Mercurial > hg > nginx

view src/http/ngx_http_postpone_filter_module.c @ 5569:462ae7eedc68 stable-1.4

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Fixed TCP_DEFER_ACCEPT handling (ticket #353). Backed out 05a56ebb084a, as it turns out that kernel can return connections without any delay if syncookies are used. This basically means we can't assume anything about connections returned with deferred accept set. To solve original problem the 05a56ebb084a tried to solve, i.e. to don't wait longer than needed if a connection was accepted after deferred accept timeout, this patch changes a timeout set with setsockopt(TCP_DEFER_ACCEPT) to 1 second, unconditionally. This is believed to be enough for speed improvements, and doesn't imply major changes to timeouts used. Note that before 2.6.32 connections were dropped after a timeout. Though it is believed that 1s is still appropriate for kernels before 2.6.32, as previously tcp_synack_retries controlled the actual timeout and 1s results in more than 1 minute actual timeout by default.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 28 Jan 2014 15:40:46 +0400
parents 586969d972b9
children f026adb935ad
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>


static ngx_int_t ngx_http_postpone_filter_add(ngx_http_request_t *r,
    ngx_chain_t *in);
static ngx_int_t ngx_http_postpone_filter_init(ngx_conf_t *cf);


static ngx_http_module_t  ngx_http_postpone_filter_module_ctx = {
    NULL,                                  /* preconfiguration */
    ngx_http_postpone_filter_init,         /* postconfiguration */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL,                                  /* merge server configuration */

    NULL,                                  /* create location configuration */
    NULL                                   /* merge location configuration */
};


ngx_module_t  ngx_http_postpone_filter_module = {
    NGX_MODULE_V1,
    &ngx_http_postpone_filter_module_ctx,  /* module context */
    NULL,                                  /* module directives */
    NGX_HTTP_MODULE,                       /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_http_output_body_filter_pt    ngx_http_next_body_filter;


static ngx_int_t
ngx_http_postpone_filter(ngx_http_request_t *r, ngx_chain_t *in)
{
    ngx_connection_t              *c;
    ngx_http_postponed_request_t  *pr;

    c = r->connection;

    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http postpone filter \"%V?%V\" %p", &r->uri, &r->args, in);

    if (r != c->data) {

        if (in) {
            ngx_http_postpone_filter_add(r, in);
            return NGX_OK;
        }

#if 0
        /* TODO: SSI may pass NULL */
        ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                      "http postpone filter NULL inactive request",
                      &r->uri, &r->args);
#endif

        return NGX_OK;
    }

    if (r->postponed == NULL) {

        if (in || c->buffered) {
            return ngx_http_next_body_filter(r->main, in);
        }

        return NGX_OK;
    }

    if (in) {
        ngx_http_postpone_filter_add(r, in);
    }

    do {
        pr = r->postponed;

        if (pr->request) {

            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http postpone filter wake \"%V?%V\"",
                           &pr->request->uri, &pr->request->args);

            r->postponed = pr->next;

            c->data = pr->request;

            return ngx_http_post_request(pr->request, NULL);
        }

        if (pr->out == NULL) {
            ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                          "http postpone filter NULL output",
                          &r->uri, &r->args);

        } else {
            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http postpone filter output \"%V?%V\"",
                           &r->uri, &r->args);

            if (ngx_http_next_body_filter(r->main, pr->out) == NGX_ERROR) {
                return NGX_ERROR;
            }
        }

        r->postponed = pr->next;

    } while (r->postponed);

    return NGX_OK;
}


static ngx_int_t
ngx_http_postpone_filter_add(ngx_http_request_t *r, ngx_chain_t *in)
{
    ngx_http_postponed_request_t  *pr, **ppr;

    if (r->postponed) {
        for (pr = r->postponed; pr->next; pr = pr->next) { /* void */ }

        if (pr->request == NULL) {
            goto found;
        }

        ppr = &pr->next;

    } else {
        ppr = &r->postponed;
    }

    pr = ngx_palloc(r->pool, sizeof(ngx_http_postponed_request_t));
    if (pr == NULL) {
        return NGX_ERROR;
    }

    *ppr = pr;

    pr->request = NULL;
    pr->out = NULL;
    pr->next = NULL;

found:

    if (ngx_chain_add_copy(r->pool, &pr->out, in) == NGX_OK) {
        return NGX_OK;
    }

    return NGX_ERROR;
}


static ngx_int_t
ngx_http_postpone_filter_init(ngx_conf_t *cf)
{
    ngx_http_next_body_filter = ngx_http_top_body_filter;
    ngx_http_top_body_filter = ngx_http_postpone_filter;

    return NGX_OK;
}