linux-kernel - Re: /proc/lock

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:	Wed, 21 May 2008 07:09:02 -0400
From:	"Alan D. Brunelle" <Alan.Brunelle@...com>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>
CC:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: /proc/lock_stat "stuck"

Peter Zijlstra wrote:
> On Tue, 2008-05-20 at 14:09 -0400, Alan D. Brunelle wrote:
>> I'm attempting to use /proc/lock_stat to gather some information during
>> some benchmarking runs, but what I find happens is as follows:
>>
>> 1. I boot the system - 2.6.26-rc3 kernel + CONFIG_LOCK_STAT=y
>>
>> 2. I can then look at /proc/lock_stat, and it has valid-looking values
>>
>> 3. I wait a while, do some stuff, but when I look at /proc/lock_stat
>> again the values have not changed.
>>
>> 4. If I clear the counters - echo 0 > /proc/lock_stat - the counters
>> never increase, and no information besides the headers are output when I
>> cat /proc/lock_stat.
>>
>>
>> Is there something that one needs to do to get counter updates?
> 
> Did you get lockdep warnings? Those disable all lock debugging,
> including lockstat.

Hi Peter -

Yesterday, during boots I /was/ getting a problem with NVIDIA ck804xrom
registration problems -  "Unable to register resource" - it did produce
a stack trace w/ lock calls in the stack. Since then I've cut /way/ back
on my .config, and I don't see that problem anymore, and the lock stats
seem to be updating correctly with this new .config. [If I have time
later today, I'll go back to the old .config and try to track down the
ck804xrom issue.]

Thanks for the hint about watching for lockdep issues,
Alan
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/