linux.git/tools/lib/perf/threadmap.c, branch v6.18.21

libperf threadmap: Add perf_thread_map__idx()

2025-05-21T18:07:13+00:00

Allow computation of thread map index from a PID.

Note, with a 'struct perf_cpu_map' the sorted nature allows for a binary
search to compute the index which isn't currently possible with a
'struct perf_thread_map' as they aren't guaranteed sorted.

Signed-off-by: Ian Rogers 
Acked-by: Gautam Menghani 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20250519195148.1708988-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf threadmap: Don't segv for index 0 for the NULL 'struct perf_thread_map' pointer

2025-05-21T18:07:13+00:00

perf_thread_map__nr() returns length 1 if the perf_thread_map is NULL,
meaning index 0 is valid.

When perf_thread_map__pid() of index 0 is read then return the expected
"any" -1 value.

Assert this is only done for index 0.

Signed-off-by: Ian Rogers 
Acked-by: Gautam Menghani 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Howard Chu 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Madhavan Srinivasan 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20250519195148.1708988-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Add API for allocating new thread map array

2022-02-23T17:40:23+00:00

The existing API perf_thread_map__new_dummy() allocates new thread map
for one thread. I couldn't find a way to reallocate the map with more
threads, or to allocate a new map for more than one thread.

Having multiple threads in a thread map is essential for some use cases.
That's why a new API is proposed, which allocates a new thread map for
given number of threads: perf_thread_map__new_array()

Signed-off-by: Tzvetomir Stoyanov (VMware) 
Acked-by: Jiri Olsa 
Cc: Ian Rogers 
Link: https://lore.kernel.org/linux-perf-users/20220221102628.43904-1-tz.stoyanov@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Rename arguments of perf_thread_map APIs

2022-02-23T17:39:29+00:00

The "int thread" input arguments of some perf_thead_map APIs are index
of the thread in the thread map.

In order to avoid confusion and to make the APIs consistent with
perf_cpu_map APIs, those arguments are renamed to "int idx".

Suggested-by: Arnaldo Carvalho de Melo 
Signed-off-by: Tzvetomir Stoyanov (VMware) 
Acked-by: Jiri Olsa 
Cc: Ian Rogers 
Link: https://lore.kernel.org/r/20220221102612.43879-1-tz.stoyanov@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo

libperf: Move to tools/lib/perf

2020-01-06T14:46:09+00:00

Move libperf from its current location under tools/perf to a separate
directory under tools/lib/.

Also change various paths (mainly includes) to reflect the libperf move
to a separate directory and add a new directory under MANIFEST.

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20191206210612.8676-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo