[dm-devel] [PATCH v2 6/9] multipathd: retrigger uevent for partial paths

[Benjamin Marzinski]

If a partial path appears and is not fully initialized within
180 seconds, trigger a uevent. If the udev device is not initialized
trigger an add event. Otherwise, trigger a change event.

Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
---
 libmultipath/libmultipath.version |  2 +-
 libmultipath/structs.h            |  1 +
 libmultipath/structs_vec.c        |  1 +
 multipathd/main.c                 | 20 ++++++++++++++++++++
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/libmultipath/libmultipath.version b/libmultipath/libmultipath.version
index 6473091d..58a7d1be 100644
--- a/libmultipath/libmultipath.version
+++ b/libmultipath/libmultipath.version
@@ -31,7 +31,7 @@
  *   The new version inherits the previous ones.
  */
 
-LIBMULTIPATH_10.0.0 {
+LIBMULTIPATH_11.0.0 {
 global:
 	/* symbols referenced by multipath and multipathd */
 	add_foreign;
diff --git a/libmultipath/structs.h b/libmultipath/structs.h
index 69409fd4..c21d1eda 100644
--- a/libmultipath/structs.h
+++ b/libmultipath/structs.h
@@ -318,6 +318,7 @@ struct path {
 	int fd;
 	int initialized;
 	int retriggers;
+	int partial_retrigger_delay;
 	unsigned int path_failures;
 	time_t dis_reinstate_time;
 	int disable_reinstate;
diff --git a/libmultipath/structs_vec.c b/libmultipath/structs_vec.c
index 1de9175e..9b6407bd 100644
--- a/libmultipath/structs_vec.c
+++ b/libmultipath/structs_vec.c
@@ -195,6 +195,7 @@ bool update_pathvec_from_dm(vector pathvec, struct multipath *mpp,
 					condlog(2, "%s: adding new path %s",
 						mpp->alias, pp->dev);
 					pp->initialized = INIT_PARTIAL;
+					pp->partial_retrigger_delay = 180;
 					store_path(pathvec, pp);
 					pp->tick = 1;
 				}
diff --git a/multipathd/main.c b/multipathd/main.c
index 8f6be6b9..b0037721 100644
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -1948,6 +1948,25 @@ retry_count_tick(vector mpvec)
 	}
 }
 
+static void
+partial_retrigger_tick(vector pathvec)
+{
+	struct path *pp;
+	unsigned int i;
+
+	vector_foreach_slot (pathvec, pp, i) {
+		if (pp->initialized == INIT_PARTIAL && pp->udev &&
+		    pp->partial_retrigger_delay > 0 &&
+		    --pp->partial_retrigger_delay == 0) {
+			const char *msg = udev_device_get_is_initialized(pp->udev) ?
+					  "change" : "add";
+
+			sysfs_attr_set_value(pp->udev, "uevent", msg,
+					     strlen(msg));
+		}
+	}
+}
+
 int update_prio(struct path *pp, int refresh_all)
 {
 	int oldpriority;
@@ -2566,6 +2585,7 @@ checkerloop (void *ap)
 		retry_count_tick(vecs->mpvec);
 		missing_uev_wait_tick(vecs);
 		ghost_delay_tick(vecs);
+		partial_retrigger_tick(vecs->pathvec);
 		lock_cleanup_pop(vecs->lock);
 
 		if (count)
-- 
2.17.2