perf probe: Fix to handle optimized not-inlined functions

Fix to handle optimized no-inline functions which have only function
definition but no actual instance at that point.

To fix this problem, we need to find actual instance of the function.

Without this patch:
  ----
  # perf probe -a __up
  Failed to get entry address of __up.
    Error: Failed to add events.
  # perf probe -L __up
  Specified source line is not found.
    Error: Failed to show lines.
  ----

With this patch:
  ----
  # perf probe -a __up
  Added new event:
    probe:__up           (on __up)

  You can now use it in all perf tools, such as:

          perf record -e probe:__up -aR sleep 1

  # perf probe -L __up
  <__up@/home/fedora/ksrc/linux-3/kernel/locking/semaphore.c:0>
        0  static noinline void __sched __up(struct semaphore *sem)
           {
                  struct semaphore_waiter *waiter = list_first_entry(&sem->wait_
                                                          struct semaphore_waite
        4         list_del(&waiter->list);
        5         waiter->up = true;
        6         wake_up_process(waiter->task);
        7  }
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150130093744.30575.43290.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 4 insertions, 8 deletions

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index b5247d777f0e..d14193518e4d 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -915,17 +915,13 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
 		dwarf_decl_line(sp_die, &pf->lno);
 		pf->lno += pp->line;
 		param->retval = find_probe_point_by_line(pf);
-	} else if (!dwarf_func_inline(sp_die)) {
+	} else if (die_is_func_instance(sp_die)) {
+		/* Instances always have the entry address */
+		dwarf_entrypc(sp_die, &pf->addr);
 		/* Real function */
 		if (pp->lazy_line)
 			param->retval = find_probe_point_lazy(sp_die, pf);
 		else {
-			if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
-				pr_warning("Failed to get entry address of "
-					   "%s.\n", dwarf_diename(sp_die));
-				param->retval = -ENOENT;
-				return DWARF_CB_ABORT;
-			}
 			pf->addr += pp->offset;
 			/* TODO: Check the address in this function */
 			param->retval = call_probe_finder(sp_die, pf);
@@ -1536,7 +1532,7 @@ static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
 		pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
 		lr->start = lf->lno_s;
 		lr->end = lf->lno_e;
-		if (dwarf_func_inline(sp_die))
+		if (!die_is_func_instance(sp_die))
 			param->retval = die_walk_instances(sp_die,
 						line_range_inline_cb, lf);
 		else