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Message-ID: <1326361c-44c3-d2e0-c7a9-1e4b3e84ab6e@quicinc.com>
Date:   Wed, 17 Aug 2022 12:17:22 +0530
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Subject: Re: [PATCH v2] mm: oom_kill: add trace logs in process_mrelease()
 system call
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To:     Andrew Morton <akpm@linux-foundation.org>
CC:     <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>,
        <quic_charante@quicinc.com>, <quic_pkondeti@quicinc.com>
References: <20220816060017.17996-1-pbrahma@qti.qualcomm.com>
 <20220816173556.cb493d6a85edd65e1fa52911@linux-foundation.org>
From:   Pratyush Brahma <quic_pbrahma@quicinc.com>
In-Reply-To: <20220816173556.cb493d6a85edd65e1fa52911@linux-foundation.org>
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On 17-08-2022 06:05, Andrew Morton wrote:
> On Tue, 16 Aug 2022 11:30:17 +0530 Pratyush Brahma <pbrahma@qti.qualcomm.com> wrote:
>
>> The process_mrelease() system call[1] is used to release the memory of
>> a dying process from the context of the caller, which is similar to and
>> uses the functions of the oom reaper logic. There exists trace logs for
>> a process when reaped by the oom reaper. Just extend the same to when
>> done by the process_mrelease() system call.
> Why?  Please describe in full detail the end-user value of this change.

This patch provides information on how much memory is freed from a process
which is being reaped. Adding trace events in the process_mrelease() path when
process is being reaped would enable more holistic debug as it happens in
oom_reap_task_mm() currently.

This extends the debug functionality for the events as described in [1] to
the process_mrelease() system call. Now the coverage of trace events is complete.

[1]
https://lore.kernel.org/all/20170530185231.GA13412@castle/T/#u