mm/memory_hotplug: introduce add_memory_driver_managed()

[linux-2.6-microblaze.git] / include / linux / blk-cgroup.h

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 35f8ffe..a57ebe2 100644 (file)
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -607,12 +607,14 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q,
                u64_stats_update_begin(&bis->sync);
 
                /*
-                * If the bio is flagged with BIO_QUEUE_ENTERED it means this
-                * is a split bio and we would have already accounted for the
-                * size of the bio.
+                * If the bio is flagged with BIO_CGROUP_ACCT it means this is a
+                * split bio and we would have already accounted for the size of
+                * the bio.
                 */
-               if (!bio_flagged(bio, BIO_QUEUE_ENTERED))
+               if (!bio_flagged(bio, BIO_CGROUP_ACCT)) {
+                       bio_set_flag(bio, BIO_CGROUP_ACCT);
                        bis->cur.bytes[rwd] += bio->bi_iter.bi_size;
+               }
                bis->cur.ios[rwd]++;
 
                u64_stats_update_end(&bis->sync);
@@ -629,6 +631,8 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q,
 
 static inline void blkcg_use_delay(struct blkcg_gq *blkg)
 {
+       if (WARN_ON_ONCE(atomic_read(&blkg->use_delay) < 0))
+               return;
        if (atomic_add_return(1, &blkg->use_delay) == 1)
                atomic_inc(&blkg->blkcg->css.cgroup->congestion_count);
 }
@@ -637,6 +641,8 @@ static inline int blkcg_unuse_delay(struct blkcg_gq *blkg)
 {
        int old = atomic_read(&blkg->use_delay);
 
+       if (WARN_ON_ONCE(old < 0))
+               return 0;
        if (old == 0)
                return 0;
 
@@ -661,20 +667,39 @@ static inline int blkcg_unuse_delay(struct blkcg_gq *blkg)
        return 1;
 }
 
+/**
+ * blkcg_set_delay - Enable allocator delay mechanism with the specified delay amount
+ * @blkg: target blkg
+ * @delay: delay duration in nsecs
+ *
+ * When enabled with this function, the delay is not decayed and must be
+ * explicitly cleared with blkcg_clear_delay(). Must not be mixed with
+ * blkcg_[un]use_delay() and blkcg_add_delay() usages.
+ */
+static inline void blkcg_set_delay(struct blkcg_gq *blkg, u64 delay)
+{
+       int old = atomic_read(&blkg->use_delay);
+
+       /* We only want 1 person setting the congestion count for this blkg. */
+       if (!old && atomic_cmpxchg(&blkg->use_delay, old, -1) == old)
+               atomic_inc(&blkg->blkcg->css.cgroup->congestion_count);
+
+       atomic64_set(&blkg->delay_nsec, delay);
+}
+
+/**
+ * blkcg_clear_delay - Disable allocator delay mechanism
+ * @blkg: target blkg
+ *
+ * Disable use_delay mechanism. See blkcg_set_delay().
+ */
 static inline void blkcg_clear_delay(struct blkcg_gq *blkg)
 {
        int old = atomic_read(&blkg->use_delay);
-       if (!old)
-               return;
+
        /* We only want 1 person clearing the congestion count for this blkg. */
-       while (old) {
-               int cur = atomic_cmpxchg(&blkg->use_delay, old, 0);
-               if (cur == old) {
-                       atomic_dec(&blkg->blkcg->css.cgroup->congestion_count);
-                       break;
-               }
-               old = cur;
-       }
+       if (old && atomic_cmpxchg(&blkg->use_delay, old, 0) == old)
+               atomic_dec(&blkg->blkcg->css.cgroup->congestion_count);
 }
 
 void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta);