From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 1/10] Add generic helpers for arch IPI function calls Date: Wed, 7 May 2008 22:42:52 +0200 Message-ID: <20080507204251.GO16217@kernel.dk> References: <20080430123717.GC12774@kernel.dk> <20080502020241.GA26088@linux.vnet.ibm.com> <20080502021233.GC11844@wotan.suse.de> <20080502122955.GB15522@linux.vnet.ibm.com> <20080502124205.GA23680@linux.vnet.ibm.com> <1209733169.13978.157.camel@twins> <20080503054930.GA19664@wotan.suse.de> <20080503181148.GA16159@linux.vnet.ibm.com> <20080505041533.GA17640@wotan.suse.de> <20080505174312.GC7543@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from brick.kernel.dk ([87.55.233.238]:9092 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758545AbYEGUm7 (ORCPT ); Wed, 7 May 2008 16:42:59 -0400 Content-Disposition: inline In-Reply-To: <20080505174312.GC7543@linux.vnet.ibm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: "Paul E. McKenney" Cc: Nick Piggin , Peter Zijlstra , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, jeremy@goop.org, mingo@elte.hu On Mon, May 05 2008, Paul E. McKenney wrote: > OK. The below still permits parallel smp_call_function() > and smp_call_function_mask() as well as permitting parallel > smp_call_function_single(). It prohibits the irq-disabled case. > > Thoughts? Sorry for the delayed response here. The below looks pretty good to me, though it'll require a few modifications to fixup smp_call_function() from irq disabled context. But that's doable, though I have to do a grep over the kernel to check everything (I remember CPU send_stop being one such path). Not a huge fan of such an interface, but hey... Is everyone OK with going this route, initially at least? It's the lesser of all evils, I think. > diff --git a/arch/Kconfig b/arch/Kconfig > index a5a0184..5ae9360 100644 > --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -38,4 +38,4 @@ config HAVE_KRETPROBES > def_bool n > > config USE_GENERIC_SMP_HELPERS > - def_bool n > + def_bool y This part puzzled me, why? We default to 'n' and let converted archs opt-in, so I don't get this part of your patch... -- Jens Axboe