perf trace beauty: Allow accessing syscall args values in a syscall arg formatter

For instance, fcntl's upcoming 'arg' formatter needs to look at the
'cmd' value to decide how to format its value, sometimes it is a file
flags, sometimes an fd, a pointer to a structure, etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
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: http://lkml.kernel.org/n/tip-2tw2jfaqm48dtw8a4addghze@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/tools/perf/trace/beauty/beauty.h b/tools/perf/trace/beauty/beauty.h
index ce01079d8422..6fbac0c8120d 100644
--- a/tools/perf/trace/beauty/beauty.h
+++ b/tools/perf/trace/beauty/beauty.h
@@ -6,8 +6,19 @@
 struct trace;
 struct thread;
 
+/**
+ * @val: value of syscall argument being formatted
+ * @args: All the args, use syscall_args__val(arg, nth) to access one
+ * @thread: tid state (maps, pid, tid, etc)
+ * @trace: 'perf trace' internals: all threads, etc
+ * @parm: private area, may be an strarray, for instance
+ * @idx: syscall arg idx (is this the first?)
+ * @mask: a syscall arg may mask another arg, see syscall_arg__scnprintf_futex_op
+ */
+
 struct syscall_arg {
 	unsigned long val;
+	unsigned char *args;
 	struct thread *thread;
 	struct trace  *trace;
 	void	      *parm;
@@ -15,6 +26,8 @@ struct syscall_arg {
 	u8	      mask;
 };
 
+unsigned long syscall_arg__val(struct syscall_arg *arg, u8 idx);
+
 size_t syscall_arg__scnprintf_strarrays(char *bf, size_t size, struct syscall_arg *arg);
 #define SCA_STRARRAYS syscall_arg__scnprintf_strarrays