X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=command.c;h=bde1458776856d26be371da2e309fb21354c5078;hp=e8f6948437aac8c0f03b538381afc5ea20b55fe4;hb=b184fbf41abbdd68ee148ea4dc6fc2969f05e87b;hpb=030a9d5c9fe28328d5db977bf2c8ddbf7302673d

diff --git a/command.c b/command.c
index e8f69484..bde14587 100644
--- a/command.c
+++ b/command.c
@@ -75,20 +75,14 @@ static void dummy(__a_unused int s)
 {
 }
 
-static void mmd_dup(struct misc_meta_data *new_mmd)
-{
-	mutex_lock(mmd_mutex);
-	*new_mmd = *mmd;
-	mutex_unlock(mmd_mutex);
-}
-
 /*
- * Compute human readable string containing vss status for given integer value.
+ * Compute human readable vss status text.
  *
- * We don't want to use vss_playing() and friends here because we take a
- * snapshot of the mmd struct and use the copy for computing the state of the
- * vss. If the real data were used, we would take the mmd lock for a rather
- * long time or risk to get an inconsistent view.
+ * We can't call vss_playing() and friends here because those functions read
+ * the flags from the primary mmd structure, so calling them from command
+ * handler context would require to take the mmd lock. At the time the function
+ * is called we already took a copy of the mmd structure and want to use the
+ * flags value of the copy for computing the vss status text.
  */
 static char *vss_status_tohuman(unsigned int flags)
 {
@@ -532,7 +526,13 @@ static int com_stat(struct command_context *cc)
 	if (i != cc->argc)
 		return -E_COMMAND_SYNTAX;
 	for (;;) {
-		mmd_dup(nmmd);
+		/*
+		 * Copy the mmd structure to minimize the time we hold the mmd
+		 * lock.
+		 */
+		mutex_lock(mmd_mutex);
+		*nmmd = *mmd;
+		mutex_unlock(mmd_mutex);
 		ret = get_status(nmmd, parser_friendly, &s);
 		ret = send_sb(&cc->scc, s, ret, SBD_OUTPUT, false);
 		if (ret < 0)