tjh.dev
perf trace: Beautify 'fspick' arguments
Use existing beautifiers for the first 2 args (dfd, path) and wire up
the recently introduced fspick flags table generator.
Now it should be possible to just use:
perf trace -e fspick
As root and see all move_mount syscalls with its args beautified, either
using the vfs_getname perf probe method or using the
augmented_raw_syscalls.c eBPF helper to get the pathnames, the other
args should work in all cases, i.e. all that is needed can be obtained
directly from the raw_syscalls:sys_enter tracepoint args.
# cat sys_fspick.c
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <unistd.h>
#include <sys/syscall.h> /* For SYS_xxx definitions */
#include <fcntl.h>
#define __NR_fspick 433
#define FSPICK_CLOEXEC 0x00000001
#define FSPICK_SYMLINK_NOFOLLOW 0x00000002
#define FSPICK_NO_AUTOMOUNT 0x00000004
#define FSPICK_EMPTY_PATH 0x00000008
static inline int sys_fspick(int fd, const char *path, int flags)
{
syscall(__NR_fspick, fd, path, flags);
}
int main(int argc, char *argv[])
{
int flags = 0, fd = 0;
open("/foo", 0);
sys_fspick(fd++, "/foo1", flags);
flags |= FSPICK_CLOEXEC;
sys_fspick(fd++, "/foo2", flags);
flags |= FSPICK_SYMLINK_NOFOLLOW;
sys_fspick(fd++, "/foo3", flags);
flags |= FSPICK_NO_AUTOMOUNT;
sys_fspick(fd++, "/foo4", flags);
flags |= FSPICK_EMPTY_PATH;
return sys_fspick(fd++, "/foo5", flags);
}
# perf trace -e fspick ./sys_fspick
LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o
fspick(0, "/foo1", 0) = -1 ENOENT (No such file or directory)
fspick(1, "/foo2", FSPICK_CLOEXEC) = -1 ENOENT (No such file or directory)
fspick(2, "/foo3", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW) = -1 ENOENT (No such file or directory)
fspick(3, "/foo4", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW|FSPICK_NO_AUTOMOUNT) = -1 ENOENT (No such file or directory)
fspick(4, "/foo5", FSPICK_CLOEXEC|FSPICK_SYMLINK_NOFOLLOW|FSPICK_NO_AUTOMOUNT|FSPICK_EMPTY_PATH) = -1 ENOENT (No such file or directory)
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-erau5xjtt8wvgnhvdbchstuk@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>