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Make sure all changes to md/sync_action are notified.

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When the 'resync' thread starts or stops, when we explicitly
set sync_action, or when we determine that there is definitely nothing
to do, we notify sync_action.

To stop "sync_action" from occasionally showing the wrong value,
we introduce a new flags - MD_RECOVERY_RECOVER - to say that a
recovery is probably needed or happening, and we make sure
that we set MD_RECOVERY_RUNNING before clearing MD_RECOVERY_NEEDED.

Signed-off-by: Neil Brown <neilb@suse.de>
This commit is contained in:
Neil Brown 2008-06-28 08:31:41 +10:00
parent 0fd62b861e
commit 72a23c211e
3 changed files with 36 additions and 6 deletions
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6
Documentation/md.txt
View File

@ -386,6 +386,12 @@ also have
'check' and 'repair' will start the appropriate process
providing the current state is 'idle'.
This file responds to select/poll. Any important change in the value
triggers a poll event. Sometimes the value will briefly be
"recover" if a recovery seems to be needed, but cannot be
achieved. In that case, the transition to "recover" isn't
notified, but the transition away is.
mismatch_count
When performing 'check' and 'repair', and possibly when
performing 'resync', md will count the number of errors that are

34
drivers/md/md.c
View File

@ -169,7 +169,6 @@ void md_new_event(mddev_t *mddev)
{
atomic_inc(&md_event_count);
wake_up(&md_event_waiters);
sysfs_notify(&mddev->kobj, NULL, "sync_action");
}
EXPORT_SYMBOL_GPL(md_new_event);
@ -2936,7 +2935,7 @@ action_show(mddev_t *mddev, char *page)
type = "check";
else
type = "repair";
} else
} else if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery))
type = "recover";
}
return sprintf(page, "%s\n", type);
@ -2958,9 +2957,12 @@ action_store(mddev_t *mddev, const char *page, size_t len)
} else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) ||
test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))
return -EBUSY;
else if (cmd_match(page, "resync") || cmd_match(page, "recover"))
else if (cmd_match(page, "resync"))
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
else if (cmd_match(page, "reshape")) {
else if (cmd_match(page, "recover")) {
set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
} else if (cmd_match(page, "reshape")) {
int err;
if (mddev->pers->start_reshape == NULL)
return -EINVAL;
@ -2977,6 +2979,7 @@ action_store(mddev_t *mddev, const char *page, size_t len)
}
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
sysfs_notify(&mddev->kobj, NULL, "sync_action");
return len;
}
@ -3682,6 +3685,7 @@ static int do_md_run(mddev_t * mddev)
mddev->changed = 1;
md_new_event(mddev);
sysfs_notify(&mddev->kobj, NULL, "array_state");
sysfs_notify(&mddev->kobj, NULL, "sync_action");
kobject_uevent(&mddev->gendisk->dev.kobj, KOBJ_CHANGE);
return 0;
}
@ -4252,6 +4256,8 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
export_rdev(rdev);
md_update_sb(mddev, 1);
if (mddev->degraded)
set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
return err;
@ -5105,6 +5111,8 @@ void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
if (!mddev->pers->error_handler)
return;
mddev->pers->error_handler(mddev,rdev);
if (mddev->degraded)
set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
md_wakeup_thread(mddev->thread);
@ -6055,13 +6063,18 @@ void md_check_recovery(mddev_t *mddev)
mddev->recovery = 0;
/* flag recovery needed just to double check */
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
sysfs_notify(&mddev->kobj, NULL, "sync_action");
md_new_event(mddev);
goto unlock;
}
/* Set RUNNING before clearing NEEDED to avoid
* any transients in the value of "sync_action".
*/
set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
/* Clear some bits that don't mean anything, but
* might be left set
*/
clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
clear_bit(MD_RECOVERY_INTR, &mddev->recovery);
clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
@ -6079,17 +6092,19 @@ void md_check_recovery(mddev_t *mddev)
/* Cannot proceed */
goto unlock;
set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
} else if ((spares = remove_and_add_spares(mddev))) {
clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
} else if (mddev->recovery_cp < MaxSector) {
set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
clear_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
} else if (!test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
/* nothing to be done ... */
goto unlock;
if (mddev->pers->sync_request) {
set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
if (spares && mddev->bitmap && ! mddev->bitmap->file) {
/* We are adding a device or devices to an array
* which has the bitmap stored on all devices.
@ -6108,9 +6123,16 @@ void md_check_recovery(mddev_t *mddev)
mddev->recovery = 0;
} else
md_wakeup_thread(mddev->sync_thread);
sysfs_notify(&mddev->kobj, NULL, "sync_action");
md_new_event(mddev);
}
unlock:
if (!mddev->sync_thread) {
clear_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
if (test_and_clear_bit(MD_RECOVERY_RECOVER,
&mddev->recovery))
sysfs_notify(&mddev->kobj, NULL, "sync_action");
}
mddev_unlock(mddev);
}
}

2
include/linux/raid/md_k.h
View File

@ -188,6 +188,7 @@ struct mddev_s
* NEEDED: we might need to start a resync/recover
* RUNNING: a thread is running, or about to be started
* SYNC: actually doing a resync, not a recovery
* RECOVER: doing recovery, or need to try it.
* INTR: resync needs to be aborted for some reason
* DONE: thread is done and is waiting to be reaped
* REQUEST: user-space has requested a sync (used with SYNC)
@ -198,6 +199,7 @@ struct mddev_s
*/
#define MD_RECOVERY_RUNNING 0
#define MD_RECOVERY_SYNC 1
#define MD_RECOVERY_RECOVER 2
#define MD_RECOVERY_INTR 3
#define MD_RECOVERY_DONE 4
#define MD_RECOVERY_NEEDED 5