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.rutl...@arm.com> Cc: Boqun Feng <boqun.f...@gmail.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Will Deacon <will.dea...@arm.com> Cc: Arnd Bergmann <a...@arndb.de> --- include/asm-generic/atomic64.h | 3 ++- lib/atomic64.c | 13 ++++++------- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h index e9a94b7a4d0a..b0aa425361ad 100644 --- a/include/asm-generic/atomic64.h +++ b/include/asm-generic/atomic64.h @@ -52,7 +52,8 @@ 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 int 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 53c2d5edc826..fb2a38af5ae8 100644 --- a/lib/atomic64.c +++ b/lib/atomic64.c @@ -178,18 +178,17 @@ long long atomic64_xchg(atomic64_t *v, long long new) } EXPORT_SYMBOL(atomic64_xchg); -int 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); - int ret = 0; + long long val; raw_spin_lock_irqsave(lock, flags); - if (v->counter != u) { + val = v->counter; + if (val != u) v->counter += a; - ret = 1; - } raw_spin_unlock_irqrestore(lock, flags); - return ret; + return val; } -EXPORT_SYMBOL(atomic64_add_unless); +EXPORT_SYMBOL(atomic64_fetch_add_unless); -- 2.11.0