Mercurial > hg > nginx
view src/core/ngx_proxy_protocol.h @ 6080:4296627f385a stable-1.6
Core: fixed a race resulting in extra sem_post()'s.
The mtx->wait counter was not decremented if we were able to obtain the lock
right after incrementing it. This resulted in unneeded sem_post() calls,
eventually leading to EOVERFLOW errors being logged, "sem_post() failed
while wake shmtx (75: Value too large for defined data type)".
To close the race, mtx->wait is now decremented if we obtain the lock right
after incrementing it in ngx_shmtx_lock(). The result can become -1 if a
concurrent ngx_shmtx_unlock() decrements mtx->wait before the added code does.
However, that only leads to one extra iteration in the next call of
ngx_shmtx_lock().
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Wed, 04 Feb 2015 16:22:43 +0300 |
parents | 3a72b1805c52 |
children | fa663739e115 |
line wrap: on
line source
/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #ifndef _NGX_PROXY_PROTOCOL_H_INCLUDED_ #define _NGX_PROXY_PROTOCOL_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #define NGX_PROXY_PROTOCOL_MAX_HEADER 107 u_char *ngx_proxy_protocol_parse(ngx_connection_t *c, u_char *buf, u_char *last); #endif /* _NGX_PROXY_PROTOCOL_H_INCLUDED_ */