Symbolize stack traces by creating a live machine. Add this
functionality to dump_stack and switch dump_stack users to use
it. Switch TUI to use it. Add stack traces to the child test function
which can be useful to diagnose blocked code.
Example output:
```
$ perf test -vv PERF_RECORD_
...
7: PERF_RECORD_* events & perf_sample fields:
7: PERF_RECORD_* events & perf_sample fields : Running (1 active)
^C
Signal (2) while running tests.
Terminating tests with the same signal
Internal test harness failure. Completing any started tests:
: 7: PERF_RECORD_* events & perf_sample fields:
---- unexpected signal (2) ----
#0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#2 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
#3 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
#4 0x7fc12fef1393 in __nanosleep nanosleep.c:26
#5 0x7fc12ff02d68 in __sleep sleep.c:55
#6 0x55788c63196b in test__PERF_RECORD perf-record.c:0
#7 0x55788c620fb0 in run_test_child builtin-test.c:0
#8 0x55788c5bd18d in start_command run-command.c:127
#9 0x55788c621ef3 in __cmd_test builtin-test.c:0
#10 0x55788c6225bf in cmd_test ??:0
#11 0x55788c5afbd0 in run_builtin perf.c:0
#12 0x55788c5afeeb in handle_internal_command perf.c:0
#13 0x55788c52b383 in main ??:0
#14 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
#15 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
#16 0x55788c52b9d1 in _start ??:0
---- unexpected signal (2) ----
#0 0x55788c6210a3 in child_test_sig_handler builtin-test.c:0
#1 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#2 0x7fc12fea3a14 in pthread_sigmask@GLIBC_2.2.5 pthread_sigmask.c:45
#3 0x7fc12fe49fd9 in __GI___sigprocmask sigprocmask.c:26
#4 0x7fc12ff2601b in __longjmp_chk longjmp.c:36
#5 0x55788c6210c0 in print_test_result.isra.0 builtin-test.c:0
#6 0x7fc12fe49df0 in __restore_rt libc_sigaction.c:0
#7 0x7fc12fe99687 in __internal_syscall_cancel cancellation.c:64
#8 0x7fc12fee5f7a in clock_nanosleep@GLIBC_2.2.5 clock_nanosleep.c:72
#9 0x7fc12fef1393 in __nanosleep nanosleep.c:26
#10 0x7fc12ff02d68 in __sleep sleep.c:55
#11 0x55788c63196b in test__PERF_RECORD perf-record.c:0
#12 0x55788c620fb0 in run_test_child builtin-test.c:0
#13 0x55788c5bd18d in start_command run-command.c:127
#14 0x55788c621ef3 in __cmd_test builtin-test.c:0
#15 0x55788c6225bf in cmd_test ??:0
#16 0x55788c5afbd0 in run_builtin perf.c:0
#17 0x55788c5afeeb in handle_internal_command perf.c:0
#18 0x55788c52b383 in main ??:0
#19 0x7fc12fe33ca8 in __libc_start_call_main libc_start_call_main.h:74
#20 0x7fc12fe33d65 in __libc_start_main@@GLIBC_2.34 libc-start.c:128
#21 0x55788c52b9d1 in _start ??:0
7: PERF_RECORD_* events & perf_sample fields : Skip (permissions)
```
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250624210500.2121303-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Add a new debug option "type-profile" to enable the detailed info during
the type analysis especially for instruction tracking. You can use this
before the command name like 'report' or 'annotate'.
$ perf --debug type-profile annotate --data-type
Committer testing:
First get some memory events:
$ perf mem record ls
Then, without data-type profiling debug:
$ perf annotate --data-type | head
Annotate type: 'struct rtld_global' in /usr/lib64/ld-linux-x86-64.so.2 (1 samples):
============================================================================
samples offset size field
1 0 4336 struct rtld_global {
0 0 0 struct link_namespaces* _dl_ns;
0 2560 8 size_t _dl_nns;
0 2568 40 __rtld_lock_recursive_t _dl_load_lock {
0 2568 40 pthread_mutex_t mutex {
0 2568 40 struct __pthread_mutex_s __data {
0 2568 4 int __lock;
$
And with only data-type profiling:
$ perf --debug type-profile annotate --data-type | head
-----------------------------------------------------------
find_data_type_die [1e67] for reg13873052 (PC) offset=0x150e2 in dl_main
CU die offset: 0x29cd3
found PC-rel by addr=0x34020 offset=0x20
-----------------------------------------------------------
find_data_type_die [2e] for reg12 offset=0 in __GI___readdir64
CU die offset: 0x137a45
frame base: cfa=1 fbreg=-1
found "__futex" in scope=2/2 (die: 0x137ad5) 0(reg12) type=int (die:2a)
-----------------------------------------------------------
find_data_type_die [52] for reg5 offset=0 in __memmove_avx_unaligned_erms
CU die offset: 0x1124ed
no variable found
Annotate type: 'struct rtld_global' in /usr/lib64/ld-linux-x86-64.so.2 (1 samples):
============================================================================
samples offset size field
1 0 4336 struct rtld_global {
0 0 0 struct link_namespaces* _dl_ns;
0 2560 8 size_t _dl_nns;
0 2568 40 __rtld_lock_recursive_t _dl_load_lock {
0 2568 40 pthread_mutex_t mutex {
0 2568 40 struct __pthread_mutex_s __data {
0 2568 4 int __lock;
$
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20240319055115.4063940-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This reverts commit 08efcb4a63.
This breaks the build as it will prefer using libbpf-devel header files,
even when not using LIBBPF_DYNAMIC=1, breaking the build.
This was detected on OpenSuSE Tumbleweed with libtraceevent-devel 1.3.0,
as described by Jiri Slaby:
=======================================================================
It breaks build with LIBTRACEEVENT_DYNAMIC and version 1.3.0:
> util/debug.c: In function ‘perf_debug_option’:
> util/debug.c:243:17: error: implicit declaration of function
‘tep_set_loglevel’ [-Werror=implicit-function-declaration]
> 243 | tep_set_loglevel(TEP_LOG_INFO);
> | ^~~~~~~~~~~~~~~~
> util/debug.c:243:34: error: ‘TEP_LOG_INFO’ undeclared (first use in this
function); did you mean ‘TEP_PRINT_INFO’?
> 243 | tep_set_loglevel(TEP_LOG_INFO);
> | ^~~~~~~~~~~~
> | TEP_PRINT_INFO
> util/debug.c:243:34: note: each undeclared identifier is reported only once
for each function it appears in
> util/debug.c:245:34: error: ‘TEP_LOG_DEBUG’ undeclared (first use in this
function)
> 245 | tep_set_loglevel(TEP_LOG_DEBUG);
> | ^~~~~~~~~~~~~
> util/debug.c:247:34: error: ‘TEP_LOG_ALL’ undeclared (first use in this
function)
> 247 | tep_set_loglevel(TEP_LOG_ALL);
> | ^~~~~~~~~~~
It is because the gcc's command line looks like:
gcc
...
-I/home/abuild/rpmbuild/BUILD/tools/lib/
...
-DLIBTRACEEVENT_VERSION=65790
...
=======================================================================
The proper way to fix this is more involved and so not suitable for this
late in the 5.16-rc stage.
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/lkml/bc2b0786-8965-1bcd-2316-9d9bb37b9c31@kernel.org
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/lkml/YddGjjmlMZzxUZbN@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow to display time in perf debug output via new
debug_set_display_time function.
It will be used in perf daemon command to get verbose output into log
file.
The debug time format is:
[2020-12-03 18:25:31.822152] affinity: SYS
[2020-12-03 18:25:31.822164] mmap flush: 1
[2020-12-03 18:25:31.822175] comp level: 0
[2020-12-03 18:25:32.002047] mmap size 528384B
Committer notes:
Cast tod.tv_usec to long to avoid this problem:
78 12.70 ubuntu:18.04-x-sparc64 : FAIL sparc64-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
util/debug.c: In function 'fprintf_time':
util/debug.c:63:32: error: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type '__suseconds_t {aka int}' [-Werror=format=]
return fprintf(file, "[%s.%06lu] ", date, tod.tv_usec);
~~~~^ ~~~~~~~~~~~
%06u
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20210102220441.794923-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Perf record with verbose=2 already prints this information along with
whole lot of other traces which requires lot of scrolling. Introduce
an option to print only perf_event_open() arguments and return value.
Sample o/p:
$ perf --debug perf-event-open=1 record -- ls > /dev/null
------------------------------------------------------------
perf_event_attr:
size 112
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|PERIOD
read_format ID
disabled 1
inherit 1
exclude_kernel 1
mmap 1
comm 1
freq 1
enable_on_exec 1
task 1
precise_ip 3
sample_id_all 1
exclude_guest 1
mmap2 1
comm_exec 1
ksymbol 1
bpf_event 1
------------------------------------------------------------
sys_perf_event_open: pid 4308 cpu 0 group_fd -1 flags 0x8 = 4
sys_perf_event_open: pid 4308 cpu 1 group_fd -1 flags 0x8 = 5
sys_perf_event_open: pid 4308 cpu 2 group_fd -1 flags 0x8 = 6
sys_perf_event_open: pid 4308 cpu 3 group_fd -1 flags 0x8 = 8
sys_perf_event_open: pid 4308 cpu 4 group_fd -1 flags 0x8 = 9
sys_perf_event_open: pid 4308 cpu 5 group_fd -1 flags 0x8 = 10
sys_perf_event_open: pid 4308 cpu 6 group_fd -1 flags 0x8 = 11
sys_perf_event_open: pid 4308 cpu 7 group_fd -1 flags 0x8 = 12
------------------------------------------------------------
perf_event_attr:
type 1
size 112
config 0x9
watermark 1
sample_id_all 1
bpf_event 1
{ wakeup_events, wakeup_watermark } 1
------------------------------------------------------------
sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8
sys_perf_event_open failed, error -13
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.002 MB perf.data (9 samples) ]
Committer notes:
Just like the 'verbose' variable this new 'debug_peo_args' needs to be
added to util/python.c, since we don't link the debug.o file in the
python binding, which ended up making 'perf test python' fail with:
# perf test -v python
18: 'import perf' in python :
--- start ---
test child forked, pid 19237
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: /tmp/build/perf/python/perf.so: undefined symbol: debug_peo_args
test child finished with -1
---- end ----
'import perf' in python: FAILED!
#
After adding that new variable to util/python.c:
# perf test -v python
18: 'import perf' in python :
--- start ---
test child forked, pid 22364
test child finished with 0
---- end ----
'import perf' in python: Ok
#
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191108094128.28769-1-ravi.bangoria@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We got the sane_ctype.h headers from git and kept using it so far, but
since that code originally came from the kernel sources to the git
sources, perhaps its better to just use the one in the kernel, so that
we can leverage tools/perf/check_headers.sh to be notified when our copy
gets out of sync, i.e. when fixes or goodies are added to the code we've
copied.
This will help with things like tools/lib/string.c where we want to have
more things in common with the kernel, such as strim(), skip_spaces(),
etc so as to go on removing the things that we have in tools/perf/util/
and instead using the code in the kernel, indirectly and removing things
like EXPORT_SYMBOL(), etc, getting notified when fixes and improvements
are made to the original code.
Hopefully this also should help with reducing the difference of code
hosted in tools/ to the one in the kernel proper.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-7k9868l713wqtgo01xxygn12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding 'perf data convert' to convert perf data file into different
format. This patch adds support for CTF format conversion.
To convert perf.data into CTF run:
$ perf data convert --to-ctf=./ctf-data/
[ perf data convert: Converted 'perf.data' into CTF data './ctf-data/' ]
[ perf data convert: Converted and wrote 11.268 MB (100230 samples) ]
The command will create CTF metadata out of perf.data file (or one
specified via -i option) and then convert all sample events into single
CTF stream.
Each sample_type bit is translated into separated CTF event field apart
from following exceptions:
PERF_SAMPLE_RAW - added in next patch
PERF_SAMPLE_READ - TODO
PERF_SAMPLE_CALLCHAIN - TODO
PERF_SAMPLE_BRANCH_STACK - TODO
PERF_SAMPLE_REGS_USER - TODO
PERF_SAMPLE_STACK_USER - TODO
$ perf --debug=data-convert=2 data convert ...
The converted CTF data could be analyzed by CTF tools, like babletrace
or tracecompass [1].
$ babeltrace ./ctf-data/
[03:19:13.962125533] (+?.?????????) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 1 }
[03:19:13.962130001] (+0.000004468) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 1 }
[03:19:13.962131936] (+0.000001935) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 8 }
[03:19:13.962133732] (+0.000001796) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 114 }
[03:19:13.962135557] (+0.000001825) cycles: { }, { ip = 0xFFFFFFFF8105443A, tid = 20714, pid = 20714, period = 2087 }
[03:19:13.962137627] (+0.000002070) cycles: { }, { ip = 0xFFFFFFFF81361938, tid = 20714, pid = 20714, period = 37582 }
[03:19:13.962161091] (+0.000023464) cycles: { }, { ip = 0xFFFFFFFF8124218F, tid = 20714, pid = 20714, period = 600246 }
[03:19:13.962517569] (+0.000356478) cycles: { }, { ip = 0xFFFFFFFF811A75DB, tid = 20714, pid = 20714, period = 1325731 }
[03:19:13.969518008] (+0.007000439) cycles: { }, { ip = 0x34080917B2, tid = 20714, pid = 20714, period = 1144298 }
The following members to the ctf-environment were decided to be added to
distinguish and specify perf CTF data:
- domain
It says "kernel" because it contains a kernel trace (not to be
confused with a user space like lttng-ust does)
- tracer_name
It says perf. This can be used to distinguish between lttng and perf
CTF based trace.
- version
The kernel version from stream. In addition to release, this is what
it looks like on a Debian kernel:
release = "3.14-1-amd64";
version = "3.14.0";
[1] http://projects.eclipse.org/projects/tools.tracecompass
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1424470628-5969-4-git-send-email-jolsa@kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When debugging the tui browser I find it useful to redirect the debug
log into a file. Currently it's always forced to the message line.
Add an option to force it to stderr. Then it can be easily redirected.
Example:
[root@zoo ~]# perf --debug stderr report -vv 2> /tmp/debug
[root@zoo ~]# tail /tmp/debug
dso open failed, mmap: No such file or directory
dso open failed, mmap: No such file or directory
dso open failed, mmap: No such file or directory
dso open failed, mmap: No such file or directory
dso open failed, mmap: No such file or directory
Using /root/.debug/.build-id/4e/841948927029fb650132253642d5dbb2c1fb93 for symbols
Failed to open /tmp/perf-8831.map, continuing without symbols
Failed to open /tmp/perf-12721.map, continuing without symbols
Failed to open /tmp/perf-6966.map, continuing without symbols
Failed to open /tmp/perf-8802.map, continuing without symbols
[root@zoo ~]#
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1416605880-25055-2-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
