[v2,3/3] multipath: optimize program startup for frequent invocations

Commit Message

Martin Wilck Aug. 24, 2022, 8:11 a.m. UTC

From: Martin Wilck <[e-mail]>

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 <[e-mail]>
Reviewed-by: Benjamin Marzinski <[e-mail]>
---
 multipath/main.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

Patch

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;