linux-kernel - Re: LatencyTOP infrastructure patch

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <4794C554.4000200@linux.intel.com>
Date:	Mon, 21 Jan 2008 08:16:20 -0800
From:	Arjan van de Ven <arjan@...ux.intel.com>
To:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
CC:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Ingo Molnar <mingo@...e.hu>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: LatencyTOP infrastructure patch

KOSAKI Motohiro wrote:
> Hi
> 
>> +static void __sched
>> +account_global_scheduler_latency(struct task_struct *tsk, int usecs)
>> +{
>> +	int i;
>> +	int firstnonnull = MAXLR + 1;
>> +
>> +	if (!tsk->latency_reason.reason)
>> +		return;
>> +
>> +	/* skip kernel threads for now */
>> +	if (!tsk->mm)
>> +		return;
> 
> Why do you ignore kernel thread?
> 
> may be, some network filesystem use kernel thread for local I/O.
> What do you think it?

kernel threads (by themselves) don't tend to result in user visible latency...
at least that's my assumption so far... if you think I'm wrong... I'm open to be shown
that we should count them.
--
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/