From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mse2fe1.mse2.exchange.ms (outbound.mse2.exchange.ms [69.25.50.247]) by ozlabs.org (Postfix) with ESMTP id 788A6DDE20 for ; Thu, 30 Aug 2007 09:56:12 +1000 (EST) Message-ID: <46D604BF.7090905@bluelane.com> Date: Wed, 29 Aug 2007 16:43:59 -0700 From: Pete/Piet Delaney MIME-Version: 1.0 To: Jason Wessel Subject: Re: [Kgdb-bugreport] 2.6.23-rc3-mm1: kgdb build failure on powerpc References: <20070822020648.5ea3a612.akpm@linux-foundation.org> <200708222104.29432.m.kozlowski@tuxland.pl> <20070822124743.fc316963.akpm@linux-foundation.org> <46CCBC3C.7010307@windriver.com> <20070822165318.b82da13c.akpm@linux-foundation.org> <46CCFE2C.4050306@windriver.com> In-Reply-To: <46CCFE2C.4050306@windriver.com> Content-Type: text/plain; charset=ISO-8859-1 Cc: kgdb-bugreport@lists.sourceforge.net, amitkale@linsyssoft.com, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Mariusz Kozlowski , Paul Mackerras , Andrew Morton Reply-To: pete@bluelane.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jason Wessel wrote: > Andrew Morton wrote: >> On Wed, 22 Aug 2007 17:44:12 -0500 >> Jason Wessel wrote: >> >> >>> + while (!atomic_read(&debugger_active)); >>> >> >> eek. We're in the process of hunting down and eliminating exactly this >> construct. There have been cases where the compiler cached the >> atomic_read() result in a register, turning the above into an infinite >> loop. >> >> Plus we should never add power-burners like that into the kernel >> anyway. That loop should have a cpu_relax() in it. Which will also >> fix the >> compiler problem described above. >> >> > Agreed, and fixed with a cpu_relax. > >> Thirdly, please always add a newline when coding statements like that: >> >> while (expr()) >> ; >> > > The other instances I found of the same problem in the kgdb core are > fixed too. > > I merged all the changes into the for_mm branch in the kgdb git tree. Where is the kgdb git tree? - -piet > > Thanks, > Jason. > - > 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/ > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFG1gS/JICwm/rv3hoRAhfRAJ42F3QlzGwG4aQbs9hHVMI4kJ9SWQCfXrku UGo97ByKsB9yhyIu5c+2Jh0= =welB -----END PGP SIGNATURE-----