linux-kernel - Re: [RFC] sched: make callers check lock contention for cond_resched

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: <20120519011001.521acd09c636f97e38f000d6@gmail.com>
Date:	Sat, 19 May 2012 01:10:01 +0900
From:	Takuya Yoshikawa <takuya.yoshikawa@...il.com>
To:	Ingo Molnar <mingo@...nel.org>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	kvm@...r.kernel.org, avi@...hat.com, mtosatti@...hat.com,
	yoshikawa.takuya@....ntt.co.jp
Subject: Re: [RFC] sched: make callers check lock contention for
 cond_resched_lock()

On Fri, 18 May 2012 09:26:05 +0200
Ingo Molnar <mingo@...nel.org> wrote:

> I'm not sure we had a usable spin_is_contended() back then, nor 
> was the !PREEMPT case in my mind really.

The fact that both spin_needbreak() and spin_is_contended() can be
used outside of sched is a bit confusing.

For example, in mm/compaction.c we are using spin_is_contended(), but
in mm/memory.c spin_needbreak().

BTW, the actual users of spin_is_contended() look to be only:
	mm/compaction.c
	security/keys/gc.c

> ( The patch looks ugly though, in 99% of the lines it just does
>   something that cond_resched_lock() itself could do. )

Please ignore the patch.  I have already found a way to solve my
problem without cond_resched().

Thanks,
	Takuya
--
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/