Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/perf/util/unwind.h b/tools/perf/util/unwind.h
index 8a44a15..3a7d00c 100644
--- a/tools/perf/util/unwind.h
+++ b/tools/perf/util/unwind.h
@@ -6,6 +6,7 @@
 #include <linux/types.h>
 
 struct map;
+struct map_groups;
 struct perf_sample;
 struct symbol;
 struct thread;
@@ -19,9 +20,9 @@
 typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg);
 
 struct unwind_libunwind_ops {
-	int (*prepare_access)(struct thread *thread);
-	void (*flush_access)(struct thread *thread);
-	void (*finish_access)(struct thread *thread);
+	int (*prepare_access)(struct map_groups *mg);
+	void (*flush_access)(struct map_groups *mg);
+	void (*finish_access)(struct map_groups *mg);
 	int (*get_entries)(unwind_entry_cb_t cb, void *arg,
 			   struct thread *thread,
 			   struct perf_sample *data, int max_stack);
@@ -46,20 +47,20 @@
 #endif
 
 int LIBUNWIND__ARCH_REG_ID(int regnum);
-int unwind__prepare_access(struct thread *thread, struct map *map,
+int unwind__prepare_access(struct map_groups *mg, struct map *map,
 			   bool *initialized);
-void unwind__flush_access(struct thread *thread);
-void unwind__finish_access(struct thread *thread);
+void unwind__flush_access(struct map_groups *mg);
+void unwind__finish_access(struct map_groups *mg);
 #else
-static inline int unwind__prepare_access(struct thread *thread __maybe_unused,
+static inline int unwind__prepare_access(struct map_groups *mg __maybe_unused,
 					 struct map *map __maybe_unused,
 					 bool *initialized __maybe_unused)
 {
 	return 0;
 }
 
-static inline void unwind__flush_access(struct thread *thread __maybe_unused) {}
-static inline void unwind__finish_access(struct thread *thread __maybe_unused) {}
+static inline void unwind__flush_access(struct map_groups *mg __maybe_unused) {}
+static inline void unwind__finish_access(struct map_groups *mg __maybe_unused) {}
 #endif
 #else
 static inline int
@@ -72,14 +73,14 @@
 	return 0;
 }
 
-static inline int unwind__prepare_access(struct thread *thread __maybe_unused,
+static inline int unwind__prepare_access(struct map_groups *mg __maybe_unused,
 					 struct map *map __maybe_unused,
 					 bool *initialized __maybe_unused)
 {
 	return 0;
 }
 
-static inline void unwind__flush_access(struct thread *thread __maybe_unused) {}
-static inline void unwind__finish_access(struct thread *thread __maybe_unused) {}
+static inline void unwind__flush_access(struct map_groups *mg __maybe_unused) {}
+static inline void unwind__finish_access(struct map_groups *mg __maybe_unused) {}
 #endif /* HAVE_DWARF_UNWIND_SUPPORT */
 #endif /* __UNWIND_H */