Mercurial > hg > nginx
view src/event/ngx_event_acceptex.c @ 6635:6acaa638fa07
Events: support for EPOLLEXCLUSIVE.
This flag appeared in Linux 4.5 and is useful for avoiding thundering herd
problem.
The current Linux kernel implementation walks the list of exclusive waiters,
and queues an event to each epfd, until it finds the first waiter that has
threads blocked on it via epoll_wait().
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Fri, 15 Jul 2016 15:18:57 +0300 |
parents | bcd442b585f0 |
children | fdc3d40979b0 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> static void ngx_close_posted_connection(ngx_connection_t *c); void ngx_event_acceptex(ngx_event_t *rev) { ngx_listening_t *ls; ngx_connection_t *c; c = rev->data; ls = c->listening; c->log->handler = ngx_accept_log_error; ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0, "AcceptEx: %d", c->fd); if (rev->ovlp.error) { ngx_log_error(NGX_LOG_CRIT, c->log, rev->ovlp.error, "AcceptEx() %V failed", &ls->addr_text); return; } /* SO_UPDATE_ACCEPT_CONTEXT is required for shutdown() to work */ if (setsockopt(c->fd, SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT, (char *) &ls->fd, sizeof(ngx_socket_t)) == -1) { ngx_log_error(NGX_LOG_CRIT, c->log, ngx_socket_errno, "setsockopt(SO_UPDATE_ACCEPT_CONTEXT) failed for %V", &c->addr_text); /* TODO: close socket */ return; } ngx_getacceptexsockaddrs(c->buffer->pos, ls->post_accept_buffer_size, ls->socklen + 16, ls->socklen + 16, &c->local_sockaddr, &c->local_socklen, &c->sockaddr, &c->socklen); if (ls->post_accept_buffer_size) { c->buffer->last += rev->available; c->buffer->end = c->buffer->start + ls->post_accept_buffer_size; } else { c->buffer = NULL; } if (ls->addr_ntop) { c->addr_text.data = ngx_pnalloc(c->pool, ls->addr_text_max_len); if (c->addr_text.data == NULL) { /* TODO: close socket */ return; } c->addr_text.len = ngx_sock_ntop(c->sockaddr, c->socklen, c->addr_text.data, ls->addr_text_max_len, 0); if (c->addr_text.len == 0) { /* TODO: close socket */ return; } } ngx_event_post_acceptex(ls, 1); c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1); ls->handler(c); return; } ngx_int_t ngx_event_post_acceptex(ngx_listening_t *ls, ngx_uint_t n) { u_long rcvd; ngx_err_t err; ngx_log_t *log; ngx_uint_t i; ngx_event_t *rev, *wev; ngx_socket_t s; ngx_connection_t *c; for (i = 0; i < n; i++) { /* TODO: look up reused sockets */ s = ngx_socket(ls->sockaddr->sa_family, ls->type, 0); ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &ls->log, 0, ngx_socket_n " s:%d", s); if (s == (ngx_socket_t) -1) { ngx_log_error(NGX_LOG_ALERT, &ls->log, ngx_socket_errno, ngx_socket_n " failed"); return NGX_ERROR; } c = ngx_get_connection(s, &ls->log); if (c == NULL) { return NGX_ERROR; } c->pool = ngx_create_pool(ls->pool_size, &ls->log); if (c->pool == NULL) { ngx_close_posted_connection(c); return NGX_ERROR; } log = ngx_palloc(c->pool, sizeof(ngx_log_t)); if (log == NULL) { ngx_close_posted_connection(c); return NGX_ERROR; } c->buffer = ngx_create_temp_buf(c->pool, ls->post_accept_buffer_size + 2 * (ls->socklen + 16)); if (c->buffer == NULL) { ngx_close_posted_connection(c); return NGX_ERROR; } c->local_sockaddr = ngx_palloc(c->pool, ls->socklen); if (c->local_sockaddr == NULL) { ngx_close_posted_connection(c); return NGX_ERROR; } c->sockaddr = ngx_palloc(c->pool, ls->socklen); if (c->sockaddr == NULL) { ngx_close_posted_connection(c); return NGX_ERROR; } *log = ls->log; c->log = log; c->recv = ngx_recv; c->send = ngx_send; c->recv_chain = ngx_recv_chain; c->send_chain = ngx_send_chain; c->listening = ls; rev = c->read; wev = c->write; rev->ovlp.event = rev; wev->ovlp.event = wev; rev->handler = ngx_event_acceptex; rev->ready = 1; wev->ready = 1; rev->log = c->log; wev->log = c->log; if (ngx_add_event(rev, 0, NGX_IOCP_IO) == NGX_ERROR) { ngx_close_posted_connection(c); return NGX_ERROR; } if (ngx_acceptex(ls->fd, s, c->buffer->pos, ls->post_accept_buffer_size, ls->socklen + 16, ls->socklen + 16, &rcvd, (LPOVERLAPPED) &rev->ovlp) == 0) { err = ngx_socket_errno; if (err != WSA_IO_PENDING) { ngx_log_error(NGX_LOG_ALERT, &ls->log, err, "AcceptEx() %V failed", &ls->addr_text); ngx_close_posted_connection(c); return NGX_ERROR; } } } return NGX_OK; } static void ngx_close_posted_connection(ngx_connection_t *c) { ngx_socket_t fd; ngx_free_connection(c); fd = c->fd; c->fd = (ngx_socket_t) -1; if (ngx_close_socket(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, c->log, ngx_socket_errno, ngx_close_socket_n " failed"); } if (c->pool) { ngx_destroy_pool(c->pool); } } u_char * ngx_acceptex_log_error(ngx_log_t *log, u_char *buf, size_t len) { return ngx_snprintf(buf, len, " while posting AcceptEx() on %V", log->data); }