From patchwork Mon May 6 08:04:40 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 241607 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id BF09A2C01AB for ; Mon, 6 May 2013 19:15:26 +1000 (EST) Received: by ozlabs.org (Postfix) id C0F762C00E5; Mon, 6 May 2013 19:15:02 +1000 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: from e23smtp08.au.ibm.com (e23smtp08.au.ibm.com [202.81.31.141]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp08.au.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 918AA2C00E7 for ; Mon, 6 May 2013 19:14:46 +1000 (EST) Received: from /spool/local by e23smtp08.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 6 May 2013 18:39:47 +1000 Received: from d23dlp03.au.ibm.com (202.81.31.214) by e23smtp08.au.ibm.com (202.81.31.205) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 6 May 2013 18:39:38 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 3487C3578A81 for ; Mon, 6 May 2013 18:05:03 +1000 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r4684tCF16973838 for ; Mon, 6 May 2013 18:04:56 +1000 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r4685194017352 for ; Mon, 6 May 2013 18:05:02 +1000 Received: from polynomials.in.ibm.com (polynomials.in.ibm.com [9.124.35.35]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id r4684x92017179; Mon, 6 May 2013 18:05:00 +1000 From: Anshuman Khandual To: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH] powerpc, perf: Clear out branch entries to avoid any previous stale values Date: Mon, 6 May 2013 13:34:40 +0530 Message-Id: <1367827480-5375-1-git-send-email-khandual@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.11.7 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13050608-5140-0000-0000-0000032555D8 Cc: mikey@neuling.org X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" The 'to' field inside branch entries might contain stale values from previous PMU interrupt instances which had indirect branches. So clear all the values before reading a fresh set of BHRB entries after a PMU interrupt. Signed-off-by: Anshuman Khandual --- arch/powerpc/perf/core-book3s.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index c627843..09db68d 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -1590,6 +1590,8 @@ static void record_and_restart(struct perf_event *event, unsigned long val, if (event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK) { struct cpu_hw_events *cpuhw; cpuhw = &__get_cpu_var(cpu_hw_events); + memset(cpuhw->bhrb_entries, 0, + sizeof(struct perf_branch_entry) * BHRB_MAX_ENTRIES); power_pmu_bhrb_read(cpuhw); data.br_stack = &cpuhw->bhrb_stack; }