kernel/tools/perf/Documentation/perf-stat.txt, branch linux-4.17.y

perf stat: Enable 1ms interval for printing event counters values

2018-04-12T12:29:31Z

Currently print count interval for performance counters values is limited by 10ms so reading the values at frequencies higher than 100Hz is restricted by the tool. This change makes perf stat -I possible on frequencies up to 1KHz and, to some extent, makes perf stat -I to be on-par with perf record sampling profiling. When running perf stat -I for monitoring e.g. PCIe uncore counters and at the same time profiling some I/O workload by perf record e.g. for cpu-cycles and context switches, it is then possible to observe consolidated CPU/OS/IO(Uncore) performance picture for that workload. Tool overhead warning printed when specifying -v option can be missed due to screen scrolling in case you have output to the console so message is moved into help available by running perf stat -h. Signed-off-by: Alexey Budankov Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/b842ad6a-d606-32e4-afe5-974071b5198e@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf pmu: Auto-merge PMU events created by prefix or glob match

2018-03-08T13:05:49Z

Auto-merge for these events was disabled when auto-merging of non-alias events was disabled in commit 63ce844 (perf stat: Only auto-merge events that are PMU aliases). Non-merging of legacy events is preserved: $ perf stat -ag -e cache-misses,cache-misses sleep 1 Performance counter stats for 'system wide': 86,323 cache-misses 86,323 cache-misses 1.002623307 seconds time elapsed But prefix or glob matching auto-merges the events created: $ perf stat -a -e l3cache/read-miss/ sleep 1 Performance counter stats for 'system wide': 328 l3cache/read-miss/ 1.002627008 seconds time elapsed $ perf stat -a -e l3cache_0_[01]/read-miss/ sleep 1 Performance counter stats for 'system wide': 172 l3cache/read-miss/ 1.002627008 seconds time elapsed As with events created with aliases, auto-merging can be suppressed with the --no-merge option: $ perf stat -a -e l3cache/read-miss/ --no-merge sleep 1 Performance counter stats for 'system wide': 67 l3cache/read-miss/ 67 l3cache/read-miss/ 63 l3cache/read-miss/ 60 l3cache/read-miss/ 1.002622192 seconds time elapsed Signed-off-by: Agustin Vega-Frias Acked-by: Andi Kleen Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Timur Tabi Cc: linux-arm-kernel@lists.infradead.org Change-Id: I0a47eed54c05e1982ca964d743b37f50f60c508c Link: http://lkml.kernel.org/r/1520345084-42646-4-git-send-email-agustinv@codeaurora.org Signed-off-by: Arnaldo Carvalho de Melo

perf pmu: Support wildcards on pmu name in dynamic pmu events

2018-03-08T13:05:25Z

Starting on v4.12 event parsing code for dynamic pmu events already supports prefix-based matching of multiple pmus when creating dynamic events. E.g., in a system with the following dynamic pmus: mypmu_0 mypmu_1 mypmu_2 mypmu_4 passing mypmu// as an event spec will result in the creation of the event in all of the pmus. This change expands this matching through the use of fnmatch so glob-like expressions can be used to create events in multiple pmus. E.g., in the system described above if a user only wants to create the event in mypmu_0 and mypmu_1, mypmu_[01]// can be passed. Signed-off-by: Agustin Vega-Frias Acked-by: Andi Kleen Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: linux-arm-kernel@lists.infradead.org Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Timur Tabi Change-Id: Icb25653fc5d5239c20f3bffdfdf4ab4c9c9bb20b Link: http://lkml.kernel.org/r/1520454947-16977-1-git-send-email-agustinv@codeaurora.org Signed-off-by: Arnaldo Carvalho de Melo

perf cgroup: Simplify arguments when tracking multiple events

2018-02-22T13:02:27Z

When using -G with one cgroup and -e with multiple events, only the first event gets the correct cgroup setting, all events from the second onwards will track system-wide events. If the user wants to track multiple events for a specific cgroup, the user must give parameters like the following: $ perf stat -e e1 -e e2 -e e3 -G test,test,test This patch simplify this case, just type one cgroup: $ perf stat -e e1 -e e2 -e e3 -G test $ mkdir -p /sys/fs/cgroup/perf_event/empty_cgroup $ perf stat -e cycles -e cache-misses -a -I 1000 -G empty_cgroup Before: 1.001007226 cycles empty_cgroup 1.001007226 7,506 cache-misses After: 1.000834097 cycles empty_cgroup 1.000834097 cache-misses empty_cgroup Signed-off-by: weiping zhang Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180129154805.GA6284@localhost.didichuxing.com [ Improved the doc text a bit, providing an example for cgroup + system wide counting ] Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add support to print counts after a period of time

2018-02-16T13:18:06Z

Introduce a new option to print counts after N milliseconds and update 'perf stat' documentation accordingly. Show below is the output of the new option for perf stat. $ perf stat --time 2000 -e cycles -a Performance counter stats for 'system wide': 157,260,423 cycles 2.003060766 seconds time elapsed We can print the count deltas after N milliseconds with this new introduced option. This option is not supported with "-I" option. In addition, according to Kangliang's patch(19afd10410957), the monitoring overhead for system-wide core event could be very high if the interval-print parameter was below 100ms, and the limitation value is 10ms. So the same warning will be displayed when the time is set between 10ms to 100ms, and the minimal time is limited to 10ms. Users can make a decision according to their spcific cases. Committer notes: This actually stops the workload after the specified time, then prints the counts. So I renamed the option to --timeout and updated the documentation to state that it will not just print the counts after the specified time, but will really stop the 'perf stat' session and print the counts. The rename from 'time' to 'timeout' also fixes the build in systems where 'time' is used by glibc and can't be used as a name of a variable, such as centos:5 and centos:6. Changes since v3: - none. Changes since v2: - modify the time check in __run_perf_stat func to keep some consistency with the workload case. - add the warning when the time is set between 10ms to 100ms. - add the pr_err when the time is set below 10ms. Changes since v1: - none. Signed-off-by: yuzhoujian Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: David Ahern Cc: Kan Liang Cc: Milian Wolff Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1517217923-8302-3-git-send-email-ufo19890607@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add support to print counts for fixed times

2018-02-16T13:09:24Z

Introduce a new option to print counts for fixed number of times and update 'perf stat' documentation accordingly. Show below is the output of the new option for perf stat. $ perf stat -I 1000 --interval-count 2 -e cycles -a # time counts unit events 1.002827089 93,884,870 cycles 2.004231506 56,573,446 cycles We can just print the counts for several times with this newly introduced option. The usage of it is a little like 'vmstat', and it should be used together with "-I" option. $ vmstat -n 1 2 procs ---------memory-------------- --swap- ----io-- -system-- ------cpu--- r b swpd free buff cache si so bi bo in cs us sy id wa st 0 0 0 78270544 547484 51732076 0 0 0 20 1 1 1 0 99 0 0 0 0 0 78270512 547484 51732080 0 0 0 16 477 1555 0 0 100 0 0 Changes since v3: - merge interval_count check and times check to one line. - fix the wrong indent in stat.h - use stat_config.times instead of 'times' in cmd_stat function. Changes since v2: - none. Changes since v1: - change the name of the new option "times-print" to "interval-count". - keep the new option interval specifically. Signed-off-by: yuzhoujian Acked-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: David Ahern Cc: Kan Liang Cc: Milian Wolff Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Wang Nan Link: http://lkml.kernel.org/r/1517217923-8302-2-git-send-email-ufo19890607@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Support JSON metrics in perf stat

2017-09-13T12:49:13Z

Add generic support for standalone metrics specified in JSON files to perf stat. A metric is a formula that uses multiple events to compute a higher level result (e.g. IPC). Previously metrics were always tied to an event and automatically enabled with that event. But now change it that we can have standalone metrics. They are in the same JSON data structure as events, but don't have an event name. We also allow to organize the metrics in metric groups, which allows a short cut to select several related metrics at once. Add a new -M / --metrics option to perf stat that adds the metrics or metric groups specified. Add the core code to manage and parse the metric groups. They are collected from the JSON data structures into a separate rblist. When computing shadow values look for metrics in that list. Then they are computed using the existing saved values infrastructure in stat-shadow.c The actual JSON metrics are in a separate pull request. % perf stat -M Summary --metric-only -a sleep 1 Performance counter stats for 'system wide': Instructions CLKS CPU_Utilization GFLOPs SMT_2T_Utilization Kernel_Utilization 317614222.0 1392930775.0 0.0 0.0 0.2 0.1 1.001497549 seconds time elapsed % perf stat -M GFLOPs flops Performance counter stats for 'flops': 3,999,541,471 fp_comp_ops_exe.sse_scalar_single # 1.2 GFLOPs (66.65%) 14 fp_comp_ops_exe.sse_scalar_double (66.65%) 0 fp_comp_ops_exe.sse_packed_double (66.67%) 0 fp_comp_ops_exe.sse_packed_single (66.70%) 0 simd_fp_256.packed_double (66.70%) 0 simd_fp_256.packed_single (66.67%) 0 duration_time 3.238372845 seconds time elapsed v2: Add missing header file v3: Move find_map to pmu.c Signed-off-by: Andi Kleen Acked-by: Jiri Olsa Link: http://lkml.kernel.org/r/20170831194036.30146-7-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Fix path to PMU formats in documentation

2017-08-28T14:05:09Z

As defined in tools/perf/util/pmu.c, the EVENT_SOURCE_DEVICE_PATH is /sys/bus/event_source/devices/ (no traling 's' in event_source) This patch corrects the path in the perf stat documentation Signed-off-by: Jack Henschel Cc: Alexander Shishkin Cc: Jack Henschel Cc: Peter Zijlstra Cc: trivial@kernel.org Link: http://lkml.kernel.org/r/20170824132022.10934-1-jackdev@mailbox.org Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Add support to measure SMI cost

2017-06-21T14:35:35Z

Implementing a new --smi-cost mode in perf stat to measure SMI cost. During the measurement, the /sys/device/cpu/freeze_on_smi will be set. The measurement can be done with one counter (unhalted core cycles), and two free running MSR counters (IA32_APERF and SMI_COUNT). In practice, the percentages of SMI core cycles should be more useful than absolute value. So the output will be the percentage of SMI core cycles and SMI#. metric_only will be set by default. SMI cycles% = (aperf - unhalted core cycles) / aperf Here is an example output. Performance counter stats for 'sudo echo ': SMI cycles% SMI# 0.1% 1 0.010858678 seconds time elapsed Users who wants to get the actual value can apply additional --no-metric-only. Signed-off-by: Kan Liang Acked-by: Jiri Olsa Cc: Andi Kleen Cc: Kan Liang Cc: Peter Zijlstra Cc: Robert Elliott Cc: Stephane Eranian Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1495825538-5230-3-git-send-email-kan.liang@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf stat: Collapse identically named events

2017-03-21T19:04:11Z

The uncore PMU has a lot of duplicated PMUs for different subsystems. When expanding an uncore alias we usually end up with a large number of identically named aliases, which makes perf stat output difficult to read. Automatically sum them up in perf stat, unless --no-merge is specified. This can be default because only the uncores generally have duplicated aliases. Other PMUs have unique names. Before: % perf stat --no-merge -a -e unc_c_llc_lookup.any sleep 1 Performance counter stats for 'system wide': 694,976 Bytes unc_c_llc_lookup.any 706,304 Bytes unc_c_llc_lookup.any 956,608 Bytes unc_c_llc_lookup.any 782,720 Bytes unc_c_llc_lookup.any 605,696 Bytes unc_c_llc_lookup.any 442,816 Bytes unc_c_llc_lookup.any 659,328 Bytes unc_c_llc_lookup.any 509,312 Bytes unc_c_llc_lookup.any 263,936 Bytes unc_c_llc_lookup.any 592,448 Bytes unc_c_llc_lookup.any 672,448 Bytes unc_c_llc_lookup.any 608,640 Bytes unc_c_llc_lookup.any 641,024 Bytes unc_c_llc_lookup.any 856,896 Bytes unc_c_llc_lookup.any 808,832 Bytes unc_c_llc_lookup.any 684,864 Bytes unc_c_llc_lookup.any 710,464 Bytes unc_c_llc_lookup.any 538,304 Bytes unc_c_llc_lookup.any 1.002577660 seconds time elapsed After: % perf stat -a -e unc_c_llc_lookup.any sleep 1 Performance counter stats for 'system wide': 2,685,120 Bytes unc_c_llc_lookup.any 1.002648032 seconds time elapsed v2: Split collect_aliases. Rename alias flag. v3: Make sure unsupported/not counted is always printed. v4: Factor out callback change into separate patch. v5: Move check for bad results here Move merged check into collect_data Signed-off-by: Andi Kleen Acked-by: Jiri Olsa Link: http://lkml.kernel.org/r/20170320201711.14142-3-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo