dlm: fix unlock balance warnings
The in_recovery rw_semaphore has always been acquired and
released by different threads by design. To work around
the "BUG: bad unlock balance detected!" messages, adjust
things so the dlm_recoverd thread always does both down_write
and up_write.
Signed-off-by: David Teigland <teigland@redhat.com>
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 9d3e485..871c1ab 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -604,6 +604,7 @@
struct idr ls_recover_idr;
spinlock_t ls_recover_idr_lock;
wait_queue_head_t ls_wait_general;
+ wait_queue_head_t ls_recover_lock_wait;
struct mutex ls_clear_proc_locks;
struct list_head ls_root_list; /* root resources */
@@ -616,15 +617,40 @@
char ls_name[1];
};
-#define LSFL_WORK 0
-#define LSFL_RUNNING 1
-#define LSFL_RECOVERY_STOP 2
-#define LSFL_RCOM_READY 3
-#define LSFL_RCOM_WAIT 4
-#define LSFL_UEVENT_WAIT 5
-#define LSFL_TIMEWARN 6
-#define LSFL_CB_DELAY 7
-#define LSFL_NODIR 8
+/*
+ * LSFL_RECOVER_STOP - dlm_ls_stop() sets this to tell dlm recovery routines
+ * that they should abort what they're doing so new recovery can be started.
+ *
+ * LSFL_RECOVER_DOWN - dlm_ls_stop() sets this to tell dlm_recoverd that it
+ * should do down_write() on the in_recovery rw_semaphore. (doing down_write
+ * within dlm_ls_stop causes complaints about the lock acquired/released
+ * in different contexts.)
+ *
+ * LSFL_RECOVER_LOCK - dlm_recoverd holds the in_recovery rw_semaphore.
+ * It sets this after it is done with down_write() on the in_recovery
+ * rw_semaphore and clears it after it has released the rw_semaphore.
+ *
+ * LSFL_RECOVER_WORK - dlm_ls_start() sets this to tell dlm_recoverd that it
+ * should begin recovery of the lockspace.
+ *
+ * LSFL_RUNNING - set when normal locking activity is enabled.
+ * dlm_ls_stop() clears this to tell dlm locking routines that they should
+ * quit what they are doing so recovery can run. dlm_recoverd sets
+ * this after recovery is finished.
+ */
+
+#define LSFL_RECOVER_STOP 0
+#define LSFL_RECOVER_DOWN 1
+#define LSFL_RECOVER_LOCK 2
+#define LSFL_RECOVER_WORK 3
+#define LSFL_RUNNING 4
+
+#define LSFL_RCOM_READY 5
+#define LSFL_RCOM_WAIT 6
+#define LSFL_UEVENT_WAIT 7
+#define LSFL_TIMEWARN 8
+#define LSFL_CB_DELAY 9
+#define LSFL_NODIR 10
/* much of this is just saving user space pointers associated with the
lock that we pass back to the user lib with an ast */
@@ -667,7 +693,7 @@
static inline int dlm_recovery_stopped(struct dlm_ls *ls)
{
- return test_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
+ return test_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
}
static inline int dlm_no_directory(struct dlm_ls *ls)
diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 952557d..2e99fb0 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -582,8 +582,6 @@
INIT_LIST_HEAD(&ls->ls_root_list);
init_rwsem(&ls->ls_root_sem);
- down_write(&ls->ls_in_recovery);
-
spin_lock(&lslist_lock);
ls->ls_create_count = 1;
list_add(&ls->ls_list, &lslist);
@@ -597,13 +595,24 @@
}
}
- /* needs to find ls in lslist */
+ init_waitqueue_head(&ls->ls_recover_lock_wait);
+
+ /*
+ * Once started, dlm_recoverd first looks for ls in lslist, then
+ * initializes ls_in_recovery as locked in "down" mode. We need
+ * to wait for the wakeup from dlm_recoverd because in_recovery
+ * has to start out in down mode.
+ */
+
error = dlm_recoverd_start(ls);
if (error) {
log_error(ls, "can't start dlm_recoverd %d", error);
goto out_callback;
}
+ wait_event(ls->ls_recover_lock_wait,
+ test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags));
+
ls->ls_kobj.kset = dlm_kset;
error = kobject_init_and_add(&ls->ls_kobj, &dlm_ktype, NULL,
"%s", ls->ls_name);
diff --git a/fs/dlm/member.c b/fs/dlm/member.c
index 862640a..476557b 100644
--- a/fs/dlm/member.c
+++ b/fs/dlm/member.c
@@ -616,13 +616,13 @@
down_write(&ls->ls_recv_active);
/*
- * Abort any recovery that's in progress (see RECOVERY_STOP,
+ * Abort any recovery that's in progress (see RECOVER_STOP,
* dlm_recovery_stopped()) and tell any other threads running in the
* dlm to quit any processing (see RUNNING, dlm_locking_stopped()).
*/
spin_lock(&ls->ls_recover_lock);
- set_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
+ set_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
new = test_and_clear_bit(LSFL_RUNNING, &ls->ls_flags);
ls->ls_recover_seq++;
spin_unlock(&ls->ls_recover_lock);
@@ -642,12 +642,16 @@
* when recovery is complete.
*/
- if (new)
- down_write(&ls->ls_in_recovery);
+ if (new) {
+ set_bit(LSFL_RECOVER_DOWN, &ls->ls_flags);
+ wake_up_process(ls->ls_recoverd_task);
+ wait_event(ls->ls_recover_lock_wait,
+ test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags));
+ }
/*
* The recoverd suspend/resume makes sure that dlm_recoverd (if
- * running) has noticed RECOVERY_STOP above and quit processing the
+ * running) has noticed RECOVER_STOP above and quit processing the
* previous recovery.
*/
@@ -709,7 +713,8 @@
kfree(rv_old);
}
- dlm_recoverd_kick(ls);
+ set_bit(LSFL_RECOVER_WORK, &ls->ls_flags);
+ wake_up_process(ls->ls_recoverd_task);
return 0;
fail:
diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c
index 87f1a56..9d61947 100644
--- a/fs/dlm/rcom.c
+++ b/fs/dlm/rcom.c
@@ -581,7 +581,7 @@
spin_lock(&ls->ls_recover_lock);
status = ls->ls_recover_status;
- stop = test_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
+ stop = test_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
seq = ls->ls_recover_seq;
spin_unlock(&ls->ls_recover_lock);
diff --git a/fs/dlm/recoverd.c b/fs/dlm/recoverd.c
index 88ce65f..32f9f89 100644
--- a/fs/dlm/recoverd.c
+++ b/fs/dlm/recoverd.c
@@ -41,6 +41,7 @@
set_bit(LSFL_RUNNING, &ls->ls_flags);
/* unblocks processes waiting to enter the dlm */
up_write(&ls->ls_in_recovery);
+ clear_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
error = 0;
}
spin_unlock(&ls->ls_recover_lock);
@@ -262,7 +263,7 @@
rv = ls->ls_recover_args;
ls->ls_recover_args = NULL;
if (rv && ls->ls_recover_seq == rv->seq)
- clear_bit(LSFL_RECOVERY_STOP, &ls->ls_flags);
+ clear_bit(LSFL_RECOVER_STOP, &ls->ls_flags);
spin_unlock(&ls->ls_recover_lock);
if (rv) {
@@ -282,26 +283,34 @@
return -1;
}
+ down_write(&ls->ls_in_recovery);
+ set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
+ wake_up(&ls->ls_recover_lock_wait);
+
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
- if (!test_bit(LSFL_WORK, &ls->ls_flags))
+ if (!test_bit(LSFL_RECOVER_WORK, &ls->ls_flags) &&
+ !test_bit(LSFL_RECOVER_DOWN, &ls->ls_flags))
schedule();
set_current_state(TASK_RUNNING);
- if (test_and_clear_bit(LSFL_WORK, &ls->ls_flags))
+ if (test_and_clear_bit(LSFL_RECOVER_DOWN, &ls->ls_flags)) {
+ down_write(&ls->ls_in_recovery);
+ set_bit(LSFL_RECOVER_LOCK, &ls->ls_flags);
+ wake_up(&ls->ls_recover_lock_wait);
+ }
+
+ if (test_and_clear_bit(LSFL_RECOVER_WORK, &ls->ls_flags))
do_ls_recovery(ls);
}
+ if (test_bit(LSFL_RECOVER_LOCK, &ls->ls_flags))
+ up_write(&ls->ls_in_recovery);
+
dlm_put_lockspace(ls);
return 0;
}
-void dlm_recoverd_kick(struct dlm_ls *ls)
-{
- set_bit(LSFL_WORK, &ls->ls_flags);
- wake_up_process(ls->ls_recoverd_task);
-}
-
int dlm_recoverd_start(struct dlm_ls *ls)
{
struct task_struct *p;
diff --git a/fs/dlm/recoverd.h b/fs/dlm/recoverd.h
index 866657c..8856079 100644
--- a/fs/dlm/recoverd.h
+++ b/fs/dlm/recoverd.h
@@ -14,7 +14,6 @@
#ifndef __RECOVERD_DOT_H__
#define __RECOVERD_DOT_H__
-void dlm_recoverd_kick(struct dlm_ls *ls);
void dlm_recoverd_stop(struct dlm_ls *ls);
int dlm_recoverd_start(struct dlm_ls *ls);
void dlm_recoverd_suspend(struct dlm_ls *ls);