1
linux/tools
Jiri Olsa 7dbf4dcfe2 perf tools: Back [vdso] DSO with real data
Storing data for VDSO shared object, because we need it for the post
unwind processing.

The VDSO shared object is same for all process on a running system, so
it makes no difference when we store it inside the tracer - perf.

When [vdso] map memory is hit, we retrieve [vdso] DSO image and store it
into temporary file.

During the build-id processing phase, the [vdso] DSO image is stored in
build-id db, and build-id reference is made inside perf.data. The
build-id vdso file object is called '[vdso]'. We don't use temporary
file name which gets removed when record is finished.

During report phase the vdso build-id object is treated as any other
build-id DSO object.

Adding following API for vdso object:

  bool is_vdso_map(const char *filename)
    - returns true if the filename matches vdso map name

  struct dso *vdso__dso_findnew(struct list_head *head)
    - find/create proper vdso DSO object

  vdso__exit(void)
    - removes temporary VDSO image if there's any

This change makes backtrace dwarf post unwind possible from [vdso] maps.

Following output is current report of [vdso] sample dwarf backtrace:

  # Overhead  Command      Shared Object                         Symbol
  # ........  .......  .................  .............................
  #
      99.52%       ex  [vdso]             [.] 0x00007fff3ace89af
                   |
                   --- 0x7fff3ace89af

Following output is new report of [vdso] sample dwarf backtrace:

  # Overhead  Command      Shared Object                         Symbol
  # ........  .......  .................  .............................
  #
      99.52%       ex  [vdso]             [.] 0x00000000000009af
                   |
                   --- 0x7fff3ace89af
                       main
                       __libc_start_main
                       _start

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347295819-23177-5-git-send-email-jolsa@redhat.com
[ committer note: s/ALIGN/PERF_ALIGN/g to cope with the android build changes ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-09-11 12:08:30 -03:00
..
firewire
hv Tools: hv: verify origin of netlink connector message 2012-06-10 00:29:46 +09:00
include/tools
lguest
lib/traceevent tools lib traceevent: replace mempcpy with memcpy 2012-09-07 22:11:20 -03:00
nfsd
perf perf tools: Back [vdso] DSO with real data 2012-09-11 12:08:30 -03:00
power tools/power: turbostat: fix large c1% issue 2012-07-19 22:26:33 -04:00
scripts perf tools: Let O= makes handle relative paths 2012-08-16 14:11:11 -03:00
testing fault-injection: fix failcmd.sh warning 2012-07-31 18:42:38 -07:00
usb testusb: expose looping forever option "l" to user 2012-06-13 16:15:03 -07:00
virtio virtio/tools: add delayed interupt mode 2012-05-02 18:22:14 +03:00
vm mm: Fix signal SIGFPE in slabinfo.c. 2012-07-02 23:11:14 +03:00
Makefile