linux-kernel - Re: [PATCH v2 3/7] signal: retarget_shared_pending: optimize while_each

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

Message-ID: <20110422132657.646f1774@mfleming-mobl1.ger.corp.intel.com>
Date:	Fri, 22 Apr 2011 13:26:57 +0100
From:	Matt Fleming <matt@...sole-pimps.org>
To:	Oleg Nesterov <oleg@...hat.com>
Cc:	Tejun Heo <tj@...nel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	"Nikita V. Youshchenko" <nyoushchenko@...sta.com>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 3/7] signal: retarget_shared_pending: optimize
 while_each_thread() loop

On Mon, 18 Apr 2011 15:45:18 +0200
Oleg Nesterov <oleg@...hat.com> wrote:

> retarget_shared_pending() blindly does recalc_sigpending_and_wake() for
> every sub-thread, this is suboptimal. We can check t->blocked and stop
> looping once every bit in shared_pending has the new target.
> 
> Note: we do not take task_is_stopped_or_traced(t) into account, we are
> not trying to speed up the signal delivery or to avoid the unnecessary
> (but harmless) signal_wake_up(0) in this unlikely case.
> 
> Signed-off-by: Oleg Nesterov <oleg@...hat.com>

Nice.

Reviewed-by: Matt Fleming <matt.fleming@...ux.intel.com>

--
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/