perf map: Add accessor for dso

Later changes will add reference count checking for struct map, with
dso being the most frequently accessed variable. Add an accessor so
that the reference count check is only necessary in one place.

Additional changes:
 - add a dso variable to avoid repeated map__dso calls.
 - in builtin-mem.c dump_raw_samples, code only partially tested for
   dso == NULL. Make the possibility of NULL consistent.
 - in thread.c thread__memcpy fix use of spaces and use tabs.

Committer notes:

Did missing conversions on these files:

   tools/perf/arch/powerpc/util/skip-callchain-idx.c
   tools/perf/arch/powerpc/util/sym-handling.c
   tools/perf/ui/browsers/hists.c
   tools/perf/ui/gtk/annotate.c
   tools/perf/util/cs-etm.c
   tools/perf/util/thread.c
   tools/perf/util/unwind-libunwind-local.c
   tools/perf/util/unwind-libunwind.c

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 35 insertions, 20 deletions

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 316b63fb5691..a1c85c22676f 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -791,6 +791,7 @@ static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
 	*root = RB_ROOT_CACHED;
 
 	while (next) {
+		struct dso *curr_map_dso;
 		char *module;
 
 		pos = rb_entry(next, struct symbol, rb_node);
@@ -808,13 +809,13 @@ static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
 			symbol__delete(pos);
 			continue;
 		}
-
+		curr_map_dso = map__dso(curr_map);
 		pos->start -= curr_map->start - curr_map->pgoff;
 		if (pos->end > curr_map->end)
 			pos->end = curr_map->end;
 		if (pos->end)
 			pos->end -= curr_map->start - curr_map->pgoff;
-		symbols__insert(&curr_map->dso->symbols, pos);
+		symbols__insert(&curr_map_dso->symbols, pos);
 		++count;
 	}
 
@@ -856,12 +857,14 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 
 		module = strchr(pos->name, '\t');
 		if (module) {
+			struct dso *curr_map_dso;
+
 			if (!symbol_conf.use_modules)
 				goto discard_symbol;
 
 			*module++ = '\0';
-
-			if (strcmp(curr_map->dso->short_name, module)) {
+			curr_map_dso = map__dso(curr_map);
+			if (strcmp(curr_map_dso->short_name, module)) {
 				if (curr_map != initial_map &&
 				    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 				    machine__is_default_guest(machine)) {
@@ -872,7 +875,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 					 * symbols are in its kmap. Mark it as
 					 * loaded.
 					 */
-					dso__set_loaded(curr_map->dso);
+					dso__set_loaded(curr_map_dso);
 				}
 
 				curr_map = maps__find_by_name(kmaps, module);
@@ -884,8 +887,8 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 					curr_map = initial_map;
 					goto discard_symbol;
 				}
-
-				if (curr_map->dso->loaded &&
+				curr_map_dso = map__dso(curr_map);
+				if (curr_map_dso->loaded &&
 				    !machine__is_default_guest(machine))
 					goto discard_symbol;
 			}
@@ -954,8 +957,10 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 		}
 add_symbol:
 		if (curr_map != initial_map) {
+			struct dso *curr_map_dso = map__dso(curr_map);
+
 			rb_erase_cached(&pos->rb_node, root);
-			symbols__insert(&curr_map->dso->symbols, pos);
+			symbols__insert(&curr_map_dso->symbols, pos);
 			++moved;
 		} else
 			++count;
@@ -969,7 +974,7 @@ discard_symbol:
 	if (curr_map != initial_map &&
 	    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 	    machine__is_default_guest(maps__machine(kmaps))) {
-		dso__set_loaded(curr_map->dso);
+		dso__set_loaded(map__dso(curr_map));
 	}
 
 	return count + moved;
@@ -1143,13 +1148,14 @@ static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
 	maps__for_each_entry(kmaps, old_node) {
 		struct map *old_map = old_node->map;
 		struct module_info *mi;
+		struct dso *dso;
 
 		if (!__map__is_kmodule(old_map)) {
 			continue;
 		}
-
+		dso = map__dso(old_map);
 		/* Module must be in memory at the same address */
-		mi = find_module(old_map->dso->short_name, &modules);
+		mi = find_module(dso->short_name, &modules);
 		if (!mi || mi->start != old_map->start) {
 			err = -EINVAL;
 			goto out;
@@ -2047,14 +2053,17 @@ out:
 
 static int map__strcmp(const void *a, const void *b)
 {
-	const struct map *ma = *(const struct map **)a, *mb = *(const struct map **)b;
-	return strcmp(ma->dso->short_name, mb->dso->short_name);
+	const struct dso *dso_a = map__dso(*(const struct map **)a);
+	const struct dso *dso_b = map__dso(*(const struct map **)b);
+
+	return strcmp(dso_a->short_name, dso_b->short_name);
 }
 
 static int map__strcmp_name(const void *name, const void *b)
 {
-	const struct map *map = *(const struct map **)b;
-	return strcmp(name, map->dso->short_name);
+	const struct dso *dso = map__dso(*(const struct map **)b);
+
+	return strcmp(name, dso->short_name);
 }
 
 void __maps__sort_by_name(struct maps *maps)
@@ -2111,10 +2120,13 @@ struct map *maps__find_by_name(struct maps *maps, const char *name)
 
 	down_read(maps__lock(maps));
 
-	if (maps->last_search_by_name &&
-	    strcmp(maps->last_search_by_name->dso->short_name, name) == 0) {
-		map = maps->last_search_by_name;
-		goto out_unlock;
+	if (maps->last_search_by_name) {
+		const struct dso *dso = map__dso(maps->last_search_by_name);
+
+		if (strcmp(dso->short_name, name) == 0) {
+			map = maps->last_search_by_name;
+			goto out_unlock;
+		}
 	}
 	/*
 	 * If we have maps->maps_by_name, then the name isn't in the rbtree,
@@ -2127,8 +2139,11 @@ struct map *maps__find_by_name(struct maps *maps, const char *name)
 
 	/* Fallback to traversing the rbtree... */
 	maps__for_each_entry(maps, rb_node) {
+		struct dso *dso;
+
 		map = rb_node->map;
-		if (strcmp(map->dso->short_name, name) == 0) {
+		dso = map__dso(map);
+		if (strcmp(dso->short_name, name) == 0) {
 			maps->last_search_by_name = map;
 			goto out_unlock;
 		}