Mercurial > hg > nginx-quic
view src/core/ngx_shmtx.c @ 4182:75d2388bd6b9
Tweaked error messages.
author | Ruslan Ermilov <ru@nginx.com> |
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date | Fri, 07 Oct 2011 07:57:24 +0000 |
parents | 0daede16d68b |
children | 3f6040cd731e 4919fb357a5d |
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/* * Copyright (C) Igor Sysoev */ #include <ngx_config.h> #include <ngx_core.h> #if (NGX_HAVE_ATOMIC_OPS) ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, void *addr, u_char *name) { mtx->lock = addr; if (mtx->spin == (ngx_uint_t) -1) { return NGX_OK; } mtx->spin = 2048; #if (NGX_HAVE_POSIX_SEM) if (sem_init(&mtx->sem, 1, 0) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno, "sem_init() failed"); } else { mtx->semaphore = 1; } #endif return NGX_OK; } void ngx_shmtx_destory(ngx_shmtx_t *mtx) { #if (NGX_HAVE_POSIX_SEM) if (mtx->semaphore) { if (sem_destroy(&mtx->sem) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno, "sem_destroy() failed"); } } #endif } ngx_uint_t ngx_shmtx_trylock(ngx_shmtx_t *mtx) { ngx_atomic_uint_t val; val = *mtx->lock; return ((val & 0x80000000) == 0 && ngx_atomic_cmp_set(mtx->lock, val, val | 0x80000000)); } void ngx_shmtx_lock(ngx_shmtx_t *mtx) { ngx_uint_t i, n; ngx_atomic_uint_t val; ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0, "shmtx lock"); for ( ;; ) { val = *mtx->lock; if ((val & 0x80000000) == 0 && ngx_atomic_cmp_set(mtx->lock, val, val | 0x80000000)) { return; } if (ngx_ncpu > 1) { for (n = 1; n < mtx->spin; n <<= 1) { for (i = 0; i < n; i++) { ngx_cpu_pause(); } val = *mtx->lock; if ((val & 0x80000000) == 0 && ngx_atomic_cmp_set(mtx->lock, val, val | 0x80000000)) { return; } } } #if (NGX_HAVE_POSIX_SEM) if (mtx->semaphore) { val = *mtx->lock; if ((val & 0x80000000) && ngx_atomic_cmp_set(mtx->lock, val, val + 1)) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0, "shmtx wait %XA", val); while (sem_wait(&mtx->sem) == -1) { ngx_err_t err; err = ngx_errno; if (err != NGX_EINTR) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, err, "sem_wait() failed while waiting on shmtx"); break; } } ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0, "shmtx awoke"); } continue; } #endif ngx_sched_yield(); } } void ngx_shmtx_unlock(ngx_shmtx_t *mtx) { ngx_atomic_uint_t val, old, wait; if (mtx->spin != (ngx_uint_t) -1) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0, "shmtx unlock"); } for ( ;; ) { old = *mtx->lock; wait = old & 0x7fffffff; val = wait ? wait - 1 : 0; if (ngx_atomic_cmp_set(mtx->lock, old, val)) { break; } } #if (NGX_HAVE_POSIX_SEM) if (wait == 0 || !mtx->semaphore) { return; } ngx_log_debug1(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0, "shmtx wake %XA", old); if (sem_post(&mtx->sem) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno, "sem_post() failed while wake shmtx"); } #endif } #else ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, void *addr, u_char *name) { if (mtx->name) { if (ngx_strcmp(name, mtx->name) == 0) { mtx->name = name; return NGX_OK; } ngx_shmtx_destory(mtx); } mtx->fd = ngx_open_file(name, NGX_FILE_RDWR, NGX_FILE_CREATE_OR_OPEN, NGX_FILE_DEFAULT_ACCESS); if (mtx->fd == NGX_INVALID_FILE) { ngx_log_error(NGX_LOG_EMERG, ngx_cycle->log, ngx_errno, ngx_open_file_n " \"%s\" failed", name); return NGX_ERROR; } if (ngx_delete_file(name) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno, ngx_delete_file_n " \"%s\" failed", name); } mtx->name = name; return NGX_OK; } void ngx_shmtx_destory(ngx_shmtx_t *mtx) { if (ngx_close_file(mtx->fd) == NGX_FILE_ERROR) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_errno, ngx_close_file_n " \"%s\" failed", mtx->name); } } ngx_uint_t ngx_shmtx_trylock(ngx_shmtx_t *mtx) { ngx_err_t err; err = ngx_trylock_fd(mtx->fd); if (err == 0) { return 1; } if (err == NGX_EAGAIN) { return 0; } #if __osf__ /* Tru64 UNIX */ if (err == NGX_EACCESS) { return 0; } #endif ngx_log_abort(err, ngx_trylock_fd_n " %s failed", mtx->name); return 0; } void ngx_shmtx_lock(ngx_shmtx_t *mtx) { ngx_err_t err; err = ngx_lock_fd(mtx->fd); if (err == 0) { return; } ngx_log_abort(err, ngx_lock_fd_n " %s failed", mtx->name); } void ngx_shmtx_unlock(ngx_shmtx_t *mtx) { ngx_err_t err; err = ngx_unlock_fd(mtx->fd); if (err == 0) { return; } ngx_log_abort(err, ngx_unlock_fd_n " %s failed", mtx->name); } #endif