kernel/linux.git/tools/perf/util/target.c, branch v6.18.22

perf target: Remove uid from target

2025-06-09T18:18:18+00:00

Gathering threads with a uid by scanning /proc is inherently racy leading to perf_event_open failures that quit perf. All users of the functionality now use BPF filters, so remove uid and uid_str from target. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250604174545.2853620-10-irogers@google.com Signed-off-by: Namhyung Kim

perf target: Separate parse_uid into its own function

2025-06-09T18:18:17+00:00

Allow parse_uid to be called without a struct target. Rather than have two errors, remove TARGET_ERRNO__USER_NOT_FOUND and use TARGET_ERRNO__INVALID_UID as the handling is identical. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250604174545.2853620-3-irogers@google.com Signed-off-by: Namhyung Kim

perf stat: Enable counting events for BPF programs

2021-01-20T17:25:28+00:00

Introduce 'perf stat -b' option, which counts events for BPF programs, like: [root@localhost ~]# ~/perf stat -e ref-cycles,cycles -b 254 -I 1000 1.487903822 115,200 ref-cycles 1.487903822 86,012 cycles 2.489147029 80,560 ref-cycles 2.489147029 73,784 cycles 3.490341825 60,720 ref-cycles 3.490341825 37,797 cycles 4.491540887 37,120 ref-cycles 4.491540887 31,963 cycles The example above counts 'cycles' and 'ref-cycles' of BPF program of id 254. This is similar to bpftool-prog-profile command, but more flexible. 'perf stat -b' creates per-cpu perf_event and loads fentry/fexit BPF programs (monitor-progs) to the target BPF program (target-prog). The monitor-progs read perf_event before and after the target-prog, and aggregate the difference in a BPF map. Then the user space reads data from these maps. A new 'struct bpf_counter' is introduced to provide a common interface that uses BPF programs/maps to count perf events. Committer notes: Removed all but bpf_counter.h includes from evsel.h, not needed at all. Also BPF map lookups for PERCPU_ARRAYs need to have as its value receive buffer passed to the kernel libbpf_num_possible_cpus() entries, not evsel__nr_cpus(evsel), as the former uses /sys/devices/system/cpu/possible while the later uses /sys/devices/system/cpu/online, which may be less than the 'possible' number making the bpf map lookup overwrite memory and cause hard to debug memory corruption. We need to continue using evsel__nr_cpus(evsel) when accessing the perf_counts array tho, not to overwrite another are of memory :-) Signed-off-by: Song Liu Tested-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/lkml/20210120163031.GU12699@kernel.org/ Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Peter Zijlstra Cc: kernel-team@fb.com Link: http://lore.kernel.org/lkml/20201229214214.3413833-4-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove util.h from where it is not needed

2019-09-20T12:19:20+00:00

Check that it is not needed and remove, fixing up some fallout for places where it was only serving to get something else. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-9h6dg6lsqe2usyqjh5rrues4@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove debug.h from places where it is not needed

2019-09-20T12:19:20+00:00

Pruning a bit more the includes dependency tree. Building this thing on lots of containers takes time, we better reduce the time per build, each container is doing 6 builds when clang and clang-devel are available, and the plan is to do a 'make -C tools/perf build-test' that have many more. Also helps when doing normal development, as touching some random file will have a much reduced chance of triggering lots of rebuilds. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-r889ur2cxe16m91m2a4pl15p@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf debug: Remove needless include directives from debug.h

2019-08-31T22:10:19+00:00

All we need there is a forward declaration for 'union perf_event', so remove it from there and add missing header directives in places using things from this indirect include. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-7ftk0ztstqub1tirjj8o8xbl@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add missing headers, mostly stdlib.h

2019-07-09T13:13:22+00:00

Part of the erosion of util/util.h, that will lose its include stdlib.h, we need to add it to places where it is needed but was getting it indirectly. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-1imnqezw99ahc07fjeb51qby@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 433

2019-06-05T15:37:16+00:00

Based on 1 normalized pattern(s): released under the gpl v2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Armijn Hemel Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190114.749096322@linutronix.de Signed-off-by: Greg Kroah-Hartman

perf target: str_error_r() always returns the buffer it receives

2016-07-29T14:54:35+00:00

So no need for checking if it uses the strerror_r() GNU variant error reporting mechanism, i.e. if it returns a pointer to a immutable string internal to glibc. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Fixes: c8b5f2c96d1b ("tools: Introduce str_error_r()") Link: http://lkml.kernel.org/n/tip-xr83cd4y4r3cn6tq6w4f59jb@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Remove needless includes from cache.h

2016-07-12T18:19:58+00:00

The cache.h header doesn't use any of the definitions in some of the headers it includes, ditch them and fix the fallout, where files were getting stuff they needed just because they were including it, sometimes not using what it really exports at all. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-l6r2bmj8h1g3e01wr981on0n@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo