Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933982Ab1FWRnc (ORCPT ); Thu, 23 Jun 2011 13:43:32 -0400 Received: from mail.windriver.com ([147.11.1.11]:35634 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933842Ab1FWRim (ORCPT ); Thu, 23 Jun 2011 13:38:42 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Robert Richter , Ingo Molnar , Paul Gortmaker Subject: [34-longterm 228/247] arch/x86/oprofile/op_model_amd.c: Perform initialisation on a single CPU Date: Thu, 23 Jun 2011 13:34:56 -0400 Message-Id: <1308850515-15242-169-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> References: <1308849690-14530-1-git-send-email-paul.gortmaker@windriver.com> <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2972 Lines: 90 From: Robert Richter ------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. ------------------- commit c7c25802b39c443b3745cfa973dc49a97a3491f8 upstream. Disable preemption in init_ibs(). The function only checks the ibs capabilities and sets up pci devices (if necessary). It runs only on one cpu but operates with the local APIC and some MSRs, thus it is better to disable preemption. [ 7.034377] BUG: using smp_processor_id() in preemptible [00000000] code: modprobe/483 [ 7.034385] caller is setup_APIC_eilvt+0x155/0x180 [ 7.034389] Pid: 483, comm: modprobe Not tainted 2.6.37-rc1-20101110+ #1 [ 7.034392] Call Trace: [ 7.034400] [] debug_smp_processor_id+0xd2/0xf0 [ 7.034404] [] setup_APIC_eilvt+0x155/0x180 [ ... ] Addresses https://bugzilla.kernel.org/show_bug.cgi?id=22812 Reported-by: Signed-off-by: Robert Richter Cc: oprofile-list@lists.sourceforge.net Cc: Peter Zijlstra Cc: Frederic Weisbecker Cc: Rafael J. Wysocki Cc: Dan Carpenter Cc: Andrew Morton LKML-Reference: <20110103111514.GM4739@erda.amd.com> [ small cleanups ] Signed-off-by: Ingo Molnar Signed-off-by: Paul Gortmaker --- arch/x86/oprofile/op_model_amd.c | 24 ++++++++++++++++-------- 1 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c index 090cbbe..c8f46aa 100644 --- a/arch/x86/oprofile/op_model_amd.c +++ b/arch/x86/oprofile/op_model_amd.c @@ -497,21 +497,29 @@ static void clear_ibs_nmi(void) on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1); } -/* initialize the APIC for the IBS interrupts if available */ +/* + * check and reserve APIC extended interrupt LVT offset for IBS if + * available + * + * init_ibs() preforms implicitly cpu-local operations, so pin this + * thread to its current CPU + */ + static void ibs_init(void) { - ibs_caps = get_ibs_caps(); + preempt_disable(); + ibs_caps = get_ibs_caps(); if (!ibs_caps) - return; + goto out; - if (init_ibs_nmi()) { + if (init_ibs_nmi() < 0) ibs_caps = 0; - return; - } + else + printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n", ibs_caps); - printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n", - (unsigned)ibs_caps); +out: + preempt_enable(); } static void ibs_exit(void) -- 1.7.4.4 -- 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/