[dm-devel] [PATCH v3 5/5] multipath: optimize program startup for frequent invocations

[mwilck at suse.com]

From: Martin Wilck <mwilck at suse.com>

Neither "multipath -u" nor "multipath -U" need initialization of the
prioritizers, checkers, and foreign libraries. Also, these commands
need not fail if the bindings file is inconsistent. Move these
possibly slow initialization steps after these special command
invocations.

Signed-off-by: Martin Wilck <mwilck at suse.com>
Reviewed-by: Benjamin Marzinski <bmarzins at redhat.com>
---
 multipath/main.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/multipath/main.c b/multipath/main.c
index 034dd2f..8e5154a 100644
--- a/multipath/main.c
+++ b/multipath/main.c
@@ -957,11 +957,6 @@ main (int argc, char *argv[])
 		exit(RTVL_FAIL);
 	}
 
-	if (check_alias_settings(conf)) {
-		fprintf(stderr, "fatal configuration error, aborting");
-		exit(RTVL_FAIL);
-	}
-
 	if (optind < argc) {
 		dev = calloc(1, FILE_NAME_SIZE);
 
@@ -988,20 +983,9 @@ main (int argc, char *argv[])
 
 	libmp_udev_set_sync_support(1);
 
-	if (init_checkers()) {
-		condlog(0, "failed to initialize checkers");
-		goto out;
-	}
-	if (init_prio()) {
-		condlog(0, "failed to initialize prioritizers");
-		goto out;
-	}
-
 	if ((cmd == CMD_LIST_SHORT || cmd == CMD_LIST_LONG) && enable_foreign)
 		conf->enable_foreign = strdup("");
 
-	/* Failing here is non-fatal */
-	init_foreign(conf->enable_foreign);
 	if (cmd == CMD_USABLE_PATHS) {
 		r = check_usable_paths(conf, dev, dev_type) ?
 			RTVL_FAIL : RTVL_OK;
@@ -1036,6 +1020,23 @@ main (int argc, char *argv[])
 		break;
 	}
 
+	if (check_alias_settings(conf)) {
+		fprintf(stderr, "fatal configuration error, aborting");
+		exit(RTVL_FAIL);
+	}
+
+	if (init_checkers()) {
+		condlog(0, "failed to initialize checkers");
+		goto out;
+	}
+	if (init_prio()) {
+		condlog(0, "failed to initialize prioritizers");
+		goto out;
+	}
+
+	/* Failing here is non-fatal */
+	init_foreign(conf->enable_foreign);
+
 	if (cmd == CMD_RESET_WWIDS) {
 		struct multipath * mpp;
 		int i;
-- 
2.37.1