perf maps: Remove rb_node from struct map

struct map is reference counted, having it also be a node in an
red-black tree complicates the reference counting. Switch to having a
map_rb_node which is a red-block tree node but points at the reference
counted struct map. This reference is responsible for a single reference
count.

Committer notes:

Fixed up tools/perf/util/unwind-libunwind-local.c to use map_rb_node as
well.

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, 11 insertions, 7 deletions

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 881d94f65a6b..cdf5d655d84c 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -151,23 +151,27 @@ static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
 static struct map *kernel_get_module_map(const char *module)
 {
 	struct maps *maps = machine__kernel_maps(host_machine);
-	struct map *pos;
+	struct map_rb_node *pos;
 
 	/* A file path -- this is an offline module */
 	if (module && strchr(module, '/'))
 		return dso__new_map(module);
 
 	if (!module) {
-		pos = machine__kernel_map(host_machine);
-		return map__get(pos);
+		struct map *map = machine__kernel_map(host_machine);
+
+		return map__get(map);
 	}
 
 	maps__for_each_entry(maps, pos) {
 		/* short_name is "[module]" */
-		if (strncmp(pos->dso->short_name + 1, module,
-			    pos->dso->short_name_len - 2) == 0 &&
-		    module[pos->dso->short_name_len - 2] == '\0') {
-			return map__get(pos);
+		const char *short_name = pos->map->dso->short_name;
+		u16 short_name_len =  pos->map->dso->short_name_len;
+
+		if (strncmp(short_name + 1, module,
+			    short_name_len - 2) == 0 &&
+		    module[short_name_len - 2] == '\0') {
+			return map__get(pos->map);
 		}
 	}
 	return NULL;