kernel/linux.git/tools/perf/util/parse-events.c, branch v6.18.22

perf parse-events: Fix evsel allocation failure

2026-01-30T09:32:09+00:00

[ Upstream commit 1eb217ab2e737609f8a861b517649e82e7236d05 ] If evsel__new_idx() returns NULL, the function currently jumps to label 'out_err'. Here, references to `cpus` and `pmu_cpus` are dropped. Also, resources held by evsel->name and evsel->metric_id are freed. But if evsel__new_idx() returns NULL, it can lead to NULL pointer dereference. Fixes: cd63c22168257a0b ("perf parse-events: Minor __add_event refactoring") Signed-off-by: Faisal Bukhari Reviewed-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf parse-events: Make X modifier more respectful of groups

2025-12-18T13:02:32+00:00

[ Upstream commit 800201997a509c298e74696da3586d82b1a2b6f4 ] Events with an X modifier were reordered within a group, for example slots was made the leader in: ``` $ perf record -e '{cpu/mem-stores/ppu,cpu/slots/uX}' -- sleep 1 ``` Fix by making `dont_regroup` evsels always use their index for sorting. Make the cur_leader, when fixing the groups, be that of `dont_regroup` evsel so that the `dont_regroup` evsel doesn't become a leader. On a tigerlake this patch corrects this and meets expectations in: ``` $ perf stat -e '{cpu/mem-stores/,cpu/slots/uX}' -a -- sleep 0.1 Performance counter stats for 'system wide': 83,458,652 cpu/mem-stores/ 2,720,854,880 cpu/slots/uX 0.103780587 seconds time elapsed $ perf stat -e 'slots,slots:X' -a -- sleep 0.1 Performance counter stats for 'system wide': 732,042,247 slots (48.96%) 643,288,155 slots:X (51.04%) 0.102731018 seconds time elapsed ``` Closes: https://lore.kernel.org/lkml/18f20d38-070c-4e17-bc90-cf7102e1e53d@linux.intel.com/ Fixes: 035c17893082 ("perf parse-events: Add 'X' modifier to exclude an event from being regrouped") Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf parse-events: Fix legacy cache events if event is duplicated in a PMU

2025-12-18T13:02:29+00:00

[ Upstream commit b7b76f607a15f16031001687e733046b5f6f5d86 ] The term list when adding an event to a PMU is expected to have the event name for the alias lookup. Also, set found_supported so that -EINVAL isn't returned. Fixes: 62593394f66a ("perf parse-events: Legacy cache names on all PMUs and lower priority") Tested-by: Thomas Richter Signed-off-by: Ian Rogers Tested-by: James Clark Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf record: Add ratio-to-prev term

2025-10-03T19:49:51+00:00

Provide ratio-to-prev term which allows the user to set the event sample period of two events corresponding to a desired ratio. If using on an Intel x86 platform with Auto Counter Reload support, also set corresponding event's config2 attribute with a bitmask which counters to reset and which counters to sample if the desired ratio is met or exceeded. On other platforms, only the sample period is affected by the ratio-to-prev term. Reviewed-by: Ian Rogers Signed-off-by: Thomas Falcon Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Dapeng Mi Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf parse-events: Add 'X' modifier to exclude an event from being regrouped

2025-09-12T18:53:32+00:00

The function parse_events__sort_events_and_fix_groups is needed to fix uncore events like: ``` $ perf stat -e '{data_read,data_write}' ... ``` so that the multiple uncore PMUs have a group each of data_read and data_write events. The same function will perform architecture sorting and group fixing, in particular for Intel topdown/perf-metric events. Grouping multiple perf metric events together causes perf_event_open to fail as the group can only support one. This means command lines like: ``` $ perf stat -e 'slots,slots' ... ``` fail as the slots events are forced into a group together to try to satisfy the perf-metric event constraints. As the user may know better than parse_events__sort_events_and_fix_groups add a 'X' modifier to skip its regrouping behavior. This allows the following to succeed rather than fail on the second slots event being opened: ``` $ perf stat -e 'slots,slots:X' -a sleep 1 Performance counter stats for 'system wide': 6,834,154,071 cpu_core/slots/ (50.13%) 5,548,629,453 cpu_core/slots/X (49.87%) 1.002634606 seconds time elapsed ``` Closes: https://lore.kernel.org/lkml/20250822082233.1850417-1-dapeng1.mi@linux.intel.com/ Reported-by: Dapeng Mi Reported-by: Xudong Hao Reviewed-by: Dapeng Mi Signed-off-by: Ian Rogers Tested-by: Dapeng Mi Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Greg Kroah-Hartman Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Yoshihiro Furudera Signed-off-by: Arnaldo Carvalho de Melo

perf parse-events: Handle fake PMUs in CPU terms

2025-09-04T21:08:56+00:00

The "Parsing of PMU event table metrics with fake PMUs" will test metrics on machines/models that may be missing a PMU, in such a case the fake_pmu should be used to avoid errors. Metrics that get the cpumask from a different PMU, such as "tsc/cpu=cpu_atom/", also need to be resilient in this test. The parse_events_state fake_pmu is set when missing PMUs should be ignored. So that it can be queried, pass it to the config term functions, as well as to get_config_cpu, then ignore failures when fake_pmu is set. Some minor code refactoring to cut down on the indent and remove some redundant checks. Fixes: bd741d80dc65922c ("perf parse-events: Allow the cpu term to be a PMU or CPU range") Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andreas Färber Cc: Caleb Biggers Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: linux-actions@lists.infradead.org Cc: Manivannan Sadhasivam Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Weilin Wang Link: https://lore.kernel.org/r/20250818190416.145274-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tp_pmu: Factor existing tracepoint logic to new file

2025-07-26T23:31:43+00:00

Start the creation of a tracepoint PMU abstraction. Tracepoint events don't follow the regular sysfs perf conventions. Eventually the new PMU abstraction will bridge the gap so tracepoint events look more like regular perf ones. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20250725185202.68671-5-irogers@google.com Signed-off-by: Namhyung Kim

perf parse-events: Remove non-json software events

2025-07-26T23:31:43+00:00

Remove the hard coded encodings from parse-events. This has the consequence that software events are matched using the sysfs/json priority, will be case insensitive and will be wildcarded across PMUs. As there were software and hardware types in the parsing code, the removal means software vs hardware logic can be removed and hardware assumed. Now the perf json provides detailed descriptions of software events, remove the previous listing support that didn't contain event descriptions. When globbing is required for the "sw" option in perf list, use string PMU globbing as was done previously for the tool PMU. The output of `perf list sw` command changed like this. Before: List of pre-defined events (to be used in -e or -M): alignment-faults [Software event] bpf-output [Software event] cgroup-switches [Software event] context-switches OR cs [Software event] cpu-clock [Software event] cpu-migrations OR migrations [Software event] dummy [Software event] emulation-faults [Software event] major-faults [Software event] minor-faults [Software event] page-faults OR faults [Software event] task-clock [Software event] After: List of pre-defined events (to be used in -e or -M): software: alignment-faults [Number of kernel handled memory alignment faults. Unit: software] bpf-output [An event used by BPF programs to write to the perf ring buffer. Unit: software] cgroup-switches [Number of context switches to a task in a different cgroup. Unit: software] context-switches [Number of context switches [This event is an alias of cs]. Unit: software] cpu-clock [Per-CPU high-resolution timer based event. Unit: software] cpu-migrations [Number of times a process has migrated to a new CPU [This event is an alias of migrations]. Unit: software] cs [Number of context switches [This event is an alias of context-switches]. Unit: software] dummy [A placeholder event that doesn't count anything. Unit: software] ... Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20250725185202.68671-4-irogers@google.com Signed-off-by: Namhyung Kim

perf parse-events: Fix missing slots for Intel topdown metric events

2025-07-24T20:41:35+00:00

Topdown metric events require grouping with a slots event. In perf metrics this is currently achieved by metrics adding an unnecessary "0 * tma_info_thread_slots". New TMA metrics trigger optimizations of the metric expression that removes the event and breaks the metric due to the missing but required event. Add a pass immediately before sorting and fixing parsed events, that insert a slots event if one is missing. Update test expectations to match this. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250719030517.1990983-15-irogers@google.com Signed-off-by: Namhyung Kim

perf parse-events: Support user CPUs mixed with threads/processes

2025-07-24T20:41:35+00:00

Counting events system-wide with a specified CPU prior to this change worked: ``` $ perf stat -e 'msr/tsc/,msr/tsc,cpu=cpu_core/,msr/tsc,cpu=cpu_atom/' -a sleep 1 Performance counter stats for 'system wide': 59,393,419,099 msr/tsc/ 33,927,965,927 msr/tsc,cpu=cpu_core/ 25,465,608,044 msr/tsc,cpu=cpu_atom/ ``` However, when counting with process the counts became system wide: ``` $ perf stat -e 'msr/tsc/,msr/tsc,cpu=cpu_core/,msr/tsc,cpu=cpu_atom/' perf test -F 10 10.1: Basic parsing test : Ok 10.2: Parsing without PMU name : Ok 10.3: Parsing with PMU name : Ok Performance counter stats for 'perf test -F 10': 59,233,549 msr/tsc/ 59,227,556 msr/tsc,cpu=cpu_core/ 59,224,053 msr/tsc,cpu=cpu_atom/ ``` Make the handling of CPU maps with event parsing clearer. When an event is parsed creating an evsel the cpus should be either the PMU's cpumask or user specified CPUs. Update perf_evlist__propagate_maps so that it doesn't clobber the user specified CPUs. Try to make the behavior clearer, firstly fix up missing cpumasks. Next, perform sanity checks and adjustments from the global evlist CPU requests and for the PMU including simplifying to the "any CPU"(-1) value. Finally remove the event if the cpumask is empty. So that events are opened with a CPU and a thread change stat's create_perf_stat_counter to give both. With the change things are fixed: ``` $ perf stat --no-scale -e 'msr/tsc/,msr/tsc,cpu=cpu_core/,msr/tsc,cpu=cpu_atom/' perf test -F 10 10.1: Basic parsing test : Ok 10.2: Parsing without PMU name : Ok 10.3: Parsing with PMU name : Ok Performance counter stats for 'perf test -F 10': 63,704,975 msr/tsc/ 47,060,704 msr/tsc,cpu=cpu_core/ (4.62%) 16,640,591 msr/tsc,cpu=cpu_atom/ (2.18%) ``` However, note the "--no-scale" option is used. This is necessary as the running time for the event on the counter isn't the same as the enabled time because the thread doesn't necessarily run on the CPUs specified for the counter. All counter values are scaled with: scaled_value = value * time_enabled / time_running and so without --no-scale the scaled_value becomes very large. This problem already exists on hybrid systems for the same reason. Here are 2 runs of the same code with an instructions event that counts the same on both types of core, there is no real multiplexing happening on the event: ``` $ perf stat -e instructions perf test -F 10 ... Performance counter stats for 'perf test -F 10': 87,896,447 cpu_atom/instructions/ (14.37%) 98,171,964 cpu_core/instructions/ (85.63%) ... $ perf stat --no-scale -e instructions perf test -F 10 ... Performance counter stats for 'perf test -F 10': 13,069,890 cpu_atom/instructions/ (19.32%) 83,460,274 cpu_core/instructions/ (80.68%) ... ``` The scaling has inflated per-PMU instruction counts and the overall count by 2x. To fix this the kernel needs changing when a task+CPU event (or just task event on hybrid) is scheduled out. A fix could be that the state isn't inactive but off for such events, so that time_enabled counts don't accumulate on them. Reviewed-by: Thomas Falcon Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250719030517.1990983-13-irogers@google.com Signed-off-by: Namhyung Kim