diff options
Diffstat (limited to 'src/core/ngx_spinlock.c')
| -rw-r--r-- | src/core/ngx_spinlock.c | 33 |
1 files changed, 16 insertions, 17 deletions
diff --git a/src/core/ngx_spinlock.c b/src/core/ngx_spinlock.c index a3082a0a5..f6c80f769 100644 --- a/src/core/ngx_spinlock.c +++ b/src/core/ngx_spinlock.c @@ -8,36 +8,35 @@ #include <ngx_core.h> -/* - * TODO: the P4 optimized assembler version with the "pause" operation - */ - void -ngx_spinlock(ngx_atomic_t *lock, ngx_uint_t spin) +ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin) { #if (NGX_HAVE_ATOMIC_OPS) - ngx_uint_t tries; - - tries = 0; + ngx_uint_t i, n; for ( ;; ) { - if (*lock) { - if (ngx_ncpu > 1 && tries++ < spin) { - continue; - } + if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { + return; + } - ngx_sched_yield(); + if (ngx_ncpu > 1) { - tries = 0; + for (n = 1; n < spin; n <<= 1) { - } else { - if (ngx_atomic_cmp_set(lock, 0, 1)) { - return; + for (i = 0; i < n; i++) { + ngx_cpu_pause(); + } + + if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { + return; + } } } + + ngx_sched_yield(); } #else |