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| author | Mark Rutland <mark.rutland@arm.com> | 2018-06-21 13:13:20 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-06-21 14:25:24 +0200 |
| commit | b3a2a05f9111de0b79312e577608a27b0318c0a1 (patch) | |
| tree | 284f54a489fe4dc810ffde4eac4aad414017202d /include/asm-generic/atomic-instrumented.h | |
| parent | 9837559d8eb01ce834e56fc9a567c1d94ebd3698 (diff) | |
| download | lwn-b3a2a05f9111de0b79312e577608a27b0318c0a1.tar.gz lwn-b3a2a05f9111de0b79312e577608a27b0318c0a1.zip | |
atomics/treewide: Make conditional inc/dec ops optional
The conditional inc/dec ops differ for atomic_t and atomic64_t:
- atomic_inc_unless_positive() is optional for atomic_t, and doesn't exist for atomic64_t.
- atomic_dec_unless_negative() is optional for atomic_t, and doesn't exist for atomic64_t.
- atomic_dec_if_positive is optional for atomic_t, and is mandatory for atomic64_t.
Let's make these consistently optional for both. At the same time, let's
clean up the existing fallbacks to use atomic_try_cmpxchg().
The instrumented atomics are updated accordingly.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-18-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/asm-generic/atomic-instrumented.h')
| -rw-r--r-- | include/asm-generic/atomic-instrumented.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/asm-generic/atomic-instrumented.h b/include/asm-generic/atomic-instrumented.h index 12f9634750d7..3c64e95d5ed0 100644 --- a/include/asm-generic/atomic-instrumented.h +++ b/include/asm-generic/atomic-instrumented.h @@ -243,11 +243,14 @@ static __always_inline bool atomic64_inc_not_zero(atomic64_t *v) } #endif +#ifdef arch_atomic64_dec_if_positive +#define atomic64_dec_if_positive atomic64_dec_if_positive static __always_inline s64 atomic64_dec_if_positive(atomic64_t *v) { kasan_check_write(v, sizeof(*v)); return arch_atomic64_dec_if_positive(v); } +#endif #ifdef arch_atomic_dec_and_test #define atomic_dec_and_test atomic_dec_and_test |