[PATCH 5/9] perf probe: Finder fails to resolve function name to address

From: Arnaldo Carvalho de Melo
Date: Fri Mar 30 2012 - 12:11:13 EST

From: Prashanth Nageshappa <prashanth@xxxxxxxxxxxxxxxxxx>

If DIE entries corresponding to declarations appear before definition
entry, probe finder returns error instead of continuing to look further
for a definition entry.

This patch ensures we reach to the DIE entry corresponding to the
definition and get the function address.

V2: A simpler solution based on Masami's suggestion.

Signed-off-by: Prashanth Nageshappa <prashanth@xxxxxxxxxxxxxxxxxx>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Cc: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Link: http://lkml.kernel.org/r/4F703FB9.9020407@xxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
tools/perf/util/probe-finder.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 2cc162d..d448984 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -972,10 +972,12 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
struct dwarf_callback_param *param = data;
struct probe_finder *pf = param->data;
struct perf_probe_point *pp = &pf->pev->point;
+ Dwarf_Attribute attr;

/* Check tag and diename */
if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
- !die_compare_name(sp_die, pp->function))
+ !die_compare_name(sp_die, pp->function) ||
+ dwarf_attr(sp_die, DW_AT_declaration, &attr))
return DWARF_CB_OK;

/* Check declared file */

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