Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753353Ab2EMU3d (ORCPT ); Sun, 13 May 2012 16:29:33 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:34656 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753092Ab2EMU3b (ORCPT ); Sun, 13 May 2012 16:29:31 -0400 Message-ID: <4FB0197F.6010000@linux.vnet.ibm.com> Date: Mon, 14 May 2012 01:58:47 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120424 Thunderbird/12.0 MIME-Version: 1.0 To: John David Anglin CC: Linus Torvalds , "akpm@linux-foundation.org" , Ingo Molnar , Peter Zijlstra , Mikulas Patocka , stepanm@codeaurora.org, Thomas Gleixner , James.Bottomley@hansenpartnership.com, deller@gmx.de, dhowells@redhat.com, yasutake.koichi@jp.panasonic.com, eike-kernel@sf-tec.de, linux-parisc@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: Linux 3.4-rc7 References: <4FB011E7.1000604@linux.vnet.ibm.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit x-cbid: 12051310-1618-0000-0000-000001937D71 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2371 Lines: 78 On 05/14/2012 01:38 AM, John David Anglin wrote: > On 13-May-12, at 3:56 PM, Srivatsa S. Bhat wrote: > >> The regression was introduced in the 3.4 merge window itself (by commit >> 5fbd036b55 "sched: Cleanup cpu_active madness"). >> >> Links to the original posting: >> PA_RISC: http://marc.info/?l=linux-parisc&m=133241790810604&w=2 > > > If I had the above change, I get > > CHK include/generated/compile.h > CC arch/parisc/kernel/smp.o > arch/parisc/kernel/smp.c: In function 'smp_cpu_init': > arch/parisc/kernel/smp.c:300:2: error: implicit declaration of function > 'notify_cpu_starting' [-Werror=implicit-function-declaration] > cc1: some warnings being treated as errors > make[1]: *** [arch/parisc/kernel/smp.o] Error 1 > Sorry about that. I neither have the hardware nor the toolchain to test it. I guess this problem doesn't exist for mn10300 since it already includes linux/cpu.h when CONFIG_HOTPLUG_CPU=y Does the below updated patch help for PA-RISC? ---- From: Srivatsa S. Bhat parisc/CPU hotplug: Add missing call to notify_cpu_starting() The scheduler depends on receiving the CPU_STARTING notification, without which we end up into a lot of trouble. So add the missing call to notify_cpu_starting() in the bringup code. Signed-off-by: Srivatsa S. Bhat --- arch/parisc/kernel/smp.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 0bb1d63..4dc7b79 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -295,8 +296,13 @@ smp_cpu_init(int cpunum) printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum); machine_halt(); - } + } + + notify_cpu_starting(cpunum); + + ipi_call_lock(); set_cpu_online(cpunum, true); + ipi_call_unlock(); /* Initialise the idle task for this CPU */ atomic_inc(&init_mm.mm_count); -- 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/