Commit Graph

283 Commits

Author SHA1 Message Date
Masami Hiramatsu
2a12ec13cc perf probe: Set default kprobe group name if it is not given
Set kprobe group name as "probe" if it is not given.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426090413.11891.95640.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-26 13:14:58 -03:00
Masami Hiramatsu
062d6c2aec perf probe: Close target file on error path
Fix a bug to close target elf file in get_text_start_address().

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20160426064737.1443.44093.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-26 10:56:08 -03:00
Arnaldo Carvalho de Melo
88fd633cdf perf probe: No need to use formatting strbuf method
We have addch() for chars, add() for fixed size data, and addstr() for
variable length strings, use them.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-0ap02fn2xtvpduj2j6b2o1j4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-03-23 16:53:05 -03:00
Wang Nan
03e01f5687 perf bpf: Allow BPF program config probing options
By extending the syntax of BPF object section names, this patch allows users to
config probing options like what they can do in 'perf probe'.

The error message in 'perf probe' is also updated.

Test result:

For following BPF file test_probe_glob.c:

  # cat test_probe_glob.c
  __attribute__((section("inlines=no;func=SyS_dup?"), used))

  int func(void *ctx)
  {
	  return 1;
  }

  char _license[] __attribute__((section("license"), used)) = "GPL";
  int _version __attribute__((section("version"), used)) = 0x40300;
  #
  # ./perf record  -e ./test_probe_glob.c ls /
  ...
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data ]
  # ./perf evlist
  perf_bpf_probe:func_1
  perf_bpf_probe:func

After changing "inlines=no" to "inlines=yes":

  # ./perf record  -e ./test_probe_glob.c ls /
  ...
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data ]
  # ./perf evlist
  perf_bpf_probe:func_3
  perf_bpf_probe:func_2
  perf_bpf_probe:func_1
  perf_bpf_probe:func

Then test 'force':

Use following program:

  # cat test_probe_force.c
  __attribute__((section("func=sys_write"), used))

  int funca(void *ctx)
  {
	  return 1;
  }

  __attribute__((section("force=yes;func=sys_write"), used))

  int funcb(void *ctx)
  {
  	return 1;
  }

  char _license[] __attribute__((section("license"), used)) = "GPL";
  int _version __attribute__((section("version"), used)) = 0x40300;
  #

  # perf record -e ./test_probe_force.c usleep 1
  Error: event "func" already exists.
   Hint: Remove existing event by 'perf probe -d'
       or force duplicates by 'perf probe -f'
       or set 'force=yes' in BPF source.
  event syntax error: './test_probe_force.c'
                       \___ Probe point exist. Try 'perf probe -d "*"' and set 'force=yes'

  (add -v to see detail)
  ...

Then replace 'force=no' to 'force=yes':

  # vim test_probe_force.c
  # perf record -e ./test_probe_force.c usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data ]
  # perf evlist
  perf_bpf_probe:func_1
  perf_bpf_probe:func
  #

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1447675815-166222-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-18 17:51:04 -03:00
Masami Hiramatsu
0a62f6869f perf probe: Cleanup find_perf_probe_point_from_map to reduce redundancy
In find_perf_probe_point_from_map(), the 'ret' variable is initialized
with -ENOENT but overwritten by the return code of
kernel_get_symbol_address_by_name(), and after that it is re-initialized
with -ENOENT again.

Setting ret=-ENOENT twice looks a bit redundant. This avoids the
overwriting and just returns -ENOENT if some error happens to simplify
the code.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/n/tip-ufp1zgbktzmttcputozneomd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-06 10:47:33 -03:00
Wang Nan
98d3b258ed perf tools: Fix find_perf_probe_point_from_map() which incorrectly returns success
It is possible that find_perf_probe_point_from_map() fails to find a
symbol but still returns 0 because of an small error when coding:
find_perf_probe_point_from_map() set 'ret' to error code at first, but
also use it to hold return value of kernel_get_symbol_address_by_name().

This patch resets 'ret' to error even kernel_get_symbol_address_by_name()
success, so if !sym, the whole function returns error correctly.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1446729565-27592-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 12:47:52 -03:00
Masami Hiramatsu
1a8ac29cbf perf probe: Allow probing on kmodules without dwarf
Allow probing on kernel modules when 'perf' is built without debuginfo
support.

Currently perf-probe --module requires linking with libdw, but this
doesn't make sense.

E.g.
  ----
  # make NO_DWARF=1
  # ./perf probe -m pcspkr pcspkr_event%return
    Error: unknown switch `m'
  ----

With this patch
  ----
  # ./perf probe -m pcspkr pcspkr_event%return
  Added new event:
    probe:pcspkr_event   (on pcspkr_event%return in pcspkr)

  You can now use it in all perf tools, such as:

          perf record -e probe:pcspkr_event -aR sleep 1
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20151002125832.18617.78721.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-10-02 15:59:23 -03:00
Masami Hiramatsu
20f49859c7 perf probe: Fix a segfault bug in debuginfo_cache
perf probe --list will get a segfault if the first kprobe event is on a
module and the second or latter one is on the kernel.

e.g.
  ----
  # ./perf probe -q -m pcspkr pcspkr_event
  # ./perf probe -q vfs_read
  # ./perf probe -l
  Segmentation fault (core dumped)
  ----

This is because the debuginfo_cache fails to handle NULL module name,
which causes segfault on strcmp. (Note that strcmp("something", NULL)
always causes segfault)

To fix this debuginfo_cache__open always translates the NULL module name
to "kernel" (this is correct, because NULL module name means opening the
debuginfo for the kernel)

  ----
  # ./perf probe -l
    probe:pcspkr_event   (on pcspkr_event@drivers/input/misc/pcspkr.c
    in pcspkr)
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164135.3733.23993.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30 18:34:36 -03:00
Masami Hiramatsu
9b239a12bc perf probe: Show correct source lines of probes on kmodules
Perf probe always failed to find appropriate line numbers because of
failing to find .text start address offset from debuginfo.

e.g.
  ----
  # ./perf probe -m pcspkr pcspkr_event:5
  Added new events:
    probe:pcspkr_event   (on pcspkr_event:5 in pcspkr)
    probe:pcspkr_event_1 (on pcspkr_event:5 in pcspkr)

  You can now use it in all perf tools, such as:

          perf record -e probe:pcspkr_event_1 -aR sleep 1

  # ./perf probe -l
  Failed to find debug information for address ffffffffa031f006
  Failed to find debug information for address ffffffffa031f016
    probe:pcspkr_event   (on pcspkr_event+6 in pcspkr)
    probe:pcspkr_event_1 (on pcspkr_event+22 in pcspkr)
  ----

This fixes the above issue as below.
1. Get the relative address of the symbol in .text by using
   map->start.
2. Adjust the address by adding the offset of .text section
   in the kernel module binary.

With this fix, perf probe -l shows lines correctly.
  ----
  # ./perf probe -l
    probe:pcspkr_event   (on pcspkr_event:5@drivers/input/misc/pcspkr.c in pcspkr)
    probe:pcspkr_event_1 (on pcspkr_event:5@drivers/input/misc/pcspkr.c in pcspkr)
  ----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164132.3733.24643.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30 18:34:35 -03:00
Masami Hiramatsu
663b1151f2 perf probe: Fix to remove dot suffix from second or latter events
Fix to remove dot suffix (e.g. .const, .isra) from the second or latter
events which has suffix numbers.

Since the previous commit 35a23ff928 ("perf probe: Cut off the gcc
optimization postfixes from function name") didn't care about the suffix
numbered events, therefore we'll have an error when we add additional
events on the same dot suffix functions.

e.g.
  ----
  # ./perf probe -f -a get_sigframe.isra.2.constprop.3 \
   -a get_sigframe.isra.2.constprop.3
  Failed to write event: Invalid argument
    Error: Failed to add events.
  ----

This fixes above issue as below:
  ----
  # ./perf probe -f -a get_sigframe.isra.2.constprop.3 \
   -a get_sigframe.isra.2.constprop.3
  Added new events:
    probe:get_sigframe   (on get_sigframe.isra.2.constprop.3)
    probe:get_sigframe_1 (on get_sigframe.isra.2.constprop.3)

  You can now use it in all perf tools, such as:

          perf record -e probe:get_sigframe_1 -aR sleep 1

  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164130.3733.26573.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30 18:34:33 -03:00
Arnaldo Carvalho de Melo
a5e813c686 perf machine: Add method for common kernel_map(FUNCTION) operation
And it is also a step in the direction of killing the separation of data
and text maps in map_groups.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-rrds86kb3wx5wk8v38v56gw8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30 18:34:29 -03:00
Arnaldo Carvalho de Melo
77e6597749 perf machine: Use machine__kernel_map() thoroughly
In places where we were using its open coded equivalent.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-khkdugcdoqy3tkszm3jdxgbe@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30 18:34:28 -03:00
Ingo Molnar
6afc0c269c Merge branch 'linus' into perf/core, to pick up fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-09-28 08:06:57 +02:00
Arnaldo Carvalho de Melo
266fa2b222 perf probe: Use existing routine to look for a kernel module by dso->short_name
We have map_groups__find_by_name() to look at the list of modules that
are in place for a given machine, so use it instead of traversing the
machine dso list, which also includes DSOs for userspace.

When merging the user and kernel DSO lists a bug was introduced where
'perf probe' stopped being able to add probes to modules using its short
name:

  # perf probe -m usbnet --add usbnet_start_xmit
  usbnet_start_xmit is out of .text, skip it.
    Error: Failed to add events.
  #

With this fix it works again:

  # perf probe -m usbnet --add usbnet_start_xmit
  Added new event:
    probe:usbnet_start_xmit (on usbnet_start_xmit in usbnet)

  You can now use it in all perf tools, such as:

  	perf record -e probe:usbnet_start_xmit -aR sleep 1
  #

Reported-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: 3d39ac5386 ("perf machine: No need to have two DSOs lists")
Link: http://lkml.kernel.org/r/20150924015008.GE1897@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-25 10:41:31 -03:00
Namhyung Kim
9bae1e8c3f perf probe: Export init/exit_probe_symbol_maps()
The init/exit_symbols_maps() functions are to setup and cleanup
necessary info for probe events.  But they need to be called from out of
the probe code now, so this patch exports them.

However the names are too generic, so change them to have 'probe'. :)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1441852026-28974-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-15 09:48:32 -03:00
Namhyung Kim
a43aac299c perf probe: Free perf_probe_event in cleanup_perf_probe_events()
The cleanup_perf_probe_events() frees all resources related to a perf
probe event.  However it only freed resources in trace probe events, not
perf probe events.  So call clear_perf_probe_event() too.

Reported-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1441852026-28974-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-15 09:48:32 -03:00
Jiri Olsa
4605eab348 tools lib api fs: Replace debugfs/tracefs objects interface with fs.c
Switching to the fs.c related filesystem framework.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Raphael Beamonte <raphael.beamonte@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1441180605-24737-14-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-14 12:50:15 -03:00
Namhyung Kim
e607f1426b perf probe: Print deleted events in cmd_probe()
Showing actual trace event when deleteing perf events is only needed in
perf probe command.  But the add functionality itself can be used by
other places.  So move the printing code into the cmd_probe().

The output is not changed.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-5-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-04 12:43:44 -03:00
Namhyung Kim
b02137cc65 perf probe: Move print logic into cmd_probe()
Showing actual trace event when adding perf events is only needed in
perf probe command.  But the add functionality itself can be used by
other places.  So move the printing code into the cmd_probe().

Also it combines the output if more than one event is added.

Before:
  $ sudo perf probe -a do_fork -a do_exit
  Added new event:
  probe:do_fork        (on do_fork)

  You can now use it in all perf tools, such as:

      perf record -e probe:do_fork -aR sleep 1

  Added new events:
  probe:do_exit        (on do_exit)
  probe:do_exit_1      (on do_exit)

  You can now use it in all perf tools, such as:

      perf record -e probe:do_exit_1 -aR sleep 1

After:
  $ sudo perf probe -a do_fork -a do_exit
  Added new events:
  probe:do_fork        (on do_fork)
  probe:do_exit        (on do_exit)
  probe:do_exit_1      (on do_exit)

  You can now use it in all perf tools, such as:

      perf record -e probe:do_exit_1 -aR sleep 1

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-3-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-04 12:37:17 -03:00
Wang Nan
12fae5ef6d perf probe: Link trace_probe_event into perf_probe_event
This patch drops struct __event_package structure.  Instead, it adds a
'struct trace_probe_event' pointer to 'struct perf_probe_event'.

The trace_probe_event information gives further patches a chance to
access actual probe points and actual arguments.

Using them, 'perf probe' can get the whole list of added probes and
print them at once.

Other users like the upcoming bpf_loader will be able to attach one bpf
program to different probing points of an inline function (which has
multiple probing points) and glob functions.

Moreover, by reading the arguments information, bpf code for reading
those arguments can be generated.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-2-git-send-email-namhyung@kernel.org
[namhyung: extract necessary part from the existing patch]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-04 12:34:23 -03:00
Namhyung Kim
844dffa598 perf probe: Split add_perf_probe_events()
The add_perf_probe_events() does 3 things:

 1. convert all perf events to trace events
 2. add all trace events to kernel
 3. cleanup all trace events

But sometimes we need to do something with the trace events.  So split
the funtion into three, so that it can access intermediate trace events
via struct __event_package if needed.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1441368963-11565-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-04 12:33:02 -03:00
Wang Nan
da15bd9df4 perf probe: Support probing at absolute address
It should be useful to allow 'perf probe' probe at absolute offset of a
target. For example, when (u)probing at a instruction of a shared object
in a embedded system where debuginfo is not avaliable but we know the
offset of that instruction by manually digging.

This patch enables following perf probe command syntax:

  # perf probe 0xffffffff811e6615

And

  # perf probe /lib/x86_64-linux-gnu/libc-2.19.so 0xeb860

In the above example, we don't need a anchor symbol, so it is possible
to compute absolute addresses using other methods and then use 'perf
probe' to create the probing points.

v1 -> v2:
  Drop the leading '+' in cmdline;
  Allow uprobing at offset 0x0;
  Improve 'perf probe -l' result when uprobe at area without debuginfo.

v2 -> v3:
  Split bugfix to a separated patch.

Test result:

  # perf probe 0xffffffff8119d175 %ax
  # perf probe sys_write %ax
  # perf probe /lib64/libc-2.18.so 0x0 %ax
  # perf probe /lib64/libc-2.18.so 0x5 %ax
  # perf probe /lib64/libc-2.18.so 0xd8e40 %ax
  # perf probe /lib64/libc-2.18.so __write %ax
  # perf probe /lib64/libc-2.18.so 0xd8e49 %ax
  # cat /sys/kernel/debug/tracing/uprobe_events

  p:probe_libc/abs_0 /lib64/libc-2.18.so:0x          (null) arg1=%ax
  p:probe_libc/abs_5 /lib64/libc-2.18.so:0x0000000000000005 arg1=%ax
  p:probe_libc/abs_d8e40 /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
  p:probe_libc/__write /lib64/libc-2.18.so:0x00000000000d8e40 arg1=%ax
  p:probe_libc/abs_d8e49 /lib64/libc-2.18.so:0x00000000000d8e49 arg1=%ax

  # cat /sys/kernel/debug/tracing/kprobe_events

  p:probe/abs_ffffffff8119d175 0xffffffff8119d175 arg1=%ax
  p:probe/sys_write _text+1692016 arg1=%ax

  # perf probe -l

  Failed to find debug information for address 5
    probe:abs_ffffffff8119d175 (on sys_write+5 with arg1)
    probe:sys_write      (on sys_write with arg1)
    probe_libc:__write   (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
    probe_libc:abs_0     (on 0x0 in /lib64/libc-2.18.so with arg1)
    probe_libc:abs_5     (on 0x5 in /lib64/libc-2.18.so with arg1)
    probe_libc:abs_d8e40 (on @unix/syscall-template.S:81 in /lib64/libc-2.18.so with arg1)
    probe_libc:abs_d8e49 (on __GI___libc_write+9 in /lib64/libc-2.18.so with arg1)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:41:12 -03:00
Wang Nan
6c6e024f0a perf probe: Fix error reported when offset without function
This patch fixes a bug that, when offset is provided but function is
lost, parse_perf_probe_point() will give a "" string as function name,
so the checking code at the end of parse_perf_probe_point() become
useless.  For example:

  # perf probe +0x1234
  Failed to find symbol  in kernel
    Error: Failed to add events.

After this patch:

  # perf probe +0x1234
  Semantic error :Offset requires an entry function.
    Error: Command Parse Error.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-6-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:40:34 -03:00
Wang Nan
be07afe92a perf probe: Fix list result when address is zero
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 /path/to/lib.bin:0x          (null) arg1=%ax

This patch supports the above kernel output.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-5-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:39:20 -03:00
Wang Nan
614e2fdbd7 perf probe: Fix list result when symbol can't be found
'perf probe -l' reports error if it is unable find symbol through
address. Here is an example.

  # echo 'p:probe_libc/abs_5 /lib64/libc.so.6:0x5' >
          /sys/kernel/debug/tracing/uprobe_events
  # cat /sys/kernel/debug/tracing/uprobe_events
   p:probe_libc/abs_5 /lib64/libc.so.6:0x0000000000000005
  # perf probe -l
    Error: Failed to show event list

Also, this situation triggers a logical inconsistency in
convert_to_perf_probe_point() that, it returns ENOMEM but actually it
never try strdup().

This patch removes !tp->module && !is_kprobe condition, so it always
uses address to build function name if symbol not found.

Test result:

  # perf probe -l
    probe_libc:abs_5     (on 0x5 in /lib64/libc.so.6)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440586666-235233-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:36:04 -03:00
Wang Nan
e486367f01 perf probe: Prevent segfault when reading probe point with absolute address
'perf probe -l' panic if there is a manually inserted probing point with
absolute address. For example:

  # echo 'p:probe/abs_ffffffff811e6615 0xffffffff811e6615' > /sys/kernel/debug/tracing/kprobe_events
  # perf probe -l
  Segmentation fault (core dumped)

This patch fix this problem by considering the situation that
"tp->symbol == NULL" in find_perf_probe_point_from_dwarf() and
find_perf_probe_point_from_map().

After this patch:

  # perf probe -l
  probe:abs_ffffffff811e6615 (on SyS_write+5@fs/read_write.c)

And when debug info is missing:

  # rm -rf ~/.debug
  # mv /lib/modules/4.2.0-rc1+/build/vmlinux /lib/modules/4.2.0-rc1+/build/vmlinux.bak
  # perf probe -l
  probe:abs_ffffffff811e6615 (on sys_write+5)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440509256-193590-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-26 10:34:11 -03:00
Wang Nan
1c0bd0e891 perf probe: Try to use symbol table if searching debug info failed
A problem can occur in a statically linked perf when vmlinux can be found:

 # perf probe --add sys_epoll_pwait
 probe-definition(0): sys_epoll_pwait
 symbol:sys_epoll_pwait file:(null) line:0 offset:0 return:0 lazy:(null)
 0 arguments
 Looking at the vmlinux_path (7 entries long)
 Using /lib/modules/4.2.0-rc1+/build/vmlinux for symbols
 Open Debuginfo file: /lib/modules/4.2.0-rc1+/build/vmlinux
 Try to find probe point from debuginfo.
 Symbol sys_epoll_pwait address found : ffffffff8122bd40
 Matched function: SyS_epoll_pwait
 Failed to get call frame on 0xffffffff8122bd40
 An error occurred in debuginfo analysis (-2).
   Error: Failed to add events. Reason: No such file or directory (Code: -2)

The reason is caused by libdw that, if libdw is statically linked, it
can't load libebl_{arch}.so reliable.

In this case it is still possible to get the address from
/proc/kalksyms.  However, perf tries that only when libdw returns
-EBADF.

This patch gives it another chance to utilize symbol table, even if
libdw returns an error code other than -EBADF.

After applying this patch:

 # perf probe -nv --add sys_epoll_pwait
 probe-definition(0): sys_epoll_pwait
 symbol:sys_epoll_pwait file:(null) line:0 offset:0 return:0 lazy:(null)
 0 arguments
 Looking at the vmlinux_path (7 entries long)
 Using /lib/modules/4.2.0-rc1+/build/vmlinux for symbols
 Open Debuginfo file: /lib/modules/4.2.0-rc1+/build/vmlinux
 Try to find probe point from debuginfo.
 Symbol sys_epoll_pwait address found : ffffffff8122bd40
 Matched function: SyS_epoll_pwait
 Failed to get call frame on 0xffffffff8122bd40
 An error occurred in debuginfo analysis (-2).
 Trying to use symbols.
 Opening /sys/kernel/debug/tracing/kprobe_events write=1
 Added new event:
 Writing event: p:probe/sys_epoll_pwait _text+2276672
   probe:sys_epoll_pwait (on sys_epoll_pwait)

 You can now use it in all perf tools, such as:

 	perf record -e probe:sys_epoll_pwait -aR sleep 1

Although libdw returns an error (Failed to get call frame), perf tries
symbol table and finally gets correct address.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440151770-129878-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-21 12:57:20 -03:00
Masami Hiramatsu
92f6c72e7a perf probe: Move ftrace probe-event operations to probe-file.c
Move ftrace probe-event operations to probe-file.c from probe-event.c.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20150715091407.8915.14316.stgit@localhost.localdomain
[ Fixed up strlist__new() calls wrt 4a77e2183f ("perf strlist: Make dupstr be the...") ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-07-20 17:49:49 -03:00
Masami Hiramatsu
a3c9de6280 perf probe: Simplify __add_probe_trace_events code
Simplify the __add_probe_trace_events() code by taking out the
probe_trace_event__set_name() and updating show_perf_probe_event()

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20150715091400.8915.85501.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-07-20 17:49:49 -03:00
Arnaldo Carvalho de Melo
4a77e2183f perf strlist: Make dupstr be the default and part of an extensible config parm
So that we can pass more info to strlist__new() without having to change
its function signature, just adding entries to the strlist_config struct
with sensible defaults for when those fields are not specified.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-5uaaler4931i0s9sedxjquhq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-07-20 12:13:34 -03:00
He Kuang
7c31bb8c95 perf probe: Fix failure to probe events on arm
Fix failure to probe events on arm, the problem was introduced by commit
5a51fcd1f3 ("perf probe: Skip kernel symbols which is out of .text").

For some architectures, the '_etext' label is not in the .text section
(in the .notes section for arm/arm64).  Labels out of the .text section
are not loaded as symbols and we get a zero value when looking up its
addresses, which causes all events to be wrongly skipped.

This patch skips checking the text address range when failing to get the
address of '_etext' and thus fixes the problem.

The problem can be reproduced on arm as follows:

  # perf probe --add='generic_perform_write'
  generic_perform_write+0 is out of .text, skip it.
  Probe point 'generic_perform_write' not found.
    Error: Failed to add events.

After this patch:

  # perf probe --add='generic_perform_write'
  Added new event:
    probe:generic_perform_write (on generic_perform_write)

  You can now use it in all perf tools, such as:

    perf record -e probe:generic_perform_write -aR sleep 1

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1434595750-129791-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-23 18:21:44 -03:00
Masami Hiramatsu
7737af010b perf probe: Speed up perf probe --list by caching debuginfo
Speed up the "perf probe --list" by caching the last used debuginfo.
perf probe --list always open and load debuginfo for each entry of probe
list. This takes very a long time.

E.g. with vfs_* events (total 96 probes)

  [root@localhost perf]# time  ./perf probe -l &> /dev/null

  real    0m25.376s
  user    0m24.381s
  sys     0m1.012s

To solve this issue, this adds debuginfo_cache to cache the
last used debuginfo on memory.

With this fix, the perf-probe --list significantly improves
its speed.

  [root@localhost perf]#  time  ./perf probe -l &> /dev/null

  real    0m0.161s
  user    0m0.136s
  sys     0m0.025s

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150617145854.19715.15314.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-17 16:37:53 -03:00
Masami Hiramatsu
d350bd571f perf probe: Show usage even if the last event is skipped
When the last part of converted events are blacklisted or out-of-text,
those are skipped and perf probe doesn't show usage examples.  This
fixes it to show the example even if the last part of event list is
skipped.

E.g. without this patch, events are added, but suddenly end:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
    probe:vfs_open       (on vfs_*)
  ...
    probe:vfs_dentry_acceptable (on vfs_*)
    probe:vfs_load_quota_inode (on vfs_*)
  #

With this fix:

  # perf probe vfs_*
  vfs_caches_init_early is out of .text, skip it.
  vfs_caches_init is out of .text, skip it.
  Added new events:
    probe:vfs_fallocate  (on vfs_*)
  ...
    probe:vfs_load_quota_inode (on vfs_*)

  You can now use it in all perf tools, such as:

	perf record -e probe:vfs_load_quota_inode -aR sleep 1

Note that this can be reproduced ONLY IF the vfs_caches_init* is the
last part of matched symbol list. I've checked this happens on
"3.19.0-generic #18-Ubuntu" kernel binary.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115057.19906.5502.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-17 16:31:42 -03:00
Masami Hiramatsu
b031220d52 perf probe: Fix to return error if no probe is added
Fix perf probe to return an error if no probe is added due to the given
probe point being on the blacklist.

To fix this problem, this moves the blacklist checking to right after
finding symbols/probe-points and marks them as skipped.

If all the symbols are skipped, "perf probe"  returns an error as it
fails to find the corresponding probe address.

E.g. currently if a blacklisted probe is given:

  # perf probe do_trap && echo 'succeed'
  Added new event:
  Warning: Skipped probing on blacklisted function: sync_regs
  succeed

No! It must fail! With this patch, it correctly fails:

  # perf probe do_trap && echo 'succeed'
  do_trap is blacklisted function, skip it.
  Probe point 'do_trap' not found.
    Error: Failed to add events.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150616115055.19906.31359.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-16 11:39:51 -03:00
Masami Hiramatsu
ba7ecb02e7 perf probe: List probes in stdout
Since commit 5e17b28f1e ("perf probe: Add --quiet option to
suppress output result message") have replaced printf with pr_info,
perf probe -l outputs its result in stderr. However, that is not
what the commit expected.

E.g.:

  # perf probe -l > /dev/null
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)

With this fix:

  # perf probe -l > list
  # cat list
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)

Of course, --quiet(-q) still works on --add/--del.

  # perf probe -q vfs_write
  # perf probe -l
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
    probe:vfs_write      (on vfs_write@ksrc/linux-3/fs/read_write.c)
  -----

Reported-by: Naohiro Aota <naota@elisp.net>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150613013116.24402.2923.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-16 10:34:39 -03:00
Masami Hiramatsu
35a23ff928 perf probe: Cut off the gcc optimization postfixes from function name
Cut off the postfixes which gcc added for optimized routines from the
event name automatically generated from symbol name, since *probe-events
doesn't accept it.  Those symbols will be used if we don't use debuginfo
to find target functions.

E.g. without this fix;
  -----
  # perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf.isra.23 _text+4869328
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  -----
With this fix;
  -----
  perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf _text+4869328
    probe:alloc_buf      (on alloc_buf.isra.23)

  You can now use it in all perf tools, such as:

  	perf record -e probe:alloc_buf -aR sleep 1

  -----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150612050820.20548.41625.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-12 16:14:48 -03:00
Arnaldo Carvalho de Melo
9f2de31542 perf machine: Fix up some more method names
Calling the function 'machine__new_module' implies a new 'module' will
be allocated, when in fact what is returned is a 'struct map' instance,
that not necessarily will be instantiated, as if one already exists with
the given module name, it will be returned instead.

So be consistent with other "find and if not there, create" like
functions, like machine__findnew_thread, machine__findnew_dso, etc, and
rename it to machine__findnew_module_map(), that in turn will call
machine__findnew_module_dso().

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-acv830vd3hwww2ih5vjtbmu3@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-06-08 10:31:34 -03:00
Wang Nan
6bb536cc4b perf probe: Fix segfault when glob matching function without debuginfo
Commit 4c85935122 ("perf probe: Support
glob wildcards for function name") introduces segfault problems when
debuginfo is not available:

 # perf probe 'sys_w*'
  Added new events:
  Segmentation fault

The first problem resides in find_probe_trace_events_from_map(). In
that function, find_probe_functions() is called to match each symbol
against glob to find the number of matching functions, but still use
map__for_each_symbol_by_name() to find 'struct symbol' for matching
functions. Unfortunately, map__for_each_symbol_by_name() does
exact matching by searching in an rbtree.

It doesn't know glob matching, and not easy for it to support it because
it use rbtree based binary search, but we are unable to ensure all names
matched by the glob (any glob passed by user) reside in one subtree.

This patch drops map__for_each_symbol_by_name(). Since there is no
rbtree again, re-matching all symbols costs a lot. This patch avoid it
by saving all matching results into an array (syms).

The second problem is the lost of tp->realname. In
__add_probe_trace_events(), if pev->point.function is glob, the event
name should be set to tev->point.realname. This patch ensures its
existence by strdup sym->name instead of leaving a NULL pointer there.

After this patch:

 # perf probe 'sys_w*'
 Added new events:
   probe:sys_waitid     (on sys_w*)
   probe:sys_wait4      (on sys_w*)
   probe:sys_waitpid    (on sys_w*)
   probe:sys_write      (on sys_w*)
   probe:sys_writev     (on sys_w*)

 You can now use it in all perf tools, such as:

         perf record -e probe:sys_writev -aR sleep 1

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1432892747-232506-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-30 11:08:52 -03:00
Arnaldo Carvalho de Melo
3d39ac5386 perf machine: No need to have two DSOs lists
We can, given a DSO, figure out if it is a kernel, a kernel module or
a userlevel DSO, so stop having to process two lists in several
functions.

If searching becomes an issue at some point, we can have them in a
rbtree, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-s4yb0onpdywu6dj2xl9lxi4t@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-29 12:43:43 -03:00
Wang Nan
60fb774292 perf probe: Fix 'function unused' warning
By 'make build-test' a warning is found in probe-event.c that, after
commit 419e873828 (perf probe: Show the error reason comes from
invalid DSO) the only user of kernel_get_module_dso() is
open_debuginfo(). Which is not compiled if HAVE_DWARF_SUPPORT not set.

'make build-test' found this problem when make_minimal.

This patch moves kernel_get_module_dso() to HAVE_DWARF_SUPPORT ifdef
section.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1432779905-206143-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-29 12:43:39 -03:00
Arnaldo Carvalho de Melo
84c2cafa28 perf tools: Reference count struct map
We have pointers to struct map instances in several places, like in the
hist_entry instances, so we need a way to know when we can destroy them,
otherwise we may either keep leaking them or end up referencing deleted
instances.

Start fixing it by reference counting them.

This patch puts the reference count for struct map in place, replacing
direct map__delete() calls with map__put() ones and then grabbing a
reference count when adding it to the maps struct where maps for a
struct thread are kept.

Next we'll grab reference counts when setting pointers to struct map
instances, in places like in the hist_entry code.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-wi19xczk0t2a41r1i2chuio5@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 20:27:30 -03:00
Arnaldo Carvalho de Melo
1eee78aea9 perf tools: Introduce struct maps
That for now has the maps rbtree and the list for the dead maps, that
may be still referenced from some hist_entry, etc.

This paves the way for protecting the rbtree with a lock, then refcount
the maps and finally remove the removed_maps list, as it'll not ne
anymore needed.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-fl0fa6142pj8khj97fow3uw0@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 20:21:41 -03:00
Masami Hiramatsu
dddc7ee32f perf probe: Fix an error when deleting probes successfully
Fix a bug in del_perf_probe_events() which returns an error (-ENOENT)
even if the probes are successfully deleted.

This happens only if the probes are on user-apps and not on kernel,
simply because it doesn't clear the previous error.

So, without this fix, we get an error even though events are being
successfully removed.

  ------
  # ./perf probe -x ./perf del_perf_probe_events
  Added new event:
    probe_perf:del_perf_probe_events (on del_perf_probe_events in ...

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:del_perf_probe_events -aR sleep 1

  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
    Error: Failed to delete events.
  ------

This fixes the above error.
  ------
  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
  ------

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/20150527083725.23880.45209.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:46 -03:00
Masami Hiramatsu
419e873828 perf probe: Show the error reason comes from invalid DSO
Show the reason of error when dso__load* fails. This shows when user
gives wrong kernel image or wrong path.

Without this, perf probe shows an obscure message:

  ----
  $ perf probe -k ~/kbin/linux-3.x86_64/vmlinux -L vfs_read
  Failed to find path of kernel module.
    Error: Failed to show lines.
  ----

With this, perf shows appropriate error message:

  ----
  $ perf probe -k ~/kbin/linux-3.x86_64/vmlinux -L vfs_read
  Failed to find the path for kernel: Mismatching build id
    Error: Failed to show lines.
  ----

And:

  ----
  $ perf probe -k /non-exist/kernel/vmlinux -L vfs_read
  Failed to find the path for kernel: No such file or directory
    Error: Failed to show lines.
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Link: http://lkml.kernel.org/r/20150527083718.23880.84100.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Arnaldo Carvalho de Melo
4bb7123dcf perf tools: Use maps__first()/map__next()
In a few more remaining places, for consistency.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-c2n7slwtto29wndfttdrhfrx@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Arnaldo Carvalho de Melo
614c6b570d perf tools: Leave DSO destruction to the map destruction
As the way DSOs are created are normally via dsos__findnew, so that we
don't have to load the same dso multiple times for multiple maps (think
about /lib64/libc.so.6), so they may be shared and dso__delete() should
be left to be done as part of the map destruction process.

This will all be properly solved by reference counting struct dso, which
will be done soon.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-gbrohe1nvkjxw3u5a1bgj3yh@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-27 12:21:45 -03:00
Wang Nan
75e4a2a6af perf probe: Load map before glob matching
Commit 4c85935122 ("perf probe: Support
glob wildcards for function name") introduces a problem:

  # /root/perf probe kmem_cache_free
 Failed to find symbol kmem_cache_free in kernel
   Error: Failed to add events.

The reason is the replacement of map__for_each_symbol_by_name() (by
map__for_each_symbol()). Although their names are similar,
map__for_each_symbol doesn't call map__load() and dso__sort_by_name()
before searching. The missing of map__load() causes this problem because
it search symbol before load dso map.

This patch ensures map__load() is called before using
map__for_each_symbol().

After this patch:

 # /root/perf probe kmem_cache_free
  Added new event:
    probe:kmem_cache_free (on kmem_cache_free%return)

You can now use it in all perf tools, such as:

        perf record -e probe:kmem_cache_free -aR sleep 1

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1431692084-46287-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-18 10:16:48 -03:00
Ingo Molnar
f7dc7fd1c0 Merge branch 'perf/urgent' into perf/core, to resolve conflicts
Conflicts:
	tools/perf/builtin-kmem.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-11 11:56:27 +02:00
Masami Hiramatsu
4c85935122 perf probe: Support glob wildcards for function name
Support glob wildcards for function name when adding new probes. This
will allow us to build caches of function-entry level information with
$params.

e.g.
  ----
  # perf probe --no-inlines --add 'kmalloc* $params'
  Added new events:
    probe:kmalloc_slab   (on kmalloc* with $params)
    probe:kmalloc_large_node (on kmalloc* with $params)
    probe:kmalloc_order_trace (on kmalloc* with $params)

  You can now use it in all perf tools, such as:

        perf record -e probe:kmalloc_order_trace -aR sleep 1

  # perf probe --list
    probe:kmalloc_large_node (on kmalloc_large_node@mm/slub.c with size flags node)
    probe:kmalloc_order_trace (on kmalloc_order_trace@mm/slub.c with size flags order)
    probe:kmalloc_slab   (on kmalloc_slab@mm/slab_common.c with size flags)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010335.24812.19972.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:31:02 -03:00
Masami Hiramatsu
ddb2f58f9f perf probe: Introduce probe_conf global configs
Introduce probe_conf global configuration parameters for probe-event and
probe-finder, and removes related parameters from APIs.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010330.24812.21095.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:26:26 -03:00
Masami Hiramatsu
442255215c perf probe: Use perf_probe_event.target instead of passing as an argument
Use perf_probe_event.target field for the target binary instead of
passing it as an argument.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150508010328.24812.67887.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:25:21 -03:00
Masami Hiramatsu
5a51fcd1f3 perf probe: Skip kernel symbols which is out of .text
Skip the kernel symbols which is out of .text, e.g. the functions
in .inittext. Those are found in debuginfo/kallsyms, but already
freed from memory.

e.g.
  ----
  # perf probe vfs_caches_init
  vfs_caches_init+0 is out of .text, skip it.
  Probe point 'vfs_caches_init' not found.
    Error: Failed to add events.
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150506124649.4961.56249.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:02 -03:00
Masami Hiramatsu
573709fdfd perf probe: Make --line checks validate C-style function name
Fix --line to check valid C-style function name and returns
a semantic error if it is not.

For example, previously, --line doesn't support lazy pattern
but it doesn't recognized as a semantic error.

  ----
  # perf probe -L 'func;return*:0-10'
  Specified source line is not found.
    Error: Failed to show lines.
  ----

With this patch, it is correctly handled as a semantic error.
  ----
  # perf probe -L 'func;return*:0-10'
  Semantic error :'func;return*' is not a valid function name.
  ...
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150506124647.4961.99473.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:02 -03:00
Masami Hiramatsu
b8dc3984c1 perf probe: Fix a typo for the flags of open
Fix to pass O_APPEND by using bit-or with other flags, instead of
passing it as mode.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hemant@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150506124642.4961.97878.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:01 -03:00
Masami Hiramatsu
ae2cb1ac60 perf probe: Fix to close probe_events file in error
Fix perf-probe to close probe_events file if it failed to get existing
probe's name. This also fix the return error code to -ENOMEM.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: hemant@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/20150506124640.4961.26062.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:05:01 -03:00
Masami Hiramatsu
307a464b23 perf probe: Allow to use filter on --del command
This makes perf-probe --del option to accept filter rules
not only simple glob pattern. This simplifies the code and
improve the flexibility.

E.g. if we remove 2 different pattern events, we need 2
     -d options.
  ----
  # ./perf probe -d vfs\* -d malloc
  Removed event: probe_libc:malloc
  Removed event: probe:vfs_read
  ----

  This allows you to joint the 2 patterns with '|'.

  ----
  # ./perf probe -d 'vfs*|malloc'
  Removed event: probe:vfs_read
  Removed event: probe_libc:malloc
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150505022948.23399.4197.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-05 18:13:02 -03:00
Wang Nan
e59d29e88f perf probe: Fix segfault if passed with ''.
Since parse_perf_probe_point() deals with a user passed argument, we
should not assume it to be a valid string.

Without this patch, if pass '' to perf probe, a segfault raises:

 $ perf probe -a ''
 Segmentation fault

This patch checks argument of parse_perf_probe_point() before
string processing.

After this patch:

 $ perf probe -a ''

  usage: perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]
     or: perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]
     ...

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1430210769-94177-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-05 12:26:52 -03:00
Masami Hiramatsu
b6a896438b perf probe: Accept filter argument for --list
Currently, perf-probe --list option ignores given event filter.
  ----
  # ./perf probe -l vfs\*
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
    probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
  ----

This changes --list option to accept the event filter argument as below.
  ----
  # ./perf probe -l vfs\*
    probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
  # ./perf probe -l \*libc:\*
    probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17.so)
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150424094750.23967.53868.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:56 -03:00
Naveen N. Rao
3099c02600 perf probe: Improve detection of file/function name in the probe pattern
Currently, perf probe considers patterns including a '.' to be a file.
However, this causes problems on powerpc ABIv1 where all functions have
a leading '.':

  $ perf probe -F | grep schedule_timeout_interruptible
  .schedule_timeout_interruptible
  $ perf probe .schedule_timeout_interruptible
  Semantic error :File always requires line number or lazy pattern.
    Error: Command Parse Error.

Fix this:
- by checking the probe pattern in more detail, and
- skipping leading dot if one exists when creating/deleting events.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/db680f7cb11c4452b632f908e67151f3aa0f4602.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:53 -03:00
Naveen N. Rao
7b6ff0bdbf perf probe ppc64le: Fixup function entry if using kallsyms lookup
On powerpc ABIv2, if no debug-info is found and we use kallsyms, we need
to fixup the function entry to point to the local entry point. Use
offset of 8 since current toolchains always generate 2 instructions (8
bytes).

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/92253021e77a104b23b615c8c23bf9501dfe60bf.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:47 -03:00
Naveen N. Rao
d5c2e2c17a perf probe ppc64le: Prefer symbol table lookup over DWARF
Use symbol table lookups by default if DWARF is not necessary, since
powerpc ABIv2 encodes local entry points in the symbol table and the
function entry address in DWARF may not be appropriate for kprobes, as
described here:

https://sourceware.org/bugzilla/show_bug.cgi?id=17638

"The DWARF address ranges deliberately include the *whole* function,
both global and local entry points."
...
"If you want to set probes on a local entry point, you should look up
the symbol in the main symbol table (not DWARF), and check the st_other
bits; they will indicate whether the function has a local entry point,
and what its offset from the global entry point is.  Note that GDB does
the same when setting a breakpoint on a function entry."

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/88a10e22f4aaba2aef812824ca4b10d7beeea012.1430217967.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-04 12:43:46 -03:00
Masami Hiramatsu
6dbe31f7ba perf probe: Remove all probes matches given pattern at once
Fix perf-probe --del option to delete all matched probes in both
of kprobes and uprobes at once.

When we have 2 or more events on different binaries as below,

  ----
  # ./perf probe -l
  probe:vfs_read       (on vfs_read@ksrc/linux-3/fs/read_write.c)
  probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.17
  ----

Trying to remove all event with '*' just removes kprobe events at first.
  ----
  # ./perf probe -d \*
  Removed event: probe:vfs_read
  ----

And in 2nd try, it removes all uprobe events.
  ----
  # ./perf probe -d \*
  Removed event: probe_libc:malloc
  ----

This fixes to remove all event at once as below.
  ----
  # ./perf probe -d \*
  Removed event: probe:vfs_read
  Removed event: probe_libc:malloc
  ----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150423134614.26128.18106.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-29 10:38:03 -03:00
Naohiro Aota
09ed8975c4 perf probe: Find compilation directory path for lazy matching
If we use lazy matching, it failed to open a souce file if perf command
is invoked outside of compilation directory:

$ perf probe -a '__schedule;clear_*'
Failed to open kernel/sched/core.c: No such file or directory
  Error: Failed to add events. (-2)

OTOH, other commands like "probe -L" can solve the souce directory by
themselves. Let's make it possible for lazy matching too!

Signed-off-by: Naohiro Aota <naota@elisp.net>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1426223923-1493-1-git-send-email-naota@elisp.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-13 20:11:05 -03:00
He Kuang
9d7b45c572 perf probe: Set retprobe flag when probe in address-based alternative mode
When perf probe searched in a debuginfo file and failed, it tried with
an alternative, in function get_alternative_probe_event():

        memcpy(tmp, &pev->point, sizeof(*tmp));
        memset(&pev->point, 0, sizeof(pev->point));

In this case, it drops the retprobe flag and forgets to set it back in
find_alternative_probe_point(), so the problem occurs.

Can be reproduced as following:

  $ perf probe -v -k vmlinux --add='sys_write%return'
  ...
  Added new event:
  Writing event: p:probe/sys_write _stext+1584952
    probe:sys_write      (on sys_write%return)

  $ cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/sys_write _stext+1584952

After this patch:

  $ perf probe -v -k vmlinux --add='sys_write%return'
  Added new event:
  Writing event: r:probe/sys_write SyS_write+0
    probe:sys_write      (on sys_write%return)

  $ cat /sys/kernel/debug/tracing/kprobe_events
  r:probe/sys_write SyS_write

Signed-off-by: He Kuang <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1428925290-5623-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-13 17:25:22 -03:00
Masami Hiramatsu
7afb3fab39 perf probe: Support multiple probes on different binaries
Support multiple probes on different binaries with just
one command.

In the result, this example sets up the probes on icmp_rcv in
kernel, on main and set_target in perf, and on pcspkr_event
in pcspker.ko driver.
  -----
  # perf probe -a icmp_rcv -x ./perf -a main -a set_target \
   -m /lib/modules/4.0.0-rc5+/kernel/drivers/input/misc/pcspkr.ko \
   -a pcspkr_event
  Added new event:
    probe:icmp_rcv       (on icmp_rcv)

  You can now use it in all perf tools, such as:

          perf record -e probe:icmp_rcv -aR sleep 1

  Added new event:
    probe_perf:main      (on main in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:main -aR sleep 1

  Added new event:
    probe_perf:set_target (on set_target in /home/mhiramat/ksrc/linux-3/tools/perf/perf)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:set_target -aR sleep 1

  Added new event:
    probe:pcspkr_event   (on pcspkr_event in pcspkr)

  You can now use it in all perf tools, such as:

          perf record -e probe:pcspkr_event -aR sleep 1
  -----

Reported-by: Arnaldo Carvalho de Melo <acme@infradead.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150401102539.17137.46454.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-10 10:19:53 -03:00
Wang Nan
f6c15621f0 perf probe: Fix ARM 32 building error
Commit 9b118acae3 ("perf probe: Fix to
handle aliased symbols in glibc") uses an absolute format '%lx' to
print u64 argument, which causes compiling error on ARM 32.

This patch replaces it with PRIx64.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1428459274-138470-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08 10:49:48 -03:00
Wang Nan
ba92732e98 perf kmaps: Check kmaps to make code more robust
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.

Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).

Also, introduces map__kmaps() to warn uninitialized kmaps.

Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-04-08 09:07:03 -03:00
Masami Hiramatsu
e6d7c91c8c perf probe: Fix to get ummapped symbol address on kernel
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 <masami.hiramatsu.pt@hitachi.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150322114022.32639.19096.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-24 12:07:04 -03:00
He Kuang
0560a0c4a1 perf probe: Fix failure to add multiple probes without debuginfo
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 using kernel_get_ref_reloc_sym() to get ref_reloc_sym.

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 <hekuang@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1426816616-2394-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-21 14:53:21 -03:00
David Ahern
6d4a48968b perf probe: Fix compiles due to declarations using perf_probe_point
perf fails to build with gcc "(GCC) 4.4.7 20120313 (Red Hat
4.4.7-4.0.9)" (a.k.a., RHEL6 / CentOS 6 / OL 6):

  cc1: warnings being treated as errors
  util/probe-event.c: In function ‘get_alternative_line_range’:
  util/probe-event.c:359: error: missing initializer
  util/probe-event.c:359: error: (near initialization for ‘pp.file’)
  util/probe-event.c:359: error: missing initializer
  util/probe-event.c:359: error: (near initialization for ‘result.function’)

Fix by bringing in initializers to declaration.

Signed-off-by: David Ahern <david.ahern@oracle.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1426084580-60780-1-git-send-email-david.ahern@oracle.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:40:00 -03:00
He Kuang
a78604deff perf probe: Fix possible double free on error
A double free occurred when get source file path failed. If lr->path
failed to assign a new value, it will be freed as the old path and then
be freed again during line_range__clear(), and causes this:

  $ perf probe -L do_execve -k vmlinux
  *** Error in `/usr/bin/perf': double free or corruption (fasttop):
      0x0000000000a9ac50 ***
  ======= Backtrace: =========
  ../lib64/libc.so.6(+0x6eeef)[0x7ffff5e44eef]
  ../lib64/libc.so.6(+0x78cae)[0x7ffff5e4ecae]
  ../lib64/libc.so.6(+0x79987)[0x7ffff5e4f987]
  ../bin/perf[0x4ab41f]
  ...

This patch fix this problem.

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425463302-1687-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:58 -03:00
Namhyung Kim
e578da3b20 perf probe: Allow weak symbols to be probed
It currently prevents adding probes in weak symbols.  But there're cases
that given name is an only weak symbol so that we cannot add probe.

  $ perf probe -x /usr/lib/libc.so.6 -a calloc
  Failed to find symbol calloc in /usr/lib/libc-2.21.so
    Error: Failed to add events.

  $ nm /usr/lib/libc.so.6 | grep calloc
  000000000007b1f0 t __calloc
  000000000007b1f0 T __libc_calloc
  000000000007b1f0 W calloc

This change will result in duplicate probes when strong and weak symbols
co-exist in a binary.  But I think it's not a big problem since probes
at the weak symbol will never be hit anyway.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073129.6904.41078.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:55 -03:00
Namhyung Kim
680d926a8c perf symbols: Allow symbol alias when loading map for symbol name
When perf probe tries to add a probe in a binary using symbol name, it
sometimes failed since some symbols were discard during loading dso.

When it resolves an address to symbol, it'd be better to have just one
symbol at given address.  But for finding address from symbol, it'd be
better to keep all names (including aliases).

So allow tools to state that they want to allow aliases via
symbol_conf.allow_aliases.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073127.6904.3232.stgit@localhost.localdomain
[ Original patch passwd allow_alias to many functions, use symbol_conf.allow_aliases instead ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:54 -03:00
Masami Hiramatsu
0687eba787 Revert "perf probe: Fix to fall back to find probe point in symbols"
This reverts commit 906451b98b ("perf probe: Fix to fall back to find probe point in symbols").

Since 'perf probe' now retries with the address of given symbol searched from
map before this path, this fall back routine isn't needed anymore.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073124.6904.1751.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:53 -03:00
Masami Hiramatsu
811dd2ae7c perf probe: Fix --line to handle aliased symbols in glibc
Fix perf probe --line to handle aliased symbols correctly in glibc.

This makes line_range search failing back to address-based alternative
search as same as --add and --vars.

Without this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
  Specified source line is not found.
    Error: Failed to show lines.
  -----

With this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -L malloc
  <__libc_malloc@/usr/src/debug/glibc-2.17-c758a686/malloc/malloc.c:0>
        0  __libc_malloc(size_t bytes)
        1  {
             mstate ar_ptr;
             void *victim;

             __malloc_ptr_t (*hook) (size_t, const __malloc_ptr_t)
        6      = force_reg (__malloc_hook);
        7    if (__builtin_expect (hook != NULL, 0))
        8      return (*hook)(bytes, RETURN_ADDRESS (0));

       10    arena_lookup(ar_ptr);

       12    arena_lock(ar_ptr, bytes);
  -----

Note that this actually shows __libc_malloc, since it is the real
instance of malloc. User can use both __libc_malloc and malloc for
--line.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073122.6904.18540.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:53 -03:00
Masami Hiramatsu
9b118acae3 perf probe: Fix to handle aliased symbols in glibc
Fix perf probe to handle aliased symbols correctly in glibc.  In the
glibc, several symbols are defined as an alias of __libc_XXX, e.g.
malloc is an alias of __libc_malloc.

In such cases, dwarf has no subroutine instances of the alias functions
(e.g. no "malloc" instance), but the map has that symbol and its
address.

Thus, if we search the alieased symbol in debuginfo, we always fail to
find it, but it is in the map.

To solve this problem, this fails back to address-based alternative
search, which searches the symbol in the map, translates its address to
alternative (correct) function name by using debuginfo, and retry to
find the alternative function point from debuginfo.

This adds fail-back process to --vars, --lines and --add options. So,
now you can use those on malloc@libc :)

Without this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
  Failed to find the address of malloc
    Error: Failed to show vars.
  # ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
  Probe point 'malloc' not found in debuginfo.
    Error: Failed to add events.
  -----

With this patch;
  -----
  # ./perf probe -x /usr/lib64/libc-2.17.so -V malloc
  Available variables at malloc
          @<__libc_malloc+0>
                  size_t  bytes
  # ./perf probe -x /usr/lib64/libc-2.17.so -a "malloc bytes"
  Added new event:
    probe_libc:malloc    (on malloc in /usr/lib64/libc-2.17.so with bytes)

  You can now use it in all perf tools, such as:

          perf record -e probe_libc:malloc -aR sleep 1
  -----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150306073120.6904.13779.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-12 12:39:52 -03:00
Masami Hiramatsu
79702f6141 perf probe: Warn if given uprobe event accesses memory on older kernel
Warn if given uprobe event accesses memory on older kernel.

Until 3.14, uprobe event only supports accessing registers so this warns
to upgrade kernel if uprobe-event returns -EINVAL and an argument of the
event accesses memory ($stack, @+offset, and +|-offs() symtax).

With this patch (on 3.10.0-123.13.2.el7.x86_64);
  -----
  # ./perf probe -x ./perf warn_uprobe_event_compat stack=-0\(%sp\)
  Added new event:
  Failed to write event: Invalid argument
  Please upgrade your kernel to at least 3.14 to have access to feature -0(%sp)
    Error: Failed to add events.
  -----

Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20150228025329.32106.70581.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-03-02 12:27:43 -03:00
He Kuang
f56847c2e9 perf probe: Fix a precedence bug
The minus operator has higher precedence than ?: Add parentheses around
?: fix this.

Before this patch:

  $ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
  $ perf probe -l -k ../vmlinux
    kprobes:myprobe      (on do_sys_open)

After this patch:

  $ echo 'p:myprobe do_sys_open' > /sys/kernel/debug/tracing/kprobe_events
  $ perf probe -l -k ../vmlinux
    kprobes:myprobe      (on do_sys_open@linux.git/fs/open.c)

Signed-off-by: He Kuang <hekuang@huawei.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1425034373-14511-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-27 10:31:09 -03:00
Arnaldo Carvalho de Melo
38ae502b1d perf probe: Handle strdup() failure
We could end up returning 0 (Ok) with a NULL raw_path. Fix it.

Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Link: http://lkml.kernel.org/n/tip-l0kcbcg5f4nnzqt01cv42vec@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-27 10:08:29 -03:00
Masami Hiramatsu
eb47cb2eb2 perf probe: Fix get_real_path to free allocated memory in error path
Fix get_real_path to free allocated memory when comp_dir is used for
complementing path and getting an error.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150226082504.28125.74506.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-26 11:59:05 -03:00
Masami Hiramatsu
9aaf5a5f47 perf probe: Check kprobes blacklist when adding new events
Recent linux kernel provides a blacklist of the functions which can not
be probed. perf probe can now check this blacklist before setting new
events and indicate better error message for users.

Without this patch,
  ----
  # perf probe --add vmalloc_fault
  Added new event:
  Failed to write event: Invalid argument
    Error: Failed to add events.
  ----
With this patch
  ----
  # perf probe --add vmalloc_fault
  Added new event:
  Warning: Skipped probing on blacklisted function: vmalloc_fault
  ----

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150219143113.14434.5387.stgit@localhost.localdomain
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-26 11:59:05 -03:00
Steven Rostedt (Red Hat)
23773ca18b perf tools: Make perf aware of tracefs
As tracefs may be mounted instead of debugfs to get to the event
directories, have perf know about tracefs, and use that file system over
debugfs if it is present.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20150202193553.340946602@goodmis.org
[ Fixed up error messages about tracefs pointed out by Namhyung ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-02-11 12:37:08 -03:00
Namhyung Kim
25dd9171f5 perf probe: Fix probing kretprobes
The commit dfef99cd0b ("perf probe: Use ref_reloc_sym based address
instead of the symbol name") converts kprobes to use ref_reloc_sym (i.e.
_stext) and offset instead of using symbol's name directly.  So on my
system, adding do_fork ends up with like below:

  $ sudo perf probe -v --add do_fork%return
  probe-definition(0): do_fork%return
  symbol:do_fork file:(null) line:0 offset:0 return:1 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (7 entries long)
  Using /lib/modules/3.17.6-1-ARCH/build/vmlinux for symbols
  Could not open debuginfo. Try to use symbols.
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: r:probe/do_fork _stext+456136
  Failed to write event: Invalid argument
  Error: Failed to add events. Reason: Operation not permitted (Code: -1)

As you can see, the do_fork was translated to _stext+456136.  This was
because to support (local) symbols that have same name.  But the problem
is that kretprobe requires to be inserted at function start point so it
simply checks whether it's called with offset 0.  And if not, it'll
return with -EINVAL.  You can see it with dmesg.

  $ dmesg | tail -1
    [125621.764103] Return probe must be used without offset.

So we need to use the symbol name instead of ref_reloc_sym in case of
return probes.

Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1421234288-22758-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-01-21 10:06:24 -03:00
Arnaldo Carvalho de Melo
0a3873a8e2 perf symbols: Introduce 'for' method to iterate over the symbols with a given name
Removing boilerplate from two places, where one would have to find the
first entry, then iterate using symbol__next_by_name + strcmp to see if
the next member had the same name.

Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/n/tip-eh73z8gthv20yowirmx2yk38@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-01-21 10:06:15 -03:00
Namhyung Kim
564c62a4d7 perf probe: Do not rely on map__load() filter to find symbols
The find_probe_trace_events_from_map() searches matching symbol from a
map (so from a backing dso).  For uprobes, it'll create a new map (and
dso) and loads it using a filter.  It's a little bit inefficient in that
it'll read out the symbol table everytime but works well anyway.

For kprobes however, it'll reuse existing kernel map which might be
loaded before.  In this case map__load() just returns with no result.
It makes kprobes always failed to find symbol even if it exists in the
map (dso).

To fix it, use map__find_symbol_by_name() instead.  It'll load a map
with full symbols and sorts them by name.  It needs to search sibing
nodes since there can be multiple (local) symbols with same name.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/1421234288-22758-3-git-send-email-namhyung@kernel.org
[ Use symbol__next_by_name ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-01-21 10:06:02 -03:00
Namhyung Kim
7949ba1fa2 perf probe: Propagate error code when write(2) failed
When it failed to write probe commands to the probe_event file in
debugfs, it needs to propagate the error code properly.  Current code
blindly uses the return value of the write(2) so it always uses
-1 (-EPERM) and it might confuse users.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1420886028-15135-4-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-01-16 17:49:28 -03:00
Masami Hiramatsu
906451b98b perf probe: Fix to fall back to find probe point in symbols
Fix to fall back to find a probe point in symbols if perf fails to find
it in debuginfo.

This can happen when the target function is an alias of another
function. Such alias doesn't have an entry in debuginfo but in symbols.

David Ahern reported this problem in https://lkml.org/lkml/2014/12/29/355

I ensured the problem and deeper investigation discovers it.
 -----
 eu-readelf --debug-dump=info /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep \"malloc\" -A6
             name                 (strp) "malloc"
             decl_file            (data1) 25
             decl_line            (data2) 466
             prototyped           (flag_present)
             type                 (ref4) [  81b5]
             declaration          (flag_present)
 [  8f58]      formal_parameter
 --
             name                 (strp) "malloc"
             decl_file            (data1) 23
             decl_line            (data2) 466
             prototyped           (flag_present)
             type                 (ref4) [  9f4a]
             declaration          (flag_present)
             sibling              (ref4) [  bb29]
 ...
 -----
All these entires have no instances (all of them are declarations)
This is why the perf probe failed to find it in debuginfo.

However, there are some malloc instances in symbols.
 -----
 eu-readelf --symbols /usr/lib/debug/lib/x86_64-linux-gnu/libc-2.19.so | grep malloc$
  1181: 0000000000080700   5332 FUNC    LOCAL  DEFAULT       12 _int_malloc
  4537: 00000000000831d0    339 FUNC    LOCAL  DEFAULT       12 __GI___libc_malloc
  5545: 00000000000831d0    339 FUNC    LOCAL  DEFAULT       12 __malloc
  6063: 00000000000831d0    339 FUNC    GLOBAL DEFAULT       12 malloc
  7302: 00000000000831d0    339 FUNC    GLOBAL DEFAULT       12 __libc_malloc
 -----
As you an see, malloc and __libc_malloc have same address, and actually
__libc_malloc has an entry in debuginfo. So you can set up a probe on
__libc_malloc.

To fix this problem shortly, perf probe simply falls back to find probe
point(malloc) in symbols if it is not found in debuginfo.

Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20141231062747.2087.80961.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-01-02 12:42:17 -03:00
Masami Hiramatsu
5e17b28f1e perf probe: Add --quiet option to suppress output result message
Add --quiet(-q) option to suppress output result message for --add, and
--del options (Note that --lines/funcs/vars are not affected). This
option is useful if you run the perf probe inside your scripts.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20141027203131.21219.35170.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-10-29 10:32:49 -02:00
Waiman Long
8fa7d87f91 perf symbols: Encapsulate dsos list head into struct dsos
This is a precursor patch to enable long name searching of DSOs using
a rbtree.

In this patch, a new dsos structure is created which contains only a
list head structure for the moment.

The new dsos structure is used, in turn, in the machine structure for
the user_dsos and kernel_dsos fields.

Only the following 3 dsos functions are modified to accept the new dsos
structure parameter instead of list_head:

 - dsos__add()
 - dsos__find()
 - __dsos__findnew()

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Douglas Hatch <doug.hatch@hp.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Link: http://lkml.kernel.org/r/1412021249-19201-2-git-send-email-Waiman.Long@hp.com
[ Move struct dsos to dso.h to reduce the dso methods depends on machine.h ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-09-30 12:11:49 -03:00
Masami Hiramatsu
2b394bc446 perf probe: Do not access kallsyms when analyzing user binaries
Do not access kallsyms to show available variables and show source lines
in user binaries.

This behavior always requires the root privilege when sysctl sets
kernel.kptr_restrict=1, but we don't need it just for analyzing user
binaries.

Without this patch (by normal user, kptr_restrict=1):
  ----
  $ perf probe -x ./perf -V add_cmdname
  Failed to init vmlinux path.
    Error: Failed to show vars.
  $ perf probe -x ./perf -L add_cmdname
  Failed to init vmlinux path.
    Error: Failed to show lines.
  ----

With this patch:
  ----
  $ perf probe -x ./perf -V add_cmdname
  Available variables at add_cmdname
          @<perf_unknown_cmd_config+144>
                  (No matched variables)
          @<list_commands_in_dir+160>
                  (No matched variables)
          @<add_cmdname+0>
                  char*   name
                  size_t  len
                  struct cmdnames*        cmds
  $ perf probe -x ./perf -L add_cmdname
  <add_cmdname@/home/fedora/ksrc/linux-3/tools/perf/util/help.c:0>
        0  void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
        1  {
        2         struct cmdname *ent = malloc(sizeof(*ent) + len + 1);

        4         ent->len = len;
        5         memcpy(ent->name, name, len);
        6         ent->name[len] = 0;
  ...
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: david lerner <dlernerdroid@gmail.com>
Cc: linux-perf-user@vger.kernel.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140917084054.3722.73975.stgit@kbuild-f20.novalocal
[ Added missing 'bool user' argument to the !DWARF show_line_range() stub ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-09-17 18:01:14 -03:00
Masami Hiramatsu
5f03cba415 perf probe: Make error messages thread-safe
To make error messages thread-safe, this replaces strerror with
strerror_r for warnings, and just shows the return value instead of
using strerror for debug messages.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022234.3545.22199.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-15 10:56:53 -03:00
Masami Hiramatsu
6eb0866096 perf probe: Don't use strerror if strlist__add failed
Since the strlist__add doesn't involves any IO, the failure reason must
be ENOMEM or EINVAL, moreover this is just a debug message, we don't
need to show the error string.

And also, if get_probe_trace_command_rawlist() returns NULL, it doesn't
mean the rawlist is empty, there is an error.  So caller must use
-ENOMEM for the error.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022230.3545.99254.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-15 10:53:36 -03:00
Masami Hiramatsu
92561cb788 perf probe: Warn user to rebuild target with debuginfo
Warn user to rebuild target with debuginfo when the perf probe fails to
find debug information in the target binary.

Without this, perf probe just reports the failure, but it's no hint for
users. This gives more hint for users.

Without this:

  $ strip perf
  $ ./perf probe -x perf -L argv_split
  Failed to open debuginfo file.
    Error: Failed to show lines.

With this:

  $ strip perf
  $ ./perf probe -x perf -L argv_split
  The /home/fedora/ksrc/linux-3/tools/perf/perf file has no debug information.
  Rebuild with -g, or install an appropriate debuginfo package.
    Error: Failed to show lines.

The "rebuild with ..." part changes to "rebuild with CONFIG_DEBUG_INFO"
if the target is the kernel or a kernel module.

Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140815014432.29869.57941.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-15 10:32:43 -03:00
Namhyung Kim
0a7e6d1b68 perf tools: Check recorded kernel version when finding vmlinux
Currently vmlinux_path__init() only tries to find vmlinux file from
current directory, /boot and some canonical directories with version
number of the running kernel.  This can be a problem when reporting old
data recorded on a kernel version not running currently.

We can use --symfs option for this but it's annoying for user to do it
always.  As we already have the info in the perf.data file, it can be
changed to use it for the search automatically.

Before:

  $ perf report
  ...
  # Samples: 4K of event 'cpu-clock'
  # Event count (approx.): 1067250000
  #
  # Overhead  Command     Shared Object      Symbol
  # ........  ..........  .................  ..............................
      71.87%     swapper  [kernel.kallsyms]  [k] recover_probed_instruction

After:

  # Overhead  Command     Shared Object      Symbol
  # ........  ..........  .................  ....................
      71.87%     swapper  [kernel.kallsyms]  [k] native_safe_halt

This requires to change signature of symbol__init() to receive struct
perf_session_env *.

Reported-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1407825645-24586-14-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-13 16:42:21 -03:00
Masami Hiramatsu
467ec08567 perf probe: Fix --del option to delete events only with uprobe events
Current perf probe --del doesn't work if only CONFIG_UPROBE_EVENTS=y
because it aborts when it fails to open kprobe_events file before
checking uprobe_events file.

This fixes --del option to delete dynamic events if it can open either
kprobe_events or uprobe_events. Only if it failed to open both of them,
it shows an error message and aborts.

Without this patch, if we run perf probe -d on the kernel configured
with CONFIG_KPROBE_EVENTS=n and CONFIG_UPROBE_EVENTS=y,

  # perf probe -d \*
  kprobe_events file does not exist - please rebuild kernel with CONFIG_KPROBE_EVENTS.
    Error: Failed to delete events.

With this patch,

  # perf probe -d \*
  Removed event: probe_perf:alloc_event

Changes in v2:
 - Use strerror_r instead of strerror.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140813161250.26440.24028.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-13 15:54:11 -03:00
Masami Hiramatsu
5e45187cc9 perf probe: Fix --list option to show events only with uprobe events
Current perf probe --list doesn't work if only CONFIG_UPROBE_EVENTS=y
because it aborts when it fails to open kprobe_events file before
checking uprobe_events file.

This fixes --list option to show dynamic events if it can open either
kprobe_events or uprobe_events. Only if it failed to open both of them,
it shows an error message and aborts.

Without this patch, if we run perf probe -l on the kernel configured
with CONFIG_KPROBE_EVENTS=n and CONFIG_UPROBE_EVENTS=y,

  # perf probe -l
  /sys/kernel/debug/tracing/kprobe_events file does not exist - please rebuild ker
    Error: Failed to show event list.

With this patch,

  # perf probe -l
    probe_perf:alloc_event (on alloc_event@lib/traceevent/event-parse.c in /home/fedora/ksrc/linux-3/tools/perf/perf)

Changes in v2:
 - Use strerror_r instead of strerror.

Reported-by: Naohiro Aota <naota@elisp.net>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140813161248.26440.84370.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-08-13 15:53:35 -03:00
Masami Hiramatsu
5ee05b8801 perf probe: Improve error messages in --line option
Improve error messages of 'perf probe --line' mode.

Currently 'perf probe' shows the "Debuginfo analysis failed" message with
an error code when the given symbol is not found:

  -----
  # perf probe -L page_cgroup_init_flatmem
  Debuginfo analysis failed. (-2)
    Error: Failed to show lines.
  -----

But -2 (-ENOENT) means that the given source line or function was not
found. With this patch, 'perf probe' shows the correct error message:

  -----
  # perf probe -L page_cgroup_init_flatmem
  Specified source line is not found.
    Error: Failed to show lines.
  -----

There is also another debug error code is shown in the same function
after get_real_path(). This removes that too.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140606071406.6788.47850.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-06-10 10:02:06 -03:00
Masami Hiramatsu
69e96eaa4f perf probe: Improve an error message of perf probe --vars mode
Fix an error message when failed to find given address in --vars
mode.

Without this fix, perf probe -V doesn't show the final "Error"
message if it fails to find given source line. Moreover, it
tells it fails to find "variables" instead of the source line.
  -----
  # perf probe -V foo@bar
  Failed to find variables at foo@bar (0)
  -----
The result also shows mysterious error code. Actually the error
returns 0 or -ENOENT means that it just fails to find the address
of given source line. (0 means there is no matching address,
and -ENOENT means there is an entry(DIE) but it has no instance,
e.g. an empty inlined function)

This fixes it to show what happened and the final error message
as below.
  -----
  # perf probe -V foo@bar
  Failed to find the address of foo@bar
    Error: Failed to show vars.
  -----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140606071359.6788.84716.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-06-09 14:35:58 -03:00
Masami Hiramatsu
a15ad2f536 perf probe: Support distro-style debuginfo for uprobe
Support distro-style debuginfo supported by dso for setting uprobes.
Note that this tries to find a debuginfo file based on the real path of
the target binary. If the debuginfo is not correctly installed on the
system, this can not find it.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140206053227.29635.54434.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-02-18 09:38:44 -03:00
Masami Hiramatsu
eb948e5083 perf probe: Allow to add events on the local functions
Allow to add events on the local functions without debuginfo.
(With the debuginfo, we can add events even on inlined functions)
Currently, probing on local functions requires debuginfo to
locate actual address. It is also possible without debuginfo since
we have symbol maps.

Without this change;
  ----
  # ./perf probe -a t_show
  Added new event:
    probe:t_show         (on t_show)

  You can now use it in all perf tools, such as:

          perf record -e probe:t_show -aR sleep 1

  # ./perf probe -x perf -a identity__map_ip
  no symbols found in /kbuild/ksrc/linux-3/tools/perf/perf, maybe install a debug package?
  Failed to load map.
    Error: Failed to add events. (-22)
  ----
As the above results, perf probe just put one event
on the first found symbol for kprobe event. Moreover,
for uprobe event, perf probe failed to find local
functions.

With this change;
  ----
  # ./perf probe -a t_show
  Added new events:
    probe:t_show         (on t_show)
    probe:t_show_1       (on t_show)
    probe:t_show_2       (on t_show)
    probe:t_show_3       (on t_show)

  You can now use it in all perf tools, such as:

          perf record -e probe:t_show_3 -aR sleep 1

  # ./perf probe -x perf -a identity__map_ip
  Added new events:
    probe_perf:identity__map_ip (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
    probe_perf:identity__map_ip_1 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
    probe_perf:identity__map_ip_2 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)
    probe_perf:identity__map_ip_3 (on identity__map_ip in /kbuild/ksrc/linux-3/tools/perf/perf)

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:identity__map_ip_3 -aR sleep 1
  ----
Now we succeed to put events on every given local functions
for both kprobes and uprobes. :)

Note that this also introduces some symbol rbtree
iteration macros; symbols__for_each, dso__for_each_symbol,
and map__for_each_symbol. These are for walking through
the symbol list in a map.

Changes from v2:
  - Fix add_exec_to_probe_trace_events() not to convert address
    to tp->symbol any more.
  - Fix to set kernel probes based on ref_reloc_sym.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140206053225.29635.15026.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-02-18 09:38:43 -03:00