Date: Mon, 6 Jun 2011 15:11:01 -0700
From: Josh Triplett <josh@joshtriplett.org>
To: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>,
        WANG Cong <xiyou.wangcong@gmail.com>, Sam Ravnborg <sam@ravnborg.org>,
        Jeff Dike <jdike@addtoit.com>, Andi Kleen <andi@firstfloor.org>,
        Huang Ying <ying.huang@intel.com>, Li Wei <W.Li@Sun.COM>,
        Michael Ellerman <michaele@au1.ibm.com>, Ingo Molnar <mingo@elte.hu>,
        Heiko Carstens <heicars2@linux.vnet.ibm.com>,
        Martin Schwidefsky <mschwid2@linux.vnet.ibm.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Disable CONFIG_CONSTRUCTORS when not needed by
 CONFIG_GCOV_KERNEL
Message-ID: <20110606221101.GC1999@leaf>
References: <20110605082100.GA18151@leaf>
 <4DECB261.5090109@linux.vnet.ibm.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <4DECB261.5090109@linux.vnet.ibm.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1362
Lines: 33

On Mon, Jun 06, 2011 at 12:56:33PM +0200, Peter Oberparleiter wrote:
> On 05.06.2011 10:21, Josh Triplett wrote:
> >CONFIG_CONSTRUCTORS controls support for running constructor functions
> >at kernel init time.  According to commit
> >b99b87f70c7785ab1e253c6220f4b0b57ce3a7f7, gcov (CONFIG_GCOV_KERNEL)
> >needs this.  However, CONFIG_CONSTRUCTORS currently defaults to y, with
> >no option to disable it, and CONFIG_GCOV_KERNEL depends on it.  Instead,
> >default it to n and have CONFIG_GCOV_KERNEL select it, so that the
> >normal case of CONFIG_GCOV_KERNEL=n will result in
> >CONFIG_CONSTRUCTORS=n.
> >
> >Observed in the short list of =y values in a minimal kernel
> >configuration.
> >
> >Signed-off-by: Josh Triplett<josh@joshtriplett.org>
> >---
> 
> I tested this patch and GCOV profiling still works with it applied.
> To my knowledge, GCOV profiling is the only kernel mechanism using
> GCC's constructors and this may save some bytes.
> 
> Acked-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>

Excellent, thanks for testing and acking.

What tree should this patch go through?

- Josh Triplett
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/