Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762751AbZCYOWb (ORCPT ); Wed, 25 Mar 2009 10:22:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762155AbZCYOTB (ORCPT ); Wed, 25 Mar 2009 10:19:01 -0400 Received: from casper.infradead.org ([85.118.1.10]:33962 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762209AbZCYOTA (ORCPT ); Wed, 25 Mar 2009 10:19:00 -0400 Subject: RE: [patch 3/9] LTTng instrumentation tasklets From: Peter Zijlstra To: Chetan.Loke@Emulex.Com Cc: mingo@elte.hu, mathieu.desnoyers@polymtl.ca, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, ltt-dev@lists.casi.polymtl.ca, fweisbec@gmail.com, jbaron@redhat.com, tglx@linutronix.de, rmk+lkml@arm.linux.org.uk, mhiramat@redhat.com, fche@redhat.com, haoki@redhat.com, t-nishiie@np.css.fujitsu.com, rostedt@goodmis.org, eduard.munteanu@linux360.ro In-Reply-To: References: <20090324155625.420966314@polymtl.ca> <20090324160148.238795468@polymtl.ca> <20090324175621.GE31117@elte.hu> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Wed, 25 Mar 2009 15:17:58 +0100 Message-Id: <1237990678.7972.1094.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.26.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1044 Lines: 23 On Wed, 2009-03-25 at 06:52 -0700, Chetan.Loke@Emulex.Com wrote: > Quick question. I understand this is unrelated to this patch. So I > apologize in advance. > Ingo - you mentioned "tasklets are a legacy mechanism". Is there a > plan to phase them out ? Let me draw a small picture as to what's > bothering me. > > With the SR-IOV support if there are 'N' virtual functions then there > will be 'N' driver instances(actually N+1, 1 for the PF). If that > driver drains the responses in the interrupt context then all such > VF-instances could virtually block everyone else(because SR-IOV guys > might also have MSI-X enabled). > So now all such drivers should alter their Rx path.Driver's can queue > tasklets and can also get the performance they want. > > Any suggestions? Threaded interrupts? -- 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/