[tip:locking/core] sched/completions: Add support for initializing completions with lockdep_map

[tip-bot for Byungchul Park]

Commit-ID:  a7967bc31584bd282682981295861e7bcba19e65
Gitweb:     https://git.kernel.org/tip/a7967bc31584bd282682981295861e7bcba19e65
Author:     Byungchul Park <byungchul.park@xxxxxxx>
AuthorDate: Wed, 25 Oct 2017 17:56:03 +0900
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 25 Oct 2017 12:19:03 +0200

sched/completions: Add support for initializing completions with lockdep_map

Sometimes we want to initialize completions with sparate lockdep maps
to assign lock classes as desired. For example, the workqueue code
needs to directly manage lockdep maps, since only the code is aware of
how to classify lockdep maps properly.

Provide additional macros initializing completions in that way.

Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: amir73il@xxxxxxxxx
Cc: axboe@xxxxxxxxx
Cc: darrick.wong@xxxxxxxxxx
Cc: david@xxxxxxxxxxxxx
Cc: hch@xxxxxxxxxxxxx
Cc: idryomov@xxxxxxxxx
Cc: johan@xxxxxxxxxx
Cc: johannes.berg@xxxxxxxxx
Cc: kernel-team@xxxxxxx
Cc: linux-block@xxxxxxxxxxxxxxx
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: linux-xfs@xxxxxxxxxxxxxxx
Cc: oleg@xxxxxxxxxx
Cc: tj@xxxxxxxxxx
Link: http://lkml.kernel.org/r/1508921765-15396-8-git-send-email-byungchul.park@xxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 include/linux/completion.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/include/linux/completion.h b/include/linux/completion.h
index 9121803..4da4991 100644
--- a/include/linux/completion.h
+++ b/include/linux/completion.h
@@ -49,6 +49,13 @@ static inline void complete_release_commit(struct completion *x)
 	lock_commit_crosslock((struct lockdep_map *)&x->map);
 }
 
+#define init_completion_map(x, m)					\
+do {									\
+	lockdep_init_map_crosslock((struct lockdep_map *)&(x)->map,	\
+			(m)->name, (m)->key, 0);				\
+	__init_completion(x);						\
+} while (0)
+
 #define init_completion(x)						\
 do {									\
 	static struct lock_class_key __key;				\
@@ -58,6 +65,7 @@ do {									\
 	__init_completion(x);						\
 } while (0)
 #else
+#define init_completion_map(x, m) __init_completion(x)
 #define init_completion(x) __init_completion(x)
 static inline void complete_acquire(struct completion *x) {}
 static inline void complete_release(struct completion *x) {}
@@ -73,6 +81,9 @@ static inline void complete_release_commit(struct completion *x) {}
 	{ 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }
 #endif
 
+#define COMPLETION_INITIALIZER_ONSTACK_MAP(work, map) \
+	(*({ init_completion_map(&(work), &(map)); &(work); }))
+
 #define COMPLETION_INITIALIZER_ONSTACK(work) \
 	(*({ init_completion(&work); &work; }))
 
@@ -102,8 +113,11 @@ static inline void complete_release_commit(struct completion *x) {}
 #ifdef CONFIG_LOCKDEP
 # define DECLARE_COMPLETION_ONSTACK(work) \
 	struct completion work = COMPLETION_INITIALIZER_ONSTACK(work)
+# define DECLARE_COMPLETION_ONSTACK_MAP(work, map) \
+	struct completion work = COMPLETION_INITIALIZER_ONSTACK_MAP(work, map)
 #else
 # define DECLARE_COMPLETION_ONSTACK(work) DECLARE_COMPLETION(work)
+# define DECLARE_COMPLETION_ONSTACK_MAP(work, map) DECLARE_COMPLETION(work)
 #endif
 
 /**