[PATCH perf/core 2/4] perf-probe: Add error checks to offline probe post-processing

[Masami Hiramatsu]

Add error check codes to post process and improve it for
offline probe events as;
 - post process fails if no matched symbol found in map(-ENOENT)
   or strdup() failed(-ENOMEM).
 - Even if the symbol name is same, it updates symbol address
   and offset.

Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
---
 tools/perf/util/probe-event.c |   50 +++++++++++++++++++++++++++--------------
 1 file changed, 33 insertions(+), 17 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 4a57c8a..aa8a922 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -610,6 +610,33 @@ static int find_perf_probe_point_from_dwarf(struct 
probe_trace_point *tp,
        return ret ? : -ENOENT;
 }
 
+/* Adjust symbol name and address */
+static int post_process_probe_trace_point(struct probe_trace_point *tp,
+                                          struct map *map, unsigned long offs)
+{
+       struct symbol *sym;
+       u64 addr = tp->address + tp->offset - offs;
+
+       sym = map__find_symbol(map, addr);
+       if (!sym)
+               return -ENOENT;
+
+       if (strcmp(sym->name, tp->symbol)) {
+               /* If we have no realname, use symbol for it */
+               if (!tp->realname)
+                       tp->realname = tp->symbol;
+               else
+                       free(tp->symbol);
+               tp->symbol = strdup(sym->name);
+               if (!tp->symbol)
+                       return -ENOMEM;
+       }
+       tp->offset = addr - sym->start;
+       tp->address -= offs;
+
+       return 0;
+}
+
 /*
  * Rename DWARF symbols to ELF symbols -- gcc sometimes optimizes functions
  * and generate new symbols with suffixes such as .constprop.N or .isra.N
@@ -622,11 +649,9 @@ static int
 post_process_offline_probe_trace_events(struct probe_trace_event *tevs,
                                        int ntevs, const char *pathname)
 {
-       struct symbol *sym;
        struct map *map;
        unsigned long stext = 0;
-       u64 addr;
-       int i;
+       int i, ret = 0;
 
        /* Prepare a map for offline binary */
        map = dso__new_map(pathname);
@@ -636,23 +661,14 @@ post_process_offline_probe_trace_events(struct 
probe_trace_event *tevs,
        }
 
        for (i = 0; i < ntevs; i++) {
-               addr = tevs[i].point.address + tevs[i].point.offset - stext;
-               sym = map__find_symbol(map, addr);
-               if (!sym)
-                       continue;
-               if (!strcmp(sym->name, tevs[i].point.symbol))
-                       continue;
-               /* If we have no realname, use symbol for it */
-               if (!tevs[i].point.realname)
-                       tevs[i].point.realname = tevs[i].point.symbol;
-               else
-                       free(tevs[i].point.symbol);
-               tevs[i].point.symbol = strdup(sym->name);
-               tevs[i].point.offset = addr - sym->start;
+               ret = post_process_probe_trace_point(&tevs[i].point,
+                                                    map, stext);
+               if (ret < 0)
+                       break;
        }
        map__put(map);
 
-       return 0;
+       return ret;
 }
 
 static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs,