linux/include/asm-mips/futex.h
Ingo Molnar 8f17d3a504 [PATCH] lightweight robust futexes updates
- fix: initialize the robust list(s) to NULL in copy_process.

- doc update

- cleanup: rename _inuser to _inatomic

- __user cleanups and other small cleanups

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:49 -08:00

110 lines
2.5 KiB
C

#ifndef _ASM_FUTEX_H
#define _ASM_FUTEX_H
#ifdef __KERNEL__
#include <linux/config.h>
#include <linux/futex.h>
#include <asm/errno.h>
#include <asm/uaccess.h>
#ifdef CONFIG_SMP
#define __FUTEX_SMP_SYNC " sync \n"
#else
#define __FUTEX_SMP_SYNC
#endif
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
{ \
__asm__ __volatile__( \
" .set push \n" \
" .set noat \n" \
" .set mips3 \n" \
"1: ll %1, (%3) # __futex_atomic_op1 \n" \
" .set mips0 \n" \
" " insn " \n" \
" .set mips3 \n" \
"2: sc $1, (%3) \n" \
" beqzl $1, 1b \n" \
__FUTEX_SMP_SYNC \
"3: \n" \
" .set pop \n" \
" .set mips0 \n" \
" .section .fixup,\"ax\" \n" \
"4: li %0, %5 \n" \
" j 2b \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" "__UA_ADDR "\t1b, 4b \n" \
" "__UA_ADDR "\t2b, 4b \n" \
" .previous \n" \
: "=r" (ret), "=r" (oldval) \
: "0" (0), "r" (uaddr), "Jr" (oparg), "i" (-EFAULT)); \
}
static inline int
futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
{
int op = (encoded_op >> 28) & 7;
int cmp = (encoded_op >> 24) & 15;
int oparg = (encoded_op << 8) >> 20;
int cmparg = (encoded_op << 20) >> 20;
int oldval = 0, ret;
if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
oparg = 1 << oparg;
if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
return -EFAULT;
inc_preempt_count();
switch (op) {
case FUTEX_OP_SET:
__futex_atomic_op("move $1, %z4", ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ADD:
__futex_atomic_op("addu $1, %1, %z4",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_OR:
__futex_atomic_op("or $1, %1, %z4",
ret, oldval, uaddr, oparg);
break;
case FUTEX_OP_ANDN:
__futex_atomic_op("and $1, %1, %z4",
ret, oldval, uaddr, ~oparg);
break;
case FUTEX_OP_XOR:
__futex_atomic_op("xor $1, %1, %z4",
ret, oldval, uaddr, oparg);
break;
default:
ret = -ENOSYS;
}
dec_preempt_count();
if (!ret) {
switch (cmp) {
case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
default: ret = -ENOSYS;
}
}
return ret;
}
static inline int
futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
{
return -ENOSYS;
}
#endif
#endif