[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20160712141218.GT4695@ubuntu>
Date: Tue, 12 Jul 2016 07:12:18 -0700
From: Viresh Kumar <viresh.kumar@...aro.org>
To: Sergey Senozhatsky <sergey.senozhatsky@...il.com>
Cc: Petr Mladek <pmladek@...e.com>,
Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
Jan Kara <jack@...e.cz>, Tejun Heo <tj@...nel.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
vlevenetz@...sol.com, vaibhav.hiremath@...aro.org,
alex.elder@...aro.org, johan@...nel.org, akpm@...ux-foundation.org,
rostedt@...dmis.org
Subject: Re: [Query] Preemption (hogging) of the work handler
Hi Sergey,
On 12-07-16, 23:03, Sergey Senozhatsky wrote:
> Thanks, Petr.
>
>
> so, I'm looking at this thing now:
Thanks. Though just to mention, I have seen this only once yet :)
> : [ 12.874909] sched: RT throttling activated for rt_rq ffffffc0ac13fcd0 (cpu 0)
> : [ 12.874909] potential CPU hogs:
> : [ 12.874909] printk (292)
>
> so it's either cond_resched() does not reshed, keeping printk kthread
> active, which, however, upsets the sched and triggers throttling (umm, what);
>
> or we, somehow, have `console_may_schedule == 0' in this final console_unlock(),
> so cond_resched() never happens.
>
> I'm looking at mainline 3.10, tho.
My setup currently looks like this:
- 3.10
- + all printk patches from 3.10 to mainline
- + your patches
- Attaching my printk.c, so you can see the current state.
> Viresh, can you verify if we can do cond_resched() from console_unlock()
> (console_may_schedule != 0) ?
I will try that today.
--
viresh
View attachment "printk.c" of type "text/x-csrc" (88107 bytes)
Powered by blists - more mailing lists