perf buildid-cache: Check relocation when checking for existing kcore

[~andy/linux] / tools / perf / builtin-buildid-cache.c

diff --git a/tools/perf/builtin-buildid-cache.c b/tools/perf/builtin-buildid-cache.c
index cfede86161d8ae9410c123745bb60def09785331..b22dbb16f8776112f335e9185740a85645f2cf86 100644 (file)
--- a/tools/perf/builtin-buildid-cache.c
+++ b/tools/perf/builtin-buildid-cache.c
@@ -63,11 +63,35 @@ static int build_id_cache__kcore_dir(char *dir, size_t sz)
        return 0;
 }
 
+static bool same_kallsyms_reloc(const char *from_dir, char *to_dir)
+{
+       char from[PATH_MAX];
+       char to[PATH_MAX];
+       const char *name;
+       u64 addr1 = 0, addr2 = 0;
+       int i;
+
+       scnprintf(from, sizeof(from), "%s/kallsyms", from_dir);
+       scnprintf(to, sizeof(to), "%s/kallsyms", to_dir);
+
+       for (i = 0; (name = ref_reloc_sym_names[i]) != NULL; i++) {
+               addr1 = kallsyms__get_function_start(from, name);
+               if (addr1)
+                       break;
+       }
+
+       if (name)
+               addr2 = kallsyms__get_function_start(to, name);
+
+       return addr1 == addr2;
+}
+
 static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
                                          size_t to_dir_sz)
 {
        char from[PATH_MAX];
        char to[PATH_MAX];
+       char to_subdir[PATH_MAX];
        struct dirent *dent;
        int ret = -1;
        DIR *d;
@@ -86,10 +110,11 @@ static int build_id_cache__kcore_existing(const char *from_dir, char *to_dir,
                        continue;
                scnprintf(to, sizeof(to), "%s/%s/modules", to_dir,
                          dent->d_name);
-               if (!compare_proc_modules(from, to)) {
-                       scnprintf(to, sizeof(to), "%s/%s", to_dir,
-                                 dent->d_name);
-                       strlcpy(to_dir, to, to_dir_sz);
+               scnprintf(to_subdir, sizeof(to_subdir), "%s/%s",
+                         to_dir, dent->d_name);
+               if (!compare_proc_modules(from, to) &&
+                   same_kallsyms_reloc(from_dir, to_subdir)) {
+                       strlcpy(to_dir, to_subdir, to_dir_sz);
                        ret = 0;
                        break;
                }