linux-kernel - Re: [PATCH v2] scheduler: enhancement to show_state

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 8 Aug 2017 16:50:23 +0800
From:   Yafang Shao <laoar.shao@...il.com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     gregkh@...uxfoundation.org, jslaby@...e.com, mingo@...hat.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] scheduler: enhancement to show_state_filter

Hi Peter,

The point is we call use it as bellow,
    show_state_filter(TASK_RUNNING);
because TASK_RUNNING is 0, that will dump all tasks.

Under some circumstance, we need this to dump only tasks in TASK_RUNNING state.

Thanks
Yafang

2017-08-08 16:30 GMT+08:00 Peter Zijlstra <peterz@...radead.org>:
> On Tue, Aug 08, 2017 at 08:53:10PM +0800, Yafang Shao wrote:
>> Sometimes we want to get tasks in TASK_RUNNING sepcifically,
>> instead of dump all tasks.
>> For example, when the loadavg are high, we want to dump
>> tasks in TASK_RUNNING and TASK_UNINTERRUPTIBLE, which contribute
>> to system load. But mostly there're lots of tasks in Sleep state,
>> which occupies almost all of the kernel log buffer, even overflows
>> it, that causes the useful messages get lost. Although we can
>> enlarge the kernel log buffer, but that's not a good idea.
>>
>> So I made this change to make the show_state_filter more flexible,
>> and then we can dump the tasks in TASK_RUNNING specifically.
>
> It reads like magic and I really don't see the point.