Mercurial > hg > nginx-quic
view src/core/ngx_spinlock.c @ 6794:93b294c5d581
Upstream: avoid holding a cache node with upgraded connections.
Holding a cache node lock doesn't make sense as we can't use caching
anyway, and results in "ignore long locked inactive cache entry" alerts
if a node is locked for a long time.
The same is done for unbuffered connections, as they can be alive for
a long time as well.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 03 Nov 2016 17:09:32 +0300 |
parents | f737e406aa68 |
children |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> void ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin) { #if (NGX_HAVE_ATOMIC_OPS) ngx_uint_t i, n; for ( ;; ) { if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { return; } if (ngx_ncpu > 1) { for (n = 1; n < spin; n <<= 1) { for (i = 0; i < n; i++) { ngx_cpu_pause(); } if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) { return; } } } ngx_sched_yield(); } #else #if (NGX_THREADS) #error ngx_spinlock() or ngx_atomic_cmp_set() are not defined ! #endif #endif }