AUX area traces can produce too much data to record successfully or
analyze subsequently. Add another means to reduce data collection by
allowing multiple recording time ranges.
This is useful, for instance, in cases where a workload produces
predictably reproducible events in specific time ranges.
Today we only have perf record -D <msecs> to start at a specific region, or
some complicated approach using snapshot mode and external scripts sending
signals or using the fifos. But these approaches are difficult to set up
compared with simply having perf do it.
Extend perf record option -D/--delay option to specifying relative time
stamps for start stop controlled by perf with the right time offset, for
instance:
perf record -e intel_pt// -D 10-20,30-40
to record 10ms to 20ms into the trace and 30ms to 40ms.
Example:
The example workload is:
$ cat repeat-usleep.c
int usleep(useconds_t usec);
int usage(int ret, const char *msg)
{
if (msg)
fprintf(stderr, "%s\n", msg);
fprintf(stderr, "Usage is: repeat-usleep <microseconds>\n");
return ret;
}
int main(int argc, char *argv[])
{
unsigned long usecs;
char *end_ptr;
if (argc != 2)
return usage(1, "Error: Wrong number of arguments!");
errno = 0;
usecs = strtoul(argv[1], &end_ptr, 0);
if (errno || *end_ptr || usecs > UINT_MAX)
return usage(1, "Error: Invalid argument!");
while (1) {
int ret = usleep(usecs);
if (ret & errno != EINTR)
return usage(1, "Error: usleep() failed!");
}
return 0;
}
$ perf record -e intel_pt//u --delay 10-20,40-70,110-160 -- ./repeat-usleep 500
Events disabled
Events enabled
Events disabled
Events enabled
Events disabled
Events enabled
Events disabled
[ perf record: Woken up 5 times to write data ]
[ perf record: Captured and wrote 0.204 MB perf.data ]
Terminated
A dlfilter is used to determine continuous data collection (timestamps
less than 1ms apart):
$ cat dlfilter-show-delays.c
static __u64 start_time;
static __u64 last_time;
int start(void **data, void *ctx)
{
printf("%-17s\t%-9s\t%-6s\n", " Time", " Duration", " Delay");
return 0;
}
int filter_event_early(void *data, const struct perf_dlfilter_sample *sample, void *ctx)
{
__u64 delta;
if (!sample->time)
return 1;
if (!last_time)
goto out;
delta = sample->time - last_time;
if (delta < 1000000)
goto out2;;
printf("%17.9f\t%9.1f\t%6.1f\n", start_time / 1000000000.0, (last_time - start_time) / 1000000.0, delta / 1000000.0);
out:
start_time = sample->time;
out2:
last_time = sample->time;
return 1;
}
int stop(void *data, void *ctx)
{
printf("%17.9f\t%9.1f\n", start_time / 1000000000.0, (last_time - start_time) / 1000000.0);
return 0;
}
The result shows the times roughly match the --delay option:
$ perf script --itrace=qb --dlfilter dlfilter-show-delays.so
Time Duration Delay
39215.302317300 9.7 20.5
39215.332480217 30.4 40.9
39215.403837717 49.8
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220824072814.16422-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Current perf stat uses the evlist__add_default_attrs() to add the
generic default attrs, and uses arch_evlist__add_default_attrs() to add
the Arch specific default attrs, e.g., Topdown for x86.
It works well for the non-hybrid platforms. However, for a hybrid
platform, the hard code generic default attrs don't work.
Uses arch_evlist__add_default_attrs() to replace the
evlist__add_default_attrs(). The arch_evlist__add_default_attrs() is
modified to invoke the same __evlist__add_default_attrs() for the
generic default attrs. No functional change.
Add default_null_attrs[] to indicate the arch specific attrs.
No functional change for the arch specific default attrs either.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220721065706.2886112-4-zhengjun.xing@linux.intel.com
Signed-off-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In previous patch, we have supported the syntax which enables
the event on a specified pmu, such as:
cpu_core/<event>/
cpu_atom/<event>/
While this syntax is not very easy for applying on a set of
events or applying on a group. In following example, we have to
explicitly assign the pmu prefix.
# ./perf stat -e '{cpu_core/cycles/,cpu_core/instructions/}' -- sleep 1
Performance counter stats for 'sleep 1':
1,158,545 cpu_core/cycles/
1,003,113 cpu_core/instructions/
1.002428712 seconds time elapsed
A much easier way is:
# ./perf stat --cputype core -e '{cycles,instructions}' -- sleep 1
Performance counter stats for 'sleep 1':
1,101,071 cpu_core/cycles/
939,892 cpu_core/instructions/
1.002363142 seconds time elapsed
For this example, the '--cputype' enables the events from specified
pmu (cpu_core).
If '--cputype' conflicts with pmu prefix, '--cputype' is ignored.
# ./perf stat --cputype core -e cycles,cpu_atom/instructions/ -a -- sleep 1
Performance counter stats for 'system wide':
21,003,407 cpu_core/cycles/
367,886 cpu_atom/instructions/
1.002203520 seconds time elapsed
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210909062215.10278-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently topdown events must appear after a slots event:
$ perf stat -e '{slots,topdown-fe-bound}' /bin/true
Performance counter stats for '/bin/true':
3,183,090 slots
986,133 topdown-fe-bound
Reversing the events yields:
$ perf stat -e '{topdown-fe-bound,slots}' /bin/true
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (topdown-fe-bound).
For metrics the order of events is determined by iterating over a
hashmap, and so slots isn't guaranteed to be first which can yield this
error.
Change the set_leader in parse-events, called when a group is closed, so
that rather than always making the first event the leader, if the slots
event exists then it is made the leader. It is then moved to the head of
the evlist otherwise it won't be opened in the correct order.
The result is:
$ perf stat -e '{topdown-fe-bound,slots}' /bin/true
Performance counter stats for '/bin/true':
3,274,795 slots
1,001,702 topdown-fe-bound
A problem with this approach is the slots event is identified by name,
names can be overwritten like 'cpu/slots,name=foo/' and this causes the
leader change to fail.
The change also modifies and fixes mixed groups like, with the change:
$ perf stat -e '{instructions,slots,topdown-fe-bound}' -a -- sleep 2
Performance counter stats for 'system wide':
5574985410 slots
971981616 instructions
1348461887 topdown-fe-bound
2.001263120 seconds time elapsed
Without the change:
$ perf stat -e '{instructions,slots,topdown-fe-bound}' -a -- sleep 2
Performance counter stats for 'system wide':
<not counted> instructions
<not counted> slots
<not supported> topdown-fe-bound
2.006247990 seconds time elapsed
Something that may be undesirable here is that the events are reordered
in the output.
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Link: http://lore.kernel.org/lkml/20211130174945.247604-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit da231338ec ("perf record: Use an eventfd to wakeup when
done") uses eventfd() to solve a rare race where the setting and
checking of 'done' which add done_fd to pollfd. When draining buffer,
revents of done_fd is 0 and evlist__filter_pollfd function returns a
non-zero value. As a result, perf record does not stop profiling.
The following simple scenarios can trigger this condition:
# sleep 10 &
# perf record -p $!
After the sleep process exits, perf record should stop profiling and exit.
However, perf record keeps running.
If pollfd revents contains only POLLERR or POLLHUP, perf record
indicates that buffer is draining and need to stop profiling. Use
fdarray_flag__nonfilterable() to set done eventfd to nonfilterable
objects, so that evlist__filter_pollfd() does not filter and check done
eventfd.
Fixes: da231338ec ("perf record: Use an eventfd to wakeup when done")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: zhangjinhao2@huawei.com
Link: http://lore.kernel.org/lkml/20210205065001.23252-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The Topdown Microarchitecture Analysis (TMA) Method is a structured
analysis methodology to identify critical performance bottlenecks in
out-of-order processors. From the Ice Lake and later platforms, the
Topdown information can be retrieved from the dedicated "metrics"
register, which isn't impacted by other events. Also, the Topdown
metrics support both per thread/process and per core measuring. Adding
Topdown metrics events as default events can enrich the default
measuring information, and would not cost any extra multiplexing.
Introduce arch_evlist__add_default_attrs() to allow architecture
specific default events. Add the Topdown metrics events in the X86
specific arch_evlist__add_default_attrs(). Other architectures can add
their own default events later separately.
With the patch:
$ perf stat sleep 1
Performance counter stats for 'sleep 1':
0.82 msec task-clock:u # 0.001 CPUs utilized
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
61 page-faults:u # 0.074 M/sec
319,941 cycles:u # 0.388 GHz
242,802 instructions:u # 0.76 insn per cycle
54,380 branches:u # 66.028 M/sec
4,043 branch-misses:u # 7.43% of all branches
1,585,555 slots:u # 1925.189 M/sec
238,941 topdown-retiring:u # 15.0% retiring
410,378 topdown-bad-spec:u # 25.8% bad speculation
634,222 topdown-fe-bound:u # 39.9% frontend bound
304,675 topdown-be-bound:u # 19.2% backend bound
1.001791625 seconds time elapsed
0.000000000 seconds user
0.001572000 seconds sys
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20210121133752.118327-1-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a new 'evlist' control command to display all the evlist events.
When it is received, perf will scan and print current evlist into perf
record terminal.
The interface string for control file is:
evlist [-v|-g|-F]
The syntax follows perf evlist command:
-F Show just the sample frequency used for each event.
-v Show all fields.
-g Show event group information.
Example session:
terminal 1:
# mkfifo control ack
# perf record --control=fifo:control,ack -e '{cycles,instructions}'
terminal 2:
# echo evlist > control
terminal 1:
cycles
instructions
dummy:HG
terminal 2:
# echo 'evlist -v' > control
terminal 1:
cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: \
IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, freq: 1, \
sample_id_all: 1, exclude_guest: 1
instructions: size: 120, config: 0x1, { sample_period, sample_freq }: 4000, \
sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, inherit: 1, freq: 1, \
sample_id_all: 1, exclude_guest: 1
dummy:HG: type: 1, size: 120, config: 0x9, { sample_period, sample_freq }: 4000, \
sample_type: IP|TID|TIME|ID|CPU|PERIOD, read_format: ID, inherit: 1, mmap: 1, \
comm: 1, freq: 1, task: 1, sample_id_all: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, \
bpf_event: 1
terminal 2:
# echo 'evlist -g' > control
terminal 1:
{cycles,instructions}
dummy:HG
terminal 2:
# echo 'evlist -F' > control
terminal 1:
cycles: sample_freq=4000
instructions: sample_freq=4000
dummy:HG: sample_freq=4000
This new evlist command is handy to get real event names when
wildcards are used.
Adding evsel_fprintf.c object to python/perf.so build, because
it's now evlist.c dependency.
Adding PYTHON_PERF define for python/perf.so compilation, so we
can use it to compile in only evsel__fprintf from evsel_fprintf.c
object.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@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: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201226232038.390883-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add 'snapshot' control command to create an AUX area tracing snapshot
the same as if sending SIGUSR2. The advantage of the FIFO is that access
is governed by access to the FIFO.
Example:
$ mkfifo perf.control
$ mkfifo perf.ack
$ cat perf.ack &
[1] 15235
$ sudo ~/bin/perf record --control fifo:perf.control,perf.ack -S -e intel_pt//u -- sleep 60 &
[2] 15243
$ ps -e | grep perf
15244 pts/1 00:00:00 perf
$ kill -USR2 15244
bash: kill: (15244) - Operation not permitted
$ echo snapshot > perf.control
ack
$
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200901093758.32293-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>