From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH 2/11] x86: convert to generic helpers for IPI function calls Date: Tue, 22 Apr 2008 21:12:13 +0200 Message-ID: <20080422191213.GA6370@elte.hu> References: <1208890227-24808-1-git-send-email-jens.axboe@oracle.com> <1208890227-24808-3-git-send-email-jens.axboe@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-arch-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: To: Linus Torvalds Cc: Jens Axboe , linux-arch-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Linux Kernel Mailing List , npiggin-l3A5Bk7waGM@public.gmane.org, peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, sam-uyr5N9Q2VtJg9hUCZPvPmw@public.gmane.org * Linus Torvalds wrote: > > [ Ingo added to cc, since this is x86-specific ] > > On Tue, 22 Apr 2008, Jens Axboe wrote: > > +++ b/arch/x86/kernel/apic_32.c > > @@ -1357,6 +1357,10 @@ void __init smp_intr_init(void) > > > > /* IPI for generic function call */ > > set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt); > > + > > + /* IPI for single call function */ > > + set_intr_gate(CALL_FUNCTION_SINGLE_VECTOR, > > + call_function_single_interrupt); > > Ok, one more comment.. > > Why bother with separate vectors for this? this was my first question a month ago when Jens/Nick first submitted it :) > Or is it just a performance optimization? [...] yes and i gave in - Nick and Jens wants to do some crazy stuff and they had the numbers. Here's the previous discussion: http://lkml.org/lkml/2008/2/27/125 Ingo From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.mail.elte.hu ([157.181.151.9]:53446 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761712AbYDVTM5 (ORCPT ); Tue, 22 Apr 2008 15:12:57 -0400 Date: Tue, 22 Apr 2008 21:12:13 +0200 From: Ingo Molnar Subject: Re: [PATCH 2/11] x86: convert to generic helpers for IPI function calls Message-ID: <20080422191213.GA6370@elte.hu> References: <1208890227-24808-1-git-send-email-jens.axboe@oracle.com> <1208890227-24808-3-git-send-email-jens.axboe@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-arch-owner@vger.kernel.org List-ID: To: Linus Torvalds Cc: Jens Axboe , linux-arch@vger.kernel.org, Linux Kernel Mailing List , npiggin@suse.de, peterz@infradead.org, sam@ravnborg.org Message-ID: <20080422191213.mBYnmOkSkSmedAQC6D8KKV5qOS2mmQgSTK7unJfjZ1I@z> * Linus Torvalds wrote: > > [ Ingo added to cc, since this is x86-specific ] > > On Tue, 22 Apr 2008, Jens Axboe wrote: > > +++ b/arch/x86/kernel/apic_32.c > > @@ -1357,6 +1357,10 @@ void __init smp_intr_init(void) > > > > /* IPI for generic function call */ > > set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt); > > + > > + /* IPI for single call function */ > > + set_intr_gate(CALL_FUNCTION_SINGLE_VECTOR, > > + call_function_single_interrupt); > > Ok, one more comment.. > > Why bother with separate vectors for this? this was my first question a month ago when Jens/Nick first submitted it :) > Or is it just a performance optimization? [...] yes and i gave in - Nick and Jens wants to do some crazy stuff and they had the numbers. Here's the previous discussion: http://lkml.org/lkml/2008/2/27/125 Ingo