kernel/linux.git/tools/perf/builtin-record.c, branch v7.2-rc5

perf tools: NULL bitmap pointers after bitmap_free()

2026-06-10T16:13:32+00:00

Two call sites free bitmaps without NULLing the pointer, risking double-free if the structure is reused or cleanup is called twice: - mmap__munmap(): map->affinity_mask.bits - record__mmap_cpu_mask_free(): mask->bits Set each pointer to NULL after bitmap_free(). Fixes: 8384a2600c7ddfc8 ("perf record: Adapt affinity to machines with #CPUs > 1K") Fixes: f466e5ed6c356d1d ("perf record: Extend --threads command line option") Reported-by: sashiko-bot Reviewed-by: Ian Rogers Cc: Alexey Budankov Cc: Alexey Bayduraev Cc: Arnaldo Carvalho de Melo Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo

perf zstd: Fix compression error path in zstd_compress_stream_to_records()

2026-05-29T14:44:23+00:00

The error fallback does memcpy(dst, src, src_size) intending to store uncompressed data when compression fails, but this has three bugs: 1. dst has been advanced past the record header (and potentially past earlier compressed records), so the copy writes to the wrong offset in the output buffer. 2. src still points to the start of the input, not to the remaining uncompressed data at src + input.pos. On a second or later iteration, previously compressed data would be duplicated. 3. No check that dst_size >= src_size — if the remaining output space is smaller, this is an out-of-bounds write. Replace with return -1 after resetting the ZSTD compression context via ZSTD_initCStream(). The -1 propagates through zstd_compress() -> record__pushfn() -> perf_mmap__push() to the recording loop, which breaks out and terminates recording. Add an out_child_no_flush label in __cmd_record() so the mmap-read failure path skips the final record__mmap_read_all() flush — retrying the same read that just failed would just fail again, and the flush is only useful when the mmap data is intact but the control path (auxtrace, switch_output) had an error. Consolidate all error paths through a single 'reset' label to ensure the compression context is always reset on failure — including the output-buffer-full path, where a bare return without resetting would leave stale stream state that corrupts output if the caller retries. Also guard against process_header() writing the event header before the buffer-full check: add a sizeof(perf_event_header) pre-check so the callback never writes past the output buffer. Guard against ZSTD making no progress: if output.pos is zero after ZSTD_compressStream(), calling process_header(record, 0) would re-trigger header initialization, double-subtracting the header size from dst_size and underflowing the unsigned counter. Also fix two pre-existing issues in the same function: - Add a dst_size guard before subtracting the record header size: if the output buffer is nearly full, the unsigned dst_size -= size underflows to a huge value, causing ZSTD_compressStream to write past the buffer boundary. - Check the ZSTD_initCStream() return value and log an error if the context reset itself fails. Reported-by: sashiko-bot@kernel.org # Running on a local machine Reviewed-by: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Assisted-by: Claude:claude-opus-4.6-1m Signed-off-by: Arnaldo Carvalho de Melo

powerpc tools perf: Initialize error code in auxtrace_record_init function

2026-05-27T11:08:53+00:00

perf trace record fails some cases in powerpc # perf test "perf trace record and replay" 128: perf trace record and replay : FAILED! # perf trace record sleep 1 # echo $? 32 This is happening because of non-zero err value from auxtrace_record__init() function. static int record__auxtrace_init(struct record *rec) { int err; if ((rec->opts.auxtrace_snapshot_opts || rec->opts.auxtrace_sample_opts) && record__threads_enabled(rec)) { pr_err("AUX area tracing options are not available in parallel streaming mode.\n"); return -EINVAL; } if (!rec->itr) { rec->itr = auxtrace_record__init(rec->evlist, &err); if (err) return err; } Here "int err" is not initialised. The code expects "err" to be set from auxtrace_record__init() function. Update auxtrace_record__init() in arch/powerpc/util/auxtrace.c to clear err value in the beginning. - Clear err value in beginning of function. Any fail later will set appropriate return code to err. - Even if we haven't found any event for auxtrace, perf record should continue for other events. NULL return will indicate that there is no auxtrace record initialized. - Not having "err" set here will affect monitoring of other events also because perf record will fail seeing random value in err. Set err to -EINVAL before invoking auxtrace_record__init() in builtin-record.c With the fix, # perf trace record sleep 1 [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.033 MB perf.data (228 samples) ] Fixes: 1dbfaf94cf66ec4b ("perf powerpc: Add basic CONFIG_AUXTRACE support for VPA pmu on powerpc") Reviewed-by: Adrian Hunter Signed-off-by: Athira Rajeev Acked-by: Namhyung Kim Cc: Athira Rajeev Cc: Hari Bathini Cc: Ian Rogers Cc: Jiri Olsa Cc: linuxppc-dev@lists.ozlabs.org Cc: Madhavan Srinivasan Cc: Michael Petlan Cc: Shivani Nittor Cc: Tanushree Shah Cc: Tejas Manhas Cc: Thomas Richter Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Remove evsel from tool APIs that pass the sample

2026-05-20T19:34:23+00:00

As struct perf_sample now directly contains its own resolved evsel pointer, passing the evsel separately is redundant and clutters the interface. Remove the redundant evsel parameter from tool-specific handlers and structures, ensuring the tool always directly accesses the evsel bound to the sample. This simplifies the API signatures and eliminates the risk of passing an inconsistent evsel. Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chen Ni Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Derek Foreman Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Howard Chu Cc: Hrishikesh Suresh Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Krzysztof Łopatowski Cc: Leo Yan Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Ravi Bangoria Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Tianyou Li Cc: Yujie Liu Cc: tanze [ Fixed up conflict with "perf inject: Fix itrace branch stack synthesis" series ] Signed-off-by: Arnaldo Carvalho de Melo

perf record: Refactor ARM64 leaf caller setup out of arch

2026-05-14T23:50:00+00:00

Code in tools/perf/arch causes portability issues/opaqueness and LTO issues due to the use of weak symbols. Move the adding of LR to the sample_user_regs into arm64-frame-pointer-unwind-support.c conditional on EM_HOST == EM_AARCH64 (false on all non-ARM64 builds). This also better encapsulates the use of the sampled registers by get_leaf_frame_caller_aarch64 and the set up by the new add_leaf_frame_caller_opts_aarch64, exposing opportunities for possibly sampling PC and SP to help the unwinder. Reviewed-by: James Clark Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Dapeng Mi Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Mike Leach Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Shimin Guo Cc: Will Deacon Signed-off-by: Arnaldo Carvalho de Melo

perf data: Clean up use_stdio and structures

2026-04-09T02:21:17+00:00

use_stdio was associated with struct perf_data and not perf_data_file meaning there was implicit use of fd rather than fptr that may not be safe. For example, in perf_data_file__write. Reorganize perf_data_file to better abstract use_stdio, add kernel-doc and more consistently use perf_data__ accessors so that use_stdio is better respected. Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf tools: Use calloc() where applicable

2026-04-09T02:21:05+00:00

Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc() does. In some places where linux/zalloc.h isn't needed, remove it, add when needed and was getting it indirectly. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim

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 evlist: Improve default event for s390

2026-03-19T21:42:46+00:00

Frame pointer callchains are not supported on s390 and dwarf callchains are only supported on software events. Switch the default event from the hardware 'cycles' event to the software 'cpu-clock' or 'task-clock' on s390 if callchains are enabled. Move some of the target initialization earlier in builtin-top and builtin-record, so it is ready for use by evlist__new_default. If frame pointer callchains are requested on s390 show a warning. Modify the '-g' option of `perf top` and `perf record` to default to dwarf callchains on s390. Signed-off-by: Ian Rogers Tested-by: Thomas Richter Signed-off-by: Namhyung Kim

perf callchain: Refactor callchain option parsing

2026-03-19T21:42:46+00:00

record_opts__parse_callchain is shared by builtin-record and builtin-trace, it is declared in callchain.h. Move the declaration to callchain.c for consistency with the header. In other cases make the option callback a small static stub that then calls into callchain.c. Make the no argument '-g' callchain option just a short-cut for '--call-graph fp' so that there is consistency in how the arguments are handled. This requires the const char* string to be strdup-ed in __parse_callchain_report_opt. For consistency also make parse_callchain_record use strdup and remove some unnecessary casts. Also, be more explicit about the '-g' behavior if there is a .perfconfig file setting. Signed-off-by: Ian Rogers Tested-by: Thomas Richter Signed-off-by: Namhyung Kim