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Subject: Re: [PATCH] sched/core: add __sched tag for io_schedule()
To:     Tejun Heo <tj@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
CC:     Ingo Molnar <mingo@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        "Peter Zijlstra" <peterz@infradead.org>, <stable@vger.kernel.org>,
        Miao Xie <miaoxie@huawei.com>, <koujilong@huawei.com>
References: <20190531082912.80724-1-gaoxiang25@huawei.com>
 <20190531143759.GD374014@devbig004.ftw2.facebook.com>
From:   Gao Xiang <gaoxiang25@huawei.com>
Message-ID: <b95526a4-33cc-12df-020c-011d67ca797b@huawei.com>
Date:   Mon, 3 Jun 2019 12:25:02 +0800
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On 2019/5/31 22:37, Tejun Heo wrote:
> On Fri, May 31, 2019 at 04:29:12PM +0800, Gao Xiang wrote:
>> non-inline io_schedule() was introduced in
>> commit 10ab56434f2f ("sched/core: Separate out io_schedule_prepare() and io_schedule_finish()")
>> Keep in line with io_schedule_timeout, Otherwise
>> "/proc/<pid>/wchan" will report io_schedule()
>> rather than its callers when waiting io.
>>
>> Reported-by: Jilong Kou <koujilong@huawei.com>
>> Cc: Tejun Heo <tj@kernel.org>
>> Cc: Ingo Molnar <mingo@redhat.com>
>> Cc: Peter Zijlstra <peterz@infradead.org>
>> Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
> 
> Acked-by: Tejun Heo <tj@kernel.org>

Cc: <stable@vger.kernel.org> # 4.11+

Thanks Tejun. This patch will be needed for io performance analysis
since we found that Android systrace tool cannot show the callers of
iowait raised from io_schedule() on linux-4.14 LTS kernel.

Hi Andrew, could you kindly take this patch?

Thanks,
Gao Xiang

> 
> Thanks.
>