multipath will try to get the priority from a PATH_DOWN path, if the
path doesn't currently have a valid priority. However, if the priority
code needs to contact the device to get the priority, this is likely to
fail for PATH_DOWN paths. This code dates back to when multipathd could
not easily reload device tables with failed paths, so getting the
correct priority was important to have a correctly configured device.
Now multipathd can simply reload the device to move the path to the
correct pathgroup when the path comes back up. Since there are a number
of prioritizers that don't require talking to the device, multipath
shouldn't completely skip attempting to get the priority of these paths,
but it should set a small timeout, so that it isn't hanging in the
case where it needs to contact a device through a failed path.
Signed-off-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx>
---
libmultipath/discovery.c | 14 ++++++--------
libmultipath/prio.c | 6 +++---
2 files changed, 9 insertions(+), 11 deletions(-)
diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c
index bee5b77b..5e88d980 100644
--- a/libmultipath/discovery.c
+++ b/libmultipath/discovery.c
@@ -1667,11 +1667,10 @@ get_state (struct path * pp, struct config *conf, int daemon, int oldstate)
}
static int
-get_prio (struct path * pp)
+get_prio (struct path * pp, int timeout)
{
struct prio * p;
struct config *conf;
- int checker_timeout;
int old_prio;
if (!pp)
@@ -1690,11 +1689,8 @@ get_prio (struct path * pp)
return 1;
}
}
- conf = get_multipath_config();
- checker_timeout = conf->checker_timeout;
- put_multipath_config(conf);
old_prio = pp->priority;
- pp->priority = prio_getprio(p, pp, checker_timeout);
+ pp->priority = prio_getprio(p, pp, timeout);
if (pp->priority < 0) {
/* this changes pp->offline, but why not */
int state = path_offline(pp);
@@ -2101,11 +2097,13 @@ int pathinfo(struct path *pp, struct config *conf, int mask)
/*
* Retrieve path priority, even for PATH_DOWN paths if it has never
- * been successfully obtained before.
+ * been successfully obtained before. If path is down don't try
+ * for too long.
*/
if ((mask & DI_PRIO) && path_state == PATH_UP && strlen(pp->wwid)) {
if (pp->state != PATH_DOWN || pp->priority == PRIO_UNDEF) {
- get_prio(pp);
+ get_prio(pp, (pp->state != PATH_DOWN)?
+ (conf->checker_timeout * 1000) : 10);
}
}
diff --git a/libmultipath/prio.c b/libmultipath/prio.c
index 87de1f97..194563c4 100644
--- a/libmultipath/prio.c
+++ b/libmultipath/prio.c
@@ -10,11 +10,11 @@
static LIST_HEAD(prioritizers);
-unsigned int get_prio_timeout(unsigned int checker_timeout,
+unsigned int get_prio_timeout(unsigned int timeout_ms,
unsigned int default_timeout)
{
- if (checker_timeout)
- return checker_timeout * 1000;
+ if (timeout_ms)
+ return timeout_ms;
return default_timeout;
}
--
2.17.2
--
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