Trace events have a period (weight) of 1 by default. This can be
overriden on events definition by using the __perf_count() macro.
For example, the sched_stat_runtime() is weighted with the runtime of
the task that fired the event.
By default, perf handles such weighted event by dividing it into
individual events carrying a weight of 1. For example if
sched_stat_runtime is fired and the task has run 5000000 nsecs, perf
divides it into 5000000 events in the buffer.
This behaviour makes weighted events unusable because they quickly
fullfill the buffers and we lose most events.
The commit 5d81e5cfb3 ("events: Don't
divide events if it has field period") solves this problem by sending
only one event when PERF_SAMPLE_PERIOD flag is set. The weight is
carried in the sample itself such that we don't need to demultiplex it
anymore.
This patch provides the last missing piece to use this feature by
setting PERF_SAMPLE_PERIOD from perf tools when we deal with trace
events.
Before:
$ ./perf record -e sched:* -a sleep 1
[ perf record: Woken up 3 times to write data ]
[ perf record: Captured and wrote 1.619 MB perf.data (~70749 samples) ]
Warning:
Processed 16909 events and lost 1 chunks!
Check IO/CPU overload!
$ ./perf script
perf 1894 [003] 824.898327: sched_migrate_task: comm=perf pid=1898 prio=120 orig_cpu=2 dest_cpu=0
perf 1894 [003] 824.898335: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898336: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898337: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898338: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898339: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898340: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
perf 1894 [003] 824.898341: sched_stat_sleep: comm=perf pid=1898 delay=113179500 [ns]
[...]
After:
$ ./perf record -e sched:* -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.074 MB perf.data (~3228 samples) ]
$ ./perf script
perf 1461 [000] 554.286957: sched_migrate_task: comm=perf pid=1465 prio=120 orig_cpu=3 dest_cpu=1
perf 1461 [000] 554.286964: sched_stat_sleep: comm=perf pid=1465 delay=133047190 [ns]
perf 1461 [000] 554.286967: sched_wakeup: comm=perf pid=1465 prio=120 success=1 target_cpu=001
swapper 0 [001] 554.286976: sched_stat_wait: comm=perf pid=1465 delay=0 [ns]
swapper 0 [001] 554.286983: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=perf
[...]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342631456-7233-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Guest kernel symbols are not resolved despite passing the information
needed to resolve them. e.g.,
perf kvm --guest --guestmount=/tmp/guest-mount record -a -- sleep 1
perf kvm --guest --guestmount=/tmp/guest-mount report --stdio
36.55% [guest/11399] [unknown] [g] 0xffffffff81600bc8
33.19% [guest/10474] [unknown] [g] 0x00000000c0116e00
30.26% [guest/11094] [unknown] [g] 0xffffffff8100a288
43.69% [guest/10474] [unknown] [g] 0x00000000c0103d90
37.38% [guest/11399] [unknown] [g] 0xffffffff81600bc8
12.24% [guest/11094] [unknown] [g] 0xffffffff810aa91d
6.69% [guest/11094] [unknown] [u] 0x00007fa784d721c3
which is just pathetic.
After a maddening 2 days sifting through perf minutia I found it --
id_hdr_size is not initialized for guest machines. This shows up on the
report side as random garbage for the cpu and timestamp, e.g.,
29816 7310572949125804849 0x1ac0 [0x50]: PERF_RECORD_MMAP ...
That messes up the sample sorting such that synthesized guest maps are
processed last.
With this patch you get a much more helpful report:
12.11% [guest/11399] [guest.kernel.kallsyms.11399] [g] irqtime_account_process_tick
10.58% [guest/11399] [guest.kernel.kallsyms.11399] [g] run_timer_softirq
6.95% [guest/11094] [guest.kernel.kallsyms.11094] [g] printk_needs_cpu
6.50% [guest/11094] [guest.kernel.kallsyms.11094] [g] do_timer
6.45% [guest/11399] [guest.kernel.kallsyms.11399] [g] idle_balance
4.90% [guest/11094] [guest.kernel.kallsyms.11094] [g] native_read_tsc
...
v2:
- changed rbtree walk to use rb_first per Namhyung's suggestion
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
COMM events are not generated in the context of a guest machine, so the
thread name is never set for the VMM process. For example, the qemu-kvm
name applies to the process in the host machine, not the guest machine.
So, samples for guest machines are currently displayed as:
99.67% :5671 [unknown] [g] 0xffffffff81366b41
where 5671 is the pid of the VMM. With this patch the samples in the guest
machine are shown as:
18.43% [guest/5671] [unknown] [g] 0xffffffff810d68b7
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1342826756-64663-3-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf/core improvements and fixes:
- Preparatory patches to use hw events in PMU syntax, from Jiri Olsa
- Remaining backport of trace-cmd's libparseevent, from Namhyung Kim
- Fix libtraceevent 'clean' make target, from Namhyung Kim
- Teach ctags about libtraceevent error codes, from Namhyung Kim
- Fix libtraceevent dependency files usage, from Namhyung Kim
- Support hex number pretty printing in libtraceevent, fixing
kvm output, from Namhyung Kim
- Kill some die() usage in libtraceevent, from Namhyung Kim
- Improve support for hw breakpoints parsing/pretty printing/testing,
from Jiri Olsa
- Clarify perf bench option naming, from Hitoshi Mitake
- Look for ".note" ELF notes too, used in the kernel vdso, from Jiri Olsa
- Fix internal PMU list usage, removing leak, from Robert Richter
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The __read_token() function has some duplicated code to handle
internal buffer overflow. Factor them out to new extend_token().
According to the man pages of realloc/free(3), they can handle NULL
pointer input so that it can be ended up to compact the code. Also
handle error path correctly.
Signed-off-by: Namhyung Kim <namhyung.kim@lge.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1333940074-19052-4-git-send-email-namhyung.kim@lge.com
[rostedt@goodmis.org: added some extra whitespace]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
On 32 bit systems, a conversion of the trace_printk format string
"%lu" -> "%llu" is intended (similar for %lx etc.) when a trace was
taken on a machine with 64 bit long integers. However, the current
code computes the bogus transformation "%lu" -> "%u". Fix this.
Besides that, the transformation is only required on systems that don't
use 64 bits for long integers natively.
Signed-off-by: Wolfgang Mauerer <wolfgang.mauerer@siemens.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1332411501-8059-3-git-send-email-wolfgang.mauerer@siemens.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
When %pM is used, the arg value must be a 6 byte character that will
be printed as a 6 byte MAC address. But the code does a break over the
main code which updates the current processing arg to point to the
next arg. If there are other print arguments after a %pM, they will be
off by one. The next arg will still be processing the %pM arg.
Reported-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-q3g0n1espikynsdkpbi6ue6t@git.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
As a pointer can be converted into a function name, let the filters
work with the function name as well as with the pointer number. If
the comparison expects a string, then convert numbers into functions,
but only when the number is the same size as a long.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-oxsa1qkr2eq7u8d7r0aapedu@git.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
As Namhyung Kim pointed, there are confused namings and descriptions of words
"cycle" and "clock" in mem-memset.c and mem-memcpy.c.
With the option "-c" (or "--clock", now renamed as "--cycle"), mem subsystem
measures cost of memset() and memcpy() with cpu-cycles event.
But current mem subsystem source code contains lots of confused variable
namings and descriptions with "clock" (e.g. the variable use_clock). This is a
very bad style because there is another software event named "cpu-clock". This
patch replaces wrong usage of "clock" to "cycle".
v2: modified Documentation/perf-bench.txt for the descriptions of
--cycle option
Signed-off-by: Hitoshi Mitake <h.mitake@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1341236777-18457-1-git-send-email-h.mitake@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Using the guestmount option on record:
$ perf kvm --guest --host --guestmount=/tmp/guest-mount record -ag
But not the subsequent report:
$ perf kvm report
causes a SEGFAULT in the usual place:
(gdb) bt
0 0x0000000000470356 in machine__mmap_name (self=0x0, bf=0x7fffffffbdb0 " z\370\367\377\177", size=
4096) at util/map.c:712
1 0x00000000004453e8 in perf_event__process_kernel_mmap (tool=0x7fffffffde10, event=0x7ffff7f87e38,
machine=0x0) at util/event.c:550
2 0x00000000004458c9 in perf_event__process_mmap (tool=0x7fffffffde10, event=0x7ffff7f87e38, sample=
0x7fffffffd2a0, machine=0x0) at util/event.c:656
3 0x00000000004733e0 in perf_session_deliver_event (session=0x91aca0, event=0x7ffff7f87e38, sample=
0x7fffffffd2a0, tool=0x7fffffffde10, file_offset=7736) at util/session.c:979
...
The MMAP events in this case already contain the full path to the
module. No need to require it for the report path to.
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1341241977-71535-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 743eb86865 reworked when the
machines were created. Prior to this commit guest machines could be
created in perf_event__process_kernel_mmap() while processing kernel
MMAP events. This commit assumes that the machines exist by the time
perf_session_deliver_event is called (e.g., during processing of build
id events) - which is not always correct.
One example is the use of default guest args (--guestkallsyms and
--guestmodules) for short times where no samples hit within a guest
module. For this case no build id is added to the file header. No build
id == no machine created. That leads to the next example -- the use of
no-buildid (-B) on the record for all perf-kvm invocations. In both
cases perf report dies with a SEGFAULT of the form:
(gdb) bt
0 0x000000000046dd7b in machine__mmap_name (self=0x0, bf=0x7fffffffbd20 "q\021", size=4096) at util/map.c:715
1 0x0000000000444161 in perf_event__process_kernel_mmap (tool=0x7fffffffdd80, event=0x7ffff7fb4120, machine=0x0) at util/event.c:562
2 0x0000000000444642 in perf_event__process_mmap (tool=0x7fffffffdd80, event=0x7ffff7fb4120, sample=0x7fffffffd210, machine=0x0)
at util/event.c:668
3 0x0000000000470e0b in perf_session_deliver_event (session=0x915ca0, event=0x7ffff7fb4120, sample=0x7fffffffd210, tool=0x7fffffffdd80,
file_offset=8480) at util/session.c:979
4 0x000000000047032e in flush_sample_queue (s=0x915ca0, tool=0x7fffffffdd80) at util/session.c:679
5 0x0000000000471c8d in __perf_session__process_events (session=0x915ca0, data_offset=400, data_size=150448, file_size=150848, tool=
0x7fffffffdd80) at util/session.c:1363
6 0x0000000000471d42 in perf_session__process_events (self=0x915ca0, tool=0x7fffffffdd80) at util/session.c:1379
7 0x000000000042484a in __cmd_report (rep=0x7fffffffdd80) at builtin-report.c:368
8 0x0000000000425bf1 in cmd_report (argc=0, argv=0x915b00, prefix=0x0) at builtin-report.c:756
9 0x0000000000438505 in __cmd_report (argc=4, argv=0x7fffffffe260) at builtin-kvm.c:84
10 0x000000000043882a in cmd_kvm (argc=4, argv=0x7fffffffe260, prefix=0x0) at builtin-kvm.c:131
11 0x00000000004152cd in run_builtin (p=0x7a54e8, argc=9, argv=0x7fffffffe260) at perf.c:273
12 0x00000000004154c7 in handle_internal_command (argc=9, argv=0x7fffffffe260) at perf.c:345
13 0x0000000000415613 in run_argv (argcp=0x7fffffffe14c, argv=0x7fffffffe140) at perf.c:389
14 0x0000000000415899 in main (argc=9, argv=0x7fffffffe260) at perf.c:487
Fix by allowing the machine to be created in perf_session_deliver_event.
Tested with --guestmount option and default guest args, with and without
-B arg on record for both and for short (10 seconds) and long (10
minutes) windows.
Reported-by: Pradeep Kumar Surisetty <psuriset@linux.vnet.ibm.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pradeep Kumar Surisetty <psuriset@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1341180697-64515-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Consider the commands:
perf record -e sched:sched_switch -fo /tmp/perf.data -a -- sleep 1
perf script -i /tmp/perf.data
In v3.4 the output has the form (lines wrapped here)
perf 29214 [005] 821043.582596: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
In 3.5 that same line has become:
perf 29214 [005] 821043.582596: sched_switch:
<...>-29214 [005] 0.000000000: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
Note the duplicates in the output -- pid, cpu, event name. With
this patch the v3.4 output is restored:
perf 29214 [005] 821043.582596: sched_switch:
prev_comm=perf prev_pid=29214 prev_prio=120
prev_state=S ==> next_comm=swapper/5 next_pid=0 next_prio=120
v3:
Remove that pesky newline too. Output now matches v3.4 (pre-libtracevent).
v2:
Change print_trace_event function local to perf per Steve's comments.
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1339698977-68962-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When libtraceevent parses format fields, it assumes that array of 1 byte
is string but it's not always true. The kvm_emulate_insn contains 15 u8
array of insn that contains (binary) instructions. Thus when it's
printed, it'll have broken output like below:
kvm_emulate_insn: [FAILED TO PARSE] rip=3238197797 csbase=0 len=2 \
insn=<89>P^]<B4>& flags=5 failed=0
With this patch:
kvm_emulate_insn: [FAILED TO PARSE] rip=3238197797 csbase=0 len=2 \
insn=ARRAY[89, 10, 5d, c3, 8d, b4, 26, 00, 00, 00, 00, 55, 89, e5, 3e] flags=5 failed=0
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1340352615-20737-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>