Allocate request object from its own pool.

Previously, it was allocated from a connection pool and
was selectively freed for an idle keepalive connection.

The goal is to put coupled things in one chunk of memory,
and to simplify handling of request objects.

diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 0cb081c7448f9fbc9948d1ce2aa3cbcb40a76f69..54e1c262ebfdf6c06b19e12ce5cfd7349250550f 100644 (file)
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -365,6 +365,7 @@ ngx_http_init_connection(ngx_connection_t *c)
 static void
 ngx_http_init_request(ngx_event_t *rev)
 {
+    ngx_pool_t                 *pool;
     ngx_time_t                 *tp;
     ngx_connection_t           *c;
     ngx_http_request_t         *r;
@@ -387,26 +388,24 @@ ngx_http_init_request(ngx_event_t *rev)
 
     hc = c->data;
 
-    r = hc->request;
+    cscf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_core_module);
 
-    if (r) {
-        ngx_memzero(r, sizeof(ngx_http_request_t));
-
-        r->pipeline = hc->pipeline;
+    pool = ngx_create_pool(cscf->request_pool_size, c->log);
+    if (pool == NULL) {
+        ngx_http_close_connection(c);
+        return;
+    }
 
-        if (hc->nbusy) {
-            r->header_in = hc->busy[0];
-        }
+    r = ngx_pcalloc(pool, sizeof(ngx_http_request_t));
+    if (r == NULL) {
+        ngx_destroy_pool(pool);
+        ngx_http_close_connection(c);
+        return;
+    }
 
-    } else {
-        r = ngx_pcalloc(c->pool, sizeof(ngx_http_request_t));
-        if (r == NULL) {
-            ngx_http_close_connection(c);
-            return;
-        }
+    r->pool = pool;
 
-        hc->request = r;
-    }
+    r->pipeline = hc->pipeline;
 
     c->data = r;
     r->http_connection = hc;
@@ -426,27 +425,17 @@ ngx_http_init_request(ngx_event_t *rev)
 
     ngx_http_set_connection_log(r->connection, clcf->error_log);
 
-    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
-
     if (c->buffer == NULL) {
         c->buffer = ngx_create_temp_buf(c->pool,
                                         cscf->client_header_buffer_size);
         if (c->buffer == NULL) {
+            ngx_destroy_pool(r->pool);
             ngx_http_close_connection(c);
             return;
         }
     }
 
-    if (r->header_in == NULL) {
-        r->header_in = c->buffer;
-    }
-
-    r->pool = ngx_create_pool(cscf->request_pool_size, c->log);
-    if (r->pool == NULL) {
-        ngx_http_close_connection(c);
-        return;
-    }
-
+    r->header_in = hc->nbusy ? hc->busy[0] : c->buffer;
 
     if (ngx_list_init(&r->headers_out.headers, r->pool, 20,
                       sizeof(ngx_table_elt_t))
@@ -2663,6 +2652,7 @@ ngx_http_set_keepalive(ngx_http_request_t *r)
         }
     }
 
+    /* guard against recursive call from ngx_http_finalize_connection() */
     r->keepalive = 0;
 
     ngx_http_free_request(r, 0);
@@ -2694,17 +2684,12 @@ ngx_http_set_keepalive(ngx_http_request_t *r)
     hc->pipeline = 0;
 
     /*
-     * To keep a memory footprint as small as possible for an idle
-     * keepalive connection we try to free the ngx_http_request_t and
-     * c->buffer's memory if they were allocated outside the c->pool.
-     * The large header buffers are always allocated outside the c->pool and
-     * are freed too.
+     * To keep a memory footprint as small as possible for an idle keepalive
+     * connection we try to free c->buffer's memory if it was allocated outside
+     * the c->pool.  The large header buffers are always allocated outside the
+     * c->pool and are freed too.
      */
 
-    if (ngx_pfree(c->pool, r) == NGX_OK) {
-        hc->request = NULL;
-    }
-
     b = c->buffer;
 
     if (ngx_pfree(c->pool, b->start) == NGX_OK) {
@@ -3155,6 +3140,7 @@ static void
 ngx_http_free_request(ngx_http_request_t *r, ngx_int_t rc)
 {
     ngx_log_t                 *log;
+    ngx_pool_t                *pool;
     struct linger              linger;
     ngx_http_cleanup_t        *cln;
     ngx_http_log_ctx_t        *ctx;
@@ -3221,7 +3207,15 @@ ngx_http_free_request(ngx_http_request_t *r, ngx_int_t rc)
 
     r->connection->destroyed = 1;
 
-    ngx_destroy_pool(r->pool);
+    /*
+     * Setting r->pool to NULL will increase probability to catch double close
+     * of request since the request object is allocated from its own pool.
+     */
+
+    pool = r->pool;
+    r->pool = NULL;
+
+    ngx_destroy_pool(pool);
 }
 
 

diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 6ddf08e3026f73615afa4eec05e845f47749d095..fd004e8f1d0b2f57b0b26b10d18e3f58ecde1162 100644 (file)
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -302,8 +302,6 @@ typedef struct {
 #endif
 #endif
 
-    ngx_http_request_t               *request;
-
     ngx_buf_t                       **busy;
     ngx_int_t                         nbusy;