From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 3/11] powerpc: convert to generic helpers for IPI function calls Date: Tue, 22 Apr 2008 20:51:12 +0200 Message-ID: <20080422185111.GS12774@kernel.dk> References: <1208851058-8500-1-git-send-email-jens.axboe@oracle.com> <1208851058-8500-4-git-send-email-jens.axboe@oracle.com> <18445.54284.194023.553595@cargo.ozlabs.ibm.com> <20080422121315.GE12774@kernel.dk> <18445.56653.957832.720681@cargo.ozlabs.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <18445.56653.957832.720681-UYQwCShxghk5kJ7NmlRacFaTQe2KTcn/@public.gmane.org> Sender: linux-arch-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: To: Paul Mackerras Cc: linux-arch-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, npiggin-l3A5Bk7waGM@public.gmane.org, torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, anton-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org On Tue, Apr 22 2008, Paul Mackerras wrote: > Jens Axboe writes: > > > I touched on both of these points in the initial mail, but perhaps you > > missed it as I didn't CC everyone for the 0/11 part. I'll add the full > > explanation to the 1/11 patch as well. > > OK, that would be fine. I didn't read right to the end of the 0/11 > mail in detail, I admit. :) I don't blame you :-) > Now that I have, I don't see anything about smp_send_stop trying to > get the interrupt sent off in a panic situation when some other cpu > might be stuck holding the lock (unless that's the "ipi_lock is a > little muddy" part, but that only talks about cpu onlining). That bit > looks to be powerpc-specific, added in commit e057d985 in December > 2007, so perhaps a mention that that has gone away now in the > description for 3/11 would be good. Oh that, yes I'll add a description. I didn't really think there was much need for it anymore, but it should at least be documented. The ipi_lock stuff was really more about stopping IPIs completely, not the smp_send_stop() panic() you described. -- Jens Axboe From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from brick.kernel.dk ([87.55.233.238]:27654 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764160AbYDVSvU (ORCPT ); Tue, 22 Apr 2008 14:51:20 -0400 Date: Tue, 22 Apr 2008 20:51:12 +0200 From: Jens Axboe Subject: Re: [PATCH 3/11] powerpc: convert to generic helpers for IPI function calls Message-ID: <20080422185111.GS12774@kernel.dk> References: <1208851058-8500-1-git-send-email-jens.axboe@oracle.com> <1208851058-8500-4-git-send-email-jens.axboe@oracle.com> <18445.54284.194023.553595@cargo.ozlabs.ibm.com> <20080422121315.GE12774@kernel.dk> <18445.56653.957832.720681@cargo.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <18445.56653.957832.720681@cargo.ozlabs.ibm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Paul Mackerras Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, npiggin@suse.de, torvalds@linux-foundation.org, anton@samba.org Message-ID: <20080422185112.3uG6qzbArFdJQ3LJSHnxZaE6thNM-aZfKc0X_AnVC74@z> On Tue, Apr 22 2008, Paul Mackerras wrote: > Jens Axboe writes: > > > I touched on both of these points in the initial mail, but perhaps you > > missed it as I didn't CC everyone for the 0/11 part. I'll add the full > > explanation to the 1/11 patch as well. > > OK, that would be fine. I didn't read right to the end of the 0/11 > mail in detail, I admit. :) I don't blame you :-) > Now that I have, I don't see anything about smp_send_stop trying to > get the interrupt sent off in a panic situation when some other cpu > might be stuck holding the lock (unless that's the "ipi_lock is a > little muddy" part, but that only talks about cpu onlining). That bit > looks to be powerpc-specific, added in commit e057d985 in December > 2007, so perhaps a mention that that has gone away now in the > description for 3/11 would be good. Oh that, yes I'll add a description. I didn't really think there was much need for it anymore, but it should at least be documented. The ipi_lock stuff was really more about stopping IPIs completely, not the smp_send_stop() panic() you described. -- Jens Axboe