Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934167Ab3JPMOW (ORCPT ); Wed, 16 Oct 2013 08:14:22 -0400 Received: from mail-we0-f181.google.com ([74.125.82.181]:51183 "EHLO mail-we0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932406Ab3JPMOV (ORCPT ); Wed, 16 Oct 2013 08:14:21 -0400 Date: Wed, 16 Oct 2013 14:14:17 +0200 From: Frederic Weisbecker To: linux-kernel@vger.kernel.org, mingo@kernel.org, hpa@zytor.com, linux-arm-kernel@lists.infradead.org, rmk@arm.linux.org.uk, paulmck@linux.vnet.ibm.com, tglx@linutronix.de, khilman@linaro.org Cc: linux-tip-commits@vger.kernel.org Subject: Re: [tip:timers/core] ARM: Kconfig: allow full nohz CPU accounting Message-ID: <20131016121416.GD12773@localhost.localdomain> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2157 Lines: 54 On Thu, Oct 03, 2013 at 06:58:03AM -0700, tip-bot for Kevin Hilman wrote: > Commit-ID: 31c1fc8187158cb80ccd57c19e024c55af901797 > Gitweb: http://git.kernel.org/tip/31c1fc8187158cb80ccd57c19e024c55af901797 > Author: Kevin Hilman > AuthorDate: Mon, 16 Sep 2013 15:28:22 -0700 > Committer: Frederic Weisbecker > CommitDate: Mon, 30 Sep 2013 15:37:05 +0200 > > ARM: Kconfig: allow full nohz CPU accounting > > With the 64-bit requirement removed from VIRT_CPU_ACCOUNTING_GEN, > allow ARM platforms to enable it. Since VIRT_CPU_ACCOUNTING_GEN is a > dependency for full NO_HZ, this allows ARM platforms to enable full > NO_HZ as well. I realize that arm doesn't implement irq work raise. It hooks on the timer to execute pending irq work. You'll need to implement arch_irq_work_raise() and implement some sort of self IPI to trigger irq work. The full dynticks subsystem relies on that to work correctly. It often use that to re-evaluate and possibly restart the tick after scheduler, posix timer updates, etc... That notwithstanding that if you have no tick, tick based irq work can't work. Thanks. > > Signed-off-by: Kevin Hilman > Cc: Ingo Molnar > Cc: Russell King > Cc: Paul E. McKenney > Cc: Arm Linux > Signed-off-by: Frederic Weisbecker > --- > arch/arm/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 1ad6fb6..323baf0 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -54,6 +54,7 @@ config ARM > select HAVE_REGS_AND_STACK_ACCESS_API > select HAVE_SYSCALL_TRACEPOINTS > select HAVE_UID16 > + select HAVE_VIRT_CPU_ACCOUNTING_GEN > select IRQ_FORCED_THREADING > select KTIME_SCALAR > select MODULES_USE_ELF_REL -- 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/