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

libperf cpumap: Make index and nr types unsigned

2026-04-01T21:50:53+00:00

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 Closes: https://lore.kernel.org/lkml/20260212025127.841090-1-liqb365@163.com/ Tested-by: Chingbin Li Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf header: Support CPU DOMAIN relation info

2026-01-22T00:55:09+00:00

The '/proc/schedstat' file gives info about load balancing statistics within a given domain. It also contains the cpu_mask giving information about the sibling cpus and domain names after schedstat version 17. Storing this information in perf header will help tools like `perf sched stats` for better analysis. Signed-off-by: Swapnil Sapkal Tested-by: Chen Yu Acked-by: Ian Rogers Acked-by: Namhyung Kim Acked-by: Peter Zijlstra Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Anubhav Shelat Cc: Ben Gainey Cc: Blake Jones Cc: Chun-Tse Shao Cc: David Vernet Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Gautham Shenoy Cc: Graham Woodward Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Juri Lelli Cc: K Prateek Nayak Cc: Kan Liang Cc: Leo Yan Cc: Madadi Vineeth Reddy Cc: Mark Rutland Cc: Ravi Bangoria Cc: Sandipan Das Cc: Santosh Shukla Cc: Shrikanth Hegde Cc: Steven Rostedt (VMware) Cc: Tejun Heo Cc: Thomas Falcon Cc: Tim Chen Cc: Vincent Guittot Cc: Yang Jihong Cc: Yujie Liu Cc: Zhongqiu Han Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add helper x86__is_intel_cpu()

2025-10-02T18:31:14+00:00

Add helper x86__is_intel_cpu() to indicate if it's a x86 intel platform. Signed-off-by: Dapeng Mi Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Kan Liang Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf env: Remove global perf_env

2025-07-25T17:37:58+00:00

The global perf_env was used for the host, but if a perf_env wasn't easy to come by it was used in a lot of places where potentially recorded and host data could be confused. Remove the global variable as now the majority of accesses retrieve the perf_env for the host from the session. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-20-irogers@google.com Signed-off-by: Namhyung Kim

perf test: Avoid use perf_env

2025-07-25T17:37:57+00:00

The perf_env global variable holds the host perf_env data but its use is hit and miss. Switch to using local perf_env variables and ensure scoped perf_env__init and perf_env__exit. This loses command line setting of the perf_env, but this doesn't matter for tests. So the perf_env is fully initialized, clear it with memset in perf_env__init. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-13-irogers@google.com Signed-off-by: Namhyung Kim

perf top: populate PMU capabilities data in perf_env

2025-06-26T17:51:40+00:00

Calling perf top with branch filters enabled on Intel CPU's with branch counters logging (A.K.A LBR event logging [1]) support results in a segfault. $ perf top -e '{cpu_core/cpu-cycles/,cpu_core/event=0xc6,umask=0x3,frontend=0x11,name=frontend_retired_dsb_miss/}' -j any,counter ... Thread 27 "perf" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffafff76c0 (LWP 949003)] perf_env__find_br_cntr_info (env=0xf66dc0 , nr=0x0, width=0x7fffafff62c0) at util/env.c:653 653 *width = env->cpu_pmu_caps ? env->br_cntr_width : (gdb) bt #0 perf_env__find_br_cntr_info (env=0xf66dc0 , nr=0x0, width=0x7fffafff62c0) at util/env.c:653 #1 0x00000000005b1599 in symbol__account_br_cntr (branch=0x7fffcc3db580, evsel=0xfea2d0, offset=12, br_cntr=8) at util/annotate.c:345 #2 0x00000000005b17fb in symbol__account_cycles (addr=5658172, start=5658160, sym=0x7fffcc0ee420, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:389 #3 0x00000000005b1976 in addr_map_symbol__account_cycles (ams=0x7fffcd7b01d0, start=0x7fffcd7b02b0, cycles=539, evsel=0xfea2d0, br_cntr=8) at util/annotate.c:422 #4 0x000000000068d57f in hist__account_cycles (bs=0x110d288, al=0x7fffafff6540, sample=0x7fffafff6760, nonany_branch_mode=false, total_cycles=0x0, evsel=0xfea2d0) at util/hist.c:2850 #5 0x0000000000446216 in hist_iter__top_callback (iter=0x7fffafff6590, al=0x7fffafff6540, single=true, arg=0x7fffffff9e00) at builtin-top.c:737 #6 0x0000000000689787 in hist_entry_iter__add (iter=0x7fffafff6590, al=0x7fffafff6540, max_stack_depth=127, arg=0x7fffffff9e00) at util/hist.c:1359 #7 0x0000000000446710 in perf_event__process_sample (tool=0x7fffffff9e00, event=0x110d250, evsel=0xfea2d0, sample=0x7fffafff6760, machine=0x108c968) at builtin-top.c:845 #8 0x0000000000447735 in deliver_event (qe=0x7fffffffa120, qevent=0x10fc200) at builtin-top.c:1211 #9 0x000000000064ccae in do_flush (oe=0x7fffffffa120, show_progress=false) at util/ordered-events.c:245 #10 0x000000000064d005 in __ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP, timestamp=0) at util/ordered-events.c:324 #11 0x000000000064d0ef in ordered_events__flush (oe=0x7fffffffa120, how=OE_FLUSH__TOP) at util/ordered-events.c:342 #12 0x00000000004472a9 in process_thread (arg=0x7fffffff9e00) at builtin-top.c:1120 #13 0x00007ffff6e7dba8 in start_thread (arg=) at pthread_create.c:448 #14 0x00007ffff6f01b8c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78 The cause is that perf_env__find_br_cntr_info tries to access a null pointer pmu_caps in the perf_env struct. A similar issue exists for homogeneous core systems which use the cpu_pmu_caps structure. Fix this by populating cpu_pmu_caps and pmu_caps structures with values from sysfs when calling perf top with branch stack sampling enabled. [1], LBR event logging introduced here: https://lore.kernel.org/all/20231025201626.3000228-5-kan.liang@linux.intel.com/ Reviewed-by: Ian Rogers Signed-off-by: Thomas Falcon Link: https://lore.kernel.org/r/20250612163659.1357950-2-thomas.falcon@intel.com Signed-off-by: Namhyung Kim

perf record: collect BPF metadata from new programs

2025-06-20T21:48:49+00:00

This collects metadata for any BPF programs that were loaded during a "perf record" run, and emits it at the end of the run. Signed-off-by: Blake Jones Link: https://lore.kernel.org/r/20250612194939.162730-4-blakejones@google.com Signed-off-by: Namhyung Kim

perf cpumap: Reduce cpu size from int to int16_t

2025-02-27T16:47:25+00:00

Fewer than 32k logical CPUs are currently supported by perf. A cpumap is indexed by an integer (see perf_cpu_map__cpu) yielding a perf_cpu that wraps a 4-byte int for the logical CPU - the wrapping is done deliberately to avoid confusing a logical CPU with an index into a cpumap. Using a 4-byte int within the perf_cpu is larger than required so this patch reduces it to the 2-byte int16_t. For a cpumap containing 16 entries this will reduce the array size from 64 to 32 bytes. For very large servers with lots of logical CPUs the size savings will be greater. Signed-off-by: Ian Rogers Reviewed-by: James Clark Link: https://lore.kernel.org/r/20250210191231.156294-1-irogers@google.com Signed-off-by: Namhyung Kim

perf tools: Remove dependency on libaudit

2025-01-10T13:59:42+00:00

All architectures now support HAVE_SYSCALL_TABLE_SUPPORT, so the flag is no longer needed. With the removal of the flag, the related GENERIC_SYSCALL_TABLE can also be removed. libaudit was only used as a fallback for when HAVE_SYSCALL_TABLE_SUPPORT was not defined, so libaudit is also no longer needed for any architecture. Signed-off-by: Charlie Jenkins Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Arnd Bergmann Cc: Christian Brauner Cc: Guo Ren Cc: Günther Noack Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Jonathan Corbet Cc: Leo Yan Cc: Mark Rutland Cc: Mickaël Salaün Cc: Mike Leach Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Will Deacon Link: https://lore.kernel.org/r/20250108-perf_syscalltbl-v6-16-7543b5293098@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo

perf env: Move arch errno function to only use in env

2024-12-18T19:24:33+00:00

Move arch_syscalls__strerrno_function out of builtin-trace.c to env.c so that there isn't a util to builtin function call. This allows the python.c stub to be removed. Also, remove declaration/prototype from env.h and make static to reduce scope. The include is moved inside ifdefs to avoid, "defined but unused warnings". Signed-off-by: Ian Rogers Acked-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Colin Ian King Cc: Dapeng Mi Cc: Howard Chu Cc: Ilya Leoshkevich Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Thomas Richter Cc: Veronika Molnarova Cc: Weilin Wang Link: https://lore.kernel.org/r/20241119011644.971342-15-irogers@google.com perf: perf python: Correctly throw IndexError Signed-off-by: Arnaldo Carvalho de Melo