From: NeilBrown <neilb@suse.de>
To: NeilBrown <neilb@suse.de>
Cc: Jonathan Brassow <jbrassow@redhat.com>, linux-raid@vger.kernel.org
Subject: Re: [PATCH] MD: Remember the last sync operation that was performed
Date: Wed, 3 Jul 2013 09:45:53 +1000 [thread overview]
Message-ID: <20130703094553.530f21f9@notabene.brown> (raw)
In-Reply-To: <20130626120024.3ab35f02@notabene.brown>
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On Wed, 26 Jun 2013 12:00:24 +1000 NeilBrown <neilb@suse.de> wrote:
> On Tue, 25 Jun 2013 01:23:59 -0500 Jonathan Brassow <jbrassow@redhat.com>
> wrote:
>
> > MD: Remember the last sync operation that was performed
> >
> > This patch adds a field to the mddev structure to track the last
> > sync operation that was performed. This is especially useful when
> > it comes to what is recorded in mismatch_cnt in sysfs. If the
> > last operation was "data-check", then it reports the number of
> > descrepancies found by the user-initiated check. If it was a
> > "repair" operation, then it is reporting the number of
> > descrepancies repaired. etc.
> >
> > Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
> >
> > Index: linux-upstream/drivers/md/dm-raid.c
> > ===================================================================
> > --- linux-upstream.orig/drivers/md/dm-raid.c
> > +++ linux-upstream/drivers/md/dm-raid.c
> > @@ -1388,6 +1388,7 @@ static void raid_status(struct dm_target
> > * performing a "check" of the array.
> > */
> > DMEMIT(" %llu",
> > + (strcmp(rs->md.last_sync_action, "data-check")) ? 0 :
> > (unsigned long long)
> > atomic64_read(&rs->md.resync_mismatches));
> > break;
> > @@ -1651,7 +1652,7 @@ static void raid_resume(struct dm_target
> >
> > static struct target_type raid_target = {
> > .name = "raid",
> > - .version = {1, 5, 1},
> > + .version = {1, 5, 2},
> > .module = THIS_MODULE,
> > .ctr = raid_ctr,
> > .dtr = raid_dtr,
> > Index: linux-upstream/drivers/md/md.c
> > ===================================================================
> > --- linux-upstream.orig/drivers/md/md.c
> > +++ linux-upstream/drivers/md/md.c
> > @@ -521,6 +521,7 @@ void mddev_init(struct mddev *mddev)
> > init_waitqueue_head(&mddev->recovery_wait);
> > mddev->reshape_position = MaxSector;
> > mddev->reshape_backwards = 0;
> > + mddev->last_sync_action = "none";
> > mddev->resync_min = 0;
> > mddev->resync_max = MaxSector;
> > mddev->level = LEVEL_NONE;
> > @@ -4272,6 +4273,17 @@ action_store(struct mddev *mddev, const
> > return len;
> > }
> >
> > +static struct md_sysfs_entry md_scan_mode =
> > +__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
> > +
> > +static ssize_t
> > +last_sync_action_show(struct mddev *mddev, char *page)
> > +{
> > + return sprintf(page, "%s\n", mddev->last_sync_action);
> > +}
> > +
> > +static struct md_sysfs_entry md_last_scan_mode = __ATTR_RO(last_sync_action);
> > +
> > static ssize_t
> > mismatch_cnt_show(struct mddev *mddev, char *page)
> > {
> > @@ -4280,10 +4292,6 @@ mismatch_cnt_show(struct mddev *mddev, c
> > atomic64_read(&mddev->resync_mismatches));
> > }
> >
> > -static struct md_sysfs_entry md_scan_mode =
> > -__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
> > -
> > -
> > static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
> >
> > static ssize_t
> > @@ -4686,6 +4694,7 @@ static struct attribute *md_default_attr
> >
> > static struct attribute *md_redundancy_attrs[] = {
> > &md_scan_mode.attr,
> > + &md_last_scan_mode.attr,
> > &md_mismatches.attr,
> > &md_sync_min.attr,
> > &md_sync_max.attr,
> > @@ -7336,7 +7345,7 @@ void md_do_sync(struct md_thread *thread
> > if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
> > desc = "data-check";
> > else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
> > - desc = "requested-resync";
> > + desc = "requested-resync"; /* AKA "repair" */
> > else
> > desc = "resync";
> > } else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
> > @@ -7344,6 +7353,8 @@ void md_do_sync(struct md_thread *thread
> > else
> > desc = "recovery";
> >
> > + mddev->last_sync_action = desc;
> > +
> > /* we overload curr_resync somewhat here.
> > * 0 == not engaged in resync at all
> > * 2 == checking that there is no conflict with another sync
> > Index: linux-upstream/drivers/md/md.h
> > ===================================================================
> > --- linux-upstream.orig/drivers/md/md.h
> > +++ linux-upstream/drivers/md/md.h
> > @@ -268,6 +268,14 @@ struct mddev {
> >
> > struct md_thread *thread; /* management thread */
> > struct md_thread *sync_thread; /* doing resync or reconstruct */
> > +
> > + /* 'last_sync_action' is initialized to "none". It is set when a
> > + * sync operation (i.e "data-check", "requested-resync", "resync",
> > + * "recovery", or "reshape") is started. It holds this value even
> > + * when the sync thread is "frozen" (interrupted) or "idle" (stopped
> > + * or finished). It is overwritten when a new sync operation is begun.
> > + */
> > + char *last_sync_action;
> > sector_t curr_resync; /* last block scheduled */
> > /* As resync requests can complete out of order, we cannot easily track
> > * how much resync has been completed. So we occasionally pause until
> > Index: linux-upstream/Documentation/device-mapper/dm-raid.txt
> > ===================================================================
> > --- linux-upstream.orig/Documentation/device-mapper/dm-raid.txt
> > +++ linux-upstream/Documentation/device-mapper/dm-raid.txt
> > @@ -223,3 +223,4 @@ Version History
> > 1.5.0 Add message interface to allow manipulation of the sync_action.
> > New status (STATUSTYPE_INFO) fields: sync_action and mismatch_cnt.
> > 1.5.1 Add ability to restore transiently failed devices on resume.
> > +1.5.2 'mismatch_cnt' is zero unless [last_]sync_action is "check".
> >
> >
>
> Looks sane. Applied, thanks.
Actually, I thought better of one little part of this.
The words "data-check" and "requested-resync" only appear in 'dmesg', not in
/sys or /proc and I want it to stay that way.
Also it is important that the new "last_sync_action" has the same set of
words as "sync_action".
So I made that change. The new patch is below and in my for-next, and will
go to Linus tomorrow.
NeilBrown
From c4a39551451666229b4ea5e8aae8ca0131d00665 Mon Sep 17 00:00:00 2001
From: Jonathan Brassow <jbrassow@redhat.com>
Date: Tue, 25 Jun 2013 01:23:59 -0500
Subject: [PATCH] MD: Remember the last sync operation that was performed
MD: Remember the last sync operation that was performed
This patch adds a field to the mddev structure to track the last
sync operation that was performed. This is especially useful when
it comes to what is recorded in mismatch_cnt in sysfs. If the
last operation was "data-check", then it reports the number of
descrepancies found by the user-initiated check. If it was a
"repair" operation, then it is reporting the number of
descrepancies repaired. etc.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/Documentation/device-mapper/dm-raid.txt b/Documentation/device-mapper/dm-raid.txt
index 2bb3a68..ef8ba9f 100644
--- a/Documentation/device-mapper/dm-raid.txt
+++ b/Documentation/device-mapper/dm-raid.txt
@@ -223,3 +223,4 @@ Version History
1.5.0 Add message interface to allow manipulation of the sync_action.
New status (STATUSTYPE_INFO) fields: sync_action and mismatch_cnt.
1.5.1 Add ability to restore transiently failed devices on resume.
+1.5.2 'mismatch_cnt' is zero unless [last_]sync_action is "check".
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 21e8e46..4880b69 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -1388,6 +1388,7 @@ static void raid_status(struct dm_target *ti, status_type_t type,
* performing a "check" of the array.
*/
DMEMIT(" %llu",
+ (strcmp(rs->md.last_sync_action, "check")) ? 0 :
(unsigned long long)
atomic64_read(&rs->md.resync_mismatches));
break;
@@ -1651,7 +1652,7 @@ static void raid_resume(struct dm_target *ti)
static struct target_type raid_target = {
.name = "raid",
- .version = {1, 5, 1},
+ .version = {1, 5, 2},
.module = THIS_MODULE,
.ctr = raid_ctr,
.dtr = raid_dtr,
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 26f9452..dddc87b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -521,6 +521,7 @@ void mddev_init(struct mddev *mddev)
init_waitqueue_head(&mddev->recovery_wait);
mddev->reshape_position = MaxSector;
mddev->reshape_backwards = 0;
+ mddev->last_sync_action = "none";
mddev->resync_min = 0;
mddev->resync_max = MaxSector;
mddev->level = LEVEL_NONE;
@@ -4272,6 +4273,17 @@ action_store(struct mddev *mddev, const char *page, size_t len)
return len;
}
+static struct md_sysfs_entry md_scan_mode =
+__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
+
+static ssize_t
+last_sync_action_show(struct mddev *mddev, char *page)
+{
+ return sprintf(page, "%s\n", mddev->last_sync_action);
+}
+
+static struct md_sysfs_entry md_last_scan_mode = __ATTR_RO(last_sync_action);
+
static ssize_t
mismatch_cnt_show(struct mddev *mddev, char *page)
{
@@ -4280,10 +4292,6 @@ mismatch_cnt_show(struct mddev *mddev, char *page)
atomic64_read(&mddev->resync_mismatches));
}
-static struct md_sysfs_entry md_scan_mode =
-__ATTR(sync_action, S_IRUGO|S_IWUSR, action_show, action_store);
-
-
static struct md_sysfs_entry md_mismatches = __ATTR_RO(mismatch_cnt);
static ssize_t
@@ -4686,6 +4694,7 @@ static struct attribute *md_default_attrs[] = {
static struct attribute *md_redundancy_attrs[] = {
&md_scan_mode.attr,
+ &md_last_scan_mode.attr,
&md_mismatches.attr,
&md_sync_min.attr,
&md_sync_max.attr,
@@ -7329,7 +7338,7 @@ void md_do_sync(struct md_thread *thread)
sector_t last_check;
int skipped = 0;
struct md_rdev *rdev;
- char *desc;
+ char *desc, *action = NULL;
struct blk_plug plug;
/* just incase thread restarts... */
@@ -7339,17 +7348,21 @@ void md_do_sync(struct md_thread *thread)
return;
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
- if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
+ if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
desc = "data-check";
- else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
+ action = "check";
+ } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
desc = "requested-resync";
- else
+ action = "repair";
+ } else
desc = "resync";
} else if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
desc = "reshape";
else
desc = "recovery";
+ mddev->last_sync_action = action ?: desc;
+
/* we overload curr_resync somewhat here.
* 0 == not engaged in resync at all
* 2 == checking that there is no conflict with another sync
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 653f992b6..20f02c0 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -268,6 +268,14 @@ struct mddev {
struct md_thread *thread; /* management thread */
struct md_thread *sync_thread; /* doing resync or reconstruct */
+
+ /* 'last_sync_action' is initialized to "none". It is set when a
+ * sync operation (i.e "data-check", "requested-resync", "resync",
+ * "recovery", or "reshape") is started. It holds this value even
+ * when the sync thread is "frozen" (interrupted) or "idle" (stopped
+ * or finished). It is overwritten when a new sync operation is begun.
+ */
+ char *last_sync_action;
sector_t curr_resync; /* last block scheduled */
/* As resync requests can complete out of order, we cannot easily track
* how much resync has been completed. So we occasionally pause until
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prev parent reply other threads:[~2013-07-02 23:45 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-25 6:23 [PATCH] MD: Remember the last sync operation that was performed Jonathan Brassow
2013-06-26 2:00 ` NeilBrown
2013-07-02 23:45 ` NeilBrown [this message]
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