History log of /linux-master/tools/perf/Documentation/perf-data.txt
Revision Date Author Comments
# d0713d4c 26-Apr-2021 Nicholas Fraser <nfraser@codeweavers.com>

perf data: Add JSON export

This adds a feature to export perf data to JSON.

The resolved symbols are exported into the JSON so that external tools
don't need to load the dsos themselves (or even have access to them at
all.) This makes it easy to load and analyze perf data with standalone
tools where direct perf or libbabeltrace integration is impractical.

The exporter uses a minimal inline JSON encoding without any external
dependencies. Currently it only outputs some headers and sample metadata
but it's easily extensible.

Use it like this:

$ perf data convert --to-json out.json

Committer notes:

Fixup a __printf() bug that broke the build:

util/data-convert-json.c:103:11: error: expected ‘)’ before numeric constant
103 | __(printf, 5, 6)
| ^~
| )
util/data-convert-json.c: In function ‘output_sample_callchain_entry’:
util/data-convert-json.c:124:2: error: implicit declaration of function ‘output_json_key_format’; did you mean ‘output_json_format’? [-Werror=implicit-function-declaration]
124 | output_json_key_format(out, false, 5, "ip", "\"0x%" PRIx64 "\"", ip);
| ^~~~~~~~~~~~~~~~~~~~~~
| output_json_format

Also had to add this patch to fix errors reported by various versions of
clang:

- if (al && al->sym && al->sym->name && strlen(al->sym->name) > 0) {
+ if (al && al->sym && al->sym->namelen) {

al->sym->name is a zero sized array, to avoid one extra alloc in the
symbol__new() constructor, sym->namelen carries its strlen.

Committer testing:

$ ls -la out.json
ls: cannot access 'out.json': No such file or directory
$ perf record sleep 0.1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.001 MB perf.data (8 samples) ]
$ perf report --stats | grep -w SAMPLE
SAMPLE events: 8
$ perf data convert --to-json out.json
[ perf data convert: Converted 'perf.data' into JSON data 'out.json' ]
[ perf data convert: Converted and wrote 0.002 MB (8 samples) ]
$ ls -la out.json
-rw-rw-r--. 1 acme acme 2017 Apr 26 17:29 out.json
$ cat out.json
{
"linux-perf-json-version": 1,
"headers": {
"header-version": 1,
"captured-on": "2021-04-26T20:28:57Z",
"data-offset": 432,
"data-size": 1016,
"feat-offset": 1448,
"hostname": "five",
"os-release": "5.11.14-200.fc33.x86_64",
"arch": "x86_64",
"cpu-desc": "AMD Ryzen 9 3900X 12-Core Processor",
"cpuid": "AuthenticAMD,23,113,0",
"nrcpus-online": 24,
"nrcpus-avail": 24,
"perf-version": "5.12.gee134f3189bd",
"cmdline": [
"/home/acme/bin/perf",
"record",
"sleep",
"0.1"
]
},
"samples": [
{
"timestamp": 170517539043684,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0xffffffffa6268827"
}
]
},
{
"timestamp": 170517539048443,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0xffffffffa661359d"
}
]
},
{
"timestamp": 170517539051018,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0xffffffffa6311e18"
}
]
},
{
"timestamp": 170517539053652,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0x7fdb77b4812b",
"symbol": "_dl_start",
"dso": "ld-2.32.so"
}
]
},
{
"timestamp": 170517539055306,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0xffffffffa6269286"
}
]
},
{
"timestamp": 170517539057590,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0xffffffffa62abd8b"
}
]
},
{
"timestamp": 170517539067559,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0x7fdb77b5e9e9",
"symbol": "__GI___tunables_init",
"dso": "ld-2.32.so"
}
]
},
{
"timestamp": 170517539282452,
"pid": 375844,
"tid": 375844,
"comm": "sleep",
"callchain": [
{
"ip": "0x7fdb779978d2",
"symbol": "getenv",
"dso": "libc-2.32.so"
}
]
}
]
}
$

Signed-off-by: Nicholas Fraser <nfraser@codeweavers.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tan Xiaojun <tanxiaojun@huawei.com>
Cc: Ulrich Czekalla <uczekalla@codeweavers.com>
Link: http://lore.kernel.org/lkml/3884969f-804d-2f53-c648-e2b0bd85edff@codeweavers.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 88371c58 05-Aug-2020 Jiri Olsa <jolsa@kernel.org>

perf data: Add support to store time of day in CTF data conversion

Adad support to convert and store time of day in CTF data conversion for
'perf data convert' subcommand.

The perf.data used for conversion needs to have clock data information -
must be recorded with -k/--clockid option).

New --tod option is added to 'perf data convert' subcommand to convert
data with timestamps converted to wall clock time.

Record data with clockid set:

# perf record -k CLOCK_MONOTONIC kill
kill: not enough arguments
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.033 MB perf.data (8 samples) ]

Convert data with TOD timestamps:

# perf data convert --tod --to-ctf ./ctf
[ perf data convert: Converted 'perf.data' into CTF data './ctf' ]
[ perf data convert: Converted and wrote 0.000 MB (8 samples) ]

Display data in perf script:

# perf script -F+tod --ns
perf 262150 2020-07-13 18:38:50.097678523 153633.958246159: 1 cycles: ...
perf 262150 2020-07-13 18:38:50.097682941 153633.958250577: 1 cycles: ...
perf 262150 2020-07-13 18:38:50.097684997 153633.958252633: 7 cycles: ...
...

Display data in babeltrace:

# babeltrace --clock-date ./ctf
[2020-07-13 18:38:50.097678523] (+?.?????????) cycles: { cpu_id = 0 }, { perf_ip = 0xFFF ...
[2020-07-13 18:38:50.097682941] (+0.000004418) cycles: { cpu_id = 0 }, { perf_ip = 0xFFF ...
[2020-07-13 18:38:50.097684997] (+0.000002056) cycles: { cpu_id = 0 }, { perf_ip = 0xFFF ...
...

It's available only for recording with clockid specified, because it's
the only case where we can get reference time to wallclock time. It's
can't do that with perf clock yet.

Error is display if you want to use --tod on data without clockid
specified:

# perf data convert --tod --to-ctf ./ctf
Can't provide --tod time, missing clock data. Please record with -k/--clockid option.
Failed to setup CTF writer.
Error during conversion setup.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Geneviève Bastien <gbastien@versatic.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Jeremie Galarneau <jgalar@efficios.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lore.kernel.org/lkml/20200805093444.314999-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# ea66536a 07-Mar-2018 Takashi Iwai <tiwai@suse.de>

perf tools: Correct title markers for asciidoctor

I've tested to process the perf man pages with asciidoctor that is
picker than asciidoc, and it revealed minor syntax errors in some
documents. Namely, the title markers aren't aligned with the previous
line, hence asciidoctor didn't recognize as titles.

This patch corrects these markers to be processed properly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180307105441.28512-1-tiwai@suse.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# ba7e8516 05-Feb-2018 Sangwon Hong <qpakzk@gmail.com>

perf data: Document missing --force option

Add the --force option to the man page.

Signed-off-by: Sangwon Hong <qpakzk@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/r/1517831315-31490-1-git-send-email-qpakzk@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# 9e1a7ea1 24-Jun-2016 Wang Nan <wangnan0@huawei.com>

perf data ctf: Add '--all' option for 'perf data convert'

After this patch, 'perf data convert' convert comm events to output CTF
stream.

Result:

# perf record -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.378 MB perf.data (73 samples) ]

# perf data convert --to-ctf ./out.ctf
[ perf data convert: Converted 'perf.data' into CTF data './out.ctf' ]
[ perf data convert: Converted and wrote 0.003 MB (73 samples) ]

# babeltrace --clock-seconds ./out.ctf/
[10627.402515791] (+?.?????????) cycles:ppp: { cpu_id = 0 }, { perf_ip = 0xFFFFFFFF81065AF4, perf_tid = 0, perf_pid = 0, perf_period = 1 }
[10627.402518972] (+0.000003181) cycles:ppp: { cpu_id = 0 }, { perf_ip = 0xFFFFFFFF81065AF4, perf_tid = 0, perf_pid = 0, perf_period = 1 }
... // only sample event is converted

# perf data convert --all --to-ctf ./out.ctf
[ perf data convert: Converted 'perf.data' into CTF data './out.ctf' ]
[ perf data convert: Converted and wrote 0.023 MB (73 samples, 384 non-samples) ]

# babeltrace --clock-seconds ./out.ctf/
[ 0.000000000] (+?.?????????) perf_comm: { cpu_id = 0 }, { pid = 1, tid = 1, comm = "init" }
[ 0.000000000] (+0.000000000) perf_comm: { cpu_id = 0 }, { pid = 2, tid = 2, comm = "kthreadd" }
[ 0.000000000] (+0.000000000) perf_comm: { cpu_id = 0 }, { pid = 3, tid = 3, comm = "ksoftirqd/0" }
... // comm events are converted
[10627.402515791] (+10627.402515791) cycles:ppp: { cpu_id = 0 }, { perf_ip = 0xFFFFFFFF81065AF4, perf_tid = 0, perf_pid = 0, perf_period = 1 }
[10627.402518972] (+0.000003181) cycles:ppp: { cpu_id = 0 }, { perf_ip = 0xFFFFFFFF81065AF4, perf_tid = 0, perf_pid = 0, perf_period = 1 }
... // samples are also converted

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1466767332-114472-7-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>


# edbe9817 20-Feb-2015 Jiri Olsa <jolsa@kernel.org>

perf data: Add perf data to CTF conversion support

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>


# 2245bf14 20-Feb-2015 Jiri Olsa <jolsa@kernel.org>

perf tools: Add new 'perf data' command

Adding new 'perf data' command to provide operations over data files.

The 'perf data convert' sub command is coming in following patch, but
there's possibility for other useful commands like 'perf data ls' (to
display perf data file in directory in ls style).

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: David Ahern <dsahern@gmail.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/1424470628-5969-3-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>