From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S942560AbcJFQOn (ORCPT ); Thu, 6 Oct 2016 12:14:43 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:59002 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S942293AbcJFQMJ (ORCPT ); Thu, 6 Oct 2016 12:12:09 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Linux Weekly News , Ravi Bangoria , Alexander Shishkin , Balbir Singh , Masami Hiramatsu , "Naveen N . Rao" , Peter Zijlstra , Arnaldo Carvalho de Melo Subject: [PATCH 01/13] perf uretprobe ppc64le: Fix probe location Date: Thu, 6 Oct 2016 13:11:44 -0300 Message-Id: <1475770316-20057-2-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1475770316-20057-1-git-send-email-acme@kernel.org> References: <1475770316-20057-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ravi Bangoria Perf uretprobe probes on GEP(Global Entry Point) which fails to record all function calls via LEP(Local Entry Point). Fix that by probing on LEP. Objdump: 00000000100005f0 : 100005f0: 02 10 40 3c lis r2,4098 100005f4: 00 7f 42 38 addi r2,r2,32512 100005f8: a6 02 08 7c mflr r0 100005fc: 10 00 01 f8 std r0,16(r1) 10000600: f8 ff e1 fb std r31,-8(r1) Before applying patch: $ cat /sys/kernel/debug/tracing/uprobe_events r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f0 After applying patch: $ cat /sys/kernel/debug/tracing/uprobe_events r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f8 This is not the case with kretprobes because the kernel itself finds LEP and probes on it. Signed-off-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Balbir Singh Cc: Masami Hiramatsu Cc: Naveen N. Rao Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1475576865-6562-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/powerpc/util/sym-handling.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c index ed9d5d15d5b6..1030a6e504bb 100644 --- a/tools/perf/arch/powerpc/util/sym-handling.c +++ b/tools/perf/arch/powerpc/util/sym-handling.c @@ -82,7 +82,8 @@ void arch__fix_tev_from_maps(struct perf_probe_event *pev, * * In addition, we shouldn't specify an offset for kretprobes. */ - if (pev->point.offset || pev->point.retprobe || !map || !sym) + if (pev->point.offset || (!pev->uprobes && pev->point.retprobe) || + !map || !sym) return; lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym); -- 2.7.4