The index into the cpumap array and the number of entries within the
array can never be negative, so let's make them unsigned. This is
prompted by reports that gcc 13 with -O6 is giving a
alloc-size-larger-than errors. The change makes the cpumap changes and
then updates the declaration of index variables throughout perf and
libperf to be unsigned. The two things are hard to separate as
compiler warnings about mixing signed and unsigned types breaks the
build.
Reported-by: Chingbin Li <liqb365@163.com>
Closes: https://lore.kernel.org/lkml/20260212025127.841090-1-liqb365@163.com/
Tested-by: Chingbin Li <liqb365@163.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Currently, `perf stat` skips or hides metrics when the underlying
hardware events cannot be counted (e.g., due to insufficient permissions
or unsupported events).
In `--metric-only` mode, this often results in missing columns or blank
spaces, making the output difficult to parse.
Modify the logic to ensure metrics are consistently displayed by
propagating NAN (Not a Number) through the expression evaluator.
Specifically:
1. Update `prepare_metric()` in stat-shadow.c to treat uncounted events
(where `run == 0`) as NAN. This leverages the existing math in expr.y
to propagate NAN through metric expressions.
2. Remove the early return in the display logic's `printout()` function
that was previously skipping metrics in `--metric-only` mode for
failed events.
l
3. Simplify `perf_stat__skip_metric_event()` to no longer depend on
event runtime.
Tested:
1. `perf all metrics test` did not crash while paranoid is 2.
2. Multiple combinations with `CPUs_utilized` while paranoid is 2.
$ ./perf stat -M CPUs_utilized -a -- sleep 1
Performance counter stats for 'system wide':
<not supported> msec cpu-clock:u # nan CPUs CPUs_utilized
1,006,356,120 duration_time
1.004375550 seconds time elapsed
$ ./perf stat -M CPUs_utilized -a -j -- sleep 1
{"counter-value" : "<not supported>", "unit" : "msec", "event" : "cpu-clock:u", "event-runtime" : 0, "pcnt-running" : 100.00, "metric-value" : "nan", "metric-unit" : "CPUs CPUs_utilized"}
{"counter-value" : "1006642462.000000", "unit" : "", "event" : "duration_time", "event-runtime" : 1, "pcnt-running" : 100.00}
$ ./perf stat -M CPUs_utilized -a --metric-only -- sleep 1
Performance counter stats for 'system wide':
CPUs CPUs_utilized
nan
1.004424652 seconds time elapsed
$ ./perf stat -M CPUs_utilized -a --metric-only -j -- sleep 1
{"CPUs CPUs_utilized" : "none"}
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
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: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit bc22de9bcd ("perf stat: Display time in precision based on
std deviation") added multirun workload elapsed time. There was an
effort to make the precision in the output most useful for the user,
however, when gathering over runs it means the formatting varies. This
change just makes the output format fixed.
Before:
```
$ while :; do perf stat --null --repeat 3 sleep 0.1 2>&1 | grep elapsed; done
0.101140 +- 0.000149 seconds time elapsed ( +- 0.15% )
0.1011396 +- 0.0000218 seconds time elapsed ( +- 0.02% )
0.101331 +- 0.000124 seconds time elapsed ( +- 0.12% )
^C
$ while :; do perf stat --null --repeat 3 sleep 1 2>&1 | grep elapsed; done
1.001317 +- 0.000146 seconds time elapsed ( +- 0.01% )
1.001377 +- 0.000172 seconds time elapsed ( +- 0.02% )
1.00253 +- 0.00131 seconds time elapsed ( +- 0.13% )
```
After:
```
$ while :; do perf stat --null --repeat 3 sleep 0.1 2>&1 | grep elapsed; done
0.101406408 +- 0.000064778 seconds time elapsed ( +- 0.06% )
0.101367315 +- 0.000027253 seconds time elapsed ( +- 0.03% )
0.101434164 +- 0.000084750 seconds time elapsed ( +- 0.08% )
^C
$ while :; do perf stat --null --repeat 3 sleep 1 2>&1 | grep elapsed; done
1.001525467 +- 0.000051703 seconds time elapsed ( +- 0.01% )
1.001375093 +- 0.000116200 seconds time elapsed ( +- 0.01% )
1.001141025 +- 0.000046361 seconds time elapsed ( +- 0.00% )
```
Closes: https://lore.kernel.org/lkml/aTQRgAOpKyI53TEq@gmail.com/
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Chun-Tse Shao <ctshao@google.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
0 counters may occur in hypervisor settings but metric-only output is
always expected. This resolves an issue in the "perf stat STD output
linter" test.
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Thomas Falcon <thomas.falcon@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
One of my concern in the perf stat output was the alignment in the
metrics and shadow stats. I think it missed to calculate the basic
output length using COUNTS_LEN and EVNAME_LEN but missed to add the
unit length like "msec" and surround 2 spaces. I'm not sure why it's
not printed below though.
But anyway, now it shows correctly aligned metric output.
$ perf stat true
Performance counter stats for 'true':
859,772 task-clock # 0.395 CPUs utilized
0 context-switches # 0.000 /sec
0 cpu-migrations # 0.000 /sec
56 page-faults # 65.134 K/sec
1,075,022 instructions # 0.86 insn per cycle
1,255,911 cycles # 1.461 GHz
220,573 branches # 256.548 M/sec
7,381 branch-misses # 3.35% of all branches
TopdownL1 # 19.2 % tma_retiring
# 28.6 % tma_backend_bound
# 9.5 % tma_bad_speculation
# 42.6 % tma_frontend_bound
0.002174871 seconds time elapsed ^
|
0.002154000 seconds user |
0.000000000 seconds sys here
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Remove code that tested the "unit" as in KB/sec for certain hard coded
metric values and did workarounds.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Now that the metrics are encoded in common json the hard coded
printing means the metrics are shown twice. Remove the hard coded
version.
This means that when specifying events, and those events correspond to
a hard coded metric, the metric will no longer be displayed. The
metric will be displayed if the metric is requested. Due to the adhoc
printing in the previous approach it was often found frustrating, the
new approach avoids this.
The default perf stat output on an alderlake now looks like:
```
$ perf stat -a -- sleep 1
Performance counter stats for 'system wide':
19,697 context-switches # nan cs/sec cs_per_second
TopdownL1 (cpu_core) # 10.7 % tma_bad_speculation
# 24.9 % tma_frontend_bound
TopdownL1 (cpu_core) # 34.3 % tma_backend_bound
# 30.1 % tma_retiring
6,593 page-faults # nan faults/sec page_faults_per_second
729,065,658 cpu_atom/cpu-cycles/ # nan GHz cycles_frequency (49.79%)
1,605,131,101 cpu_core/cpu-cycles/ # nan GHz cycles_frequency
# 19.7 % tma_bad_speculation
# 14.2 % tma_retiring (50.14%)
# 37.3 % tma_frontend_bound (50.31%)
87,302,268 cpu_atom/branches/ # nan M/sec branch_frequency (60.27%)
512,046,956 cpu_core/branches/ # nan M/sec branch_frequency
1,111 cpu-migrations # nan migrations/sec migrations_per_second
# 28.8 % tma_backend_bound (60.26%)
0.00 msec cpu-clock # 0.0 CPUs CPUs_utilized
392,509,323 cpu_atom/instructions/ # 0.6 instructions insn_per_cycle (60.19%)
2,990,369,310 cpu_core/instructions/ # 1.9 instructions insn_per_cycle
3,493,478 cpu_atom/branch-misses/ # 5.9 % branch_miss_rate (49.69%)
7,297,531 cpu_core/branch-misses/ # 1.4 % branch_miss_rate
1.006621701 seconds time elapsed
```
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Some Default group metrics require their events showing for
consistency with perf's previous behavior. Add a flag to indicate when
this is the case and use it in stat-display.
As events are coming from Default metrics remove that default hardware
and software events from perf stat.
Following this change the default perf stat output on an alderlake looks like:
```
$ perf stat -a -- sleep 1
Performance counter stats for 'system wide':
20,550 context-switches # nan cs/sec cs_per_second
TopdownL1 (cpu_core) # 9.0 % tma_bad_speculation
# 28.1 % tma_frontend_bound
TopdownL1 (cpu_core) # 29.2 % tma_backend_bound
# 33.7 % tma_retiring
6,685 page-faults # nan faults/sec page_faults_per_second
790,091,064 cpu_atom/cpu-cycles/
# nan GHz cycles_frequency (49.83%)
2,563,918,366 cpu_core/cpu-cycles/
# nan GHz cycles_frequency
# 12.3 % tma_bad_speculation
# 14.5 % tma_retiring (50.20%)
# 33.8 % tma_frontend_bound (50.24%)
76,390,322 cpu_atom/branches/ # nan M/sec branch_frequency (60.20%)
1,015,173,047 cpu_core/branches/ # nan M/sec branch_frequency
1,325 cpu-migrations # nan migrations/sec migrations_per_second
# 39.3 % tma_backend_bound (60.17%)
0.00 msec cpu-clock # 0.000 CPUs utilized
# 0.0 CPUs CPUs_utilized
554,347,072 cpu_atom/instructions/ # 0.64 insn per cycle
# 0.6 instructions insn_per_cycle (60.14%)
5,228,931,991 cpu_core/instructions/ # 2.04 insn per cycle
# 2.0 instructions insn_per_cycle
4,308,874 cpu_atom/branch-misses/ # 5.65% of all branches
# 5.6 % branch_miss_rate (49.76%)
9,890,606 cpu_core/branch-misses/ # 0.97% of all branches
# 1.0 % branch_miss_rate
1.005477803 seconds time elapsed
```
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The rblist of metric_event that then have a list of associated
metric_expr is moved out of the stat_config and into the evlist. This
is done as part of refactoring things for python, having the state
split in two places complicates that implementation. The evlist is
doing the harder work of enabling and disabling events, the metrics
are needed to compute a value and it doesn't seem unreasonable to hang
them from the evlist.
Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250710235126.1086011-7-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Prior to this patch evlist__has_hybrid would return false if the
processor wasn't hybrid or the evlist didn't contain any core
events. If the only PMU used by events was cpu_core then it would
true even though there are no cpu_atom events. For example:
```
$ perf stat --cputype=cpu_core -e '{cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles,cycles}' true
Performance counter stats for 'true':
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
<not counted> cpu_core/cycles/ (0.00%)
0.001981900 seconds time elapsed
0.002311000 seconds user
0.000000000 seconds sys
```
This patch changes evlist__has_hybrid to return true only if the
evlist contains events from >1 core PMU. This means the NMI watchdog
warning is shown for the case above.
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Levi Yun <yeoreum.yun@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20250402201549.4090305-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Legacy hybrid events have attr.type == PERF_TYPE_HARDWARE, so they look
like plain legacy events if we only look at attr.type. But legacy events
should still be uniquified if they were opened on a non-legacy PMU. Fix
it by checking if the evsel is hybrid and forcing needs_uniquify
before looking at the attr.type.
This restores PMU names on hybrid systems and also changes "perf stat
metrics (shadow stat) test" from a FAIL back to a SKIP (on hybrid). The
test was gated on "cycles" appearing alone which doesn't happen on
here.
Before:
$ perf stat -- true
...
<not counted> instructions:u (0.00%)
162,536 instructions:u # 0.58 insn per cycle
...
After:
$ perf stat -- true
...
<not counted> cpu_atom/instructions/u (0.00%)
162,541 cpu_core/instructions/u # 0.62 insn per cycle
...
Fixes: 357b965deb ("perf stat: Changes to event name uniquification")
Suggested-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20250226145526.632380-1-james.clark@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The existing logic would disable uniquification on an evlist or enable
it per evsel, this is unfortunate as uniquification is most needed
when events have the same name and so the whole evlist must be
considered. Change the initial disable uniquify on an evlist
processing to also set a needs_uniquify flag, for cases like the
matching event names. This must be done as an initial pass as
uniquification of an event name will change the behavior of the
check. Keep the per counter uniquification but now only uniquify event
names when the needs_uniquify flag is set.
Before this change a hwmon like temp1 wouldn't be uniquified and
afterwards it will (ie the PMU is added to the temp1 event's name).
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20250201074320.746259-6-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
We decided to hide NULL metric-units rather than showing it as "(null)"
when a dependent event for a metric doesn't exist. But on hybrid systems
if the process doesn't hit a PMU you get an empty string metric unit
instead. To make it consistent change all empty strings to NULL.
Note that metric-threshold is already hidden in this case without this
change.
Where a process only runs on cpu_core and never hits cpu_atom:
Before:
$ perf stat -j -- true
...
{"counter-value" : "<not counted>", "unit" : "", "event" : "cpu_atom/branch-misses/", "event-runtime" : 0, "pcnt-running" : 0.00, "metric-value" : "0.000000", "metric-unit" : ""}
{"counter-value" : "6326.000000", "unit" : "", "event" : "cpu_core/branch-misses/", "event-runtime" : 293786, "pcnt-running" : 100.00, "metric-value" : "3.553394", "metric-unit" : "of all branches", "metric-threshold" : "good"}
...
After:
...
{"counter-value" : "<not counted>", "unit" : "", "event" : "cpu_atom/branch-misses/", "event-runtime" : 0, "pcnt-running" : 0.00}
{"counter-value" : "5778.000000", "unit" : "", "event" : "cpu_core/branch-misses/", "event-runtime" : 282240, "pcnt-running" : 100.00, "metric-value" : "3.226797", "metric-unit" : "of all branches", "metric-threshold" : "good"}
...
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20241112160048.951213-3-james.clark@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now that printing metric-value and metric-unit is optional,
print_running_json() shouldn't add the comma in case it becomes
trailing.
Replace all manual JSON comma stuff with a json_out() function that uses
the existing os->first tracking and auto inserts a comma if it's needed.
Update the test to handle that two of the fields can be missing.
This fixes the following test failure on Cortex A57 where the branch
misses metric is missing a required event:
$ perf test -vvv "json output"
106: perf stat JSON output linter:
--- start ---
test child forked, pid 665682
Checking json output: no args Test failed for input:
{"counter-value" : "3112.000000", "unit" : "",
"event" : "armv8_pmuv3_1/branch-misses/",
"event-runtime" : 20699340, "pcnt-running" : 100.00, }
...
json.decoder.JSONDecodeError: Expecting property name enclosed in
double quotes: line 12 column 144 (char 2109)
---- end(-1) ----
106: perf stat JSON output linter : FAILED!
Fixes: e1cc918b6c ("perf stat: Drop metric-unit if unit is NULL")
Signed-off-by: James Clark <james.clark@linaro.org>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
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: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20241112160048.951213-2-james.clark@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>