Adding initialized arg into unwind__prepare_access to get feedback about
the initialization state.
It's not possible to get it from error code, because we return 0 even in
case we don't recognize dso, which is valid.
The 'initialized' value is used in following patch to speedup
unwind__prepare_access calls logic in fork path.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1467634583-29147-4-git-send-email-jolsa@kernel.org
[ Remove ; after static inline function signatures, fixes build break ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf buildid-cache --add <binary> scans given binary and add
the SDT events to probe cache. "sdt_" prefix is appended for
all SDT providers to avoid event-name clash with other pre-defined
events. It is possible to use the cached SDT events as other cached
events, via perf probe --add "sdt_<provider>:<event>=<event>".
e.g.
----
# perf buildid-cache --add /lib/libc-2.17.so
# perf probe --cache --list | head -n 5
/usr/lib/libc-2.17.so (a6fb821bdf53660eb2c29f778757aef294d3d392):
sdt_libc:setjmp=setjmp
sdt_libc:longjmp=longjmp
sdt_libc:longjmp_target=longjmp_target
sdt_libc:memory_heap_new=memory_heap_new
# perf probe -x /usr/lib/libc-2.17.so \
-a sdt_libc:memory_heap_new=memory_heap_new
Added new event:
sdt_libc:memory_heap_new (on memory_heap_new
in /usr/lib/libc-2.17.so)
You can now use it in all perf tools, such as:
perf record -e sdt_libc:memory_heap_new -aR sleep 1
# perf probe -l
sdt_libc:memory_heap_new (on new_heap+183 in /usr/lib/libc-2.17.so)
----
Note that SDT event entries in probe-cache file is somewhat different
from normal cached events. Normal one starts with "#", but SDTs are
starting with "%".
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: Brendan Gregg <brendan.d.gregg@gmail.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/146736025058.27797.13043265488541434502.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch serves the initial support to identify and list SDT events in
binaries. When programs containing SDT markers are compiled, gcc with
the help of assembler directives identifies them and places them in the
section ".note.stapsdt".
To find these markers from the binaries, one needs to traverse through
this section and parse the relevant details like the name, type and
location of the marker. Also, the original location could be skewed due
to the effect of prelinking. If that is the case, the locations need to
be adjusted.
The functions in this patch open a given ELF, find out the SDT section,
parse the relevant details, adjust the location (if necessary) and
populate them in a list.
A typical note entry in ".note.stapsdt" section is as follows :
|--nhdr.n_namesz--|
------------------------------------
| nhdr | "stapsdt" |
----- |----------------------------------|
| | <location> <base_address> |
| | <semaphore> |
nhdr.n_descsize | "provider_name" "note_name" |
| | <args> |
----- |----------------------------------|
| nhdr | "stapsdt" |
|...
The above shows an excerpt from the section ".note.stapsdt". 'nhdr' is
a structure which has the note name size (n_namesz), note description
size (n_desc_sz) and note type (n_type).
So, in order to parse the note note info, we need nhdr to tell us where
to start from. As can be seen from <sys/sdt.h>, the name of the SDT
notes given is "stapsdt". But this is not the identifier of the note.
After that, we go to description of the note to find out its location, the
address of the ".stapsdt.base" section and the semaphore address.
Then, we find the provider name and the SDT marker name and then follow the
arguments.
Signed-off-by: Hemant Kumar <hemant@linux.vnet.ibm.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736022628.27797.1201368329092908163.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
'perf probe --del' removes caches when '--cache' is given. Note that
the delete pattern is not the same as for normal events.
If you cached probes with event name, --del "eventname" works as
expected. However, if you skipped it, the cached probes doesn't have
actual event name. In that case --del "probe-desc" is required (wildcard
is acceptable). For example a cache entry has the probe-desc "vfs_read
$params", you can remove it with --del 'vfs_read*'.
-----
# perf probe --cache --list
/[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
vfs_read $params
/usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
getaddrinfo $params
# perf probe --cache --del vfs_read\*
Removed cached event: probe:vfs_read
# perf probe --cache --list
/[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
/usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
getaddrinfo $params
-----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.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/146736021651.27797.10250879847070772920.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
New features:
- Allow running 'perf test' entries in the same process, not forking to
test each testcase, useful for debugging (Jiri Olsa)
- Show number of samples in the stdio annotate header (Peter Zijlstra)
Documentation changes:
- Add documentation for perf.data on disk format (Andi Kleen)
Build fixes:
- Fix 'perf trace' build on old systems wrt missing SCHED_RESET_ON_FORK and
eventfd.h (Arnaldo Carvalho de Melo)
Infrastructure changes:
- Utility function to fetch arch from evsel/evlist (Ravi Bangoria)
Trivial changes:
- Fix spelling mistake: "missmatch" -> "mismatch" in libbpf (Colin Ian King)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Staring at annotations of large functions is useless if there's only a
few samples in them. Report the number of samples in the header to make
this easier to determine.
Committer note:
The change amounts to:
- Percent | Source code & Disassembly of perf-vdso.so for cycles:u
------------------------------------------------------------------
+ Percent | Source code & Disassembly of perf-vdso.so for cycles:u (3278 samples)
+--------------------------------------------------------------------------------
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20160630082955.GA30921@twins.programming.kicks-ass.net
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Chris Phlipot
Wang Nan
Jiri Olsa
Masami Hiramatsu
Hemant Kumar
Arnaldo Carvalho de Melo
Ingo Molnar
Peter Zijlstra (Intel)
Ravi Bangoria