Re: [RFC][PATCH 00/12] various perf fixes

From: Dmitry Vyukov
Date: Mon Feb 15 2016 - 12:04:42 EST


On Mon, Feb 15, 2016 at 5:52 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> On Mon, Feb 15, 2016 at 05:38:36PM +0100, Dmitry Vyukov wrote:
>> Just to compensate the pain, here is what I've just got when
>> re-enabled perf in my config :)
>>
>> 2016/02/15 16:52:18 qemu-15: saving crash 'WARNING: CPU: 0 PID: 18465
>> at kernel/events/core.c:2743 ctx_sched_in+0x255/0x17f0()' to
>> crash-qemu-15-1455551538366997265
>> 2016/02/15 16:54:02 qemu-17: saving crash 'WARNING: CPU: 0 PID: 1072
>> at kernel/events/core.c:2743 ctx_sched_in+0x255/0x17f0()' to
>> crash-qemu-17-1455551642205132730
>> 2016/02/15 16:54:44 qemu-30: saving crash 'WARNING: CPU: 3 PID: 19858
>> at kernel/events/core.c:2122 __perf_install_in_context+0x1c4/0x220()'
>> to crash-qemu-30-1455551684741709699
>> 2016/02/15 16:55:02 qemu-20: saving crash 'WARNING: CPU: 2 PID: 9873
>> at kernel/events/core.c:226 event_function+0x359/0x3e0()' to
>> crash-qemu-20-1455551702744185903
>
> That looks like a splat every minute or so. I've now had it run for
> almost 10 minutes and I've not seen anything except:
>
> 2016/02/15 17:26:25 local-0: saving crash 'not executing programs' to crash-local-0-1455553585720015733
> 2016/02/15 17:29:25 local-0: saving crash 'not executing programs' to crash-local-0-1455553765740119317
> 2016/02/15 17:32:25 local-0: saving crash 'not executing programs' to crash-local-0-1455553945767974819
> 2016/02/15 17:35:25 local-0: saving crash 'not executing programs' to crash-local-0-1455554125793957186
>
> And those files are completely empty of useful.

There is something wrong and I guess it is not actually working.
Please post your config file so that I can double check. In
particular, did you set "cover": false?