perf symbols: Fix symbols searching for module in buildid-cache

[karo-tx-linux.git] / tools / perf / util / build-id.c

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index b28100ee1732a5b4fd8c5ee8db327fb54f5b167b..f1479eeef7daf9ae2c386abcef7d079a0370c836 100644 (file)
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -166,6 +166,50 @@ char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
        return build_id__filename(build_id_hex, bf, size);
 }
 
+bool dso__build_id_is_kmod(const struct dso *dso, char *bf, size_t size)
+{
+       char *id_name, *ch;
+       struct stat sb;
+
+       id_name = dso__build_id_filename(dso, bf, size);
+       if (!id_name)
+               goto err;
+       if (access(id_name, F_OK))
+               goto err;
+       if (lstat(id_name, &sb) == -1)
+               goto err;
+       if ((size_t)sb.st_size > size - 1)
+               goto err;
+       if (readlink(id_name, bf, size - 1) < 0)
+               goto err;
+
+       bf[sb.st_size] = '\0';
+
+       /*
+        * link should be:
+        * ../../lib/modules/4.4.0-rc4/kernel/net/ipv4/netfilter/nf_nat_ipv4.ko/a09fe3eb3147dafa4e3b31dbd6257e4d696bdc92
+        */
+       ch = strrchr(bf, '/');
+       if (!ch)
+               goto err;
+       if (ch - 3 < bf)
+               goto err;
+
+       return strncmp(".ko", ch - 3, 3) == 0;
+err:
+       /*
+        * If dso__build_id_filename work, get id_name again,
+        * because id_name points to bf and is broken.
+        */
+       if (id_name)
+               id_name = dso__build_id_filename(dso, bf, size);
+       pr_err("Invalid build id: %s\n", id_name ? :
+                                        dso->long_name ? :
+                                        dso->short_name ? :
+                                        "[unknown]");
+       return false;
+}
+
 #define dsos__for_each_with_build_id(pos, head)        \
        list_for_each_entry(pos, head, node)    \
                if (!pos->has_build_id)         \