kernel/linux.git/tools/perf/util/expr.c, branch v7.1-rc5

perf expr: Add '\n' in literal parse errors

2026-04-03T01:10:59+00:00

Add a trailing newline for logs. Before: perf stat -C 5 Failure to read '#slots'Cannot find metric or group `Default' After: perf stat -C 5 Failure to read '#slots' Cannot find metric or group `Default' Signed-off-by: Leo Yan Reviewed-by: Ian Rogers Signed-off-by: Namhyung Kim

perf expr: Return -EINVAL for syntax error in expr__find_ids()

2026-04-03T01:10:59+00:00

expr__find_ids() propagates the parser return value directly. For syntax errors, the parser can return a positive value, but callers treat it as success, e.g., for below case on Arm64 platform: metric expr 100 * (STALL_SLOT_BACKEND / (CPU_CYCLES * #slots) - BR_MIS_PRED * 3 / CPU_CYCLES) for backend_bound parsing metric: 100 * (STALL_SLOT_BACKEND / (CPU_CYCLES * #slots) - BR_MIS_PRED * 3 / CPU_CYCLES) Failure to read '#slots' literal: #slots = nan syntax error Convert positive parser returns in expr__find_ids() to -EINVAL, as a result, the error value will be respected by callers. Before: perf stat -C 5 Failure to read '#slots'Failure to read '#slots'Failure to read '#slots'Failure to read '#slots'Segmentation fault After: perf stat -C 5 Failure to read '#slots'Cannot find metric or group `Default' Fixes: ded80bda8bc9 ("perf expr: Migrate expr ids table to a hashmap") Signed-off-by: Leo Yan Reviewed-by: Ian Rogers Signed-off-by: Namhyung Kim

perf tool_pmu: Make core_wide and target_cpu json events

2025-11-12T00:48:36+00:00

For the sake of better documentation, add core_wide and target_cpu to the tool.json. When the values of system_wide and user_requested_cpu_list are unknown, use the values from the global stat_config. Example output showing how '-a' modifies the values in `perf stat`: ``` $ perf stat -e core_wide,target_cpu true Performance counter stats for 'true': 0 core_wide 0 target_cpu 0.000993787 seconds time elapsed 0.001128000 seconds user 0.000000000 seconds sys $ perf stat -e core_wide,target_cpu -a true Performance counter stats for 'system wide': 1 core_wide 1 target_cpu 0.002271723 seconds time elapsed $ perf list ... tool: core_wide [1 if not SMT,if SMT are events being gathered on all SMT threads 1 otherwise 0. Unit: tool] ... target_cpu [1 if CPUs being analyzed,0 if threads/processes. Unit: tool] ... ``` Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf expr: Add #target_cpu literal

2025-11-12T00:48:34+00:00

For CPU nanoseconds a lot of the stat-shadow metrics use either task-clock or cpu-clock, the latter being used when target__has_cpu. Add a #target_cpu literal so that json metrics can perform the same test. Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf tool_pmu: Allow num_cpus(_online) to be specific to a cpumask

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

For hybrid metrics it is useful to know the number of p-core or e-core CPUs. If a cpumask is specified for the num_cpus or num_cpus_online tool events, compute the value relative to the given mask rather than for the full system. ``` $ sudo /tmp/perf/perf stat -e 'tool/num_cpus/,tool/num_cpus,cpu=cpu_core/, tool/num_cpus,cpu=cpu_atom/,tool/num_cpus_online/,tool/num_cpus_online, cpu=cpu_core/,tool/num_cpus_online,cpu=cpu_atom/' true Performance counter stats for 'true': 28 tool/num_cpus/ 16 tool/num_cpus,cpu=cpu_core/ 12 tool/num_cpus,cpu=cpu_atom/ 28 tool/num_cpus_online/ 16 tool/num_cpus_online,cpu=cpu_core/ 12 tool/num_cpus_online,cpu=cpu_atom/ 0.000767205 seconds time elapsed 0.000938000 seconds user 0.000000000 seconds sys ``` Reviewed-by: Thomas Falcon Signed-off-by: Ian Rogers Tested-by: James Clark Link: https://lore.kernel.org/r/20250719030517.1990983-6-irogers@google.com Signed-off-by: Namhyung Kim

perf expr: Accumulate rather than replace in the context counts

2025-07-11T19:36:40+00:00

Metrics will fill in the context to have mappings from an event to a count. When counts are added they replace existing mappings which generally shouldn't exist with aggregation. Switch to accumulating to better support cases where perf stat's aggregation isn't used and we may see a counter more than once. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250710235126.1086011-8-irogers@google.com Signed-off-by: Namhyung Kim

perf tools: Add skip check in tool_pmu__event_to_str()

2025-02-10T19:46:30+00:00

Some topdown related metrics may fail on hybrid machines. $ perf stat -M tma_frontend_bound Cannot resolve IDs for tma_frontend_bound: cpu_atom@TOPDOWN_FE_BOUND.ALL@ / (8 * cpu_atom@CPU_CLK_UNHALTED.CORE@) In the find_tool_events(), the tool_pmu__event_to_str() is used to compare the tool_events. It only checks the event name, no PMU or arch. So the tool_events[TOOL_PMU__EVENT_SLOTS] is set to true, because the p-core Topdown metrics has "slots" event. The tool_events is shared. So when parsing the e-core metrics, the "slots" is automatically added. The "slots" event as a tool event should only be available on arm64. It has a different meaning on X86. The tool_pmu__skip_event() intends handle the case. Apply it for tool_pmu__event_to_str() as well. There is a lack of sanity check in the expr__get_id(). Add the check. Closes: https://lore.kernel.org/lkml/608077bc-4139-4a97-8dc4-7997177d95c4@linux.intel.com/ Fixes: 069057239a67 ("perf tool_pmu: Move expr literals to tool_pmu") Signed-off-by: Kan Liang Reviewed-by: Ian Rogers Cc: thomas.falcon@intel.com Link: https://lore.kernel.org/r/20250207152844.302167-1-kan.liang@linux.intel.com Signed-off-by: Namhyung Kim

perf expr: Initialize is_test value in expr__ctx_new()

2024-12-12T19:12:37+00:00

When expr_parse_ctx is allocated by expr_ctx_new(), expr_scanner_ctx->is_test isn't initialize, so it has garbage value. this can affects the result of expr__parse() return when it parses non-exist event literal according to garbage value. Use calloc instead of malloc in expr_ctx_new() to fix this. Fixes: 3340a08354ac286e ("perf pmu-events: Fix testing with JEVENTS_ARCH=all") Reviewed-by: Ian Rogers Reviewed-by: James Clark Signed-off-by: Levi Yun Cc: Mark Rutland Cc: Namhyung Kim Link: https://lore.kernel.org/r/20241108143424.819126-1-yeoreum.yun@arm.com Signed-off-by: Arnaldo Carvalho de Melo

perf header: Pass a perf_cpu rather than a PMU to get_cpuid_str

2024-11-16T19:40:30+00:00

On ARM the cpuid is dependent on the core type of the CPU in question. The PMU was passed for the sake of the CPU map but this means in places a temporary PMU is created just to pass a CPU value. Just pass the CPU and fix up the callers. As there are no longer PMU users in header.h, shuffle forward declarations earlier to work around build failures. Reviewed-by: James Clark Signed-off-by: Ian Rogers Tested-by: Xu Yang Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Athira Rajeev Cc: Ben Zong-You Xie Cc: Benjamin Gray Cc: Bibo Mao Cc: Clément Le Goffic Cc: Dima Kogan Cc: Dr. David Alan Gilbert Cc: Huacai Chen Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mike Leach Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sandipan Das Cc: Will Deacon Cc: Yicong Yang Cc: linux-arm-kernel@lists.infradead.org Cc: linux-riscv@lists.infradead.org Link: https://lore.kernel.org/r/20241107162035.52206-7-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tool_pmu: Move expr literals to tool_pmu

2024-10-11T06:40:32+00:00

Add the expr literals like "#smt_on" as tool events, this allows stat events to give the values. On my laptop with hyperthreading enabled: ``` $ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true Performance counter stats for 'true': 0 has_pmem 8 num_cores 16 num_cpus 16 num_cpus_online 1 num_dies 1 num_packages 1 smt_on 2,496,000,000 system_tsc_freq 0.001113637 seconds time elapsed 0.001218000 seconds user 0.000000000 seconds sys ``` And with hyperthreading disabled: ``` $ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true Performance counter stats for 'true': 0 has_pmem 8 num_cores 16 num_cpus 8 num_cpus_online 1 num_dies 1 num_packages 0 smt_on 2,496,000,000 system_tsc_freq 0.000802115 seconds time elapsed 0.000000000 seconds user 0.000806000 seconds sys ``` As zero matters for these values, in stat-display should_skip_zero_counter only skip the zero value if it is not the first aggregation index. The tool event implementations are used in expr but not evaluated as events for simplicity. Also core_wide isn't made a tool event as it requires command line parameters. Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Link: https://lore.kernel.org/r/20241002032016.333748-8-irogers@google.com Signed-off-by: Namhyung Kim