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From: Cesar Eduardo Barros <cesarb@cesarb.net>
To: Cesar Eduardo Barros <cesarb@cesarb.net>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org, rolandd@cisco.com,
	dwalker@fifo99.com
Subject: Re: [PATCH] WARN_ONCE(): use bool for condition
Date: Tue, 29 Sep 2009 20:18:10 -0300	[thread overview]
Message-ID: <4AC295B2.3000503@cesarb.net> (raw)
In-Reply-To: <4AC2943E.2070502@cesarb.net>

Cesar Eduardo Barros escreveu:
> Andrew Morton escreveu:
>> On Sun, 27 Sep 2009 15:25:12 -0300
>> Cesar Eduardo Barros <cesarb@cesarb.net> wrote:
>>
>>> Use the type bool for __ret_warn_once and __ret_warn_on, instead of int
>>> with a double negation. This matches the intent of the code better and
>>> should allow the compiler to generate better code, like in commit
>>> 70867453092297be9afb2249e712a1f960ec0a09. However, some versions of gcc
>>> seems to pessimize the code instead when the condition is not trivial.
>>
>> It would be nice if we had some accurate numbers on the kernel size
>> reductions from this, please.  I assume that the patch is still of
>> benefit in 2.6.32-rc1(2?), but it's always good to confirm.
> 
> In the first patch, Daniel Walker saw a decrease of 504 bytes in IA-32, 
> and I saw a decrease of 1462 bytes in x86-64 defconfig. I will resend it 
> 
> For this one, on the other hand, I am not sure whether it should be 
> included or dropped. While Daniel Walker saw a decrease of 84 bytes in 
> IA-32, I saw an *increase* of 598 bytes in x86-64 defconfig. It seems 

Forgot to mention, all my testing was against v2.6.31-9194-g0d9df25

-- 
Cesar Eduardo Barros
cesarb@cesarb.net
cesar.barros@gmail.com

      parent reply	other threads:[~2009-09-29 23:18 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-09-27 13:53 [PATCH] WARN_ONCE(): use bool for boolean flag Cesar Eduardo Barros
2009-09-27 14:03 ` Daniel Walker
2009-09-27 15:56   ` Cesar Eduardo Barros
2009-09-27 16:52     ` Daniel Walker
2009-09-27 17:24       ` Cesar Eduardo Barros
2009-09-27 17:32         ` Daniel Walker
2009-09-27 17:48           ` Cesar Eduardo Barros
2009-09-27 18:12             ` Cesar Eduardo Barros
2009-09-27 18:25               ` [PATCH] WARN_ONCE(): use bool for condition Cesar Eduardo Barros
2009-09-27 18:28                 ` Daniel Walker
2009-09-27 18:55                   ` Cesar Eduardo Barros
2009-09-27 19:03                     ` Daniel Walker
2009-09-29 20:59                 ` Andrew Morton
2009-09-29 23:11                   ` Cesar Eduardo Barros
2009-09-29 23:12                     ` [PATCH] WARN_ONCE(): use bool for boolean flag Cesar Eduardo Barros
2009-09-30  0:17                       ` Andrew Morton
2009-09-30  0:37                         ` Cesar Eduardo Barros
2009-09-29 23:18                     ` Cesar Eduardo Barros [this message]

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