linux/arch/arm64/include/asm/atomic.h
Peter Zijlstra e490f9b1d3 locking/atomic, arch/arm64: Implement atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.

This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).

[wildea01: compile fixes for ll/sc]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-16 10:48:21 +02:00

213 lines
8.4 KiB
C

/*
* Based on arch/arm/include/asm/atomic.h
*
* Copyright (C) 1996 Russell King.
* Copyright (C) 2002 Deep Blue Solutions Ltd.
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_ATOMIC_H
#define __ASM_ATOMIC_H
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/lse.h>
#ifdef __KERNEL__
#define __ARM64_IN_ATOMIC_IMPL
#if defined(CONFIG_ARM64_LSE_ATOMICS) && defined(CONFIG_AS_LSE)
#include <asm/atomic_lse.h>
#else
#include <asm/atomic_ll_sc.h>
#endif
#undef __ARM64_IN_ATOMIC_IMPL
#include <asm/cmpxchg.h>
#define ___atomic_add_unless(v, a, u, sfx) \
({ \
typeof((v)->counter) c, old; \
\
c = atomic##sfx##_read(v); \
while (c != (u) && \
(old = atomic##sfx##_cmpxchg((v), c, c + (a))) != c) \
c = old; \
c; \
})
#define ATOMIC_INIT(i) { (i) }
#define atomic_read(v) READ_ONCE((v)->counter)
#define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_add_return_acquire atomic_add_return_acquire
#define atomic_add_return_release atomic_add_return_release
#define atomic_add_return atomic_add_return
#define atomic_inc_return_relaxed(v) atomic_add_return_relaxed(1, (v))
#define atomic_inc_return_acquire(v) atomic_add_return_acquire(1, (v))
#define atomic_inc_return_release(v) atomic_add_return_release(1, (v))
#define atomic_inc_return(v) atomic_add_return(1, (v))
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_sub_return_acquire atomic_sub_return_acquire
#define atomic_sub_return_release atomic_sub_return_release
#define atomic_sub_return atomic_sub_return
#define atomic_dec_return_relaxed(v) atomic_sub_return_relaxed(1, (v))
#define atomic_dec_return_acquire(v) atomic_sub_return_acquire(1, (v))
#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))
#define atomic_xchg(v, new) xchg(&((v)->counter), (new))
#define atomic_cmpxchg_relaxed(v, old, new) \
cmpxchg_relaxed(&((v)->counter), (old), (new))
#define atomic_cmpxchg_acquire(v, old, new) \
cmpxchg_acquire(&((v)->counter), (old), (new))
#define atomic_cmpxchg_release(v, old, new) \
cmpxchg_release(&((v)->counter), (old), (new))
#define atomic_cmpxchg(v, old, new) cmpxchg(&((v)->counter), (old), (new))
#define atomic_inc(v) atomic_add(1, (v))
#define atomic_dec(v) atomic_sub(1, (v))
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
#define atomic_add_negative(i, v) (atomic_add_return((i), (v)) < 0)
#define __atomic_add_unless(v, a, u) ___atomic_add_unless(v, a, u,)
#define atomic_andnot atomic_andnot
#define atomic_fetch_or atomic_fetch_or
/*
* 64-bit atomic operations.
*/
#define ATOMIC64_INIT ATOMIC_INIT
#define atomic64_read atomic_read
#define atomic64_set atomic_set
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_add_return_acquire atomic64_add_return_acquire
#define atomic64_add_return_release atomic64_add_return_release
#define atomic64_add_return atomic64_add_return
#define atomic64_inc_return_relaxed(v) atomic64_add_return_relaxed(1, (v))
#define atomic64_inc_return_acquire(v) atomic64_add_return_acquire(1, (v))
#define atomic64_inc_return_release(v) atomic64_add_return_release(1, (v))
#define atomic64_inc_return(v) atomic64_add_return(1, (v))
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_sub_return_acquire atomic64_sub_return_acquire
#define atomic64_sub_return_release atomic64_sub_return_release
#define atomic64_sub_return atomic64_sub_return
#define atomic64_dec_return_relaxed(v) atomic64_sub_return_relaxed(1, (v))
#define atomic64_dec_return_acquire(v) atomic64_sub_return_acquire(1, (v))
#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
#define atomic64_xchg atomic_xchg
#define atomic64_cmpxchg_relaxed atomic_cmpxchg_relaxed
#define atomic64_cmpxchg_acquire atomic_cmpxchg_acquire
#define atomic64_cmpxchg_release atomic_cmpxchg_release
#define atomic64_cmpxchg atomic_cmpxchg
#define atomic64_inc(v) atomic64_add(1, (v))
#define atomic64_dec(v) atomic64_sub(1, (v))
#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
#define atomic64_dec_and_test(v) (atomic64_dec_return(v) == 0)
#define atomic64_sub_and_test(i, v) (atomic64_sub_return((i), (v)) == 0)
#define atomic64_add_negative(i, v) (atomic64_add_return((i), (v)) < 0)
#define atomic64_add_unless(v, a, u) (___atomic_add_unless(v, a, u, 64) != u)
#define atomic64_andnot atomic64_andnot
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
#endif
#endif