From: David Miller <davem@davemloft.net>
To: akpm@linux-foundation.org
Cc: Yalin.Wang@sonymobile.com, kirill@shutemov.name, arnd@arndb.de,
linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
linux@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC] change non-atomic bitops method
Date: Tue, 03 Feb 2015 00:40:31 -0800 (PST) [thread overview]
Message-ID: <20150203.004031.593368249759204527.davem@davemloft.net> (raw)
In-Reply-To: <20150202223851.f30768d0.akpm@linux-foundation.org>
From: Andrew Morton <akpm@linux-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.
next prev parent reply other threads:[~2015-02-03 8:40 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-02 3:55 Wang, Yalin
2015-02-02 18:53 ` Laura Abbott
2015-02-02 19:31 ` Uwe Kleine-König
2015-02-02 23:29 ` Andrew Morton
2015-02-02 23:31 ` Russell King - ARM Linux
2015-02-03 1:17 ` Kirill A. Shutemov
2015-02-03 2:13 ` Wang, Yalin
2015-02-03 5:42 ` Wang, Yalin
2015-02-03 6:38 ` Andrew Morton
2015-02-03 7:03 ` Wang, Yalin
2015-02-03 8:42 ` Wang, Yalin
2015-02-03 10:59 ` Andrew Morton
2015-02-09 8:18 ` Wang, Yalin
2015-02-09 20:34 ` Andrew Morton
2015-02-10 7:05 ` Wang, Yalin
2015-02-09 21:42 ` Rasmus Villemoes
2015-02-03 8:40 ` David Miller [this message]
2015-02-03 8:48 ` Andrew Morton
2015-02-03 9:34 ` Rasmus Villemoes
2015-02-03 9:41 ` Wang, Yalin
2015-02-03 10:39 ` Kirill A. Shutemov
2015-02-03 15:14 ` David Howells
2015-02-03 19:10 ` Uwe Kleine-König
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