perf probe: Cleanup synthesize_probe_trace_command()

Cleanup synthesize_probe_trace_command() to simplify the code path.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/162282411361.452340.16886399333622147122.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 0fb6ab2..0412842 100644 (file)
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2127,19 +2127,55 @@ static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
 }
 
 static int
-synthesize_uprobe_trace_def(struct probe_trace_event *tev, struct strbuf *buf)
+synthesize_probe_trace_args(struct probe_trace_event *tev, struct strbuf *buf)
+{
+       int i, ret = 0;
+
+       for (i = 0; i < tev->nargs && ret >= 0; i++)
+               ret = synthesize_probe_trace_arg(&tev->args[i], buf);
+
+       return ret;
+}
+
+static int
+synthesize_uprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
 {
-       struct probe_trace_point *tp = &tev->point;
        int err;
 
+       /* Uprobes must have tp->module */
+       if (!tp->module)
+               return -EINVAL;
+       /*
+        * If tp->address == 0, then this point must be a
+        * absolute address uprobe.
+        * try_to_find_absolute_address() should have made
+        * tp->symbol to "0x0".
+        */
+       if (!tp->address && (!tp->symbol || strcmp(tp->symbol, "0x0")))
+               return -EINVAL;
+
+       /* Use the tp->address for uprobes */
        err = strbuf_addf(buf, "%s:0x%lx", tp->module, tp->address);
 
        if (err >= 0 && tp->ref_ctr_offset) {
                if (!uprobe_ref_ctr_is_supported())
-                       return -1;
+                       return -EINVAL;
                err = strbuf_addf(buf, "(0x%lx)", tp->ref_ctr_offset);
        }
-       return err >= 0 ? 0 : -1;
+       return err >= 0 ? 0 : err;
+}
+
+static int
+synthesize_kprobe_trace_def(struct probe_trace_point *tp, struct strbuf *buf)
+{
+       if (!strncmp(tp->symbol, "0x", 2)) {
+               /* Absolute address. See try_to_find_absolute_address() */
+               return strbuf_addf(buf, "%s%s0x%lx", tp->module ?: "",
+                                 tp->module ? ":" : "", tp->address);
+       } else {
+               return strbuf_addf(buf, "%s%s%s+%lu", tp->module ?: "",
+                               tp->module ? ":" : "", tp->symbol, tp->offset);
+       }
 }
 
 char *synthesize_probe_trace_command(struct probe_trace_event *tev)
@@ -2147,11 +2183,7 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
        struct probe_trace_point *tp = &tev->point;
        struct strbuf buf;
        char *ret = NULL;
-       int i, err;
-
-       /* Uprobes must have tp->module */
-       if (tev->uprobes && !tp->module)
-               return NULL;
+       int err;
 
        if (strbuf_init(&buf, 32) < 0)
                return NULL;
@@ -2159,37 +2191,17 @@ char *synthesize_probe_trace_command(struct probe_trace_event *tev)
        if (strbuf_addf(&buf, "%c:%s/%s ", tp->retprobe ? 'r' : 'p',
                        tev->group, tev->event) < 0)
                goto error;
-       /*
-        * If tp->address == 0, then this point must be a
-        * absolute address uprobe.
-        * try_to_find_absolute_address() should have made
-        * tp->symbol to "0x0".
-        */
-       if (tev->uprobes && !tp->address) {
-               if (!tp->symbol || strcmp(tp->symbol, "0x0"))
-                       goto error;
-       }
 
-       /* Use the tp->address for uprobes */
-       if (tev->uprobes) {
-               err = synthesize_uprobe_trace_def(tev, &buf);
-       } else if (!strncmp(tp->symbol, "0x", 2)) {
-               /* Absolute address. See try_to_find_absolute_address() */
-               err = strbuf_addf(&buf, "%s%s0x%lx", tp->module ?: "",
-                                 tp->module ? ":" : "", tp->address);
-       } else {
-               err = strbuf_addf(&buf, "%s%s%s+%lu", tp->module ?: "",
-                               tp->module ? ":" : "", tp->symbol, tp->offset);
-       }
-
-       if (err)
-               goto error;
+       if (tev->uprobes)
+               err = synthesize_uprobe_trace_def(tp, &buf);
+       else
+               err = synthesize_kprobe_trace_def(tp, &buf);
 
-       for (i = 0; i < tev->nargs; i++)
-               if (synthesize_probe_trace_arg(&tev->args[i], &buf) < 0)
-                       goto error;
+       if (err >= 0)
+               err = synthesize_probe_trace_args(tev, &buf);
 
-       ret = strbuf_detach(&buf, NULL);
+       if (err >= 0)
+               ret = strbuf_detach(&buf, NULL);
 error:
        strbuf_release(&buf);
        return ret;