From 44701cf732ba6f3f49cc1bd6113889e28fab907e Mon Sep 17 00:00:00 2001 From: Hans Petter Selasky Date: Mon, 23 May 2016 16:19:51 +0000 Subject: [PATCH] Implement "atomic_long_add_unless()" in the LinuxKPI and fix the implementation of "atomic_long_inc_not_zero()". Found by: ngie @ MFC after: 1 week Sponsored by: Mellanox Technologies --- .../linuxkpi/common/include/asm/atomic-long.h | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/sys/compat/linuxkpi/common/include/asm/atomic-long.h b/sys/compat/linuxkpi/common/include/asm/atomic-long.h index 90187fcdaf4..6fbdc5e5556 100644 --- a/sys/compat/linuxkpi/common/include/asm/atomic-long.h +++ b/sys/compat/linuxkpi/common/include/asm/atomic-long.h @@ -41,7 +41,7 @@ typedef struct { #define atomic_long_add(i, v) atomic_long_add_return((i), (v)) #define atomic_long_inc_return(v) atomic_long_add_return(1, (v)) -#define atomic_long_inc_not_zero(v) atomic_long_inc_not_zero(v) +#define atomic_long_inc_not_zero(v) atomic_long_add_unless((v), 1, 0) static inline long atomic_long_add_return(long i, atomic_long_t *v) @@ -73,6 +73,21 @@ atomic_long_dec(atomic_long_t *v) return atomic_fetchadd_long(&v->counter, -1) - 1; } +static inline int +atomic_long_add_unless(atomic_long_t *v, long a, long u) +{ + long c; + + for (;;) { + c = atomic_long_read(v); + if (unlikely(c == u)) + break; + if (likely(atomic_cmpset_long(&v->counter, c, c + a))) + break; + } + return (c != u); +} + static inline long atomic_long_dec_and_test(atomic_long_t *v) {