Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758949Ab3FMX2J (ORCPT ); Thu, 13 Jun 2013 19:28:09 -0400 Received: from mx1.corp.phx1.mozilla.com ([63.245.216.69]:41096 "EHLO smtp.mozilla.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752483Ab3FMX2H (ORCPT ); Thu, 13 Jun 2013 19:28:07 -0400 X-Greylist: delayed 414 seconds by postgrey-1.27 at vger.kernel.org; Thu, 13 Jun 2013 19:28:07 EDT Date: Thu, 13 Jun 2013 16:21:11 -0700 From: Jed Davis To: Peter Zijlstra , Paul Mackerras , Ingo Molnar , Arnaldo Carvalho de Melo , Will Deacon , Russell King , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] perf: ARM: Record the user-mode PC in the call chain. Message-ID: <20130613232111.GA12536@mozilla.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-User-Agent-Host: Linux nimbostratus 3.2.0-4-amd64 x86_64 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: 1153 Lines: 32 With this change, we no longer lose the innermost entry in the user-mode part of the call chain. See also the x86 port, which includes the ip. It's possible to partially work around this problem by post-processing the data to use the PERF_SAMPLE_IP value, but this works only if the CPU wasn't in the kernel when the sample was taken. Signed-off-by: Jed Davis --- arch/arm/kernel/perf_event.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 8c3094d..d9f5cd4 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -569,6 +569,7 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) return; } + perf_callchain_store(entry, regs->ARM_pc); tail = (struct frame_tail __user *)regs->ARM_fp - 1; while ((entry->nr < PERF_MAX_STACK_DEPTH) && -- 1.7.10.4 -- 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/