When -z <jitter> is specified, some updates may be timestamped up to

[rrdtool.git] / src / rrd_daemon.c

diff --git a/src/rrd_daemon.c b/src/rrd_daemon.c
index c438028..f1b8f8b 100644 (file)
--- a/src/rrd_daemon.c
+++ b/src/rrd_daemon.c
@@ -119,7 +119,7 @@ struct cache_item_s
 #define CI_FLAGS_IN_TREE  (1<<0)
 #define CI_FLAGS_IN_QUEUE (1<<1)
   int flags;
-
+  pthread_cond_t  flushed;
   cache_item_t *next;
 };
 
@@ -165,8 +165,6 @@ static cache_item_t   *cache_queue_tail = NULL;
 static pthread_mutex_t cache_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t  cache_cond = PTHREAD_COND_INITIALIZER;
 
-static pthread_cond_t  flush_cond = PTHREAD_COND_INITIALIZER;
-
 static int config_write_interval = 300;
 static int config_write_jitter   = 0;
 static int config_flush_interval = 3600;
@@ -211,31 +209,34 @@ static void sig_term_handler (int s __attribute__((unused))) /* {{{ */
   pthread_cond_broadcast(&cache_cond);
 } /* }}} void sig_term_handler */
 
-static int write_pidfile (void) /* {{{ */
+static int open_pidfile(void) /* {{{ */
 {
-  pid_t pid;
-  char *file;
   int fd;
-  FILE *fh;
+  char *file;
 
-  pid = getpid ();
-  
   file = (config_pid_file != NULL)
     ? config_pid_file
     : LOCALSTATEDIR "/run/rrdcached.pid";
 
   fd = open(file, O_CREAT|O_EXCL|O_WRONLY, S_IRUSR|S_IRGRP|S_IROTH);
   if (fd < 0)
-  {
-    RRDD_LOG(LOG_ERR, "FATAL: cannot create '%s' (%s)",
-             file, rrd_strerror(errno));
-    return (-1);
-  }
+    fprintf(stderr, "FATAL: cannot create '%s' (%s)\n",
+            file, rrd_strerror(errno));
+
+  return(fd);
+}
+
+static int write_pidfile (int fd) /* {{{ */
+{
+  pid_t pid;
+  FILE *fh;
+
+  pid = getpid ();
 
   fh = fdopen (fd, "w");
   if (fh == NULL)
   {
-    RRDD_LOG (LOG_ERR, "write_pidfile: Opening `%s' failed.", file);
+    RRDD_LOG (LOG_ERR, "write_pidfile: fdopen() failed.");
     close(fd);
     return (-1);
   }
@@ -499,7 +500,7 @@ static int flush_old_values (int max_age)
   if (max_age > 0)
     cfd.abs_timeout = cfd.now - max_age;
   else
-    cfd.abs_timeout = cfd.now + 1;
+    cfd.abs_timeout = cfd.now + 2*config_write_jitter + 1;
 
   /* `tree_callback_flush' will return the keys of all values that haven't
    * been touched in the last `config_flush_interval' seconds in `cfd'.
@@ -640,6 +641,7 @@ static void *queue_thread_main (void *args __attribute__((unused))) /* {{{ */
     }
 
     journal_write("wrote", file);
+    pthread_cond_broadcast(&ci->flushed);
 
     for (i = 0; i < values_num; i++)
       free (values[i]);
@@ -656,7 +658,6 @@ static void *queue_thread_main (void *args __attribute__((unused))) /* {{{ */
     }
 
     pthread_mutex_lock (&cache_lock);
-    pthread_cond_broadcast (&flush_cond);
 
     /* We're about to shut down, so lets flush the entire tree. */
     if ((do_shutdown != 0) && (cache_queue_head == NULL))
@@ -751,23 +752,9 @@ static int flush_file (const char *filename) /* {{{ */
   enqueue_cache_item (ci, HEAD);
   pthread_cond_signal (&cache_cond);
 
-  while ((ci->flags & CI_FLAGS_IN_QUEUE) != 0)
-  {
-    ci = NULL;
-
-    pthread_cond_wait (&flush_cond, &cache_lock);
-
-    ci = g_tree_lookup (cache_tree, filename);
-    if (ci == NULL)
-    {
-      RRDD_LOG (LOG_ERR, "flush_file: Tree node went away "
-          "while waiting for flush.");
-      pthread_mutex_unlock (&cache_lock);
-      return (-1);
-    }
-  }
+  pthread_cond_wait(&ci->flushed, &cache_lock);
+  pthread_mutex_unlock(&cache_lock);
 
-  pthread_mutex_unlock (&cache_lock);
   return (0);
 } /* }}} int flush_file */
 
@@ -1043,17 +1030,19 @@ static int handle_request_update (int fd, /* {{{ */
   pthread_mutex_unlock(&stats_lock);
 
   pthread_mutex_lock (&cache_lock);
-
   ci = g_tree_lookup (cache_tree, file);
+
   if (ci == NULL) /* {{{ */
   {
     struct stat statbuf;
 
+    /* don't hold the lock while we setup; stat(2) might block */
+    pthread_mutex_unlock(&cache_lock);
+
     memset (&statbuf, 0, sizeof (statbuf));
     status = stat (file, &statbuf);
     if (status != 0)
     {
-      pthread_mutex_unlock (&cache_lock);
       RRDD_LOG (LOG_NOTICE, "handle_request_update: stat (%s) failed.", file);
 
       status = errno;
@@ -1067,16 +1056,12 @@ static int handle_request_update (int fd, /* {{{ */
     }
     if (!S_ISREG (statbuf.st_mode))
     {
-      pthread_mutex_unlock (&cache_lock);
-
       snprintf (answer, sizeof (answer), "-1 Not a regular file: %s\n", file);
       RRDD_UPDATE_SEND;
       return (0);
     }
     if (access(file, R_OK|W_OK) != 0)
     {
-      pthread_mutex_unlock (&cache_lock);
-
       snprintf (answer, sizeof (answer), "-1 Cannot read/write %s: %s\n",
                 file, rrd_strerror(errno));
       RRDD_UPDATE_SEND;
@@ -1086,7 +1071,6 @@ static int handle_request_update (int fd, /* {{{ */
     ci = (cache_item_t *) malloc (sizeof (cache_item_t));
     if (ci == NULL)
     {
-      pthread_mutex_unlock (&cache_lock);
       RRDD_LOG (LOG_ERR, "handle_request_update: malloc failed.");
 
       strncpy (answer, "-1 malloc failed.\n", sizeof (answer));
@@ -1098,7 +1082,6 @@ static int handle_request_update (int fd, /* {{{ */
     ci->file = strdup (file);
     if (ci->file == NULL)
     {
-      pthread_mutex_unlock (&cache_lock);
       free (ci);
       RRDD_LOG (LOG_ERR, "handle_request_update: strdup failed.");
 
@@ -1110,6 +1093,7 @@ static int handle_request_update (int fd, /* {{{ */
     _wipe_ci_values(ci, now);
     ci->flags = CI_FLAGS_IN_TREE;
 
+    pthread_mutex_lock(&cache_lock);
     g_tree_insert (cache_tree, (void *) ci->file, (void *) ci);
   } /* }}} */
   assert (ci != NULL);
@@ -1835,6 +1819,7 @@ static void *listen_thread_main (void *args __attribute__((unused))) /* {{{ */
 static int daemonize (void) /* {{{ */
 {
   int status;
+  int fd;
 
   /* These structures are static, because `sigaction' behaves weird if the are
    * overwritten.. */
@@ -1842,6 +1827,9 @@ static int daemonize (void) /* {{{ */
   static struct sigaction sa_term;
   static struct sigaction sa_pipe;
 
+  fd = open_pidfile();
+  if (fd < 0) return fd;
+
   if (!stay_foreground)
   {
     pid_t child;
@@ -1905,7 +1893,7 @@ static int daemonize (void) /* {{{ */
     return (-1);
   }
 
-  status = write_pidfile ();
+  status = write_pidfile (fd);
   return status;
 } /* }}} int daemonize */