Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756748AbbHZJ3s (ORCPT ); Wed, 26 Aug 2015 05:29:48 -0400 Received: from mail4.hitachi.co.jp ([133.145.228.5]:42467 "EHLO mail4.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753504AbbHZJ3q (ORCPT ); Wed, 26 Aug 2015 05:29:46 -0400 From: =?utf-8?B?5bmz5p2+6ZuF5bezIC8gSElSQU1BVFXvvIxNQVNBTUk=?= To: "'Wang Nan'" , "acme@kernel.org" , "rostedt@goodmis.org" CC: "mingo@redhat.com" , "namhyung@kernel.org" , "linux-kernel@vger.kernel.org" , "pi3orama@163.com" , sysp-manager Subject: RE: [PATCH v2 2/4] perf probe: Fix list result when address is zero Thread-Topic: [PATCH v2 2/4] perf probe: Fix list result when address is zero Thread-Index: AQHQ39KI+IK/hzaKY0OvkSuY48uJGZ4d+sJw Date: Wed, 26 Aug 2015 09:29:42 +0000 Message-ID: <50399556C9727B4D88A595C8584AAB37524EC6F0@GSjpTKYDCembx32.service.hitachi.net> References: <1440574825-221187-1-git-send-email-wangnan0@huawei.com> <1440574825-221187-3-git-send-email-wangnan0@huawei.com> In-Reply-To: <1440574825-221187-3-git-send-email-wangnan0@huawei.com> Accept-Language: ja-JP, en-US Content-Language: ja-JP X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.198.219.51] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id t7Q9TqFU024005 Content-Length: 3426 Lines: 98 > From: Wang Nan [mailto:wangnan0@huawei.com] > > When manually added uprobe point with zero address, 'perf probe -l' > reports error. For example: > > # echo p:probe_libc/abs_0 /path/to/lib.bin:0x0 arg1=%ax > \ > /sys/kernel/debug/tracing/uprobe_events > > # perf probe -l > Error: Failed to show event list. > > Probing at 0x0 is possible and useful when lib.bin is not a normal > shared object but is manually mapped. However, in this case kernel > report: > > # cat /sys/kernel/debug/tracing/uprobe_events > p:probe_libc/abs_0 /tmp/oxygen_root/lib64/libc-2.18.so:0x (null) arg1=%ax > > This patch supports the above kernel output. Former part is OK to me. > > In addition, this patch also fixes convert_to_perf_probe_point() that, > if failed to find probe point from both of dwarf and map, in all cases > pp->function should be filled with a strdup() result, or the following > ENOMEM error code is incorrect. Remove !tp->module && !is_kprobe > condition so always use address to build function name if symbol is not > found. No, I think this should be included in 3/4, since until that perf probe doesn't support absolute address on kernel. Thank you, > > Signed-off-by: Wang Nan > Cc: Arnaldo Carvalho de Melo > Cc: Ingo Molnar > Cc: Masami Hiramatsu > Cc: Namhyung Kim > Cc: Steven Rostedt > --- > tools/perf/util/probe-event.c | 30 ++++++++++++++++++++++++++---- > 1 file changed, 26 insertions(+), 4 deletions(-) > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index ef325a2..3ce223d 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -1521,9 +1521,31 @@ int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev) > } else > p = argv[1]; > fmt1_str = strtok_r(p, "+", &fmt); > - if (fmt1_str[0] == '0') /* only the address started with 0x */ > - tp->address = strtoul(fmt1_str, NULL, 0); > - else { > + /* only the address started with 0x */ > + if (fmt1_str[0] == '0') { > + /* > + * Fix a special case: > + * if address == 0, kernel reports something like: > + * p:probe_libc/abs_0 /lib/libc-2.18.so:0x (null) arg1=%ax > + * Newer kernel may fix that, but we want to > + * support old kernel also. > + */ > + if (strcmp(fmt1_str, "0x") == 0) { > + if (!argv[2] || strcmp(argv[2], "(null)")) { > + ret = -EINVAL; > + goto out; > + } > + tp->address = 0; > + > + free(argv[2]); > + for (i = 2; argv[i + 1] != NULL; i++) > + argv[i] = argv[i + 1]; > + > + argv[i] = NULL; > + argc -= 1; > + } else > + tp->address = strtoul(fmt1_str, NULL, 0); > + } else { > /* Only the symbol-based probe has offset */ > tp->symbol = strdup(fmt1_str); > if (tp->symbol == NULL) { > @@ -1868,7 +1890,7 @@ static int convert_to_perf_probe_point(struct probe_trace_point *tp, > if (tp->symbol) { > pp->function = strdup(tp->symbol); > pp->offset = tp->offset; > - } else if (!tp->module && !is_kprobe) { > + } else { > ret = e_snprintf(buf, 128, "0x%" PRIx64, (u64)tp->address); > if (ret < 0) > return ret; > -- > 1.8.3.4 ????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?