Fix perf probe to find correct variable DIE which has location or
external instance by tracking down the lexical blocks.
Current die_find_variable() expects that the all variable DIEs
which has DW_TAG_variable have a location. However, since recent
dwarf information may have declaration variable DIEs at the
entry of function (subprogram), die_find_variable() returns it.
To solve this problem, it must track down the DIE tree to find
a DIE which has an actual location or a reference for external
instance.
e.g. finding a DIE which origin is <0xdc73>;
<1><11496>: Abbrev Number: 95 (DW_TAG_subprogram)
<11497> DW_AT_abstract_origin: <0xdc42>
<1149b> DW_AT_low_pc : 0x1850
[...]
<2><114cc>: Abbrev Number: 119 (DW_TAG_variable) <- this is a declaration
<114cd> DW_AT_abstract_origin: <0xdc73>
<2><114d1>: Abbrev Number: 119 (DW_TAG_variable)
[...]
<3><115a7>: Abbrev Number: 105 (DW_TAG_lexical_block)
<115a8> DW_AT_ranges : 0xaa0
<4><115ac>: Abbrev Number: 96 (DW_TAG_variable) <- this has a location
<115ad> DW_AT_abstract_origin: <0xdc73>
<115b1> DW_AT_location : 0x486c (location list)
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Acked-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20140529121930.30879.87092.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Fix a segfault bug by asking for variable it doesn't find.
Since the convert_variable() didn't handle error code returned
from convert_variable_location(), it just passed an incomplete
variable field and then a segfault was occurred when formatting
the field.
This fixes that bug by handling success code correctly in
convert_variable(). Other callers of convert_variable_location()
are correctly checking the return code.
This bug was introduced by following commit. But another hidden
erroneous error handling has been there previously (-ENOMEM case).
commit 3d918a12a1
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/20140529105232.28251.30447.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Currently 'make help' message has such hint:
use "make prefix=<path> <install target>" to install to a particular
path like make prefix=/usr/local install install-doc
But this is misleading, when I specify "prefix=/usr/local", it has got no
respect at all.
This is because that, "DESTDIR" is considered first. In this case, "DESTDIR"
has an empty value, so "prefix" is honored. However, "prefix" is unconditionally
assigned to $HOME, regardless of what it is set to from command line. So our
"prefix" setting got no respect and the actual destination falls back to $HOME.
This patch fixes this issue and corrects the help message.
Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1401727474-19370-1-git-send-email-nasa4836@gmail.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
If the perf record command is interrupted in record__mmap_read_all
function, the 'done' is set and err has the latest poll return
value, which is most likely positive number (= number of pollfds
ready to read).
This 'positive err' is then propagated to the exit code, resulting
in not finishing the perf.data header properly, causing following
error in report:
# perf record -F 50000 -a
---
make the system real busy, so there's more chance
to interrupt perf in event writing code
---
^C[ perf record: Woken up 16 times to write data ]
[ perf record: Captured and wrote 30.292 MB perf.data (~1323468 samples) ]
# perf report --stdio > /dev/null
WARNING: The perf.data file's data size field is 0 which is unexpected.
Was the 'perf record' command properly terminated?
Fixing this by checking for positive poll return value
and setting err to 0.
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@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/1401732126-19465-1-git-send-email-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
After output/sort fields refactoring, it's expensive
to check the elide bool in its current location inside
the 'struct sort_entry'.
The perf_hpp__should_skip function gets highly noticable in
workloads with high number of output/sort fields, like for:
$ perf report -i perf-test.data -F overhead,sample,period,comm,pid,dso,symbol,cpu --stdio
Performance report:
9.70% perf [.] perf_hpp__should_skip
Moving the elide bool into the 'struct perf_hpp_fmt', which
makes the perf_hpp__should_skip just single struct read.
Got speedup of around 22% for my test perf.data workload.
The change should not harm any other workload types.
Performance counter stats for (10 runs):
before:
358,319,732,626 cycles ( +- 0.55% )
467,129,581,515 instructions # 1.30 insns per cycle ( +- 0.00% )
150.943975206 seconds time elapsed ( +- 0.62% )
now:
278,785,972,990 cycles ( +- 0.12% )
370,146,797,640 instructions # 1.33 insns per cycle ( +- 0.00% )
116.416670507 seconds time elapsed ( +- 0.31% )
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
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/20140601142622.GA9131@krava.brq.redhat.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
On stdio, there's a problem that it shows invalid values for
callchains in cumulated hist entries. It's because it only cares
about the self period. But with --children behavior, we always add
callchain info to the cumulated entries so it should use the value in
that case.
Before:
# Children Self Command Shared Object Symbol
# ........ ........ ....... ................. ................
#
61.22% 0.32% swapper [kernel.kallsyms] [k] cpu_idle
|
--- cpu_idle
|
|--16530.76%-- start_secondary
|
|--2758.70%-- rest_init
| start_kernel
| x86_64_start_reservations
| x86_64_start_kernel
--6837850969203030.00%-- [...]
After:
# Children Self Command Shared Object Symbol
# ........ ........ ....... ................. ................
#
61.22% 0.32% swapper [kernel.kallsyms] [k] cpu_idle
|
--- cpu_idle
|
|--85.70%-- start_secondary
|
--14.30%-- rest_init
start_kernel
x86_64_start_reservations
x86_64_start_kernel
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1401335910-16832-24-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Add top.children config option for setting default value of
callchain accumulation. It affects the output only if one of
-g or --call-graph option is given as well.
A user can write .perfconfig file like below to enable accumulation
by default:
$ cat ~/.perfconfig
[top]
children = true
And it can be disabled through command line:
$ perf top --no-children
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arun Sharma <asharma@fb.com>
Tested-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1401335910-16832-22-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
The new ->add_entry_cb() will be called after an entry was added to
the histogram. It's used for code sharing between perf report and
perf top. Note that ops->add_*_entry() should set iter->he properly
in order to call the ->add_entry_cb.
Also pass @arg to the callback function. It'll be used by perf top
later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arun Sharma <asharma@fb.com>
Tested-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/87k393g999.fsf@sejong.aot.lge.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Add report.children config option for setting default value of
callchain accumulation. It affects the report output only if
perf.data contains callchain info.
A user can write .perfconfig file like below to enable accumulation
by default:
$ cat ~/.perfconfig
[report]
children = true
And it can be disabled through command line:
$ perf report --no-children
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arun Sharma <asharma@fb.com>
Tested-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1401335910-16832-17-git-send-email-namhyung@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>