perf tools: Complete support for dynamic strings

Complete support for __str_loc type strings of ftrace events
which have dynamic offsets values set for each of them inside
their sammples.

Before:
        geany-5759  [000]     0.000000: lock_release: name
        geany-5759  [000]     0.000000: lock_release: name
        geany-5759  [000]     0.000000: lock_release: name
  kondemand/0-362   [000]     0.000000: lock_release: name
      pdflush-421   [000]     0.000000: lock_release: name

After:
        geany-5759  [000]     0.000000: lock_release: &u->lock
        geany-5759  [000]     0.000000: lock_release: key
        geany-5759  [000]     0.000000: lock_release: &group->notification_mutex
  kondemand/0-362   [000]     0.000000: lock_release: &rq->lock
      pdflush-421   [000]     0.000000: lock_release: &rq->lock

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1251693921-6579-4-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 96c5e97..665dac2 100644 (file)
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -1548,6 +1548,7 @@ process_str(struct event *event __unused, struct print_arg *arg, char **tok)
 
        arg->type = PRINT_STRING;
        arg->string.string = token;
+       arg->string.offset = -1;
 
        if (read_expected(EVENT_DELIM, (char *)")") < 0)
                return EVENT_ERROR;
@@ -2031,9 +2032,20 @@ static void print_str_arg(void *data, int size,
 
        case PRINT_TYPE:
                break;
-       case PRINT_STRING:
-               printf("%s", arg->string.string);
+       case PRINT_STRING: {
+               int str_offset;
+
+               if (arg->string.offset == -1) {
+                       struct format_field *f;
+
+                       f = find_any_field(event, arg->string.string);
+                       arg->string.offset = f->offset;
+               }
+               str_offset = *(int *)(data + arg->string.offset);
+               str_offset &= 0xffff;
+               printf("%s", ((char *)data) + str_offset);
                break;
+       }
        case PRINT_OP:
                /*
                 * The only op for string should be ? :

diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h
index 051fcf3..420294a 100644 (file)
--- a/tools/perf/util/trace-event.h
+++ b/tools/perf/util/trace-event.h
@@ -50,6 +50,7 @@ struct print_arg_atom {
 
 struct print_arg_string {
        char                    *string;
+       int                     offset;
 };
 
 struct print_arg_field {