dlm: fix locking of lockspace list in dlm_scand
The dlm_scand thread needs to lock the list of lockspaces
when going through it.
Signed-off-by: David Teigland <teigland@redhat.com>
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 9e0622a..868e4c9 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -445,6 +445,7 @@
the dlm using this ls */
int ls_create_count; /* create/release refcount */
unsigned long ls_flags; /* LSFL_ */
+ unsigned long ls_scan_time;
struct kobject ls_kobj;
struct dlm_rsbtable *ls_rsbtbl;
diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index ba672fe..d910501 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -212,19 +212,41 @@
kset_unregister(dlm_kset);
}
-static int dlm_scand(void *data)
+static struct dlm_ls *find_ls_to_scan(void)
{
struct dlm_ls *ls;
+ spin_lock(&lslist_lock);
+ list_for_each_entry(ls, &lslist, ls_list) {
+ if (time_after_eq(jiffies, ls->ls_scan_time +
+ dlm_config.ci_scan_secs * HZ)) {
+ spin_unlock(&lslist_lock);
+ return ls;
+ }
+ }
+ spin_unlock(&lslist_lock);
+ return NULL;
+}
+
+static int dlm_scand(void *data)
+{
+ struct dlm_ls *ls;
+ int timeout_jiffies = dlm_config.ci_scan_secs * HZ;
+
while (!kthread_should_stop()) {
- list_for_each_entry(ls, &lslist, ls_list) {
+ ls = find_ls_to_scan();
+ if (ls) {
if (dlm_lock_recovery_try(ls)) {
+ ls->ls_scan_time = jiffies;
dlm_scan_rsbs(ls);
dlm_scan_timeout(ls);
dlm_unlock_recovery(ls);
+ } else {
+ ls->ls_scan_time += HZ;
}
+ } else {
+ schedule_timeout_interruptible(timeout_jiffies);
}
- schedule_timeout_interruptible(dlm_config.ci_scan_secs * HZ);
}
return 0;
}
@@ -418,6 +440,7 @@
ls->ls_lvblen = lvblen;
ls->ls_count = 0;
ls->ls_flags = 0;
+ ls->ls_scan_time = jiffies;
if (flags & DLM_LSFL_TIMEWARN)
set_bit(LSFL_TIMEWARN, &ls->ls_flags);