perf symbols: Destroy unused symsrcs

[~andy/linux] / tools / perf / util / symbol.c

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 39ce9adbaaf0bef120e0903e72ad1e98f8114527..e89afc097d8ad2d4b818f07e02321084110e6ddc 100644 (file)
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -627,7 +627,7 @@ static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
  * kernel range is broken in several maps, named [kernel].N, as we don't have
  * the original ELF section names vmlinux have.
  */
-static int dso__split_kallsyms(struct dso *dso, struct map *map,
+static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
                               symbol_filter_t filter)
 {
        struct map_groups *kmaps = map__kmap(map)->kmaps;
@@ -692,6 +692,12 @@ static int dso__split_kallsyms(struct dso *dso, struct map *map,
                        char dso_name[PATH_MAX];
                        struct dso *ndso;
 
+                       if (delta) {
+                               /* Kernel was relocated at boot time */
+                               pos->start -= delta;
+                               pos->end -= delta;
+                       }
+
                        if (count == 0) {
                                curr_map = map;
                                goto filter_symbol;
@@ -721,6 +727,10 @@ static int dso__split_kallsyms(struct dso *dso, struct map *map,
                        curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
                        map_groups__insert(kmaps, curr_map);
                        ++kernel_range;
+               } else if (delta) {
+                       /* Kernel was relocated at boot time */
+                       pos->start -= delta;
+                       pos->end -= delta;
                }
 filter_symbol:
                if (filter && filter(curr_map, pos)) {
@@ -976,6 +986,23 @@ static int validate_kcore_modules(const char *kallsyms_filename,
        return 0;
 }
 
+static int validate_kcore_addresses(const char *kallsyms_filename,
+                                   struct map *map)
+{
+       struct kmap *kmap = map__kmap(map);
+
+       if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
+               u64 start;
+
+               start = kallsyms__get_function_start(kallsyms_filename,
+                                                    kmap->ref_reloc_sym->name);
+               if (start != kmap->ref_reloc_sym->addr)
+                       return -EINVAL;
+       }
+
+       return validate_kcore_modules(kallsyms_filename, map);
+}
+
 struct kcore_mapfn_data {
        struct dso *dso;
        enum map_type type;
@@ -1019,8 +1046,8 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
                                             kallsyms_filename))
                return -EINVAL;
 
-       /* All modules must be present at their original addresses */
-       if (validate_kcore_modules(kallsyms_filename, map))
+       /* Modules and kernel must be present at their original addresses */
+       if (validate_kcore_addresses(kallsyms_filename, map))
                return -EINVAL;
 
        md.dso = dso;
@@ -1113,15 +1140,41 @@ out_err:
        return -EINVAL;
 }
 
+/*
+ * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
+ * delta based on the relocation reference symbol.
+ */
+static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
+{
+       struct kmap *kmap = map__kmap(map);
+       u64 addr;
+
+       if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
+               return 0;
+
+       addr = kallsyms__get_function_start(filename,
+                                           kmap->ref_reloc_sym->name);
+       if (!addr)
+               return -1;
+
+       *delta = addr - kmap->ref_reloc_sym->addr;
+       return 0;
+}
+
 int dso__load_kallsyms(struct dso *dso, const char *filename,
                       struct map *map, symbol_filter_t filter)
 {
+       u64 delta = 0;
+
        if (symbol__restricted_filename(filename, "/proc/kallsyms"))
                return -1;
 
        if (dso__load_all_kallsyms(dso, filename, map) < 0)
                return -1;
 
+       if (kallsyms__delta(map, filename, &delta))
+               return -1;
+
        symbols__fixup_duplicate(&dso->symbols[map->type]);
        symbols__fixup_end(&dso->symbols[map->type]);
 
@@ -1133,7 +1186,7 @@ int dso__load_kallsyms(struct dso *dso, const char *filename,
        if (!dso__load_kcore(dso, map, filename))
                return dso__split_kallsyms_for_kcore(dso, map, filter);
        else
-               return dso__split_kallsyms(dso, map, filter);
+               return dso__split_kallsyms(dso, map, delta, filter);
 }
 
 static int dso__load_perf_map(struct dso *dso, struct map *map,
@@ -1283,6 +1336,8 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
 
                        if (syms_ss && runtime_ss)
                                break;
+               } else {
+                       symsrc__destroy(ss);
                }
 
        }
@@ -1424,7 +1479,7 @@ static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
                        continue;
                scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
                          "%s/%s/kallsyms", dir, dent->d_name);
-               if (!validate_kcore_modules(kallsyms_filename, map)) {
+               if (!validate_kcore_addresses(kallsyms_filename, map)) {
                        strlcpy(dir, kallsyms_filename, dir_sz);
                        ret = 0;
                        break;
@@ -1479,7 +1534,7 @@ static char *dso__find_kallsyms(struct dso *dso, struct map *map)
                if (fd != -1) {
                        close(fd);
                        /* If module maps match go with /proc/kallsyms */
-                       if (!validate_kcore_modules("/proc/kallsyms", map))
+                       if (!validate_kcore_addresses("/proc/kallsyms", map))
                                goto proc_kallsyms;
                }