[libvirt] [PATCH 3/3] sanlock: Properly init io_timeout
https://bugzilla.redhat.com/show_bug.cgi?id=1292984
Hold on to your hats, because this is gonna be wild.
In bd3e16a3 I've tried to expose sanlock io_timeout. What I had
not realized (because there is like no documentation for sanlock
at all) was very unusual way their APIs work. Basically, what we
do currently is:
sanlock_add_lockspace_timeout(&ls, io_timeout);
which adds a lockspace to sanlock daemon. One would expect that
io_timeout sets the io_timeout for it. Nah! That's where you are
completely off the tracks. It sets timeout for next lockspace you
will probably add later. Therefore:
sanlock_add_lockspace_timeout(&ls, io_timeout = 10);
/* adds new lockspace with default io_timeout */
sanlock_add_lockspace_timeout(&ls, io_timeout = 20);
/* adds new lockspace with io_timeout = 10 */
sanlock_add_lockspace_timeout(&ls, io_timeout = 40);
/* adds new lockspace with io_timeout = 20 */
And so on. You get the picture.
Fortunately, we don't allow setting io_timeout per domain or per
domain disk. So we just need to set the default used in the very
first step and hope for the best (as all the io_timeout-s used
later will have the same value).
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/locking/lock_driver_sanlock.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/src/locking/lock_driver_sanlock.c b/src/locking/lock_driver_sanlock.c
index f09027f..ee1ee67 100644
--- a/src/locking/lock_driver_sanlock.c
+++ b/src/locking/lock_driver_sanlock.c
@@ -157,6 +157,29 @@ static int
virLockManagerSanlockLoadConfig(virLockManagerSanlockDriverPtr driver
return ret;
}
+static int
+virLockManagerSanlockInitLockspace(virLockManagerSanlockDriverPtr driver,
+ struct sanlk_lockspace *ls)
+{
+ int ret;
+
+#ifdef HAVE_SANLOCK_IO_TIMEOUT
+ const int max_hosts = 0; /* defaults used in sanlock_init() implementation */
+ const unsigned int lockspaceFlags = 0;
+
+ ret = sanlock_write_lockspace(ls, max_hosts, lockspaceFlags, driver->io_timeout);
+#else
+ if (driver->io_timeout) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+ _("unable to use io_timeout with this version of
sanlock"));
+ return -ENOTSUP;
+ }
+
+ ret = sanlock_init(ls, NULL, 0, 0);
+#endif
+ return ret;
+}
+
/* How much ms sleep before retrying to add a lockspace? */
#define LOCKSPACE_SLEEP 100
/* How many times try adding a lockspace? */
@@ -267,7 +290,7 @@ virLockManagerSanlockSetupLockspace(virLockManagerSanlockDriverPtr
driver)
goto error_unlink;
}
- if ((rv = sanlock_init(&ls, NULL, 0, 0)) < 0) {
+ if ((rv = virLockManagerSanlockInitLockspace(driver, &ls) < 0)) {
if (rv <= -200)
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Unable to initialize lockspace %s: error
%d"),
--
2.8.4