linux.git/tools/perf/util/scripting-engines/trace-event-python.c, branch v7.2-rc2

perf symbol: Add setters for bitfields sharing a byte to avoid concurrent update issues

2026-06-03T19:53:45+00:00

A problem with putting bitfields into struct symbol is that other bits in
the symbol could be updated concurrently and only one update to the
underlying storage unit happen, leading to lost updates.

To avoid this, use atomics to atomically read or set part of 16-bits
of flags in the symbol. Add accessors to simplify this.

The idle value has 3 values in preparation for a later change that
will lazily update it.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers 
Acked-by: Namhyung Kim 
Cc: Alexander Gordeev 
Cc: Heiko Carstens 
Cc: Honglei Wang 
Cc: Jan Polensky 
Cc: Sumanth Korikkar 
Cc: Thomas Richter 
Cc: Vasily Gorbik 
Signed-off-by: Arnaldo Carvalho de Melo

perf auxtrace: Harden auxtrace_error event handling

2026-05-29T14:44:33+00:00

Fix four issues in PERF_RECORD_AUXTRACE_ERROR handling:

1. auxtrace_error_name() takes a signed int parameter, but e->type
   is __u32.  A crafted value like 0xFFFFFFFF converts to -1, passes
   the bounds check, and causes a negative array index.  Fix by
   changing the parameter to unsigned int.

2. The msg field is printed via %s without a length bound.  The
   min_size table only guarantees fields up to msg (offset 48), so
   a truncated event has zero msg bytes within the event boundary.
   Compute the available msg length from header.size, cap at
   sizeof(e->msg), and use %.*s.

3. fmt >= 2 adds machine_pid and vcpu fields after msg[64].  Older
   files may have fmt >= 2 but an event size that doesn't include
   these fields.  Add a size check in the swap handler to downgrade
   fmt before the conditional field access, and a matching size
   guard in the fprintf path for native-endian events (which are
   mmap'd read-only and can't be modified in place).

4. python_process_auxtrace_error() had the same issues: msg was
   passed to tuple_set_string() unbounded, and machine_pid/vcpu
   were accessed unconditionally without checking fmt or event
   size.  Apply the same bounds checks.

Reported-by: sashiko-bot@kernel.org # Running on a local machine
Reviewed-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Assisted-by: Claude:claude-opus-4.6-1m
Signed-off-by: Arnaldo Carvalho de Melo

perf script: Don't pass evsel with sample

2026-05-20T19:39:40+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 script-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 
Signed-off-by: Arnaldo Carvalho de Melo

perf db-export: Remove evsel from struct export_sample

2026-05-20T19:35:59+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 db-export-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 
Signed-off-by: Arnaldo Carvalho de Melo

perf callchain: Don't pass evsel and sample

2026-05-20T19:35:59+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 callchain-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 
Signed-off-by: Arnaldo Carvalho de Melo

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 perf_regs: Accurately compute register names for CSKY

2026-01-26T21:31:16+00:00

CSKY needs the e_flags to determine the ABI level and know whether
additional registers are encoded or not. Wire this up now that the
e_flags for a thread can be determined.

Signed-off-by: Ian Rogers 
Cc: Aditya Bodkhe 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Chun-Tse Shao 
Cc: Guo Ren 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Sergei Trofimovich 
Cc: Shimin Guo 
Cc: Stephen Brennan 
Cc: Swapnil Sapkal 
Cc: Tianyou Li 
[ Conditionally define EF_CSKY_ABIMASK and EF_CSKY_ABIV2 for older distros ]
Signed-off-by: Arnaldo Carvalho de Melo

perf thread: Add optional e_flags output argument to thread__e_machine

2026-01-26T21:21:20+00:00

The e_flags are needed to accurately compute complete perf register
information for CSKY.

Add the ability to read and have this value associated with a thread.

This change doesn't wire up the use of the e_flags except in disasm
where use already exists but just wasn't set up yet.

Signed-off-by: Ian Rogers 
Cc: Aditya Bodkhe 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Chun-Tse Shao 
Cc: Guo Ren 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Sergei Trofimovich 
Cc: Shimin Guo 
Cc: Stephen Brennan 
Cc: Swapnil Sapkal 
Cc: Tianyou Li 
Signed-off-by: Arnaldo Carvalho de Melo

perf perf_regs: Switch from arch string to int e_machine

2026-01-20T18:43:04+00:00

The arch string requires multiple strcmp to identify things like the
IP and SP.

Switch to passing in an e_machine that in the bulk of cases is computed
using a current thread load.

The e_machine also allows identification of 32-bit vs 64-bit processes.

Signed-off-by: Ian Rogers 
Cc: Aditya Bodkhe 
Cc: Adrian Hunter 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Chun-Tse Shao 
Cc: Dmitriy Vyukov 
Cc: Dr. David Alan Gilbert 
Cc: Guo Ren 
Cc: Haibo Xu 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Krzysztof Łopatowski 
Cc: Leo Yan 
Cc: Mark Wielaard 
Cc: Namhyung Kim 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Sergei Trofimovich 
Cc: Shimin Guo 
Cc: Stephen Brennan 
Cc: Thomas Falcon 
Cc: Will Deacon 
[ Include dwarf-regs.h to get conditional defines for EM_CSKY and EM_LOONGARCH, not available in old distros ]
Signed-off-by: Arnaldo Carvalho de Melo