From: Lei Wen <adrian.wenl@gmail.com>
To: Alex Shi <seakeel@gmail.com>
Cc: "Paul Turner" <pjt@google.com>, "Ingo Molnar" <mingo@redhat.com>,
"Peter Zijlstra" <peterz@infradead.org>,
"Thomas Gleixner" <tglx@linutronix.de>,
"Andrew Morton" <akpm@linux-foundation.org>,
"Borislav Petkov" <bp@alien8.de>,
"Namhyung Kim" <namhyung@kernel.org>,
"Mike Galbraith" <efault@gmx.de>,
"Morten Rasmussen" <morten.rasmussen@arm.com>,
"Vincent Guittot" <vincent.guittot@linaro.org>,
"Preeti U Murthy" <preeti@linux.vnet.ibm.com>,
"Viresh Kumar" <viresh.kumar@linaro.org>,
LKML <linux-kernel@vger.kernel.org>,
"Mel Gorman" <mgorman@suse.de>, "Rik van Riel" <riel@redhat.com>,
"Michael Wang" <wangyun@linux.vnet.ibm.com>,
"Jason Low" <jason.low2@hp.com>,
"Changlong Xie" <changlongx.xie@intel.com>,
sgruszka@redhat.com, "Frédéric Weisbecker" <fweisbec@gmail.com>
Subject: Re: [patch v8 4/9] sched: fix slept time double counting in enqueue entity
Date: Fri, 21 Jun 2013 10:50:32 +0800 [thread overview]
Message-ID: <CALZhoSR8pLfqO+XfEfHB3-UuV5_xu=AV2mCf2BQgaaQoWd-tbw@mail.gmail.com> (raw)
In-Reply-To: <51C3BCE1.1080405@gmail.com>
Alex,
On Fri, Jun 21, 2013 at 10:39 AM, Alex Shi <seakeel@gmail.com> wrote:
> On 06/21/2013 10:30 AM, Lei Wen wrote:
>> Hi Alex,
>>
>> On Thu, Jun 20, 2013 at 10:59 PM, Alex Shi <seakeel@gmail.com> wrote:
>>> On 06/20/2013 10:46 AM, Lei Wen wrote:
>>>>
>>>>
>>>> But here I have a question, there is another usage of __synchronzie_entity_decay
>>>> in current kernel, in the switched_from_fair function.
>>>>
>>>> If task being frequently switched between rt and fair class, would it
>>>> also bring the
>>>> redundant issue? Do we need patch like below?
>>>>
>>>> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
>>>> index b5408e1..9640c66 100644
>>>> --- a/kernel/sched/fair.c
>>>> +++ b/kernel/sched/fair.c
>>>> @@ -5856,7 +5856,7 @@ static void switched_from_fair(struct rq *rq,
>>>> struct task_struct *p)
>>>> */
>>>> if (p->se.avg.decay_count) {
>>>> struct cfs_rq *cfs_rq = cfs_rq_of(&p->se);
>>>> - se->avg.last_runnable_update +=
>>>> + p->se.avg.last_runnable_update +=
>>>
>>> what tree does this patch base on?
>>
>> I create the patch based on v3.9 kernel.
>> If it is ok, I could create a formal one based on latest kernel.
>
> In the linus tree, the first commit which introduced
> __synchronize_entity_decay(&p->se) here is
> 9ee474f55664ff63111c843099d365e7ecffb56f
> +
> +#if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP)
> + /*
> + * Remove our load from contribution when we leave sched_fair
> + * and ensure we don't carry in an old decay_count if we
> + * switch back.
> + */
> + if (p->se.avg.decay_count) {
> + struct cfs_rq *cfs_rq = cfs_rq_of(&p->se);
> + __synchronize_entity_decay(&p->se);
> + subtract_blocked_load_contrib(cfs_rq,
> + p->se.avg.load_avg_contrib);
> + }
> +#endif
> }
>
> And it is never changed from then on. So your code must based on a
> incorrect kernel. please do a double check.
I see your point... I made the mistake that update the wrong patch...
Please help check this one.
commit 5fc3d5c74f8359ef382d9a20ffe657ffc237c109
Author: Lei Wen <leiwen@marvell.com>
Date: Thu Jun 20 10:43:59 2013 +0800
sched: fix potential twice decay issue
Signed-off-by: Lei Wen <leiwen@marvell.com>
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index c61a614..9640c66 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -5856,7 +5856,8 @@ static void switched_from_fair(struct rq *rq,
struct task_struct *p)
*/
if (p->se.avg.decay_count) {
struct cfs_rq *cfs_rq = cfs_rq_of(&p->se);
- __synchronize_entity_decay(&p->se);
+ p->se.avg.last_runnable_update +=
+ __synchronize_entity_decay(&p->se);
subtract_blocked_load_contrib(cfs_rq,
p->se.avg.load_avg_contrib);
}
Thanks,
Lei
>>
>> Thanks,
>> Lei
>>
>>>> __synchronize_entity_decay(&p->se);
>>>> subtract_blocked_load_contrib(cfs_rq,
>>>> p->se.avg.load_avg_contrib);
>>>
>>>
>>> --
>>> Thanks
>>> Alex
>
>
> --
> Thanks
> Alex
next prev parent reply other threads:[~2013-06-21 2:50 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-07 7:20 [patch 0/9] sched: use runnable load avg in balance Alex Shi
2013-06-07 7:20 ` [patch v8 1/9] Revert "sched: Introduce temporary FAIR_GROUP_SCHED dependency for load-tracking" Alex Shi
2013-06-07 7:20 ` [patch v8 2/9] sched: move few runnable tg variables into CONFIG_SMP Alex Shi
2013-06-17 12:26 ` Paul Turner
2013-06-17 15:32 ` Alex Shi
2013-06-07 7:20 ` [patch v8 3/9] sched: set initial value of runnable avg for new forked task Alex Shi
2013-06-10 1:51 ` Gu Zheng
2013-06-14 10:02 ` Lei Wen
2013-06-14 13:59 ` Alex Shi
2013-06-15 12:09 ` Lei Wen
2013-06-17 0:33 ` Alex Shi
2013-06-20 10:23 ` Morten Rasmussen
2013-06-21 2:57 ` Lei Wen
2013-06-17 9:20 ` Peter Zijlstra
2013-06-17 12:26 ` Lei Wen
2013-06-17 12:33 ` Peter Zijlstra
2013-06-14 11:09 ` Paul Turner
2013-06-14 14:16 ` Alex Shi
2013-06-17 9:21 ` Peter Zijlstra
2013-06-17 9:39 ` Paul Turner
2013-06-17 13:00 ` Peter Zijlstra
2013-06-17 9:57 ` Alex Shi
2013-06-17 13:07 ` Peter Zijlstra
2013-06-17 13:23 ` Alex Shi
2013-06-07 7:20 ` [patch v8 4/9] sched: fix slept time double counting in enqueue entity Alex Shi
2013-06-17 11:51 ` Paul Turner
2013-06-17 15:41 ` Alex Shi
2013-06-20 1:43 ` Lei Wen
2013-06-20 1:46 ` Alex Shi
2013-06-20 2:46 ` Lei Wen
2013-06-20 14:59 ` Alex Shi
2013-06-21 2:30 ` Lei Wen
2013-06-21 2:39 ` Alex Shi
2013-06-21 2:50 ` Lei Wen [this message]
2013-06-21 8:56 ` Alex Shi
2013-06-21 9:18 ` Lei Wen
2013-06-21 11:09 ` Alex Shi
2013-06-21 13:26 ` Lei Wen
2013-06-07 7:20 ` [patch v8 5/9] sched: update cpu load after task_tick Alex Shi
2013-06-17 11:54 ` Paul Turner
2013-06-07 7:20 ` [patch v8 6/9] sched: compute runnable load avg in cpu_load and cpu_avg_load_per_task Alex Shi
2013-06-10 1:49 ` Gu Zheng
2013-06-10 2:01 ` Alex Shi
2013-06-10 2:05 ` Gu Zheng
2013-06-17 10:51 ` Paul Turner
2013-06-17 12:17 ` Paul Turner
2013-06-17 13:39 ` Peter Zijlstra
2013-06-17 13:59 ` Alex Shi
2013-06-17 13:57 ` Alex Shi
2013-06-17 23:00 ` Paul Turner
2013-06-18 3:44 ` Alex Shi
2013-06-18 9:44 ` Alex Shi
2013-06-19 8:15 ` Alex Shi
2013-06-20 0:33 ` Alex Shi
2013-06-17 14:57 ` Alex Shi
2013-06-17 15:21 ` Alex Shi
2013-06-07 7:20 ` [patch v8 7/9] math64: add div64_ul macro Alex Shi
2013-06-07 7:20 ` [patch v8 8/9] sched: consider runnable load average in move_tasks Alex Shi
2013-06-17 10:58 ` Paul Turner
2013-06-17 14:01 ` Alex Shi
2013-06-17 14:15 ` Alex Shi
2013-06-17 13:59 ` Peter Zijlstra
2013-06-17 14:29 ` Alex Shi
2013-06-07 7:20 ` [patch v8 9/9] sched/tg: remove blocked_load_avg in balance Alex Shi
2013-06-17 9:38 ` Peter Zijlstra
2013-06-17 12:20 ` Paul Turner
2013-06-17 14:01 ` Peter Zijlstra
2013-06-19 9:49 ` Alex Shi
2013-06-20 1:33 ` Alex Shi
2013-06-08 2:37 ` [patch 0/9] sched: use runnable load avg " Alex Shi
2013-06-10 1:35 ` Alex Shi
2013-06-10 15:01 ` Peter Zijlstra
2013-06-11 3:30 ` Alex Shi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CALZhoSR8pLfqO+XfEfHB3-UuV5_xu=AV2mCf2BQgaaQoWd-tbw@mail.gmail.com' \
--to=adrian.wenl@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=bp@alien8.de \
--cc=changlongx.xie@intel.com \
--cc=efault@gmx.de \
--cc=fweisbec@gmail.com \
--cc=jason.low2@hp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mingo@redhat.com \
--cc=morten.rasmussen@arm.com \
--cc=namhyung@kernel.org \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=preeti@linux.vnet.ibm.com \
--cc=riel@redhat.com \
--cc=seakeel@gmail.com \
--cc=sgruszka@redhat.com \
--cc=tglx@linutronix.de \
--cc=vincent.guittot@linaro.org \
--cc=viresh.kumar@linaro.org \
--cc=wangyun@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).