To pick a new prctl introduced in:
1446e1df9eb183fd ("kernel: Implement selective syscall userspace redirection")
That results in:
$ tools/perf/trace/beauty/prctl_option.sh > before
$ cp include/uapi/linux/prctl.h tools/include/uapi/linux/prctl.h
$ tools/perf/trace/beauty/prctl_option.sh > after
$ diff -u before after
--- before 2020-12-17 15:00:42.
012537367 -0300
+++ after 2020-12-17 15:00:49.
832699463 -0300
@@ -53,6 +53,7 @@
[56] = "GET_TAGGED_ADDR_CTRL",
[57] = "SET_IO_FLUSHER",
[58] = "GET_IO_FLUSHER",
+ [59] = "SET_SYSCALL_USER_DISPATCH",
};
static const char *prctl_set_mm_options[] = {
[1] = "START_CODE",
$
Now users can do:
# perf trace -e syscalls:sys_enter_prctl --filter "option==SET_SYSCALL_USER_DISPATCH"
^C#
# trace -v -e syscalls:sys_enter_prctl --filter "option==SET_SYSCALL_USER_DISPATCH"
New filter for syscalls:sys_enter_prctl: (option==0x3b) && (common_pid != 5519 && common_pid != 3404)
^C#
And also when prctl appears in a session, its options will be
translated to the string.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
#define PR_SET_IO_FLUSHER 57
#define PR_GET_IO_FLUSHER 58
+/* Dispatch syscalls to a userspace handler */
+#define PR_SET_SYSCALL_USER_DISPATCH 59
+# define PR_SYS_DISPATCH_OFF 0
+# define PR_SYS_DISPATCH_ON 1
+
#endif /* _LINUX_PRCTL_H */