kernel/tools/perf/Documentation/perf-probe.txt, branch linux-4.17.y

perf probe: Support escaped character in parser

2017-12-27T15:15:55Z

Support the special characters escaped by '\' in parser. This allows user to specify versions directly like below. ===== # ./perf probe -x /lib64/libc-2.25.so malloc_get_state\\@GLIBC_2.2.5 Added new event: probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc_get_state -aR sleep 1 ===== Or, you can use separators in source filename, e.g. ===== # ./perf probe -x /opt/test/a.out foo+bar.c:3 Semantic error :There is non-digit character in offset. Error: Command Parse Error. ===== Usually "+" in source file cause parser error, but ===== # ./perf probe -x /opt/test/a.out foo\\+bar.c:4 Added new event: probe_a:main (on @foo+bar.c:4 in /opt/test/a.out) You can now use it in all perf tools, such as: perf record -e probe_a:main -aR sleep 1 ===== escaped "\+" allows you to specify that. Signed-off-by: Masami Hiramatsu Reviewed-by: Thomas Richter Acked-by: Ravi Bangoria Cc: Paul Clarke Cc: bhargavb Cc: linux-rt-users@vger.kernel.org Link: http://lkml.kernel.org/r/151309111236.18107.5634753157435343410.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Add __return suffix for return events

2017-12-27T15:15:54Z

Add __return suffix for function return events automatically. Without this, user have to give --force option and will see the number suffix for each event like "function_1", which is not easy to recognize. Instead, this adds __return suffix to it automatically. E.g. ===== # ./perf probe -x /lib64/libc-2.25.so 'malloc*%return' Added new events: probe_libc:malloc_printerr__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_consolidate__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_check__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_hook_ini__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_trim__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_usable_size__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_stats__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_info__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:mallochook__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_get_state__return (on malloc*%return in /usr/lib64/libc-2.25.so) probe_libc:malloc_set_state__return (on malloc*%return in /usr/lib64/libc-2.25.so) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc_set_state__return -aR sleep 1 ===== Reported-by: Arnaldo Carvalho de Melo Signed-off-by: Masami Hiramatsu Acked-by: Ravi Bangoria Reviewed-by: Thomas Richter Tested-by: Arnaldo Carvalho de Melo Cc: Paul Clarke Cc: bhargavb Cc: linux-rt-users@vger.kernel.org Link: http://lkml.kernel.org/r/151275046418.24652.6696011972866498489.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

perf buildid-cache: Support binary objects from other namespaces

2017-07-19T02:14:11Z

Teach buildid-cache how to add, remove, and update binary objects from other mount namespaces. Allow probe events tracing binaries in different namespaces to add their objects to the probe and build-id caches too. As a handy side effect, this also lets us access SDT probes in binaries from alternate mount namespaces. Signed-off-by: Krister Johansen Tested-by: Brendan Gregg Cc: Alexander Shishkin Cc: Peter Zijlstra Cc: Thomas-Mich Richter Link: http://lkml.kernel.org/r/1499305693-1599-5-git-send-email-kjlx@templeofstupid.com [ Add util/namespaces.c to tools/perf/util/python-ext-sources, to fix the python binding 'perf test' ] Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Allow placing uprobes in alternate namespaces.

2017-07-19T02:14:10Z

Teaches perf how to place a uprobe on a file that's in a different mount namespace. The user must add the probe using the --target-ns argument to perf probe. Once it has been placed, it may be recorded against without further namespace-specific commands. Signed-off-by: Krister Johansen Cc: Alexander Shishkin Cc: Brendan Gregg Cc: Peter Zijlstra Cc: Ravi Bangoria [ PPC build fixed by Ravi: ] Link: http://lkml.kernel.org/r/1500287542-6219-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com Cc: Thomas-Mich Richter [ Fix !HAVE_DWARF_SUPPORT build ] Link: http://lkml.kernel.org/r/1499305693-1599-4-git-send-email-kjlx@templeofstupid.com Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Fix examples section of documentation

2017-06-07T23:23:11Z

An example in perf-probe documentation for pattern of function name based probe addition is not providing example command for that case. This commit fixes the example to give appropriate example command. Signed-off-by: SeongJae Park Acked-by: Masami Hiramatsu Cc: Peter Zijlstra Cc: Taeung Song Fixes: ee391de876ae ("perf probe: Update perf probe document") Link: http://lkml.kernel.org/r/20170507103642.30560-1-sj38.park@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Ignore vmlinux buildid if offline kernel is given

2016-09-01T12:44:14Z

Ignore the buildid of running kernel when both of --definition and --vmlinux is given because that kernel should be off-line. This also skips post-processing of kprobe event for relocating symbol and checking blacklist, because it can not be done on off-line kernel. E.g. without this fix perf shows an error as below ---- $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open ./vmlinux-arm with build id 7a1f76dd56e9c4da707cd3d6333f50748141434b not found, continuing without symbols Failed to find symbol do_sys_open in kernel Error: Failed to add events. ---- with this fix, we can get the definition ---- $ perf probe --vmlinux=./vmlinux-arm --definition do_sys_open p:probe/do_sys_open do_sys_open+0 ---- Signed-off-by: Masami Hiramatsu Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/147214228193.23638.12581984840822162131.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Show trace event definition

2016-09-01T12:44:13Z

Add --definition/-D option for showing the trace-event definition in stdout. This can be useful in debugging or combined with a shell script. e.g. ---- # perf probe --definition 'do_sys_open $params' p:probe/do_sys_open _text+2261728 dfd=%di:s32 filename=%si:u64 flags=%dx:s32 mode=%cx:u16 ---- Suggested-and-Tested-by: Arnaldo Carvalho de Melo Signed-off-by: Masami Hiramatsu Cc: Ingo Molnar Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/147214226712.23638.2240534040014013658.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

ftrace: kprobe: uprobe: Show u8/u16/u32/u64 types in decimal

2016-08-23T20:06:38Z

Change kprobe/uprobe-tracer to show the arguments type-casted with u8/u16/u32/u64 in decimal digits instead of hexadecimal. To minimize compatibility issue, the arguments without type casting are typed by x64 (or x32 for 32bit arch) by default. Note: all arguments set by old perf probe without types are shown in decimal by default. Signed-off-by: Masami Hiramatsu Acked-by: Steven Rostedt Cc: Alexander Shishkin Cc: Hemant Kumar Cc: Naohiro Aota Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/147151076135.12957.14684546093034343894.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Support hexadecimal casting

2016-08-23T20:06:37Z

Support hexadecimal unsigned integer casting by 'x'. This allows user to explicitly specify the output format of the probe arguments as hexadecimal. Signed-off-by: Masami Hiramatsu Cc: Alexander Shishkin Cc: Hemant Kumar Cc: Naohiro Aota Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Wang Nan Link: http://lkml.kernel.org/r/147151072679.12957.4458656416765710753.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo

ftrace: kprobe: uprobe: Add x8/x16/x32/x64 for hexadecimal types

2016-08-23T18:38:09Z

Add x8/x16/x32/x64 for hexadecimal type casting to kprobe/uprobe event tracer. These type casts can be used for integer arguments for explicitly showing them in hexadecimal digits in formatted text. Signed-off-by: Masami Hiramatsu Acked-by: Steven Rostedt Cc: Alexander Shishkin Cc: Hemant Kumar Cc: Naohiro Aota Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/147151067029.12957.11591314629326414783.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo