From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: 2.6.20->2.6.21 - networking dies after random time Date: Thu, 26 Jul 2007 11:12:54 +0200 Message-ID: <20070726091254.GA8063@elte.hu> References: <20070724080534.GC18740@elte.hu> <20070724094202.GA11610@elte.hu> <20070724200431.GA22190@elte.hu> <1185322771.4175.102.camel@chaos> <4bacf17f0707260016x14fc1c92s628ae64353663833@mail.gmail.com> <20070726081326.GA3197@ff.dom.local> <1185437431.3227.21.camel@chaos> <20070726083120.GA26910@elte.hu> <20070726085523.GA3423@ff.dom.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Thomas Gleixner , Marcin ??lusarz , Linus Torvalds , Jean-Baptiste Vignaud , linux-kernel , shemminger , linux-net , netdev , Andrew Morton , Alan Cox To: Jarek Poplawski Return-path: Received: from mx3.mail.elte.hu ([157.181.1.138]:42880 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750969AbXGZJNG (ORCPT ); Thu, 26 Jul 2007 05:13:06 -0400 Content-Disposition: inline In-Reply-To: <20070726085523.GA3423@ff.dom.local> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org * Jarek Poplawski wrote: > On Thu, Jul 26, 2007 at 10:31:20AM +0200, Ingo Molnar wrote: > ... > > yeah. The patch below enables sw-resend on x86, to test the theory > > whether the APIC-driven hardware-vector-resend code has some problem. > > I think Marcin is using x86_64 (Athlon 64) yet. yeah - i meant to cover both arches but forgot about x86_64 - updated patch attached below. Ingo -----------------> Subject: x86: activate HARDIRQS_SW_RESEND From: Ingo Molnar activate the software-triggered IRQ-resend logic. it appears some chipsets/cpus do not handle local-APIC driven IRQ resends all that well, so always use the soft mechanism to trigger the execution of pending interrupts. Signed-off-by: Ingo Molnar --- arch/i386/Kconfig | 4 ++++ arch/x86_64/Kconfig | 4 ++++ kernel/irq/manage.c | 8 ++++++++ 3 files changed, 16 insertions(+) Index: linux-rt-rebase.q/arch/i386/Kconfig =================================================================== --- linux-rt-rebase.q.orig/arch/i386/Kconfig +++ linux-rt-rebase.q/arch/i386/Kconfig @@ -1284,6 +1284,10 @@ config GENERIC_PENDING_IRQ depends on GENERIC_HARDIRQS && SMP default y +config HARDIRQS_SW_RESEND + bool + default y + config X86_SMP bool depends on SMP && !X86_VOYAGER Index: linux-rt-rebase.q/arch/x86_64/Kconfig =================================================================== --- linux-rt-rebase.q.orig/arch/x86_64/Kconfig +++ linux-rt-rebase.q/arch/x86_64/Kconfig @@ -721,6 +721,10 @@ config GENERIC_PENDING_IRQ depends on GENERIC_HARDIRQS && SMP default y +config HARDIRQS_SW_RESEND + bool + default y + menu "Power management options" source kernel/power/Kconfig Index: linux-rt-rebase.q/kernel/irq/manage.c =================================================================== --- linux-rt-rebase.q.orig/kernel/irq/manage.c +++ linux-rt-rebase.q/kernel/irq/manage.c @@ -175,6 +175,14 @@ void enable_irq(unsigned int irq) desc->depth--; } spin_unlock_irqrestore(&desc->lock, flags); +#ifdef CONFIG_HARDIRQS_SW_RESEND + /* + * Do a bh disable/enable pair to trigger any pending + * irq resend logic: + */ + local_bh_disable(); + local_bh_enable(); +#endif } EXPORT_SYMBOL(enable_irq);