From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754773AbbCSKHA (ORCPT ); Thu, 19 Mar 2015 06:07:00 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:30565 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754602AbbCSKG7 (ORCPT ); Thu, 19 Mar 2015 06:06:59 -0400 From: He Kuang To: , , , , CC: , Subject: [PATCH] perf probe: Fix failure to add multiple probes without debuginfo Date: Thu, 19 Mar 2015 18:02:04 +0800 Message-ID: <1426759324-32538-1-git-send-email-hekuang@huawei.com> X-Mailer: git-send-email 2.3.3.220.g9ab698f In-Reply-To: <1426757023-14290-1-git-send-email-hekuang@huawei.com> References: <1426757023-14290-1-git-send-email-hekuang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.189] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Perf tries to find probe function addresses from map when debuginfo could not be found. To the first added function, the value of ref_reloc_sym was set in maps__set_kallsyms_ref_reloc_sym() and can be obtained from host_machine->kmaps->maps. After that, new maps are added to host_machine->kmaps->maps in dso__load_kcore(), all these new added maps do not have a valid ref_reloc_sym. When adding a second function, get_target_map() may get a map without valid ref_reloc_sym, and raise the error "Relocated base symbol is not found". Fix this by getting ref_reloc_sym from machine->vmlinux_maps. This problem can be reproduced as following: $ perf probe --add='sys_write' --add='sys_open' Relocated base symbol is not found! Error: Failed to add events. After this patch: $ perf probe --add='sys_write' --add='sys_open' 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 Added new event: probe:sys_open (on sys_open) You can now use it in all perf tools, such as: perf record -e probe:sys_open -aR sleep 1 Signed-off-by: He Kuang --- tools/perf/util/probe-event.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index c5e1338..75d41ee 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -2540,7 +2540,19 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, } if (!pev->uprobes && !pp->retprobe) { - kmap = map__kmap(map); + struct machine *machine; + struct map *vmlinux_map = NULL; + + if (map->groups && map->groups->machine) { + machine = map->groups->machine; + vmlinux_map = machine->vmlinux_maps[MAP__FUNCTION]; + } + + if (vmlinux_map) + kmap = map__kmap(vmlinux_map); + else + kmap = map__kmap(map); + reloc_sym = kmap->ref_reloc_sym; if (!reloc_sym) { pr_warning("Relocated base symbol is not found!\n"); -- 2.3.3.220.g9ab698f