linux/tools
Masami Hiramatsu fb7345bbf7 perf probe: Support basic dwarf-based operations on uprobe events
Support basic dwarf(debuginfo) based operations for uprobe events.  With
this change, perf probe can analyze debuginfo of user application binary
to set up new uprobe event.

This allows perf-probe --add(with local variables, line numbers) and
--line works with -x option.  (Actually, --vars has already accepted -x
option)

For example, the following command shows the probe-able lines of a given
user space function. Something that so far was only available in the
'perf probe' tool for kernel space functions:

  # ./perf probe -x perf --line map__load
  <map__load@/home/fedora/ksrc/linux-2.6/tools/perf/util/map.c:0>
        0  int map__load(struct map *map, symbol_filter_t filter)
        1  {
        2         const char *name = map->dso->long_name;
                  int nr;

        5         if (dso__loaded(map->dso, map->type))
        6                 return 0;

        8         nr = dso__load(map->dso, map, filter);
        9         if (nr < 0) {
       10                 if (map->dso->has_build_id) {

And this shows the available variables at the given line of the
function.

  # ./perf probe -x perf --vars map__load:8
  Available variables at map__load:8
          @<map__load+96>
                  char*   name
                  struct map*     map
                  symbol_filter_t filter
          @<map__find_symbol+112>
                  char*   name
                  symbol_filter_t filter
          @<map__find_symbol_by_name+136>
                  char*   name
                  symbol_filter_t filter
          @<map_groups__find_symbol_by_name+176>
                  char*   name
                  struct map*     map
                  symbol_filter_t filter

And lastly, we can now define probe(s) with all available
variables on the given line:

  # ./perf probe -x perf --add 'map__load:8 $vars'

  Added new events:
    probe_perf:map__load (on map__load:8 with $vars)
    probe_perf:map__load_1 (on map__load:8 with $vars)
    probe_perf:map__load_2 (on map__load:8 with $vars)
    probe_perf:map__load_3 (on map__load:8 with $vars)

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

          perf record -e probe_perf:map__load_3 -aR sleep 1

  Changes from previous version:
   - Add examples in the patch description.
   - Use .text section start address and dwarf symbol address
     for calculating the offset of given symbol, instead of
     searching the symbol in symtab again.
     With this change, we can safely handle multiple local
     function instances (e.g. scnprintf in perf).

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@kernel.org>
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: systemtap@sourceware.org
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20131226054152.22364.47021.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-12-26 11:22:01 -03:00
..
cgroup cgroups: fix cgroup_event_listener error handling 2013-01-08 10:00:44 -08:00
firewire
hv Tools: hv: use single send+recv buffer 2013-09-26 12:03:31 -07:00
include/tools tools/include: use stdint types for user-space byteshift headers 2013-07-03 16:02:28 +02:00
lguest tools/lguest: offer VIRTIO_F_ANY_LAYOUT for net device. 2013-07-15 11:18:32 +09:30
lib tools lib traceevent: Use global 'O' processing code 2013-12-19 16:18:12 -03:00
net filter: add minimal BPF JIT image disassembler 2013-03-21 11:35:41 -04:00
nfsd
perf perf probe: Support basic dwarf-based operations on uprobe events 2013-12-26 11:22:01 -03:00
power tools: cpupower: fix wrong err msg not supported vs not available 2013-11-25 23:10:50 +01:00
scripts tools lib traceevent: Add global QUIET_CC_FPIC build output 2013-12-19 16:18:10 -03:00
testing H8/300 has been dead for several years, the kernel for it has 2013-11-12 14:13:14 +09:00
thermal/tmon tools/thermal: Introduce tmon, a tool for thermal subsystem 2013-11-07 08:45:34 +08:00
usb usb: tools: fix a regression issue that gcc can't link to pthread 2013-12-04 15:10:54 -08:00
virtio virtio_test: verify if virtqueue_kick() succeeded 2013-10-29 11:28:16 +10:30
vm tools/: Convert to new topic libraries 2013-12-16 16:03:27 -03:00
Makefile tools/: Convert to new topic libraries 2013-12-16 16:03:27 -03:00