From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754252AbbCXQZf (ORCPT ); Tue, 24 Mar 2015 12:25:35 -0400 Received: from mail.kernel.org ([198.145.29.136]:59428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754271AbbCXQUZ (ORCPT ); Tue, 24 Mar 2015 12:20:25 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Masami Hiramatsu , He Kuang , Namhyung Kim , Peter Zijlstra , Wang Nan , Arnaldo Carvalho de Melo Subject: [PATCH 09/25] perf probe: Fix to get ummapped symbol address on kernel Date: Tue, 24 Mar 2015 13:19:24 -0300 Message-Id: <1427213980-9015-10-git-send-email-acme@kernel.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1427213980-9015-1-git-send-email-acme@kernel.org> References: <1427213980-9015-1-git-send-email-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masami Hiramatsu Fix to get correctly unmapped symbol address on kernel. This allows us to probe on syscall symbols which are aliases of SyS_ functions with using debuginfo. Without this fix: ---- # ./perf probe -a sys_write Failed to find debug information for address 3b0100 Probe point 'sys_write' not found. Error: Failed to add events. ---- The address 0x3b0100 is a mapped address, and not usable in debuginfo. With this fix: ---- # ./perf probe -a sys_write Added new event: probe:sys_write (on sys_write) You can now use it in all perf tools, such as: perf record -e probe:sys_write -aR sleep 1 ---- Signed-off-by: Masami Hiramatsu Cc: He Kuang Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/20150322114022.32639.19096.stgit@localhost.localdomain Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 6b95985db5b0..8feac0774c41 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -310,7 +310,10 @@ static int find_alternative_probe_point(struct debuginfo *dinfo, /* Find the address of given function */ map__for_each_symbol_by_name(map, pp->function, sym) { - address = sym->start; + if (uprobes) + address = sym->start; + else + address = map->unmap_ip(map, sym->start); break; } if (!address) { -- 1.9.3