kernel/tools/perf/bench/futex.c, branch linux-rolling-stable

perf auxtrace: Remove errno.h from auxtrace.h and fix transitive dependencies

2025-11-14T07:03:11Z

errno.h isn't used in auxtrace.h so remove it and fix build failures caused by transitive dependencies through auxtrace.h on errno.h. Signed-off-by: Ian Rogers Reviewed-by: James Clark Signed-off-by: Namhyung Kim

perf bench futex: Remove support for IMMUTABLE

2025-07-11T14:02:01Z

It has been decided to remove the support IMMUTABLE futex. perf bench was one of the eary users for testing purposes. Now that the API is removed before it could be used in an official release, remove the bits from perf, too. Remove Remove support for IMMUTABLE futex. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250710110011.384614-7-bigeasy@linutronix.de

perf bench futex: Fix prctl include in musl libc

2025-06-17T21:29:42Z

Namhyung Kim reported: I've updated the perf-tools-next to v6.16-rc1 and found a build error like below on alpine linux 3.18. In file included from bench/futex.c:6: /usr/include/sys/prctl.h:88:8: error: redefinition of 'struct prctl_mm_map' 88 | struct prctl_mm_map { | ^~~~~~~~~~~~ In file included from bench/futex.c:5: /linux/tools/include/uapi/linux/prctl.h:134:8: note: originally defined here 134 | struct prctl_mm_map { | ^~~~~~~~~~~~ make[4]: *** [/linux/tools/build/Makefile.build:86: /build/bench/futex.o] Error 1 git bisect says it's the first commit introduced the failure. So both /usr/include/sys/prctl.h and /linux/tools/include/uapi/linux/prctl.h provide struct prctl_mm_map but their include guard must be different. /usr/include/sys/prctl.h provided by glibc contains the prctl() declaration. It includes also linux/prctl.h. The /usr/include/sys/prctl.h on alpine linux is different. This is probably coming from musl. It contains the PR_* definition and the prctl() declaration. So it clashes here because now the one struct is available twice. The man page for prctl(2) says: | #include /* Definition of PR_* constants */ | #include so musl doesn't follow this. So don't include linux/prctl.h explicitely and add some new defines needed if they aren't available. Acked-by: Sebastian Andrzej Siewior Reported-by: Namhyung Kim Closes: https://lore.kernel.org/r/20250611092542.F4ooE2FL@linutronix.de Link: https://www.openwall.com/lists/musl/2025/06/12/11 Signed-off-by: Arnaldo Carvalho de Melo

tools headers: Synchronize prctl.h ABI header

2025-05-21T11:57:41Z

The prctl.h ABI header was slightly updated during the development of the interface. In particular the "immutable" parameter became a bit in the option argument. Synchronize prctl.h ABI header again and make use of the definition in the testsuite and "perf bench futex". Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: André Almeida Link: https://lore.kernel.org/r/20250517151455.1065363-5-bigeasy@linutronix.de

tools/perf: Allow to select the number of hash buckets

2025-05-03T10:02:10Z

Add the -b/ --buckets argument to specify the number of hash buckets for the private futex hash. This is directly passed to prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_SET_SLOTS, buckets, immutable) and must return without an error if specified. The `immutable' is 0 by default and can be set to 1 via the -I/ --immutable argument. The size of the private hash is verified with PR_FUTEX_HASH_GET_SLOTS. If PR_FUTEX_HASH_GET_SLOTS failed then it is assumed that an older kernel was used without the support and that the global hash is used. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250416162921.513656-20-bigeasy@linutronix.de