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

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

perf sample: Add evsel to struct perf_sample

2026-04-06T06:12:15+00:00

Add the evsel from evsel__parse_sample into the struct perf_sample. Sometimes we want to alter the evsel associated with a sample, such as with off-cpu bpf-output events. In general the evsel and perf_sample are passed as a pair, but this makes an altered evsel something of a chore to keep checking for and setting up. Later patches will remove passing an evsel with the perf_sample and switch to just using the perf_sample's value. Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf sample: Make sure perf_sample__init/exit are used

2026-04-06T06:12:15+00:00

The deferred stack trace code wasn't using perf_sample__init/exit. Add the deferred stack trace clean up to perf_sample__exit which requires proper NULL initialization in perf_sample__init. Make the perf_sample__exit robust to being called more than once by using zfree. Make the error paths in evsel__parse_sample exit the sample. Add a merged_callchain boolean to capture that callchain is allocated, deferred_callchain doen't suffice for this. Pack the struct variables to avoid padding bytes for this. Similiarly powerpc_vpadtl_sample wasn't using perf_sample__init/exit, use it for consistency and potential issues with uninitialized variables. Similarly guest_session__inject_events in builtin-inject wasn't using perf_sample_init/exit. The lifetime management for fetched events is somewhat complex there, but when an event is fetched the sample should be initialized and needs exiting on error. The sample may be left in place so that future injects have access to it. Signed-off-by: Ian Rogers Signed-off-by: Namhyung Kim

perf session: Extra logging for failed to process events

2026-04-03T02:35:16+00:00

Print log information in ordered event processing so that the cause of finished round failing is clearer. Print the event name along with its number when an event isn't processed. Add extra detail about where the failure happened. The following log lines come from running `perf data convert`. Before: 0xa250 [0x10]: failed to process type: 80 After: 0xa250 [0x10]: piped event processing failed for event of type: FEATURE (80) Signed-off-by: Ian Rogers 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 thread: Don't require machine to compute the e_machine

2026-02-03T21:01:27+00:00

The machine can be calculated from a thread via its maps. Don't require the machine argument to simplify callers and also to delay computing the machine until a little later. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf header: Add e_machine/e_flags to the header

2026-02-03T21:01:27+00:00

Add 64-bits of feature data to record the ELF machine and flags. This allows readers to initialize based on the data. For example, `perf kvm stat` wants to initialize based on the kind of data to be read, but at initialization time there are no threads to base this data upon and using the host means cross platform support won't work. The values in the perf_env also act as a cache for these within the session. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf session: Add e_flags to the e_machine helper

2026-02-03T21:01:27+00:00

Allow e_flags as well as e_machine to be computed using the e_machine helper. This isn't currently used, the argument is always NULL, but it will be used for a new header feature. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf session: Don't write to memory pointed to a const pointer

2026-01-27T05:09:37+00:00

Since it is freshly allocated just attribute it to a non-const pointer and then change it via that pointer. That way we avoid const-correctness warnings in recent glibc versions. Signed-off-by: Arnaldo Carvalho de Melo