Document some features for specifying events in the perf list manpage:
- Event groups
- Leader sampling
- How to specify raw PMU events in the new syntax
- Global versus per process PMUs.
- Access restrictions
- Fix Intel SDM URL
v2: Lots of new content. address review feedback.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/1459810686-15913-1-git-send-email-andi@firstfloor.org
[ Add quotes to some keywords, such as "any" ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This ended up triggering these warnings when building on Ubuntu 12.04.5:
util/scripting-engines/trace-event-perl.c: In function 'perl_process_callchain':
util/scripting-engines/trace-event-perl.c:293:4: error: value computed is not used [-Werror=unused-value]
util/scripting-engines/trace-event-perl.c:294:4: error: value computed is not used [-Werror=unused-value]
util/scripting-engines/trace-event-perl.c:295:4: error: value computed is not used [-Werror=unused-value]
util/scripting-engines/trace-event-perl.c:297:4: error: value computed is not used [-Werror=unused-value]
util/scripting-engines/trace-event-perl.c:309:4: error: value computed is not used [-Werror=unused-value]
cc1: all warnings being treated as errors
mv: cannot stat `/tmp/build/perf/util/scripting-engines/.trace-event-perl.o.tmp': No such file or directory
make[4]: *** [/tmp/build/perf/util/scripting-engines/trace-event-perl.o] Error 1
Fix it by doing error checking when building the perl data structures
related to callchains.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@gmail.com>
Fixes: f7380c12ec ("perf script perl: Perl scripts now get a backtrace, like the python ones")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Do not use events that don't have timestamps when setting 'perf trace's
base timestamp, fixing up the timestamp column for syscalls (Arnaldo Carvalho de Melo)
- Make the 'bpf-output' sample_type be the same as tracepoint's, fixing up
'perf trace's timestamp column for bpf events (Wang Nan)
- Fix PMU term format max value calculation (Kan Liang)
- Pretty print 'seccomp', 'getrandom' syscalls in 'perf trace' (Arnaldo Carvalho de Melo)
Infrastructure changes:
- Add support for using TSC as an ARCH timestamp when synthesizing
JIT records (Adrian Hunter)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently the max value of format is calculated by the bits number. It
relies on the continuity of the format.
However, uncore event format is not continuous. E.g. uncore qpi event
format can be 0-7,21.
If bit 21 is set, there is parsing issues as below.
$ perf stat -a -e uncore_qpi_0/event=0x200002,umask=0x8/
event syntax error: '..pi_0/event=0x200002,umask=0x8/'
\___ value too big for format, maximum is 511
This patch return the real max value by setting all possible bits to 1.
Signed-off-by: Kan Liang <kan.liang@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1459365375-14285-1-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Intel PT uses the time members from the perf_event_mmap_page to convert
between TSC and perf time.
Due to a lack of foresight when Intel PT was implemented, those time
members were recorded in the (implementation dependent) AUXTRACE_INFO
event, the structure of which is generally inaccessible outside of the
Intel PT decoder. However now the conversion between TSC and perf time
is needed when processing a jitdump file when Intel PT has been used for
tracing.
So add a user event to record the time members. 'perf record' will
synthesize the event if the information is available. And session
processing will put a copy of the event on the session so that tools
like 'perf inject' can easily access it.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1457426324-30158-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Convert perf_output_begin() to __perf_output_begin() and make the later
function able to write records from the end of the ring-buffer.
Following commits will utilize the 'backward' flag.
This is the core patch to support writing to the ring-buffer backwards,
which will be introduced by upcoming patches to support reading from
overwritable ring-buffers.
In theory, this patch should not introduce any extra performance
overhead since we use always_inline, but it does not hurt to double
check that assumption:
When CONFIG_OPTIMIZE_INLINING is disabled, the output object is nearly
identical to original one. See:
http://lkml.kernel.org/g/56F52E83.70409@huawei.com
When CONFIG_OPTIMIZE_INLINING is enabled, the resuling object file becomes
smaller:
$ size kernel/events/ring_buffer.o*
text data bss dec hex filename
4641 4 8 4653 122d kernel/events/ring_buffer.o.old
4545 4 8 4557 11cd kernel/events/ring_buffer.o.new
Performance testing results:
Calling 3000000 times of 'close(-1)', use gettimeofday() to check
duration. Use 'perf record -o /dev/null -e raw_syscalls:*' to capture
system calls. In ns.
Testing environment:
CPU : Intel(R) Core(TM) i7-4790 CPU @ 3.60GHz
Kernel : v4.5.0
MEAN STDVAR
BASE 800214.950 2853.083
PRE 2253846.700 9997.014
POST 2257495.540 8516.293
Where 'BASE' is pure performance without capturing. 'PRE' is test
result of pure 'v4.5.0' kernel. 'POST' is test result after this
patch.
Considering the stdvar, this patch doesn't hurt performance, within
noise margin.
For testing details, see:
http://lkml.kernel.org/g/56F89DCD.1040202@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <pi3orama@163.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1459147292-239310-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current implementation aside of being an incomprehensible mess is broken.
# cat /sys/bus/event_source/devices/cstate_core/cpumask
0-17
That's on a quad socket machine with 72 physical cores! Qualitee stuff.
So it's not a surprise that event migration in case of CPU hotplug does not
work either.
# perf stat -e cstate_core/c6-residency/ -C 1 sleep 60 &
# echo 0 >/sys/devices/system/cpu/cpu1/online
Tracing cstate_pmu_event_update gives me:
[001] cstate_pmu_event_update <-event_sched_out
After the fix it properly moves the event:
[001] cstate_pmu_event_update <-event_sched_out
[073] cstate_pmu_event_update <-__perf_event_read
[073] cstate_pmu_event_update <-event_sched_out
The migration of pkg events does not work either. Not that I'm surprised.
I really could not be bothered to decode that loop mess and simply replaced it
by querying the proper cpumasks which give us the answer in a comprehensible
way.
This also requires to direct the event to the current active reader CPU in
cstate_pmu_event_init() otherwise the hotplug logic can't work.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ Added event->cpu < 0 test to not explode]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20160320185623.422519970@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Stephane reported that commit:
3cbaa59069 ("perf: Fix ctx time tracking by introducing EVENT_TIME")
introduced a regression wrt. time tracking, as easily observed by:
> This patch introduce a bug in the time tracking of events when
> multiplexing is used.
>
> The issue is easily reproducible with the following perf run:
>
> $ perf stat -a -C 0 -e branches,branches,branches,branches,branches,branches -I 1000
> 1.000730239 652,394 branches (66.41%)
> 1.000730239 597,809 branches (66.41%)
> 1.000730239 593,870 branches (66.63%)
> 1.000730239 651,440 branches (67.03%)
> 1.000730239 656,725 branches (66.96%)
> 1.000730239 <not counted> branches
>
> One branches event is shown as not having run. Yet, with
> multiplexing, all events should run especially with a 1s (-I 1000)
> interval. The delta for time_running comes out to 0. Yet, the event
> has run because the kernel is actually multiplexing the events. The
> problem is that the time tracking is the kernel and especially in
> ctx_sched_out() is wrong now.
>
> The problem is that in case that the kernel enters ctx_sched_out() with the
> following state:
> ctx->is_active=0x7 event_type=0x1
> Call Trace:
> [<ffffffff813ddd41>] dump_stack+0x63/0x82
> [<ffffffff81182bdc>] ctx_sched_out+0x2bc/0x2d0
> [<ffffffff81183896>] perf_mux_hrtimer_handler+0xf6/0x2c0
> [<ffffffff811837a0>] ? __perf_install_in_context+0x130/0x130
> [<ffffffff810f5818>] __hrtimer_run_queues+0xf8/0x2f0
> [<ffffffff810f6097>] hrtimer_interrupt+0xb7/0x1d0
> [<ffffffff810509a8>] local_apic_timer_interrupt+0x38/0x60
> [<ffffffff8175ca9d>] smp_apic_timer_interrupt+0x3d/0x50
> [<ffffffff8175ac7c>] apic_timer_interrupt+0x8c/0xa0
>
> In that case, the test:
> if (is_active & EVENT_TIME)
>
> will be false and the time will not be updated. Time must always be updated on
> sched out.
Fix this by always updating time if EVENT_TIME was set, as opposed to
only updating time when EVENT_TIME changed.
Reported-by: Stephane Eranian <eranian@google.com>
Tested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Cc: namhyung@kernel.org
Fixes: 3cbaa59069 ("perf: Fix ctx time tracking by introducing EVENT_TIME")
Link: http://lkml.kernel.org/r/20160329072644.GB3408@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf/core improvements and fixes:
User visible changes:
- Add support for skipping itrace instructions, useful to fast forward
processor trace (Intel PT, BTS) to right after initialization code at the start
of a workload (Andi Kleen)
- Add support for backtraces in perl 'perf script's (Dima Kogan)
- Add -U/-K (--all-user/--all-kernel) options to 'perf mem' (Jiri Olsa)
- Make -f/--force option documentation consistent across tools (Jiri Olsa)
Infrastructure changes:
- Add 'perf test' to check for event times (Jiri Olsa)
- 'perf config' cleanups (Taeung Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
- Fix determination of a callchain node's childlessness in
the top/report TUI, which was preventing navigating some
callchains, --stdio unnaffected (Andres Freund)
- Fix jitdump's genelf assumption that PowerPC is big endian
only (Anton Blanchard)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The 4b3a321223 ("perf hists browser: Support flat callchains") commit
over-aggressively tried to optimize callchain_node__init_have_children().
That lead to --tui mode not allowing to expand call chain elements if a
call chain element had only one parent. That's why --inverted callgraphs
looked halfway sane, but plain ones didn't.
Revert that individual optimization, it wasn't really related to the
rest of the commit.
Signed-off-by: Andres Freund <andres@anarazel.de>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fixes: 4b3a321223 ("perf hists browser: Support flat callchains")
Link: http://lkml.kernel.org/r/20160330190245.GB13305@awork2.anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When using 'perf script' to look at PT traces it is often useful to
ignore the initialization code at the beginning.
On larger traces which may have many millions of instructions in
initialization code doing that in a pipeline can be very slow, with perf
script spending a lot of CPU time calling printf and writing data.
This patch adds an extension to the --itrace argument that skips 'n'
events (instructions, branches or transactions) at the beginning. This
is much more efficient.
v2:
Add support for BTS (Adrian Hunter)
Document in itrace.txt
Fix branch check
Check transactions and instructions too
Committer note:
To test intel_pt one needs to make sure VT-x isn't active, i.e.
stopping KVM guests on the test machine, as described by Andi Kleen
at http://lkml.kernel.org/r/20160301234953.GD23621@tassilo.jf.intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1459187142-20035-1-git-send-email-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We have some infrastructure to use perl or python to analyze logs
generated by perf. Prior to this patch, only the python tools had
access to backtrace information. This patch makes this information
available to perl scripts as well. Example:
Let's look at malloc() calls made by the seq utility. First we
create a probe point:
$ perf probe -x /lib/x86_64-linux-gnu/libc.so.6 malloc
Added new events:
...
Now we run seq, while monitoring malloc() calls with perf
$ perf record --call-graph=dwarf -e probe_libc:malloc seq 5
1
2
3
4
5
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.064 MB perf.data (6 samples) ]
We can use perf to look at its log to see the malloc calls and the backtrace
$ perf script
seq 14195 [000] 1927993.748254: probe_libc:malloc: (7f9ff8edd320) bytes=0x22
7f9ff8edd320 malloc (/lib/x86_64-linux-gnu/libc-2.22.so)
7f9ff8e8eab0 set_binding_values.part.0 (/lib/x86_64-linux-gnu/libc-2.22.so)
7f9ff8e8eda1 __bindtextdomain (/lib/x86_64-linux-gnu/libc-2.22.so)
401b22 main (/usr/bin/seq)
7f9ff8e82610 __libc_start_main (/lib/x86_64-linux-gnu/libc-2.22.so)
402799 _start (/usr/bin/seq)
...
We can also use the scripting facilities. We create a skeleton perl
script that simply prints out the events
$ perf script -g perl
generated Perl script: perf-script.pl
We can then use this script to see the malloc() calls with a
backtrace. Prior to this patch, the backtrace was not available to
the perl scripts.
$ perf script -s perf-script.pl
probe_libc::malloc 0 1927993.748254260 14195 seq __probe_ip=140325052863264, bytes=34
[7f9ff8edd320] malloc
[7f9ff8e8eab0] set_binding_values.part.0
[7f9ff8e8eda1] __bindtextdomain
[401b22] main
[7f9ff8e82610] __libc_start_main
[402799] _start
...
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/87mvphzld0.fsf@secretsauce.net
Signed-off-by: Dima Kogan <dima@secretsauce.net>