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  1. 30 4月, 2014 1 次提交
  3. 20 4月, 2014 2 次提交
  5. 14 4月, 2014 3 次提交
  7. 19 3月, 2014 9 次提交
  9. 15 3月, 2014 9 次提交
  11. 14 3月, 2014 1 次提交
    • D
      perf tools: Fix synthesizing mmaps for threads · bfd66cc7
      由 Don Zickus 提交于 
      Currently if a process creates a bunch of threads using pthread_create
and then perf is run in system_wide mode, the mmaps for those threads
are not captured with a synthesized mmap event.

The reason is those threads are not visible when walking the /proc/
directory looking for /proc/<pid>/maps files.  Instead they are
discovered using the /proc/<pid>/tasks file (which the synthesized comm
event uses).

This causes problems when a program is trying to map a data address to a
tid.  Because the tid has no maps, the event is dropped.  Changing the
program to look up using the pid instead of the tid, finds the correct
maps but creates ugly hacks in the program to carry the correct tid
around.

Fix this by moving the walking of the /proc/<pid>/tasks up a level (out
of the comm function) based on Arnaldo's suggestion.

Tweaked things a bit to special case the 'full' bit and 'guest' check.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1393429527-167840-2-git-send-email-dzickus@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      bfd66cc7
  13. 11 3月, 2014 1 次提交
  15. 10 3月, 2014 2 次提交
  17. 28 2月, 2014 1 次提交
    • J
      perf tools: Fix strict alias issue for find_first_bit · b39c2a57
      由 Jiri Olsa 提交于 
      When compiling perf tool code with gcc 4.4.7 I'm getting
following error:

    CC       util/session.o
  cc1: warnings being treated as errors
  util/session.c: In function ‘perf_session_deliver_event’:
  tools/perf/util/include/linux/bitops.h:109: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  tools/perf/util/include/linux/bitops.h:101: error: dereferencing pointer ‘p’ does break strict-aliasing rules
  util/session.c:697: note: initialized from here
  tools/perf/util/include/linux/bitops.h:101: note: initialized from here
  make[1]: *** [util/session.o] Error 1
  make: *** [util/session.o] Error 2

The aliased types here are u64 and unsigned long pointers, which is safe
for the find_first_bit processing.

This error shows up for me only for gcc 4.4 on 32bit x86, even for
-Wstrict-aliasing=3, while newer gcc are quiet and scream here for
-Wstrict-aliasing={2,1}. Looks like newer gcc changed the rules for
strict alias warnings.

The gcc documentation offers workaround for valid aliasing by using
__may_alias__ attribute:

  http://gcc.gnu.org/onlinedocs/gcc-4.4.0/gcc/Type-Attributes.html

Using this workaround for the find_first_bit function.
Signed-off-by: NJiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
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/1393434867-20271-1-git-send-email-jolsa@redhat.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      b39c2a57
  19. 25 2月, 2014 2 次提交
  21. 24 2月, 2014 3 次提交
  23. 18 2月, 2014 6 次提交
    • M
      perf probe: Support distro-style debuginfo for uprobe · a15ad2f5
      由 Masami Hiramatsu 提交于 
      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: NMasami 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.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      a15ad2f5
    • M
      perf probe: Allow to add events on the local functions · eb948e50
      由 Masami Hiramatsu 提交于 
      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: NMasami 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.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      eb948e50
    • M
      perf probe: Show source-level or symbol-level info for uprobes · 5a6f6314
      由 Masami Hiramatsu 提交于 
      Show source-level or symbol-level information for uprobe events.

Without this change;
  # ./perf probe -l
    probe_perf:dso__load_vmlinux (on 0x000000000006d110 in /kbuild/ksrc/linux-3/tools/perf/perf)

With this change;
  # ./perf probe -l
    probe_perf:dso__load_vmlinux (on dso__load_vmlinux@util/symbol.c in /kbuild/ksrc/linux-3/tools/perf/perf)

Changes from v2:
 - Update according to previous patches.

Changes from v1:
 - Rewrite the code based on new series.
Signed-off-by: NMasami 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/20140206053223.29635.51280.stgit@kbuild-fedora.yrl.intra.hitachi.co.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      5a6f6314
    • M
      perf probe: Show appropriate symbol for ref_reloc_sym based kprobes · 8f33f7de
      由 Masami Hiramatsu 提交于 
      Show appropriate symbol for ref_reloc_sym based kprobes instead of
refpoint+offset when perf-probe -l runs without debuginfo.

Without this change:
  # ./perf probe -l
    probe:t_show         (on _stext+889880 with m v)
    probe:t_show_1       (on _stext+928568 with m v t)
    probe:t_show_2       (on _stext+969512 with m v fmt)
    probe:t_show_3       (on _stext+1001416 with m v file)

With this change:
  # ./perf probe -l
    probe:t_show         (on t_show with m v)
    probe:t_show_1       (on t_show with m v t)
    probe:t_show_2       (on t_show with m v fmt)
    probe:t_show_3       (on t_show with m v file)

Changes from v2:
 - Check ref_reloc_sym to find correct unrelocated address.
Signed-off-by: NMasami 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/20140206053220.29635.81819.stgit@kbuild-fedora.yrl.intra.hitachi.co.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      8f33f7de
    • M
      perf probe: Find given address from offline dwarf · f90acac7
      由 Masami Hiramatsu 提交于 
      Find the given address from offline dwarfs instead of online kernel
dwarfs.

On the KASLR enabled kernel, the kernel text section is loaded with
random offset, and the debuginfo__new_online_kernel can't handle it. So
let's move to the offline dwarf loader instead of using the online dwarf
loader.

As a result, since we don't need debuginfo__new_online_kernel any more,
this also removes the functions related to that.

Without this change;

  # ./perf probe -l
    probe:t_show         (on _stext+901288 with m v)
    probe:t_show_1       (on _stext+939624 with m v t)
    probe:t_show_2       (on _stext+980296 with m v fmt)
    probe:t_show_3       (on _stext+1014392 with m v file)

With this change;

  # ./perf probe -l
    probe:t_show         (on t_show@linux-3/kernel/trace/ftrace.c with m v)
    probe:t_show_1       (on t_show@linux-3/kernel/trace/trace.c with m v t)
    probe:t_show_2       (on t_show@kernel/trace/trace_printk.c with m v fmt)
    probe:t_show_3       (on t_show@kernel/trace/trace_events.c with m v file)

Changes from v2:
 - Instead of retrying, directly opens offline dwarf.
 - Remove debuginfo__new_online_kernel and related functions.
 - Refer map->reloc to get the correct address of a symbol.
 - Add a special case for handling ref_reloc_sym based address.
Signed-off-by: NMasami 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/20140206053218.29635.74821.stgit@kbuild-fedora.yrl.intra.hitachi.co.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      f90acac7
    • M
      perf probe: Use ref_reloc_sym based address instead of the symbol name · dfef99cd
      由 Masami Hiramatsu 提交于 
      Since several local symbols can have same name (e.g. t_show), we need to
use the relative address from the symbol referred by kmap->ref_reloc_sym
instead of the target symbol name itself.

Because the kernel address space layout randomize (kASLR) changes the
absolute address of kernel symbols, we can't rely on the absolute
address.

Note that this works only with debuginfo.

E.g. without this change;
  ----
  # ./perf probe -a "t_show \$vars"
  Added new events:
    probe:t_show         (on t_show with $vars)
    probe:t_show_1       (on t_show with $vars)
    probe:t_show_2       (on t_show with $vars)
    probe:t_show_3       (on t_show with $vars)

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

          perf record -e probe:t_show_3 -aR sleep 1
  ----
OK, we have 4 different t_show()s. All functions have
different arguments as below;
  ----
  # cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/t_show t_show m=%di:u64 v=%si:u64
  p:probe/t_show_1 t_show m=%di:u64 v=%si:u64 t=%si:u64
  p:probe/t_show_2 t_show m=%di:u64 v=%si:u64 fmt=%si:u64
  p:probe/t_show_3 t_show m=%di:u64 v=%si:u64 file=%si:u64
  ----
However, all of them have been put on the *same* address.
  ----
  # cat /sys/kernel/debug/kprobes/list
  ffffffff810d9720  k  t_show+0x0    [DISABLED]
  ffffffff810d9720  k  t_show+0x0    [DISABLED]
  ffffffff810d9720  k  t_show+0x0    [DISABLED]
  ffffffff810d9720  k  t_show+0x0    [DISABLED]
  ----

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

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

          perf record -e probe:t_show_3 -aR sleep 1

  # cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/t_show _stext+889880 m=%di:u64 v=%si:u64
  p:probe/t_show_1 _stext+928568 m=%di:u64 v=%si:u64 t=%si:u64
  p:probe/t_show_2 _stext+969512 m=%di:u64 v=%si:u64 fmt=%si:u64
  p:probe/t_show_3 _stext+1001416 m=%di:u64 v=%si:u64 file=%si:u64

  # cat /sys/kernel/debug/kprobes/list
  ffffffffb50d95e0  k  t_show+0x0    [DISABLED]
  ffffffffb50e2d00  k  t_show+0x0    [DISABLED]
  ffffffffb50f4990  k  t_show+0x0    [DISABLED]
  ffffffffb50eccf0  k  t_show+0x0    [DISABLED]
  ----
This time, each event is put in different address
correctly.

Note that currently this doesn't support address-based
probe on modules (thus the probes on modules are symbol
based), since it requires relative address probe syntax
for kprobe-tracer, and it isn't implemented yet.

One more note, this allows us to put events on correct
address, but --list option should be updated to show
correct corresponding source code.

Changes from v2:
  - Refer kmap->ref_reloc_sym instead of "_stext".
  - Refer map->reloc to catch up the kASLR perf fix.

Changes from v1:
  - Use _stext relative address instead of actual
    absolute address recorded in debuginfo.
Signed-off-by: NMasami 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/20140206053216.29635.22584.stgit@kbuild-fedora.yrl.intra.hitachi.co.jpSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      dfef99cd