linux-kernel - Re: [PATCH] bitops: simplify generic bit finding functions

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: <874p9liwgi.fsf@basil.nowhere.org>
Date:	Mon, 28 Apr 2008 21:57:33 +0200
From:	Andi Kleen <andi@...stfloor.org>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Thomas Gleixner <tglx@...utronix.de>,
	Harvey Harrison <harvey.harrison@...il.com>,
	Ingo Molnar <mingo@...e.hu>,
	Andrew Morton <akpm@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	David Miller <davem@...emloft.net>
Subject: Re: [PATCH] bitops: simplify generic bit finding functions

Linus Torvalds <torvalds@...ux-foundation.org> writes:
>
> Is there a real hot path anywhere that actually uses this and depends on 
> it?

A long time ago during profiling I found that in the scheduler back then
for_each_cpu() with find_next_bit() was somewhat hot. But I'm not sure it 
still would be in the new scheduler anyways and the test case a little
dumb anyways (overscheduling user space)

Still I think for_each_cpu() should be reasonably stream lined code.

-Andi
--
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/