sched/core: Add wrappers for lockdep_(un)pin_lock()

In preparation for adding diagnostic checks to catch missing calls to
update_rq_clock(), provide wrappers for (re)pinning and unpinning
rq->lock.

Because the pending diagnostic checks allow state to be maintained in
rq_flags across pin contexts, swap the 'struct pin_cookie' arguments
for 'struct rq_flags *'.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@unitn.it>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yuyang Du <yuyang.du@intel.com>
Link: http://lkml.kernel.org/r/20160921133813.31976-5-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 23 insertions, 8 deletions

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 7b34c7826ca5..98e7eee07237 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -792,6 +792,26 @@ static inline void rq_clock_skip_update(struct rq *rq, bool skip)
 		rq->clock_skip_update &= ~RQCF_REQ_SKIP;
 }
 
+struct rq_flags {
+	unsigned long flags;
+	struct pin_cookie cookie;
+};
+
+static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
+{
+	rf->cookie = lockdep_pin_lock(&rq->lock);
+}
+
+static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
+{
+	lockdep_unpin_lock(&rq->lock, rf->cookie);
+}
+
+static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
+{
+	lockdep_repin_lock(&rq->lock, rf->cookie);
+}
+
 #ifdef CONFIG_NUMA
 enum numa_topology_type {
 	NUMA_DIRECT,
@@ -1245,7 +1265,7 @@ struct sched_class {
 	 */
 	struct task_struct * (*pick_next_task) (struct rq *rq,
 						struct task_struct *prev,
-						struct pin_cookie cookie);
+						struct rq_flags *rf);
 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
 
 #ifdef CONFIG_SMP
@@ -1501,11 +1521,6 @@ static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
 static inline void sched_avg_update(struct rq *rq) { }
 #endif
 
-struct rq_flags {
-	unsigned long flags;
-	struct pin_cookie cookie;
-};
-
 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
 	__acquires(rq->lock);
 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
@@ -1515,7 +1530,7 @@ struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
 	__releases(rq->lock)
 {
-	lockdep_unpin_lock(&rq->lock, rf->cookie);
+	rq_unpin_lock(rq, rf);
 	raw_spin_unlock(&rq->lock);
 }
 
@@ -1524,7 +1539,7 @@ task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
 	__releases(rq->lock)
 	__releases(p->pi_lock)
 {
-	lockdep_unpin_lock(&rq->lock, rf->cookie);
+	rq_unpin_lock(rq, rf);
 	raw_spin_unlock(&rq->lock);
 	raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
 }