linux-kernel - Re: [RFC] change non-atomic bitops method

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]

Date:	Tue, 03 Feb 2015 00:40:31 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	akpm@...ux-foundation.org
Cc:	Yalin.Wang@...ymobile.com, kirill@...temov.name, arnd@...db.de,
	linux-arch@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux@....linux.org.uk, linux-arm-kernel@...ts.infradead.org
Subject: Re: [RFC] change non-atomic bitops method

From: Andrew Morton <akpm@...ux-foundation.org>
Date: Mon, 2 Feb 2015 22:38:51 -0800

> It is only with both these ratios that we can work out whether the
> patch is a net gain.  My suspicion is that set_bit on an already-set
> bit is so rare that the patch will be a loss.

A common pattern is implementing a "referenced" bit, and in that case
the bit is often already set, and in such a scenerio the proposed
change is a huge win.

--
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/