed */
/* atomic_fetch_or_relaxed */
#ifndef atomic_fetch_or_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or
#define atomic_fetch_or_acquire atomic_fetch_or
#define atomic_fetch_or_release atomic_fetch_or
#else /* atomic_fetch_or_relaxed */
#ifndef atomic_fetch_or_acquire
#define atomic_fetch_or_acquire(...) \
__atomic_op_acquire(atomic_fetch_or, __VA_ARGS__)
#endif
#ifndef atomic_fetch_or_release
#define atomic_fetch_or_release(...) \
__atomic_op_release(atomic_fetch_or, __VA_ARGS__)
#endif
#ifndef atomic_fetch_or
#define atomic_fetch_or(...) \
__atomic_op_fence(atomic_fetch_or, __VA_ARGS__)
#endif
#endif /* atomic_fetch_or_relaxed */
/* atomic_fetch_and_relaxed */
#ifndef atomic_fetch_and_relaxed
#define atomic_fetch_and_relaxed atomic_fetch_and
#define atomic_fetch_and_acquire atomic_fetch_and
#define atomic_fetch_and_release atomic_fetch_and
#else /* atomic_fetch_and_relaxed */
#ifndef atomic_fetch_and_acquire
#define atomic_fetch_and_acquire(...) \
__atomic_op_acquire(atomic_fetch_and, __VA_ARGS__)
#endif
#ifndef atomic_fetch_and_release
#define atomic_fetch_and_release(...) \
__atomic_op_release(atomic_fetch_and, __VA_ARGS__)
#endif
#ifndef atomic_fetch_and
#define atomic_fetch_and(...) \
__atomic_op_fence(atomic_fetch_and, __VA_ARGS__)
#endif
#endif /* atomic_fetch_and_relaxed */
#ifdef atomic_andnot
/* atomic_fetch_andnot_relaxed */
#ifndef atomic_fetch_andnot_relaxed
#define atomic_fetch_andnot_relaxed atomic_fetch_andnot
#define atomic_fetch_andnot_acquire atomic_fetch_andnot
#define atomic_fetch_andnot_release atomic_fetch_andnot
#else /* atomic_fetch_andnot_relaxed */
#ifndef atomic_fetch_andnot_acquire
#define atomic_fetch_andnot_acquire(...) \
__atomic_op_acquire(atomic_fetch_andnot, __VA_ARGS__)
#endif
#ifndef atomic_fetch_andnot_release
#define atomic_fetch_andnot_release(...) \
__atomic_op_release(atomic_fetch_andnot, __VA_ARGS__)
#endif
#ifndef atomic_fetch_andnot
#define atomic_fetch_andnot(...) \
__atomic_op_fence(atomic_fetch_andnot, __VA_ARGS__)
#endif
#endif /* atomic_fetch_andnot_relaxed */
#endif /* atomic_andnot */
/* atomic_fetch_xor_relaxed */
#ifndef atomic_fetch_xor_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor
#define atomic_fetch_xor_acquire atomic_fetch_xor
#define atomic_fetch_xor_release atomic_fetch_xor
#else /* atomic_fetch_xor_relaxed */
#ifndef atomic_fetch_xor_acquire
#define atomic_fetch_xor_acquire(...) \
__atomic_op_acquire(atomic_fetch_xor, __VA_ARGS__)
#endif
#ifndef atomic_fetch_xor_release
#define atomic_fetch_xor_release(...) \
__atomic_op_release(atomic_fetch_xor, __VA_ARGS__)
#endif
#ifndef atomic_fetch_xor
#define atomic_fetch_xor(...) \
__atomic_op_fence(atomic_fetch_xor, __VA_ARGS__)
#endif
#endif /* atomic_fetch_xor_relaxed */
/* atomic_xchg_relaxed */
#ifndef atomic_xchg_relaxed
#define atomic_xchg_relaxed atomic_xchg
@ -211,6 +423,214 @@
#endif
#endif /* atomic_cmpxchg_relaxed */
/* cmpxchg_relaxed */
#ifndef cmpxchg_relaxed
#define cmpxchg_relaxed cmpxchg
#define cmpxchg_acquire cmpxchg
#define cmpxchg_release cmpxchg
#else /* cmpxchg_relaxed */
#ifndef cmpxchg_acquire
#define cmpxchg_acquire(...) \
__atomic_op_acquire(cmpxchg, __VA_ARGS__)
#endif
#ifndef cmpxchg_release
#define cmpxchg_release(...) \
__atomic_op_release(cmpxchg, __VA_ARGS__)
#endif
#ifndef cmpxchg
#define cmpxchg(...) \
__atomic_op_fence(cmpxchg, __VA_ARGS__)
#endif
#endif /* cmpxchg_relaxed */
/* cmpxchg64_relaxed */
#ifndef cmpxchg64_relaxed
#define cmpxchg64_relaxed cmpxchg64
#define cmpxchg64_acquire cmpxchg64
#define cmpxchg64_release cmpxchg64
#else /* cmpxchg64_relaxed */
#ifndef cmpxchg64_acquire
#define cmpxchg64_acquire(...) \
__atomic_op_acquire(cmpxchg64, __VA_ARGS__)
#endif
#ifndef cmpxchg64_release
#define cmpxchg64_release(...) \
__atomic_op_release(cmpxchg64, __VA_ARGS__)
#endif
#ifndef cmpxchg64
#define cmpxchg64(...) \
__atomic_op_fence(cmpxchg64, __VA_ARGS__)
#endif
#endif /* cmpxchg64_relaxed */
/* xchg_relaxed */
#ifndef xchg_relaxed
#define xchg_relaxed xchg
#define xchg_acquire xchg
#define xchg_release xchg
#else /* xchg_relaxed */
#ifndef xchg_acquire
#define xchg_acquire(...) __atomic_op_acquire(xchg, __VA_ARGS__)
#endif
#ifndef xchg_release
#define xchg_release(...) __atomic_op_release(xchg, __VA_ARGS__)
#endif
#ifndef xchg
#define xchg(...) __atomic_op_fence(xchg, __VA_ARGS__)
#endif
#endif /* xchg_relaxed */
/**
* atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
return __atomic_add_unless(v, a, u) != u;
}
/**
* atomic_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1, so long as @v is non-zero.
* Returns non-zero if @v was non-zero, and zero otherwise.
*/
#ifndef atomic_inc_not_zero
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
#endif
#ifndef atomic_andnot
static inline void atomic_andnot(int i, atomic_t *v)
{
atomic_and(~i, v);
}
static inline int atomic_fetch_andnot(int i, atomic_t *v)
{
return atomic_fetch_and(~i, v);
}
static inline int atomic_fetch_andnot_relaxed(int i, atomic_t *v)
{
return atomic_fetch_and_relaxed(~i, v);
}
static inline int atomic_fetch_andnot_acquire(int i, atomic_t *v)
{
return atomic_fetch_and_acquire(~i, v);
}
static inline int atomic_fetch_andnot_release(int i, atomic_t *v)
{
return atomic_fetch_and_release(~i, v);
}
#endif
/**
* atomic_inc_not_zero_hint - increment if not null
* @v: pointer of type atomic_t
* @hint: probable value of the atomic before the increment
*
* This version of atomic_inc_not_zero() gives a hint of probable
* value of the atomic. This helps processor to not read the memory
* before doing the atomic read/modify/write cycle, lowering
* number of bus transactions on some arches.
*
* Returns: 0 if increment was not done, 1 otherwise.
*/
#ifndef atomic_inc_not_zero_hint
static inline int atomic_inc_not_zero_hint(atomic_t *v, int hint)
{
int val, c = hint;
/* sanity test, should be removed by compiler if hint is a constant */
if (!hint)
return atomic_inc_not_zero(v);
do {
val = atomic_cmpxchg(v, c, c + 1);
if (val == c)
return 1;
c = val;
} while (c);
return 0;
}
#endif
#ifndef atomic_inc_unless_negative
static inline int atomic_inc_unless_negative(atomic_t *p)
{
int v, v1;
for (v = 0; v >= 0; v = v1) {
v1 = atomic_cmpxchg(p, v, v + 1);
if (likely(v1 == v))
return 1;
}
return 0;
}
#endif
#ifndef atomic_dec_unless_positive
static inline int atomic_dec_unless_positive(atomic_t *p)
{
int v, v1;
for (v = 0; v <= 0; v = v1) {
v1 = atomic_cmpxchg(p, v, v - 1);
if (likely(v1 == v))
return 1;
}
return 0;
}
#endif
/*
* atomic_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic_t
*
* The function returns the old value of *v minus 1, even if
* the atomic variable, v, was not decremented.
*/
#ifndef atomic_dec_if_positive
static inline int atomic_dec_if_positive(atomic_t *v)
{
int c, old, dec;
c = atomic_read(v);
for (;;) {
dec = c - 1;
if (unlikely(dec < 0))
break;
old = atomic_cmpxchg((v), c, dec);
if (likely(old == c))
break;
c = old;
}
return dec;
}
#endif
#ifdef CONFIG_GENERIC_ATOMIC64
#include <asm-generic/atomic64.h>
#endif
#ifndef atomic64_read_acquire
#define atomic64_read_acquire(v) smp_load_acquire(&(v)->counter)
#endif
@ -316,6 +736,218 @@
#endif
#endif /* atomic64_dec_return_relaxed */
/* atomic64_fetch_add_relaxed */
#ifndef atomic64_fetch_add_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add
#define atomic64_fetch_add_acquire atomic64_fetch_add
#define atomic64_fetch_add_release atomic64_fetch_add
#else /* atomic64_fetch_add_relaxed */
#ifndef atomic64_fetch_add_acquire
#define atomic64_fetch_add_acquire(...) \
__atomic_op_acquire(atomic64_fetch_add, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_add_release
#define atomic64_fetch_add_release(...) \
__atomic_op_release(atomic64_fetch_add, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_add
#define atomic64_fetch_add(...) \
__atomic_op_fence(atomic64_fetch_add, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_add_relaxed */
/* atomic64_fetch_inc_relaxed */
#ifndef atomic64_fetch_inc_relaxed
#ifndef atomic64_fetch_inc
#define atomic64_fetch_inc(v) atomic64_fetch_add(1, (v))
#define atomic64_fetch_inc_relaxed(v) atomic64_fetch_add_relaxed(1, (v))
#define atomic64_fetch_inc_acquire(v) atomic64_fetch_add_acquire(1, (v))
#define atomic64_fetch_inc_release(v) atomic64_fetch_add_release(1, (v))
#else /* atomic64_fetch_inc */
#define atomic64_fetch_inc_relaxed atomic64_fetch_inc
#define atomic64_fetch_inc_acquire atomic64_fetch_inc
#define atomic64_fetch_inc_release atomic64_fetch_inc
#endif /* atomic64_fetch_inc */
#else /* atomic64_fetch_inc_relaxed */
#ifndef atomic64_fetch_inc_acquire
#define atomic64_fetch_inc_acquire(...) \
__atomic_op_acquire(atomic64_fetch_inc, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_inc_release
#define atomic64_fetch_inc_release(...) \
__atomic_op_release(atomic64_fetch_inc, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_inc
#define atomic64_fetch_inc(...) \
__atomic_op_fence(atomic64_fetch_inc, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_inc_relaxed */
/* atomic64_fetch_sub_relaxed */
#ifndef atomic64_fetch_sub_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub
#define atomic64_fetch_sub_acquire atomic64_fetch_sub
#define atomic64_fetch_sub_release atomic64_fetch_sub
#else /* atomic64_fetch_sub_relaxed */
#ifndef atomic64_fetch_sub_acquire
#define atomic64_fetch_sub_acquire(...) \
__atomic_op_acquire(atomic64_fetch_sub, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_sub_release
#define atomic64_fetch_sub_release(...) \
__atomic_op_release(atomic64_fetch_sub, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_sub
#define atomic64_fetch_sub(...) \
__atomic_op_fence(atomic64_fetch_sub, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_sub_relaxed */
/* atomic64_fetch_dec_relaxed */
#ifndef atomic64_fetch_dec_relaxed
#ifndef atomic64_fetch_dec
#define atomic64_fetch_dec(v) atomic64_fetch_sub(1, (v))
#define atomic64_fetch_dec_relaxed(v) atomic64_fetch_sub_relaxed(1, (v))
#define atomic64_fetch_dec_acquire(v) atomic64_fetch_sub_acquire(1, (v))
#define atomic64_fetch_dec_release(v) atomic64_fetch_sub_release(1, (v))
#else /* atomic64_fetch_dec */
#define atomic64_fetch_dec_relaxed atomic64_fetch_dec
#define atomic64_fetch_dec_acquire atomic64_fetch_dec
#define atomic64_fetch_dec_release atomic64_fetch_dec
#endif /* atomic64_fetch_dec */
#else /* atomic64_fetch_dec_relaxed */
#ifndef atomic64_fetch_dec_acquire
#define atomic64_fetch_dec_acquire(...) \
__atomic_op_acquire(atomic64_fetch_dec, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_dec_release
#define atomic64_fetch_dec_release(...) \
__atomic_op_release(atomic64_fetch_dec, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_dec
#define atomic64_fetch_dec(...) \
__atomic_op_fence(atomic64_fetch_dec, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_dec_relaxed */
/* atomic64_fetch_or_relaxed */
#ifndef atomic64_fetch_or_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or
#define atomic64_fetch_or_acquire atomic64_fetch_or
#define atomic64_fetch_or_release atomic64_fetch_or
#else /* atomic64_fetch_or_relaxed */
#ifndef atomic64_fetch_or_acquire
#define atomic64_fetch_or_acquire(...) \
__atomic_op_acquire(atomic64_fetch_or, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_or_release
#define atomic64_fetch_or_release(...) \
__atomic_op_release(atomic64_fetch_or, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_or
#define atomic64_fetch_or(...) \
__atomic_op_fence(atomic64_fetch_or, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_or_relaxed */
/* atomic64_fetch_and_relaxed */
#ifndef atomic64_fetch_and_relaxed
#define atomic64_fetch_and_relaxed atomic64_fetch_and
#define atomic64_fetch_and_acquire atomic64_fetch_and
#define atomic64_fetch_and_release atomic64_fetch_and
#else /* atomic64_fetch_and_relaxed */
#ifndef atomic64_fetch_and_acquire
#define atomic64_fetch_and_acquire(...) \
__atomic_op_acquire(atomic64_fetch_and, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_and_release
#define atomic64_fetch_and_release(...) \
__atomic_op_release(atomic64_fetch_and, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_and
#define atomic64_fetch_and(...) \
__atomic_op_fence(atomic64_fetch_and, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_and_relaxed */
#ifdef atomic64_andnot
/* atomic64_fetch_andnot_relaxed */
#ifndef atomic64_fetch_andnot_relaxed
#define atomic64_fetch_andnot_relaxed atomic64_fetch_andnot
#define atomic64_fetch_andnot_acquire atomic64_fetch_andnot
#define atomic64_fetch_andnot_release atomic64_fetch_andnot
#else /* atomic64_fetch_andnot_relaxed */
#ifndef atomic64_fetch_andnot_acquire
#define atomic64_fetch_andnot_acquire(...) \
__atomic_op_acquire(atomic64_fetch_andnot, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_andnot_release
#define atomic64_fetch_andnot_release(...) \
__atomic_op_release(atomic64_fetch_andnot, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_andnot
#define atomic64_fetch_andnot(...) \
__atomic_op_fence(atomic64_fetch_andnot, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_andnot_relaxed */
#endif /* atomic64_andnot */
/* atomic64_fetch_xor_relaxed */
#ifndef atomic64_fetch_xor_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor
#define atomic64_fetch_xor_acquire atomic64_fetch_xor
#define atomic64_fetch_xor_release atomic64_fetch_xor
#else /* atomic64_fetch_xor_relaxed */
#ifndef atomic64_fetch_xor_acquire
#define atomic64_fetch_xor_acquire(...) \
__atomic_op_acquire(atomic64_fetch_xor, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_xor_release
#define atomic64_fetch_xor_release(...) \
__atomic_op_release(atomic64_fetch_xor, __VA_ARGS__)
#endif
#ifndef atomic64_fetch_xor
#define atomic64_fetch_xor(...) \
__atomic_op_fence(atomic64_fetch_xor, __VA_ARGS__)
#endif
#endif /* atomic64_fetch_xor_relaxed */
/* atomic64_xchg_relaxed */
#ifndef atomic64_xchg_relaxed
#define atomic64_xchg_relaxed atomic64_xchg
@ -364,230 +996,31 @@
#endif
#endif /* atomic64_cmpxchg_relaxed */
/* cmpxchg_relaxed */
#ifndef cmpxchg_relaxed
#define cmpxchg_relaxed cmpxchg
#define cmpxchg_acquire cmpxchg
#define cmpxchg_release cmpxchg
#else /* cmpxchg_relaxed */
#ifndef cmpxchg_acquire
#define cmpxchg_acquire(...) \
__atomic_op_acquire(cmpxchg, __VA_ARGS__)
#endif
#ifndef cmpxchg_release
#define cmpxchg_release(...) \
__atomic_op_release(cmpxchg, __VA_ARGS__)
#endif
#ifndef cmpxchg
#define cmpxchg(...) \
__atomic_op_fence(cmpxchg, __VA_ARGS__)
#endif
#endif /* cmpxchg_relaxed */
/* cmpxchg64_relaxed */
#ifndef cmpxchg64_relaxed
#define cmpxchg64_relaxed cmpxchg64
#define cmpxchg64_acquire cmpxchg64
#define cmpxchg64_release cmpxchg64
#else /* cmpxchg64_relaxed */
#ifndef cmpxchg64_acquire
#define cmpxchg64_acquire(...) \
__atomic_op_acquire(cmpxchg64, __VA_ARGS__)
#endif
#ifndef cmpxchg64_release
#define cmpxchg64_release(...) \
__atomic_op_release(cmpxchg64, __VA_ARGS__)
#endif
#ifndef cmpxchg64
#define cmpxchg64(...) \
__atomic_op_fence(cmpxchg64, __VA_ARGS__)
#endif
#endif /* cmpxchg64_relaxed */
/* xchg_relaxed */
#ifndef xchg_relaxed
#define xchg_relaxed xchg
#define xchg_acquire xchg
#define xchg_release xchg
#else /* xchg_relaxed */
#ifndef xchg_acquire
#define xchg_acquire(...) __atomic_op_acquire(xchg, __VA_ARGS__)
#endif
#ifndef xchg_release
#define xchg_release(...) __atomic_op_release(xchg, __VA_ARGS__)
#endif
#ifndef xchg
#define xchg(...) __atomic_op_fence(xchg, __VA_ARGS__)
#endif
#endif /* xchg_relaxed */
/**
* atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
return __atomic_add_unless(v, a, u) != u;
}
/**
* atomic_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1, so long as @v is non-zero.
* Returns non-zero if @v was non-zero, and zero otherwise.
*/
#ifndef atomic_inc_not_zero
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
#endif
#ifndef atomic_andnot
static inline void atomic_andnot(int i, atomic_t *v)
{
atomic_and(~i, v);
}
#endif
static inline __deprecated void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
atomic_andnot(mask, v);
}
static inline __deprecated void atomic_set_mask(unsigned int mask, atomic_t *v)
{
atomic_or(mask, v);
}
/**
* atomic_inc_not_zero_hint - increment if not null
* @v: pointer of type atomic_t
* @hint: probable value of the atomic before the increment
*
* This version of atomic_inc_not_zero() gives a hint of probable
* value of the atomic. This helps processor to not read the memory
* before doing the atomic read/modify/write cycle, lowering
* number of bus transactions on some arches.
*
* Returns: 0 if increment was not done, 1 otherwise.
*/
#ifndef atomic_inc_not_zero_hint
static inline int atomic_inc_not_zero_hint(atomic_t *v, int hint)
{
int val, c = hint;
/* sanity test, should be removed by compiler if hint is a constant */
if (!hint)
return atomic_inc_not_zero(v);
do {
val = atomic_cmpxchg(v, c, c + 1);
if (val == c)
return 1;
c = val;
} while (c);
return 0;
}
#endif
#ifndef atomic_inc_unless_negative
static inline int atomic_inc_unless_negative(atomic_t *p)
{
int v, v1;
for (v = 0; v >= 0; v = v1) {
v1 = atomic_cmpxchg(p, v, v + 1);
if (likely(v1 == v))
return 1;
}
return 0;
}
#endif
#ifndef atomic_dec_unless_positive
static inline int atomic_dec_unless_positive(atomic_t *p)
{
int v, v1;
for (v = 0; v <= 0; v = v1) {
v1 = atomic_cmpxchg(p, v, v - 1);
if (likely(v1 == v))
return 1;
}
return 0;
}
#endif
/*
* atomic_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic_t
*
* The function returns the old value of *v minus 1, even if
* the atomic variable, v, was not decremented.
*/
#ifndef atomic_dec_if_positive
static inline int atomic_dec_if_positive(atomic_t *v)
{
int c, old, dec;
c = atomic_read(v);
for (;;) {
dec = c - 1;
if (unlikely(dec < 0))
break;
old = atomic_cmpxchg((v), c, dec);
if (likely(old == c))
break;
c = old;
}
return dec;
}
#endif
/**
* atomic_fetch_or - perform *p |= mask and return old value of *p
* @mask: mask to OR on the atomic_t
* @p: pointer to atomic_t
*/
#ifndef atomic_fetch_or
static inline int atomic_fetch_or(int mask, atomic_t *p)
{
int old, val = atomic_read(p);
for (;;) {
old = atomic_cmpxchg(p, val, val | mask);
if (old == val)
break;
val = old;
}
return old;
}
#endif
#ifdef CONFIG_GENERIC_ATOMIC64
#include <asm-generic/atomic64.h>
#endif
#ifndef atomic64_andnot
static inline void atomic64_andnot(long long i, atomic64_t *v)
{
atomic64_and(~i, v);
}
static inline long long atomic64_fetch_andnot(long long i, atomic64_t *v)
{
return atomic64_fetch_and(~i, v);
}
static inline long long atomic64_fetch_andnot_relaxed(long long i, atomic64_t *v)
{
return atomic64_fetch_and_relaxed(~i, v);
}
static inline long long atomic64_fetch_andnot_acquire(long long i, atomic64_t *v)
{
return atomic64_fetch_and_acquire(~i, v);
}
static inline long long atomic64_fetch_andnot_release(long long i, atomic64_t *v)
{
return atomic64_fetch_and_release(~i, v);
}
#endif
#include <asm-generic/atomic-long.h>

21
include/linux/compiler.h
View File

@ -304,23 +304,6 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
__u.__val; \
})
/**
* smp_cond_acquire() - Spin wait for cond with ACQUIRE ordering
* @cond: boolean expression to wait for
*
* Equivalent to using smp_load_acquire() on the condition variable but employs
* the control dependency of the wait to reduce the barrier on many platforms.
*
* The control dependency provides a LOAD->STORE order, the additional RMB
* provides LOAD->LOAD order, together they provide LOAD->{LOAD,STORE} order,
* aka. ACQUIRE.
*/
#define smp_cond_acquire(cond) do { \
while (!(cond)) \
cpu_relax(); \
smp_rmb(); /* ctrl + rmb := acquire */ \
} while (0)
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
@ -545,10 +528,14 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
* Similar to rcu_dereference(), but for situations where the pointed-to
* object's lifetime is managed by something other than RCU. That
* "something other" might be reference counting or simple immortality.
*
* The seemingly unused void * variable is to validate @p is indeed a pointer
* type. All pointer types silently cast to void *.
*/
#define lockless_dereference(p) \
({ \
typeof(p) _________p1 = READ_ONCE(p); \
__maybe_unused const void * const _________p2 = _________p1; \
smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
(_________p1); \
})

12
include/linux/percpu-refcount.h
View File

@ -136,14 +136,12 @@ static inline bool __ref_is_percpu(struct percpu_ref *ref,
* used as a pointer. If the compiler generates a separate fetch
* when using it as a pointer, __PERCPU_REF_ATOMIC may be set in
* between contaminating the pointer value, meaning that
* ACCESS_ONCE() is required when fetching it.
*
* Also, we need a data dependency barrier to be paired with
* smp_store_release() in __percpu_ref_switch_to_percpu().
*
* Use lockless deref which contains both.
* READ_ONCE() is required when fetching it.
*/
percpu_ptr = lockless_dereference(ref->percpu_count_ptr);
percpu_ptr = READ_ONCE(ref->percpu_count_ptr);
/* paired with smp_store_release() in __percpu_ref_switch_to_percpu() */
smp_read_barrier_depends();
/*
* Theoretically, the following could test just ATOMIC; however,

8
include/linux/rwsem.h
View File

@ -23,10 +23,11 @@ struct rw_semaphore;
#ifdef CONFIG_RWSEM_GENERIC_SPINLOCK
#include <linux/rwsem-spinlock.h> /* use a generic implementation */
#define __RWSEM_INIT_COUNT(name) .count = RWSEM_UNLOCKED_VALUE
#else
/* All arch specific implementations share the same struct */
struct rw_semaphore {
long count;
atomic_long_t count;
struct list_head wait_list;
raw_spinlock_t wait_lock;
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
@ -54,9 +55,10 @@ extern struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem);
/* In all implementations count != 0 means locked */
static inline int rwsem_is_locked(struct rw_semaphore *sem)
{
return sem->count != 0;
return atomic_long_read(&sem->count) != 0;
}
#define __RWSEM_INIT_COUNT(name) .count = ATOMIC_LONG_INIT(RWSEM_UNLOCKED_VALUE)
#endif
/* Common initializer macros and functions */
@ -74,7 +76,7 @@ static inline int rwsem_is_locked(struct rw_semaphore *sem)
#endif
#define __RWSEM_INITIALIZER(name) \
{ .count = RWSEM_UNLOCKED_VALUE, \
{ __RWSEM_INIT_COUNT(name), \
.wait_list = LIST_HEAD_INIT((name).wait_list), \
.wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock) \
__RWSEM_OPT_INIT(name) \

10
include/linux/spinlock_up.h
View File

@ -6,6 +6,7 @@
#endif
#include <asm/processor.h> /* for cpu_relax() */
#include <asm/barrier.h>
/*
* include/linux/spinlock_up.h - UP-debug version of spinlocks.
@ -25,6 +26,11 @@
#ifdef CONFIG_DEBUG_SPINLOCK
#define arch_spin_is_locked(x) ((x)->slock == 0)
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
smp_cond_load_acquire(&lock->slock, VAL);
}
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
lock->slock = 0;
@ -67,6 +73,7 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock)
#else /* DEBUG_SPINLOCK */
#define arch_spin_is_locked(lock) ((void)(lock), 0)
#define arch_spin_unlock_wait(lock) do { barrier(); (void)(lock); } while (0)
/* for sched/core.c and kernel_lock.c: */
# define arch_spin_lock(lock) do { barrier(); (void)(lock); } while (0)
# define arch_spin_lock_flags(lock, flags) do { barrier(); (void)(lock); } while (0)
@ -79,7 +86,4 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock)
#define arch_read_can_lock(lock) (((void)(lock), 1))
#define arch_write_can_lock(lock) (((void)(lock), 1))
#define arch_spin_unlock_wait(lock) \
do { cpu_relax(); } while (arch_spin_is_locked(lock))
#endif /* __LINUX_SPINLOCK_UP_H */

13
ipc/sem.c
View File

@ -259,16 +259,6 @@ static void sem_rcu_free(struct rcu_head *head)
ipc_rcu_free(head);
}
/*
* spin_unlock_wait() and !spin_is_locked() are not memory barriers, they
* are only control barriers.
* The code must pair with spin_unlock(&sem->lock) or
* spin_unlock(&sem_perm.lock), thus just the control barrier is insufficient.
*
* smp_rmb() is sufficient, as writes cannot pass the control barrier.
*/
#define ipc_smp_acquire__after_spin_is_unlocked() smp_rmb()
/*
* Wait until all currently ongoing simple ops have completed.
* Caller must own sem_perm.lock.
@ -292,7 +282,6 @@ static void sem_wait_array(struct sem_array *sma)
sem = sma->sem_base + i;
spin_unlock_wait(&sem->lock);
}
ipc_smp_acquire__after_spin_is_unlocked();
}
/*
@ -350,7 +339,7 @@ static inline int sem_lock(struct sem_array *sma, struct sembuf *sops,
* complex_count++;
* spin_unlock(sem_perm.lock);
*/
ipc_smp_acquire__after_spin_is_unlocked();
smp_acquire__after_ctrl_dep();
/*
* Now repeat the test of complex_count:

8
kernel/exit.c
View File

@ -700,10 +700,14 @@ void do_exit(long code)
exit_signals(tsk); /* sets PF_EXITING */
/*
* tsk->flags are checked in the futex code to protect against
* an exiting task cleaning up the robust pi futexes.
* Ensure that all new tsk->pi_lock acquisitions must observe
* PF_EXITING. Serializes against futex.c:attach_to_pi_owner().
*/
smp_mb();
/*
* Ensure that we must observe the pi_state in exit_mm() ->
* mm_release() -> exit_pi_state_list().
*/
raw_spin_unlock_wait(&tsk->pi_lock);
if (unlikely(in_atomic())) {

2
kernel/jump_label.c
View File

@ -452,7 +452,7 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val,
return notifier_from_errno(ret);
}
struct notifier_block jump_label_module_nb = {
static struct notifier_block jump_label_module_nb = {
.notifier_call = jump_label_module_notify,
.priority = 1, /* higher than tracepoints */
};

13
kernel/locking/lockdep.c
View File

@ -46,6 +46,7 @@
#include <linux/gfp.h>
#include <linux/kmemcheck.h>
#include <linux/random.h>
#include <linux/jhash.h>
#include <asm/sections.h>
@ -309,10 +310,14 @@ static struct hlist_head chainhash_table[CHAINHASH_SIZE];
* It's a 64-bit hash, because it's important for the keys to be
* unique.
*/
#define iterate_chain_key(key1, key2) \
(((key1) << MAX_LOCKDEP_KEYS_BITS) ^ \
((key1) >> (64-MAX_LOCKDEP_KEYS_BITS)) ^ \
(key2))
static inline u64 iterate_chain_key(u64 key, u32 idx)
{
u32 k0 = key, k1 = key >> 32;
__jhash_mix(idx, k0, k1); /* Macro that modifies arguments! */
return k0 | (u64)k1 << 32;
}
void lockdep_off(void)
{

4
kernel/locking/mutex-debug.h
View File

@ -29,12 +29,12 @@ extern void debug_mutex_init(struct mutex *lock, const char *name,
static inline void mutex_set_owner(struct mutex *lock)
{
lock->owner = current;
WRITE_ONCE(lock->owner, current);
}
static inline void mutex_clear_owner(struct mutex *lock)
{
lock->owner = NULL;
WRITE_ONCE(lock->owner, NULL);
}
#define spin_lock_mutex(lock, flags) \

10
kernel/locking/mutex.h
View File

@ -17,14 +17,20 @@
__list_del((waiter)->list.prev, (waiter)->list.next)
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
/*
* The mutex owner can get read and written to locklessly.
* We should use WRITE_ONCE when writing the owner value to
* avoid store tearing, otherwise, a thread could potentially
* read a partially written and incomplete owner value.
*/
static inline void mutex_set_owner(struct mutex *lock)
{
lock->owner = current;
WRITE_ONCE(lock->owner, current);
}
static inline void mutex_clear_owner(struct mutex *lock)
{
lock->owner = NULL;
WRITE_ONCE(lock->owner, NULL);
}
#else
static inline void mutex_set_owner(struct mutex *lock)

2
kernel/locking/qrwlock.c
View File

@ -93,7 +93,7 @@ void queued_read_lock_slowpath(struct qrwlock *lock, u32 cnts)
* that accesses can't leak upwards out of our subsequent critical
* section in the case that the lock is currently held for write.
*/
cnts = atomic_add_return_acquire(_QR_BIAS, &lock->cnts) - _QR_BIAS;
cnts = atomic_fetch_add_acquire(_QR_BIAS, &lock->cnts);
rspin_until_writer_unlock(lock, cnts);
/*

88
kernel/locking/qspinlock.c
View File

@ -90,7 +90,7 @@ static DEFINE_PER_CPU_ALIGNED(struct mcs_spinlock, mcs_nodes[MAX_NODES]);
* therefore increment the cpu number by one.
*/
static inline u32 encode_tail(int cpu, int idx)
static inline __pure u32 encode_tail(int cpu, int idx)
{
u32 tail;
@ -103,7 +103,7 @@ static inline u32 encode_tail(int cpu, int idx)
return tail;
}
static inline struct mcs_spinlock *decode_tail(u32 tail)
static inline __pure struct mcs_spinlock *decode_tail(u32 tail)
{
int cpu = (tail >> _Q_TAIL_CPU_OFFSET) - 1;
int idx = (tail & _Q_TAIL_IDX_MASK) >> _Q_TAIL_IDX_OFFSET;
@ -267,6 +267,63 @@ static __always_inline u32 __pv_wait_head_or_lock(struct qspinlock *lock,
#define queued_spin_lock_slowpath native_queued_spin_lock_slowpath
#endif
/*
* Various notes on spin_is_locked() and spin_unlock_wait(), which are
* 'interesting' functions:
*
* PROBLEM: some architectures have an interesting issue with atomic ACQUIRE
* operations in that the ACQUIRE applies to the LOAD _not_ the STORE (ARM64,
* PPC). Also qspinlock has a similar issue per construction, the setting of
* the locked byte can be unordered acquiring the lock proper.
*
* This gets to be 'interesting' in the following cases, where the /should/s
* end up false because of this issue.
*
*
* CASE 1:
*
* So the spin_is_locked() correctness issue comes from something like:
*
* CPU0 CPU1
*
* global_lock(); local_lock(i)
* spin_lock(&G) spin_lock(&L[i])
* for (i) if (!spin_is_locked(&G)) {
* spin_unlock_wait(&L[i]); smp_acquire__after_ctrl_dep();
* return;
* }
* // deal with fail
*
* Where it is important CPU1 sees G locked or CPU0 sees L[i] locked such
* that there is exclusion between the two critical sections.
*
* The load from spin_is_locked(&G) /should/ be constrained by the ACQUIRE from
* spin_lock(&L[i]), and similarly the load(s) from spin_unlock_wait(&L[i])
* /should/ be constrained by the ACQUIRE from spin_lock(&G).
*
* Similarly, later stuff is constrained by the ACQUIRE from CTRL+RMB.
*
*
* CASE 2:
*
* For spin_unlock_wait() there is a second correctness issue, namely:
*
* CPU0 CPU1
*
* flag = set;
* smp_mb(); spin_lock(&l)
* spin_unlock_wait(&l); if (!flag)
* // add to lockless list
* spin_unlock(&l);
* // iterate lockless list
*
* Which wants to ensure that CPU1 will stop adding bits to the list and CPU0
* will observe the last entry on the list (if spin_unlock_wait() had ACQUIRE
* semantics etc..)
*
* Where flag /should/ be ordered against the locked store of l.
*/
/*
* queued_spin_lock_slowpath() can (load-)ACQUIRE the lock before
* issuing an _unordered_ store to set _Q_LOCKED_VAL.
@ -322,7 +379,7 @@ void queued_spin_unlock_wait(struct qspinlock *lock)
cpu_relax();
done:
smp_rmb(); /* CTRL + RMB -> ACQUIRE */
smp_acquire__after_ctrl_dep();
}
EXPORT_SYMBOL(queued_spin_unlock_wait);
#endif
@ -418,7 +475,7 @@ void queued_spin_lock_slowpath(struct qspinlock *lock, u32 val)
* sequentiality; this is because not all clear_pending_set_locked()
* implementations imply full barriers.
*/
smp_cond_acquire(!(atomic_read(&lock->val) & _Q_LOCKED_MASK));
smp_cond_load_acquire(&lock->val.counter, !(VAL & _Q_LOCKED_MASK));
/*
* take ownership and clear the pending bit.
@ -455,6 +512,8 @@ queue:
* pending stuff.
*
* p,*,* -> n,*,*
*
* RELEASE, such that the stores to @node must be complete.
*/
old = xchg_tail(lock, tail);
next = NULL;
@ -465,6 +524,15 @@ queue:
*/
if (old & _Q_TAIL_MASK) {
prev = decode_tail(old);
/*
* The above xchg_tail() is also a load of @lock which generates,
* through decode_tail(), a pointer.
*
* The address dependency matches the RELEASE of xchg_tail()
* such that the access to @prev must happen after.
*/
smp_read_barrier_depends();
WRITE_ONCE(prev->next, node);
pv_wait_node(node, prev);
@ -494,7 +562,7 @@ queue:
*
* The PV pv_wait_head_or_lock function, if active, will acquire
* the lock and return a non-zero value. So we have to skip the
* smp_cond_acquire() call. As the next PV queue head hasn't been
* smp_cond_load_acquire() call. As the next PV queue head hasn't been
* designated yet, there is no way for the locked value to become
* _Q_SLOW_VAL. So both the set_locked() and the
* atomic_cmpxchg_relaxed() calls will be safe.
@ -505,7 +573,7 @@ queue:
if ((val = pv_wait_head_or_lock(lock, node)))
goto locked;
smp_cond_acquire(!((val = atomic_read(&lock->val)) & _Q_LOCKED_PENDING_MASK));
val = smp_cond_load_acquire(&lock->val.counter, !(VAL & _Q_LOCKED_PENDING_MASK));
locked:
/*
@ -525,9 +593,9 @@ locked:
break;
}
/*
* The smp_cond_acquire() call above has provided the necessary
* acquire semantics required for locking. At most two
* iterations of this loop may be ran.
* The smp_cond_load_acquire() call above has provided the
* necessary acquire semantics required for locking. At most
* two iterations of this loop may be ran.
*/
old = atomic_cmpxchg_relaxed(&lock->val, val, _Q_LOCKED_VAL);
if (old == val)
@ -551,7 +619,7 @@ release:
/*
* release the node
*/
this_cpu_dec(mcs_nodes[0].count);
__this_cpu_dec(mcs_nodes[0].count);
}
EXPORT_SYMBOL(queued_spin_lock_slowpath);

4
kernel/locking/qspinlock_paravirt.h
View File

@ -112,12 +112,12 @@ static __always_inline int trylock_clear_pending(struct qspinlock *lock)
#else /* _Q_PENDING_BITS == 8 */
static __always_inline void set_pending(struct qspinlock *lock)
{
atomic_set_mask(_Q_PENDING_VAL, &lock->val);
atomic_or(_Q_PENDING_VAL, &lock->val);
}
static __always_inline void clear_pending(struct qspinlock *lock)
{
atomic_clear_mask(_Q_PENDING_VAL, &lock->val);
atomic_andnot(_Q_PENDING_VAL, &lock->val);
}
static __always_inline int trylock_clear_pending(struct qspinlock *lock)

2
kernel/locking/rtmutex.c
View File

@ -1478,7 +1478,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_timed_lock);
*/
int __sched rt_mutex_trylock(struct rt_mutex *lock)
{
if (WARN_ON(in_irq() || in_nmi() || in_serving_softirq()))
if (WARN_ON_ONCE(in_irq() || in_nmi() || in_serving_softirq()))
return 0;
return rt_mutex_fasttrylock(lock, rt_mutex_slowtrylock);

194
kernel/locking/rwsem-xadd.c
View File

@ -80,7 +80,7 @@ void __init_rwsem(struct rw_semaphore *sem, const char *name,
debug_check_no_locks_freed((void *)sem, sizeof(*sem));
lockdep_init_map(&sem->dep_map, name, key, 0);
#endif
sem->count = RWSEM_UNLOCKED_VALUE;
atomic_long_set(&sem->count, RWSEM_UNLOCKED_VALUE);
raw_spin_lock_init(&sem->wait_lock);
INIT_LIST_HEAD(&sem->wait_list);
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
@ -114,12 +114,16 @@ enum rwsem_wake_type {
* - the 'active part' of count (&0x0000ffff) reached 0 (but may have changed)
* - the 'waiting part' of count (&0xffff0000) is -ve (and will still be so)
* - there must be someone on the queue
* - the spinlock must be held by the caller
* - the wait_lock must be held by the caller
* - tasks are marked for wakeup, the caller must later invoke wake_up_q()
* to actually wakeup the blocked task(s) and drop the reference count,
* preferably when the wait_lock is released
* - woken process blocks are discarded from the list after having task zeroed
* - writers are only woken if downgrading is false
* - writers are only marked woken if downgrading is false
*/
static struct rw_semaphore *
__rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
__rwsem_mark_wake(struct rw_semaphore *sem,
enum rwsem_wake_type wake_type, struct wake_q_head *wake_q)
{
struct rwsem_waiter *waiter;
struct task_struct *tsk;
@ -128,13 +132,16 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
if (waiter->type == RWSEM_WAITING_FOR_WRITE) {
if (wake_type == RWSEM_WAKE_ANY)
/* Wake writer at the front of the queue, but do not
* grant it the lock yet as we want other writers
* to be able to steal it. Readers, on the other hand,
* will block as they will notice the queued writer.
if (wake_type == RWSEM_WAKE_ANY) {
/*
* Mark writer at the front of the queue for wakeup.
* Until the task is actually later awoken later by
* the caller, other writers are able to steal it.
* Readers, on the other hand, will block as they
* will notice the queued writer.
*/
wake_up_process(waiter->task);
wake_q_add(wake_q, waiter->task);
}
goto out;
}
@ -146,15 +153,27 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
if (wake_type != RWSEM_WAKE_READ_OWNED) {
adjustment = RWSEM_ACTIVE_READ_BIAS;
try_reader_grant:
oldcount = rwsem_atomic_update(adjustment, sem) - adjustment;
oldcount = atomic_long_fetch_add(adjustment, &sem->count);
if (unlikely(oldcount < RWSEM_WAITING_BIAS)) {
/* A writer stole the lock. Undo our reader grant. */
if (rwsem_atomic_update(-adjustment, sem) &
RWSEM_ACTIVE_MASK)
/*
* If the count is still less than RWSEM_WAITING_BIAS
* after removing the adjustment, it is assumed that
* a writer has stolen the lock. We have to undo our
* reader grant.
*/
if (atomic_long_add_return(-adjustment, &sem->count) <
RWSEM_WAITING_BIAS)
goto out;
/* Last active locker left. Retry waking readers. */
goto try_reader_grant;
}
/*
* It is not really necessary to set it to reader-owned here,
* but it gives the spinners an early indication that the
* readers now have the lock.
*/
rwsem_set_reader_owned(sem);
}
/* Grant an infinite number of read locks to the readers at the front
@ -179,7 +198,7 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
adjustment -= RWSEM_WAITING_BIAS;
if (adjustment)
rwsem_atomic_add(adjustment, sem);
atomic_long_add(adjustment, &sem->count);
next = sem->wait_list.next;
loop = woken;
@ -187,17 +206,15 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
waiter = list_entry(next, struct rwsem_waiter, list);
next = waiter->list.next;
tsk = waiter->task;
wake_q_add(wake_q, tsk);
/*
* Make sure we do not wakeup the next reader before
* setting the nil condition to grant the next reader;
* otherwise we could miss the wakeup on the other
* side and end up sleeping again. See the pairing
* in rwsem_down_read_failed().
* Ensure that the last operation is setting the reader
* waiter to nil such that rwsem_down_read_failed() cannot
* race with do_exit() by always holding a reference count
* to the task to wakeup.
*/
smp_mb();
waiter->task = NULL;
wake_up_process(tsk);
put_task_struct(tsk);
smp_store_release(&waiter->task, NULL);
} while (--loop);
sem->wait_list.next = next;
@ -216,11 +233,11 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
long count, adjustment = -RWSEM_ACTIVE_READ_BIAS;
struct rwsem_waiter waiter;
struct task_struct *tsk = current;
WAKE_Q(wake_q);
/* set up my own style of waitqueue */
waiter.task = tsk;
waiter.type = RWSEM_WAITING_FOR_READ;
get_task_struct(tsk);
raw_spin_lock_irq(&sem->wait_lock);
if (list_empty(&sem->wait_list))
@ -228,7 +245,7 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
list_add_tail(&waiter.list, &sem->wait_list);
/* we're now waiting on the lock, but no longer actively locking */
count = rwsem_atomic_update(adjustment, sem);
count = atomic_long_add_return(adjustment, &sem->count);
/* If there are no active locks, wake the front queued process(es).
*
@ -238,9 +255,10 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
if (count == RWSEM_WAITING_BIAS ||
(count > RWSEM_WAITING_BIAS &&
adjustment != -RWSEM_ACTIVE_READ_BIAS))
sem = __rwsem_do_wake(sem, RWSEM_WAKE_ANY);
sem = __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
raw_spin_unlock_irq(&sem->wait_lock);
wake_up_q(&wake_q);
/* wait to be given the lock */
while (true) {
@ -255,17 +273,29 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
}
EXPORT_SYMBOL(rwsem_down_read_failed);
/*
* This function must be called with the sem->wait_lock held to prevent
* race conditions between checking the rwsem wait list and setting the
* sem->count accordingly.
*/
static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem)
{
/*
* Try acquiring the write lock. Check count first in order
* to reduce unnecessary expensive cmpxchg() operations.
* Avoid trying to acquire write lock if count isn't RWSEM_WAITING_BIAS.
*/
if (count == RWSEM_WAITING_BIAS &&
cmpxchg_acquire(&sem->count, RWSEM_WAITING_BIAS,
RWSEM_ACTIVE_WRITE_BIAS) == RWSEM_WAITING_BIAS) {
if (!list_is_singular(&sem->wait_list))
rwsem_atomic_update(RWSEM_WAITING_BIAS, sem);
if (count != RWSEM_WAITING_BIAS)
return false;
/*
* Acquire the lock by trying to set it to ACTIVE_WRITE_BIAS. If there
* are other tasks on the wait list, we need to add on WAITING_BIAS.
*/
count = list_is_singular(&sem->wait_list) ?
RWSEM_ACTIVE_WRITE_BIAS :
RWSEM_ACTIVE_WRITE_BIAS + RWSEM_WAITING_BIAS;
if (atomic_long_cmpxchg_acquire(&sem->count, RWSEM_WAITING_BIAS, count)
== RWSEM_WAITING_BIAS) {
rwsem_set_owner(sem);
return true;
}
@ -279,13 +309,13 @@ static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem)
*/
static inline bool rwsem_try_write_lock_unqueued(struct rw_semaphore *sem)
{
long old, count = READ_ONCE(sem->count);
long old, count = atomic_long_read(&sem->count);
while (true) {
if (!(count == 0 || count == RWSEM_WAITING_BIAS))
return false;
old = cmpxchg_acquire(&sem->count, count,
old = atomic_long_cmpxchg_acquire(&sem->count, count,
count + RWSEM_ACTIVE_WRITE_BIAS);
if (old == count) {
rwsem_set_owner(sem);
@ -306,16 +336,11 @@ static inline bool rwsem_can_spin_on_owner(struct rw_semaphore *sem)
rcu_read_lock();
owner = READ_ONCE(sem->owner);
if (!owner) {
long count = READ_ONCE(sem->count);
if (!rwsem_owner_is_writer(owner)) {
/*
* If sem->owner is not set, yet we have just recently entered the
* slowpath with the lock being active, then there is a possibility
* reader(s) may have the lock. To be safe, bail spinning in these
* situations.
* Don't spin if the rwsem is readers owned.
*/
if (count & RWSEM_ACTIVE_MASK)
ret = false;
ret = !rwsem_owner_is_reader(owner);
goto done;
}
@ -325,10 +350,15 @@ done:
return ret;
}
static noinline
bool rwsem_spin_on_owner(struct rw_semaphore *sem, struct task_struct *owner)
/*
* Return true only if we can still spin on the owner field of the rwsem.
*/
static noinline bool rwsem_spin_on_owner(struct rw_semaphore *sem)
{
long count;
struct task_struct *owner = READ_ONCE(sem->owner);
if (!rwsem_owner_is_writer(owner))
goto out;
rcu_read_lock();
while (sem->owner == owner) {
@ -349,22 +379,16 @@ bool rwsem_spin_on_owner(struct rw_semaphore *sem, struct task_struct *owner)
cpu_relax_lowlatency();
}
rcu_read_unlock();
if (READ_ONCE(sem->owner))
return true; /* new owner, continue spinning */
out:
/*
* When the owner is not set, the lock could be free or
* held by readers. Check the counter to verify the
* state.
* If there is a new owner or the owner is not set, we continue
* spinning.
*/
count = READ_ONCE(sem->count);
return (count == 0 || count == RWSEM_WAITING_BIAS);
return !rwsem_owner_is_reader(READ_ONCE(sem->owner));
}
static bool rwsem_optimistic_spin(struct rw_semaphore *sem)
{
struct task_struct *owner;
bool taken = false;
preempt_disable();
@ -376,12 +400,17 @@ static bool rwsem_optimistic_spin(struct rw_semaphore *sem)
if (!osq_lock(&sem->osq))
goto done;
while (true) {
owner = READ_ONCE(sem->owner);
if (owner && !rwsem_spin_on_owner(sem, owner))
break;
/* wait_lock will be acquired if write_lock is obtained */
/*
* Optimistically spin on the owner field and attempt to acquire the
* lock whenever the owner changes. Spinning will be stopped when:
* 1) the owning writer isn't running; or
* 2) readers own the lock as we can't determine if they are
* actively running or not.
*/
while (rwsem_spin_on_owner(sem)) {
/*
* Try to acquire the lock
*/
if (rwsem_try_write_lock_unqueued(sem)) {
taken = true;
break;
@ -393,7 +422,7 @@ static bool rwsem_optimistic_spin(struct rw_semaphore *sem)
* we're an RT task that will live-lock because we won't let
* the owner complete.
*/
if (!owner && (need_resched() || rt_task(current)))
if (!sem->owner && (need_resched() || rt_task(current)))
break;
/*
@ -440,9 +469,10 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state)
bool waiting = true; /* any queued threads before us */
struct rwsem_waiter waiter;
struct rw_semaphore *ret = sem;
WAKE_Q(wake_q);
/* undo write bias from down_write operation, stop active locking */
count = rwsem_atomic_update(-RWSEM_ACTIVE_WRITE_BIAS, sem);
count = atomic_long_sub_return(RWSEM_ACTIVE_WRITE_BIAS, &sem->count);
/* do optimistic spinning and steal lock if possible */
if (rwsem_optimistic_spin(sem))
@ -465,18 +495,29 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state)
/* we're now waiting on the lock, but no longer actively locking */
if (waiting) {
count = READ_ONCE(sem->count);
count = atomic_long_read(&sem->count);
/*
* If there were already threads queued before us and there are
* no active writers, the lock must be read owned; so we try to
* wake any read locks that were queued ahead of us.
*/
if (count > RWSEM_WAITING_BIAS)
sem = __rwsem_do_wake(sem, RWSEM_WAKE_READERS);
if (count > RWSEM_WAITING_BIAS) {
WAKE_Q(wake_q);
sem = __rwsem_mark_wake(sem, RWSEM_WAKE_READERS, &wake_q);
/*
* The wakeup is normally called _after_ the wait_lock
* is released, but given that we are proactively waking
* readers we can deal with the wake_q overhead as it is
* similar to releasing and taking the wait_lock again
* for attempting rwsem_try_write_lock().
*/
wake_up_q(&wake_q);
}
} else
count = rwsem_atomic_update(RWSEM_WAITING_BIAS, sem);
count = atomic_long_add_return(RWSEM_WAITING_BIAS, &sem->count);
/* wait until we successfully acquire the lock */
set_current_state(state);
@ -492,7 +533,7 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state)
schedule();
set_current_state(state);
} while ((count = sem->count) & RWSEM_ACTIVE_MASK);
} while ((count = atomic_long_read(&sem->count)) & RWSEM_ACTIVE_MASK);
raw_spin_lock_irq(&sem->wait_lock);
}
@ -507,10 +548,11 @@ out_nolock:
raw_spin_lock_irq(&sem->wait_lock);
list_del(&waiter.list);
if (list_empty(&sem->wait_list))
rwsem_atomic_update(-RWSEM_WAITING_BIAS, sem);
atomic_long_add(-RWSEM_WAITING_BIAS, &sem->count);
else
__rwsem_do_wake(sem, RWSEM_WAKE_ANY);
__rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
raw_spin_unlock_irq(&sem->wait_lock);
wake_up_q(&wake_q);
return ERR_PTR(-EINTR);
}
@ -537,6 +579,7 @@ __visible
struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
{
unsigned long flags;
WAKE_Q(wake_q);
/*
* If a spinner is present, it is not necessary to do the wakeup.
@ -573,9 +616,10 @@ locked:
/* do nothing if list empty */
if (!list_empty(&sem->wait_list))
sem = __rwsem_do_wake(sem, RWSEM_WAKE_ANY);
sem = __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
wake_up_q(&wake_q);
return sem;
}
@ -590,14 +634,16 @@ __visible
struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
{
unsigned long flags;
WAKE_Q(wake_q);
raw_spin_lock_irqsave(&sem->wait_lock, flags);
/* do nothing if list empty */
if (!list_empty(&sem->wait_list))
sem = __rwsem_do_wake(sem, RWSEM_WAKE_READ_OWNED);
sem = __rwsem_mark_wake(sem, RWSEM_WAKE_READ_OWNED, &wake_q);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
wake_up_q(&wake_q);
return sem;
}

8
kernel/locking/rwsem.c
View File

@ -22,6 +22,7 @@ void __sched down_read(struct rw_semaphore *sem)
rwsem_acquire_read(&sem->dep_map, 0, 0, _RET_IP_);
LOCK_CONTENDED(sem, __down_read_trylock, __down_read);
rwsem_set_reader_owned(sem);
}
EXPORT_SYMBOL(down_read);
@ -33,8 +34,10 @@ int down_read_trylock(struct rw_semaphore *sem)
{
int ret = __down_read_trylock(sem);
if (ret == 1)
if (ret == 1) {
rwsem_acquire_read(&sem->dep_map, 0, 1, _RET_IP_);
rwsem_set_reader_owned(sem);
}
return ret;
}
@ -124,7 +127,7 @@ void downgrade_write(struct rw_semaphore *sem)
* lockdep: a downgraded write will live on as a write
* dependency.
*/
rwsem_clear_owner(sem);
rwsem_set_reader_owned(sem);
__downgrade_write(sem);
}
@ -138,6 +141,7 @@ void down_read_nested(struct rw_semaphore *sem, int subclass)
rwsem_acquire_read(&sem->dep_map, subclass, 0, _RET_IP_);
LOCK_CONTENDED(sem, __down_read_trylock, __down_read);
rwsem_set_reader_owned(sem);
}
EXPORT_SYMBOL(down_read_nested);

52
kernel/locking/rwsem.h
View File

@ -1,14 +1,58 @@
/*
* The owner field of the rw_semaphore structure will be set to
* RWSEM_READ_OWNED when a reader grabs the lock. A writer will clear
* the owner field when it unlocks. A reader, on the other hand, will
* not touch the owner field when it unlocks.
*
* In essence, the owner field now has the following 3 states:
* 1) 0
* - lock is free or the owner hasn't set the field yet
* 2) RWSEM_READER_OWNED
* - lock is currently or previously owned by readers (lock is free
* or not set by owner yet)
* 3) Other non-zero value
* - a writer owns the lock
*/
#define RWSEM_READER_OWNED ((struct task_struct *)1UL)
#ifdef CONFIG_RWSEM_SPIN_ON_OWNER
/*
* All writes to owner are protected by WRITE_ONCE() to make sure that
* store tearing can't happen as optimistic spinners may read and use
* the owner value concurrently without lock. Read from owner, however,
* may not need READ_ONCE() as long as the pointer value is only used
* for comparison and isn't being dereferenced.
*/
static inline void rwsem_set_owner(struct rw_semaphore *sem)
{
sem->owner = current;
WRITE_ONCE(sem->owner, current);
}
static inline void rwsem_clear_owner(struct rw_semaphore *sem)
{
sem->owner = NULL;
WRITE_ONCE(sem->owner, NULL);
}
static inline void rwsem_set_reader_owned(struct rw_semaphore *sem)
{
/*
* We check the owner value first to make sure that we will only
* do a write to the rwsem cacheline when it is really necessary
* to minimize cacheline contention.
*/
if (sem->owner != RWSEM_READER_OWNED)
WRITE_ONCE(sem->owner, RWSEM_READER_OWNED);
}
static inline bool rwsem_owner_is_writer(struct task_struct *owner)
{
return owner && owner != RWSEM_READER_OWNED;
}
static inline bool rwsem_owner_is_reader(struct task_struct *owner)
{
return owner == RWSEM_READER_OWNED;
}
#else
static inline void rwsem_set_owner(struct rw_semaphore *sem)
{
@ -17,4 +61,8 @@ static inline void rwsem_set_owner(struct rw_semaphore *sem)
static inline void rwsem_clear_owner(struct rw_semaphore *sem)
{
}
static inline void rwsem_set_reader_owned(struct rw_semaphore *sem)
{
}
#endif

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