[tip:perf/urgent] perf trace: Beautify the umount's 'name' argument

[tip:perf/urgent] perf trace: Beautify the umount's 'name' argument

[tip-bot for Arnaldo Carvalho de Melo]

Commit-ID:  476c92cacf383c83584ba02d06c88cf18f062afb
Gitweb:     https://git.kernel.org/tip/476c92cacf383c83584ba02d06c88cf18f062afb
Author:     Arnaldo Carvalho de Melo <acme@redhat.com>
AuthorDate: Fri, 26 Oct 2018 13:23:25 -0300
Committer:  Arnaldo Carvalho de Melo <acme@redhat.com>
CommitDate: Tue, 30 Oct 2018 11:46:23 -0300

perf trace: Beautify the umount's 'name' argument

By using the SCA_FILENAME beautifier, that works when either the
probe:vfs_getname probe is in place or with the eBPF program
tools/perf/examples/bpf/augmented_syscalls.c:

  # perf probe -l
  probe:vfs_getname (on getname_flags:73@acme/git/linux/fs/namei.c with pathname)
  # perf trace -e umount
  9630.332 ( 9.521 ms): umount/8082 umount2(name: /mnt) = 0
  #

The augmented syscalls one will be done in the next patch.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Benjamin Peterson <benjamin@python.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-hegbzlpd2nrn584l5jxn7sy2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-trace.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index db8711061ca3..d286f73ef2e5 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -838,7 +838,8 @@ static struct syscall_fmt {
 	  .arg = { [2] = { .scnprintf = SCA_SIGNUM, /* sig */ }, }, },
 	{ .name	    = "tkill",
 	  .arg = { [1] = { .scnprintf = SCA_SIGNUM, /* sig */ }, }, },
-	{ .name     = "umount2", .alias = "umount", },
+	{ .name     = "umount2", .alias = "umount",
+	  .arg = { [0] = { .scnprintf = SCA_FILENAME, /* name */ }, }, },
 	{ .name	    = "uname", .alias = "newuname", },
 	{ .name	    = "unlinkat",
 	  .arg = { [0] = { .scnprintf = SCA_FDAT, /* dfd */ }, }, },