[GNUnet-SVN] r15740 - in libmicrohttpd: . src/daemon

[gnunet]

Author: grothoff
Date: 2011-06-22 10:38:48 +0200 (Wed, 22 Jun 2011)
New Revision: 15740

Modified:
   libmicrohttpd/ChangeLog
   libmicrohttpd/src/daemon/daemon.c
Log:
improve performance by using shutdown on client sockets instead of poll/select 
on listen socket

Modified: libmicrohttpd/ChangeLog
===================================================================
--- libmicrohttpd/ChangeLog     2011-06-22 08:28:49 UTC (rev 15739)
+++ libmicrohttpd/ChangeLog     2011-06-22 08:38:48 UTC (rev 15740)
@@ -1,3 +1,8 @@
+Wed Jun 22 10:37:35 CEST 2011
+       Removing listen socket from poll/select sets in
+       MHD_USE_THREAD_PER_CONNECTION mode; using 'shutdown'
+       on connection sockets to signal termination instead. -CG
+
 Wed Jun 22 10:25:13 CEST 2011
        Eliminate unnecessary (and badly synchronized) calls to
        MHD_get_timeout in MHD_USE_THREAD_PER_CONNECTION mode.
@@ -7,7 +12,7 @@
        Fixing tiny memory leak in SSL code from 'gnutls_priority_init'.
        Fixing data race between code doing connection shutdown and
        connection cleanup.
-       Changing code to reduce connection cleanup cost from O(n) to O(1). 
+       Changing code to reduce connection cleanup cost from O(n) to O(1).
        Cleaning up logging code around 'connection_close_error'. -CG
 
 Sat Jun 11 13:05:12 CEST 2011

Modified: libmicrohttpd/src/daemon/daemon.c
===================================================================
--- libmicrohttpd/src/daemon/daemon.c   2011-06-22 08:28:49 UTC (rev 15739)
+++ libmicrohttpd/src/daemon/daemon.c   2011-06-22 08:38:48 UTC (rev 15740)
@@ -563,14 +563,13 @@
   fd_set ws;
   fd_set es;
   int max;
-  int fd;
   struct timeval tv;
   struct timeval *tvp;
   unsigned int timeout;
   time_t now;
 #ifdef HAVE_POLL_H
   struct MHD_Pollfd mp;
-  struct pollfd p[2];
+  struct pollfd p[1];
 #endif
 
   timeout = con->daemon->connection_timeout;
@@ -605,15 +604,7 @@
          FD_ZERO (&rs);
          FD_ZERO (&ws);
          FD_ZERO (&es);
-         if (-1 != (fd = con->daemon->socket_fd))
-           {
-             /* we add the listen socket to our read set so
-                that if the server is shutdown, we notice it */
-             max = fd;
-             FD_SET (fd, &rs);
-           }
-         else
-           max = 0;
+         max = 0;
          MHD_connection_get_fdset (con, &rs, &ws, &es, &max);
          num_ready = SELECT (max + 1, &rs, &ws, &es, tvp);
          if (num_ready < 0) 
@@ -648,20 +639,11 @@
            p[0].events |= POLLIN;        
          if (mp.events & MHD_POLL_ACTION_OUT) 
            p[0].events |= POLLOUT;
-         /* we add the listen socket to our read set so
-            that if the server is shutdown, we notice it */
-
-         fd = con->daemon->socket_fd;
-         p[1].fd = fd;
-         p[1].events = 0; /* only care about POLLHUP */
-         
          if (poll (p, 
-                   (fd != -1) ? 2 : 1, 
+                   1, 
                    (tvp == NULL) 
                    ? -1 
-                   : ((fd != -1) 
-                      ? (tv.tv_sec * 1000) 
-                      : 0)) < 0) 
+                   : tv.tv_sec * 1000) < 0)
            {
              if (errno == EINTR)
                continue;
@@ -2407,7 +2389,27 @@
   struct MHD_Connection *pos;
   void *unused;
   int rc;
+  
+  /* first, make sure all threads are aware of shutdown; need to
+     traverse DLLs in peace... */
+  if (0 != pthread_mutex_lock(&daemon->cleanup_connection_mutex))
+    {
+#if HAVE_MESSAGES
+      MHD_DLOG (daemon, "Failed to acquire cleanup mutex\n");
+#endif
+      abort();
+    }
+  for (pos = daemon->connections_head; pos != NULL; pos = pos->next)    
+    SHUTDOWN (pos->socket_fd, SHUT_RDWR);    
+  if (0 != pthread_mutex_unlock(&daemon->cleanup_connection_mutex))
+    {
+#if HAVE_MESSAGES
+      MHD_DLOG (daemon, "Failed to release cleanup mutex\n");
+#endif
+      abort();
+    }
 
+  /* now, collect threads */
   if (0 != (daemon->options & MHD_USE_THREAD_PER_CONNECTION))
     {
       while (NULL != (pos = daemon->connections_head))
@@ -2423,6 +2425,8 @@
          pos->thread_joined = MHD_YES;
        }
     }
+
+  /* now that we're alone, move everyone to cleanup */
   while (NULL != (pos = daemon->connections_head))
     {
       pos->state = MHD_CONNECTION_CLOSED;
@@ -2485,6 +2489,7 @@
     }
   free (daemon->worker_pool);
 
+  /* clean up master threads */
   if ((0 != (daemon->options & MHD_USE_THREAD_PER_CONNECTION)) ||
       ((0 != (daemon->options & MHD_USE_SELECT_INTERNALLY))
         && (0 == daemon->worker_pool_size)))