[PATCH 1/1 fyi] tools headers UAPI: Sync linux/prctl.h with the kernel sources to pick FUTEX knob
From: Arnaldo Carvalho de Melo
Date: Tue Jun 10 2025 - 16:40:35 EST
tldr; Just FYI, I'm carrying this on the perf tools tree.
Full explanation:
There used to be no copies, with tools/ code using kernel headers
directly. From time to time tools/perf/ broke due to legitimate kernel
hacking. At some point Linus complained about such direct usage. Then we
adopted the current model.
See further details at:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/tools/include/uapi/README
To pick the changes in:
63e8595c060a1fef ("futex: Allow to make the private hash immutable")
80367ad01d93ac78 ("futex: Add basic infrastructure for local task local hash")
That adds a FUTEX knob:
$ tools/perf/trace/beauty/prctl_option.sh > before
$ cp include/uapi/linux/prctl.h tools/perf/trace/beauty/include/uapi/linux/prctl.h
$ tools/perf/trace/beauty/prctl_option.sh > after
$ diff -u before after
--- before 2025-06-09 14:50:45.162579336 -0300
+++ after 2025-06-09 14:50:52.797660024 -0300
@@ -72,6 +72,7 @@
[75] = "SET_SHADOW_STACK_STATUS",
[76] = "LOCK_SHADOW_STACK_STATUS",
[77] = "TIMER_CREATE_RESTORE_IDS",
+ [78] = "FUTEX_HASH",
};
static const char *prctl_set_mm_options[] = {
[1] = "START_CODE",
$
That now will be used to decode the syscall option and also to compose
filters, for instance:
[root@five ~]# perf trace -e syscalls:sys_enter_prctl --filter option==SET_NAME
0.000 Isolated Servi/3474327 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23f13b7aee)
0.032 DOM Worker/3474327 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23deb25670)
7.920 :3474328/3474328 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23e24fbb10)
7.935 StreamT~s #374/3474328 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23e24fb970)
8.400 Isolated Servi/3474329 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23e24bab10)
8.418 StreamT~s #374/3474329 syscalls:sys_enter_prctl(option: SET_NAME, arg2: 0x7f23e24ba970)
^C[root@five ~]#
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/prctl.h include/uapi/linux/prctl.h
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: James Clark <james.clark@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/trace/beauty/include/uapi/linux/prctl.h | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/tools/perf/trace/beauty/include/uapi/linux/prctl.h b/tools/perf/trace/beauty/include/uapi/linux/prctl.h
index 15c18ef4eb11a013..43dec6eed559a686 100644
--- a/tools/perf/trace/beauty/include/uapi/linux/prctl.h
+++ b/tools/perf/trace/beauty/include/uapi/linux/prctl.h
@@ -364,4 +364,11 @@ struct prctl_mm_map {
# define PR_TIMER_CREATE_RESTORE_IDS_ON 1
# define PR_TIMER_CREATE_RESTORE_IDS_GET 2
+/* FUTEX hash management */
+#define PR_FUTEX_HASH 78
+# define PR_FUTEX_HASH_SET_SLOTS 1
+# define FH_FLAG_IMMUTABLE (1ULL << 0)
+# define PR_FUTEX_HASH_GET_SLOTS 2
+# define PR_FUTEX_HASH_GET_IMMUTABLE 3
+
#endif /* _LINUX_PRCTL_H */
--
2.49.0