[PATCH v1 11/11] perf tools: Scope mount namespace entry in dso__load()

[Namhyung Kim <namhyung@kernel.org>]

Enter the target mount namespace only for the specific binary types
that need it.

Assisted-by: LLM
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/symbol.c | 43 +++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 807e433c770812a4..063e9da0878e93bc 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1811,17 +1811,6 @@ int dso__load(struct dso *dso, struct map *map)
 	const char *map_path = dso__long_name(dso);
 
 	mutex_lock(dso__lock(dso));
-	perfmap = is_perf_pid_map_name(map_path);
-
-	if (perfmap) {
-		if (dso__nsinfo(dso) &&
-		    (dso__find_perf_map(newmapname, sizeof(newmapname),
-					dso__nsinfo_ptr(dso)) == 0)) {
-			map_path = newmapname;
-		}
-	}
-
-	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
 
 	/* check again under the dso->lock */
 	if (dso__loaded(dso)) {
@@ -1845,8 +1834,16 @@ int dso__load(struct dso *dso, struct map *map)
 
 	dso__set_adjust_symbols(dso, false);
 
+	perfmap = is_perf_pid_map_name(map_path);
 	if (perfmap) {
+		if (dso__nsinfo(dso) &&
+		    (dso__find_perf_map(newmapname, sizeof(newmapname),
+					dso__nsinfo_ptr(dso)) == 0)) {
+			map_path = newmapname;
+		}
+		nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
 		ret = dso__load_perf_map(map_path, dso);
+		nsinfo__mountns_exit(&nsc);
 		dso__set_binary_type(dso, DSO_BINARY_TYPE__JAVA_JIT);
 		dso__set_symtab_type(dso, ret > 0
 				? DSO_BINARY_TYPE__JAVA_JIT
@@ -1869,7 +1866,7 @@ int dso__load(struct dso *dso, struct map *map)
 		struct build_id bid = { .size = 0, };
 
 		__symbol__join_symfs(name, PATH_MAX, dso__long_name(dso));
-		if (filename__read_build_id(name, &bid) > 0)
+		if (filename__read_build_id_ns(name, &bid, dso__nsinfo(dso)) > 0)
 			dso__set_build_id(dso, &bid);
 	}
 
@@ -1882,24 +1879,25 @@ int dso__load(struct dso *dso, struct map *map)
 		struct symsrc *ss = &ss_[ss_pos];
 		bool next_slot = false;
 		bool is_reg;
-		bool nsexit;
+		bool nsenter;
 		int bfdrc = -1;
 		int sirc = -1;
 
 		enum dso_binary_type symtab_type = binary_type_symtab[i];
 
-		nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
-		    symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
-
 		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
 			continue;
 
+		nsenter = dso_binary_type__needs_ns(symtab_type);
+		if (nsenter)
+			nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
+
 		if (dso__read_binary_type_filename(dso, symtab_type,
-						   root_dir, name, PATH_MAX))
+						   root_dir, name, PATH_MAX)) {
+			if (nsenter)
+				nsinfo__mountns_exit(&nsc);
 			continue;
-
-		if (nsexit)
-			nsinfo__mountns_exit(&nsc);
+		}
 
 		is_reg = is_regular_file(name);
 
@@ -1910,8 +1908,8 @@ int dso__load(struct dso *dso, struct map *map)
 		if (is_reg && bfdrc < 0)
 			sirc = symsrc__init(ss, dso, name, symtab_type);
 
-		if (nsexit)
-			nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
+		if (nsenter)
+			nsinfo__mountns_exit(&nsc);
 
 		if (bfdrc > 0) {
 			dso__set_symtab_type(dso, symtab_type);
@@ -1978,7 +1976,6 @@ int dso__load(struct dso *dso, struct map *map)
 out:
 	dso__set_loaded(dso);
 	mutex_unlock(dso__lock(dso));
-	nsinfo__mountns_exit(&nsc);
 
 	return ret;
 }
-- 
2.56.0.257.gf7497c7d27-goog