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| author | Mark Rutland <mark.rutland@arm.com> | 2018-06-21 13:13:11 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-06-21 14:25:21 +0200 |
| commit | 00b808ab79ead372daf1a0682d1ef271599c0b55 (patch) | |
| tree | b6b2384e169533b9f40e213f7cb49cab190c23f5 | |
| parent | 0ae1d994020d75ac065fd42ac4cbf5ac6ce9b255 (diff) | |
| download | linux-rpi-00b808ab79ead372daf1a0682d1ef271599c0b55.tar.gz linux-rpi-00b808ab79ead372daf1a0682d1ef271599c0b55.tar.bz2 linux-rpi-00b808ab79ead372daf1a0682d1ef271599c0b55.zip | |
atomics/generic: Define atomic64_fetch_add_unless()
As a step towards unifying the atomic/atomic64/atomic_long APIs, this
patch converts the generic implementation of atomic64_add_unless() into
a generic implementation of atomic64_fetch_add_unless().
A wrapper in <linux/atomic.h> will build atomic_add_unless() atop of
this, provided it is given a preprocessor definition.
No functional change is intended 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: Arnd Bergmann <arnd@arndb.de>
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/20180621121321.4761-9-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | include/asm-generic/atomic64.h | 3 | ||||
| -rw-r--r-- | lib/atomic64.c | 14 |
2 files changed, 9 insertions, 8 deletions
diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h index 5105275ac825..49460107b29a 100644 --- a/include/asm-generic/atomic64.h +++ b/include/asm-generic/atomic64.h @@ -53,7 +53,8 @@ ATOMIC64_OPS(xor) extern long long atomic64_dec_if_positive(atomic64_t *v); extern long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n); extern long long atomic64_xchg(atomic64_t *v, long long new); -extern bool atomic64_add_unless(atomic64_t *v, long long a, long long u); +extern long long atomic64_fetch_add_unless(atomic64_t *v, long long a, long long u); +#define atomic64_fetch_add_unless atomic64_fetch_add_unless #define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0) #define atomic64_inc(v) atomic64_add(1LL, (v)) diff --git a/lib/atomic64.c b/lib/atomic64.c index 4230f4b8906c..1d91e31eceec 100644 --- a/lib/atomic64.c +++ b/lib/atomic64.c @@ -178,18 +178,18 @@ long long atomic64_xchg(atomic64_t *v, long long new) } EXPORT_SYMBOL(atomic64_xchg); -bool atomic64_add_unless(atomic64_t *v, long long a, long long u) +long long atomic64_fetch_add_unless(atomic64_t *v, long long a, long long u) { unsigned long flags; raw_spinlock_t *lock = lock_addr(v); - bool ret = false; + long long val; raw_spin_lock_irqsave(lock, flags); - if (v->counter != u) { + val = v->counter; + if (val != u) v->counter += a; - ret = true; - } raw_spin_unlock_irqrestore(lock, flags); - return ret; + + return val; } -EXPORT_SYMBOL(atomic64_add_unless); +EXPORT_SYMBOL(atomic64_fetch_add_unless); |