perf maps: Add functions to access maps

Introduce functions to access struct maps. These functions reduce the
number of places reference counting is necessary. While tidying APIs do
some small const-ification, in particlar to unwind_libunwind_ops.

Committer notes:

Fixed up tools/perf/util/unwind-libunwind.c:

-               return ops->get_entries(cb, arg, thread, data, max_stack);
+               return ops->get_entries(cb, arg, thread, data, max_stack, best_effort);

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, 19 insertions, 12 deletions

diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
index 509c287ee762..42528ade513e 100644
--- a/tools/perf/util/unwind-libunwind.c
+++ b/tools/perf/util/unwind-libunwind.c
@@ -22,12 +22,13 @@ int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized
 	const char *arch;
 	enum dso_type dso_type;
 	struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
+	struct machine *machine;
 	int err;
 
 	if (!dwarf_callchain_users)
 		return 0;
 
-	if (maps->addr_space) {
+	if (maps__addr_space(maps)) {
 		pr_debug("unwind: thread map already set, dso=%s\n",
 			 map->dso->name);
 		if (initialized)
@@ -35,15 +36,16 @@ int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized
 		return 0;
 	}
 
+	machine = maps__machine(maps);
 	/* env->arch is NULL for live-mode (i.e. perf top) */
-	if (!maps->machine->env || !maps->machine->env->arch)
+	if (!machine->env || !machine->env->arch)
 		goto out_register;
 
-	dso_type = dso__type(map->dso, maps->machine);
+	dso_type = dso__type(map->dso, machine);
 	if (dso_type == DSO__TYPE_UNKNOWN)
 		return 0;
 
-	arch = perf_env__arch(maps->machine->env);
+	arch = perf_env__arch(machine->env);
 
 	if (!strcmp(arch, "x86")) {
 		if (dso_type != DSO__TYPE_64BIT)
@@ -60,7 +62,7 @@ int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized
 out_register:
 	unwind__register_ops(maps, ops);
 
-	err = maps->unwind_libunwind_ops->prepare_access(maps);
+	err = maps__unwind_libunwind_ops(maps)->prepare_access(maps);
 	if (initialized)
 		*initialized = err ? false : true;
 	return err;
@@ -68,14 +70,18 @@ out_register:
 
 void unwind__flush_access(struct maps *maps)
 {
-	if (maps->unwind_libunwind_ops)
-		maps->unwind_libunwind_ops->flush_access(maps);
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
+
+	if (ops)
+		ops->flush_access(maps);
 }
 
 void unwind__finish_access(struct maps *maps)
 {
-	if (maps->unwind_libunwind_ops)
-		maps->unwind_libunwind_ops->finish_access(maps);
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
+
+	if (ops)
+		ops->finish_access(maps);
 }
 
 int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
@@ -83,8 +89,9 @@ int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
 			 struct perf_sample *data, int max_stack,
 			 bool best_effort)
 {
-	if (thread->maps->unwind_libunwind_ops)
-		return thread->maps->unwind_libunwind_ops->get_entries(cb, arg, thread, data,
-								       max_stack, best_effort);
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(thread->maps);
+
+	if (ops)
+		return ops->get_entries(cb, arg, thread, data, max_stack, best_effort);
 	return 0;
 }