linux-imx

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>