* [PATCH 1/3] cfq-iosched: Fix a memory leak of per cpu stats for root group
2011-05-21 0:02 [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
@ 2011-05-21 0:02 ` Vivek Goyal
2011-05-21 0:02 ` [PATCH 2/3] cfq-iosched: Make IO merge related stats per cpu Vivek Goyal
` (3 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Vivek Goyal @ 2011-05-21 0:02 UTC (permalink / raw)
To: linux-kernel, axboe; +Cc: dpshah, namhyung, vgoyal
We allocated per cpu stats struct for root group but did not free it.
Fix it.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
block/cfq-iosched.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index d646b27..0316f6e 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -3940,6 +3940,11 @@ static void cfq_exit_queue(struct elevator_queue *e)
*/
if (wait)
synchronize_rcu();
+
+#ifdef CONFIG_CFQ_GROUP_IOSCHED
+ /* Free up per cpu stats for root group */
+ free_percpu(cfqd->root_group.blkg.stats_cpu);
+#endif
kfree(cfqd);
}
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH 2/3] cfq-iosched: Make IO merge related stats per cpu
2011-05-21 0:02 [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
2011-05-21 0:02 ` [PATCH 1/3] cfq-iosched: Fix a memory leak of per cpu stats for root group Vivek Goyal
@ 2011-05-21 0:02 ` Vivek Goyal
2011-05-21 0:02 ` [PATCH 3/3] block: call elv_bio_merged() when merged Vivek Goyal
` (2 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Vivek Goyal @ 2011-05-21 0:02 UTC (permalink / raw)
To: linux-kernel, axboe; +Cc: dpshah, namhyung, vgoyal
Make BLKIO_STAT_MERGED per cpu hence gettring rid of need of taking
blkg->stats_lock.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
---
block/blk-cgroup.c | 22 +++++++++++++++++-----
block/blk-cgroup.h | 4 ++--
2 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index e41cc6f..07371cf 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -441,15 +441,27 @@ void blkiocg_update_completion_stats(struct blkio_group *blkg,
}
EXPORT_SYMBOL_GPL(blkiocg_update_completion_stats);
+/* Merged stats are per cpu. */
void blkiocg_update_io_merged_stats(struct blkio_group *blkg, bool direction,
bool sync)
{
+ struct blkio_group_stats_cpu *stats_cpu;
unsigned long flags;
- spin_lock_irqsave(&blkg->stats_lock, flags);
- blkio_add_stat(blkg->stats.stat_arr[BLKIO_STAT_MERGED], 1, direction,
- sync);
- spin_unlock_irqrestore(&blkg->stats_lock, flags);
+ /*
+ * Disabling interrupts to provide mutual exclusion between two
+ * writes on same cpu. It probably is not needed for 64bit. Not
+ * optimizing that case yet.
+ */
+ local_irq_save(flags);
+
+ stats_cpu = this_cpu_ptr(blkg->stats_cpu);
+
+ u64_stats_update_begin(&stats_cpu->syncp);
+ blkio_add_stat(stats_cpu->stat_arr_cpu[BLKIO_STAT_CPU_MERGED], 1,
+ direction, sync);
+ u64_stats_update_end(&stats_cpu->syncp);
+ local_irq_restore(flags);
}
EXPORT_SYMBOL_GPL(blkiocg_update_io_merged_stats);
@@ -1244,7 +1256,7 @@ static int blkiocg_file_read_map(struct cgroup *cgrp, struct cftype *cft,
BLKIO_STAT_WAIT_TIME, 1, 0);
case BLKIO_PROP_io_merged:
return blkio_read_blkg_stats(blkcg, cft, cb,
- BLKIO_STAT_MERGED, 1, 0);
+ BLKIO_STAT_CPU_MERGED, 1, 1);
case BLKIO_PROP_io_queued:
return blkio_read_blkg_stats(blkcg, cft, cb,
BLKIO_STAT_QUEUED, 1, 0);
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 2622267..a71d290 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -39,8 +39,6 @@ enum stat_type {
BLKIO_STAT_SERVICE_TIME = 0,
/* Total time spent waiting in scheduler queue in ns */
BLKIO_STAT_WAIT_TIME,
- /* Number of IOs merged */
- BLKIO_STAT_MERGED,
/* Number of IOs queued up */
BLKIO_STAT_QUEUED,
/* All the single valued stats go below this */
@@ -63,6 +61,8 @@ enum stat_type_cpu {
BLKIO_STAT_CPU_SERVICE_BYTES,
/* Total IOs serviced, post merge */
BLKIO_STAT_CPU_SERVICED,
+ /* Number of IOs merged */
+ BLKIO_STAT_CPU_MERGED,
BLKIO_STAT_CPU_NR
};
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH 3/3] block: call elv_bio_merged() when merged
2011-05-21 0:02 [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
2011-05-21 0:02 ` [PATCH 1/3] cfq-iosched: Fix a memory leak of per cpu stats for root group Vivek Goyal
2011-05-21 0:02 ` [PATCH 2/3] cfq-iosched: Make IO merge related stats per cpu Vivek Goyal
@ 2011-05-21 0:02 ` Vivek Goyal
2011-05-21 0:06 ` [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
2011-05-23 8:03 ` Jens Axboe
4 siblings, 0 replies; 9+ messages in thread
From: Vivek Goyal @ 2011-05-21 0:02 UTC (permalink / raw)
To: linux-kernel, axboe; +Cc: dpshah, namhyung, vgoyal
Commit 73c101011926 ("block: initial patch for on-stack per-task plugging")
removed calls to elv_bio_merged() when @bio merged with @req. Re-add them.
This in turn will update merged stats in associated group. That
should be safe as long as request has got reference to the blkio_group.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Divyesh Shah <dpshah@google.com>
---
block/blk-core.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 7369eee..c8303e9 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1122,6 +1122,7 @@ static bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
req->ioprio = ioprio_best(req->ioprio, bio_prio(bio));
drive_stat_acct(req, 0);
+ elv_bio_merged(q, req, bio);
return true;
}
@@ -1155,6 +1156,7 @@ static bool bio_attempt_front_merge(struct request_queue *q,
req->ioprio = ioprio_best(req->ioprio, bio_prio(bio));
drive_stat_acct(req, 0);
+ elv_bio_merged(q, req, bio);
return true;
}
--
1.7.4.4
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH 0/3] block: Per cpu merge stats and cfq fix
2011-05-21 0:02 [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
` (2 preceding siblings ...)
2011-05-21 0:02 ` [PATCH 3/3] block: call elv_bio_merged() when merged Vivek Goyal
@ 2011-05-21 0:06 ` Vivek Goyal
2011-05-23 8:04 ` Jens Axboe
2011-05-23 11:07 ` Namhyung Kim
2011-05-23 8:03 ` Jens Axboe
4 siblings, 2 replies; 9+ messages in thread
From: Vivek Goyal @ 2011-05-21 0:06 UTC (permalink / raw)
To: linux-kernel, axboe; +Cc: dpshah, namhyung
On Fri, May 20, 2011 at 08:02:44PM -0400, Vivek Goyal wrote:
> Hi Jens,
>
> Here is the patch for making merge stats per cpu. While scanning the code
> I also noticed that in one case I was not freeing up per cpu stats. First
> patch fixes it. I also included Namhyung Kim's bio merge fix.
>
> Thanks
> Vivek
>
> Vivek Goyal (3):
> cfq-iosched: Fix a memory leak of per cpu stats for root group
> cfq-iosched: Make IO merge related stats per cpu
Minor correction. Following patch author is Namhyung Kim.
Namhyung Kim(1)
> block: call elv_bio_merged() when merged
Thanks
Vivek
>
> block/blk-cgroup.c | 22 +++++++++++++++++-----
> block/blk-cgroup.h | 4 ++--
> block/blk-core.c | 2 ++
> block/cfq-iosched.c | 5 +++++
> 4 files changed, 26 insertions(+), 7 deletions(-)
>
> --
> 1.7.4.4
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH 0/3] block: Per cpu merge stats and cfq fix
2011-05-21 0:06 ` [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
@ 2011-05-23 8:04 ` Jens Axboe
2011-05-23 13:53 ` Namhyung Kim
2011-05-23 11:07 ` Namhyung Kim
1 sibling, 1 reply; 9+ messages in thread
From: Jens Axboe @ 2011-05-23 8:04 UTC (permalink / raw)
To: Vivek Goyal; +Cc: linux-kernel, dpshah, namhyung
On 2011-05-21 02:06, Vivek Goyal wrote:
> On Fri, May 20, 2011 at 08:02:44PM -0400, Vivek Goyal wrote:
>> Hi Jens,
>>
>> Here is the patch for making merge stats per cpu. While scanning the code
>> I also noticed that in one case I was not freeing up per cpu stats. First
>> patch fixes it. I also included Namhyung Kim's bio merge fix.
>>
>> Thanks
>> Vivek
>>
>> Vivek Goyal (3):
>> cfq-iosched: Fix a memory leak of per cpu stats for root group
>> cfq-iosched: Make IO merge related stats per cpu
>
> Minor correction. Following patch author is Namhyung Kim.
>
> Namhyung Kim(1)
Ugh, already merged it. I should have noticed that too, sorry about that
Namhyung.
--
Jens Axboe
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 0/3] block: Per cpu merge stats and cfq fix
2011-05-23 8:04 ` Jens Axboe
@ 2011-05-23 13:53 ` Namhyung Kim
0 siblings, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2011-05-23 13:53 UTC (permalink / raw)
To: Jens Axboe; +Cc: Vivek Goyal, linux-kernel, dpshah
2011-05-23 (월), 10:04 +0200, Jens Axboe:
> On 2011-05-21 02:06, Vivek Goyal wrote:
> > On Fri, May 20, 2011 at 08:02:44PM -0400, Vivek Goyal wrote:
> >> Hi Jens,
> >>
> >> Here is the patch for making merge stats per cpu. While scanning the code
> >> I also noticed that in one case I was not freeing up per cpu stats. First
> >> patch fixes it. I also included Namhyung Kim's bio merge fix.
> >>
> >> Thanks
> >> Vivek
> >>
> >> Vivek Goyal (3):
> >> cfq-iosched: Fix a memory leak of per cpu stats for root group
> >> cfq-iosched: Make IO merge related stats per cpu
> >
> > Minor correction. Following patch author is Namhyung Kim.
> >
> > Namhyung Kim(1)
>
> Ugh, already merged it. I should have noticed that too, sorry about that
> Namhyung.
>
Hi, Jens.
It's all right, I'm fine :)
--
Regards,
Namhyung Kim
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 0/3] block: Per cpu merge stats and cfq fix
2011-05-21 0:06 ` [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
2011-05-23 8:04 ` Jens Axboe
@ 2011-05-23 11:07 ` Namhyung Kim
1 sibling, 0 replies; 9+ messages in thread
From: Namhyung Kim @ 2011-05-23 11:07 UTC (permalink / raw)
To: Vivek Goyal; +Cc: linux-kernel, axboe, dpshah
2011-05-20 (금), 20:06 -0400, Vivek Goyal:
> On Fri, May 20, 2011 at 08:02:44PM -0400, Vivek Goyal wrote:
> > Hi Jens,
> >
> > Here is the patch for making merge stats per cpu. While scanning the code
> > I also noticed that in one case I was not freeing up per cpu stats. First
> > patch fixes it. I also included Namhyung Kim's bio merge fix.
> >
> > Thanks
> > Vivek
> >
> > Vivek Goyal (3):
> > cfq-iosched: Fix a memory leak of per cpu stats for root group
> > cfq-iosched: Make IO merge related stats per cpu
>
> Minor correction. Following patch author is Namhyung Kim.
>
> Namhyung Kim(1)
>
> > block: call elv_bio_merged() when merged
>
> Thanks
> Vivek
>
Hi, Vivek. Thanks a lot for your work. :)
--
Regards,
Namhyung Kim
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 0/3] block: Per cpu merge stats and cfq fix
2011-05-21 0:02 [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
` (3 preceding siblings ...)
2011-05-21 0:06 ` [PATCH 0/3] block: Per cpu merge stats and cfq fix Vivek Goyal
@ 2011-05-23 8:03 ` Jens Axboe
4 siblings, 0 replies; 9+ messages in thread
From: Jens Axboe @ 2011-05-23 8:03 UTC (permalink / raw)
To: Vivek Goyal; +Cc: linux-kernel, dpshah, namhyung
On 2011-05-21 02:02, Vivek Goyal wrote:
> Hi Jens,
>
> Here is the patch for making merge stats per cpu. While scanning the code
> I also noticed that in one case I was not freeing up per cpu stats. First
> patch fixes it. I also included Namhyung Kim's bio merge fix.
Thanks, looks fine. Merged.
--
Jens Axboe
^ permalink raw reply [flat|nested] 9+ messages in thread