sbitmap: push alloc policy into sbitmap_queue

Again, there's no point in passing this in every time. Make it part of
struct sbitmap_queue and clean up the API.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index c9a22db..e1c2bed 100644 (file)
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -91,14 +91,11 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
        return atomic_read(&hctx->nr_active) < depth;
 }
 
-#define BT_ALLOC_RR(tags) (tags->alloc_policy == BLK_TAG_ALLOC_RR)
-
-static int __bt_get(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt,
-                   struct blk_mq_tags *tags)
+static int __bt_get(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt)
 {
        if (!hctx_may_queue(hctx, bt))
                return -1;
-       return __sbitmap_queue_get(bt, BT_ALLOC_RR(tags));
+       return __sbitmap_queue_get(bt);
 }
 
 static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt,
@@ -108,7 +105,7 @@ static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt,
        DEFINE_WAIT(wait);
        int tag;
 
-       tag = __bt_get(hctx, bt, tags);
+       tag = __bt_get(hctx, bt);
        if (tag != -1)
                return tag;
 
@@ -119,7 +116,7 @@ static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt,
        do {
                prepare_to_wait(&ws->wait, &wait, TASK_UNINTERRUPTIBLE);
 
-               tag = __bt_get(hctx, bt, tags);
+               tag = __bt_get(hctx, bt);
                if (tag != -1)
                        break;
 
@@ -136,7 +133,7 @@ static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt,
                 * Retry tag allocation after running the hardware queue,
                 * as running the queue may also have found completions.
                 */
-               tag = __bt_get(hctx, bt, tags);
+               tag = __bt_get(hctx, bt);
                if (tag != -1)
                        break;
 
@@ -206,12 +203,10 @@ void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
                const int real_tag = tag - tags->nr_reserved_tags;
 
                BUG_ON(real_tag >= tags->nr_tags);
-               sbitmap_queue_clear(&tags->bitmap_tags, real_tag,
-                                   BT_ALLOC_RR(tags), ctx->cpu);
+               sbitmap_queue_clear(&tags->bitmap_tags, real_tag, ctx->cpu);
        } else {
                BUG_ON(tag >= tags->nr_reserved_tags);
-               sbitmap_queue_clear(&tags->breserved_tags, tag,
-                                   BT_ALLOC_RR(tags), ctx->cpu);
+               sbitmap_queue_clear(&tags->breserved_tags, tag, ctx->cpu);
        }
 }
 
@@ -363,21 +358,23 @@ static unsigned int bt_unused_tags(const struct sbitmap_queue *bt)
        return bt->sb.depth - sbitmap_weight(&bt->sb);
 }
 
-static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth, int node)
+static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth,
+                   bool round_robin, int node)
 {
-       return sbitmap_queue_init_node(bt, depth, -1, GFP_KERNEL, node);
+       return sbitmap_queue_init_node(bt, depth, -1, round_robin, GFP_KERNEL,
+                                      node);
 }
 
 static struct blk_mq_tags *blk_mq_init_bitmap_tags(struct blk_mq_tags *tags,
                                                   int node, int alloc_policy)
 {
        unsigned int depth = tags->nr_tags - tags->nr_reserved_tags;
+       bool round_robin = alloc_policy == BLK_TAG_ALLOC_RR;
 
-       tags->alloc_policy = alloc_policy;
-
-       if (bt_alloc(&tags->bitmap_tags, depth, node))
+       if (bt_alloc(&tags->bitmap_tags, depth, round_robin, node))
                goto free_tags;
-       if (bt_alloc(&tags->breserved_tags, tags->nr_reserved_tags, node))
+       if (bt_alloc(&tags->breserved_tags, tags->nr_reserved_tags, round_robin,
+                    node))
                goto free_bitmap_tags;
 
        return tags;

diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h
index 2b1d52e..f90b850 100644 (file)
--- a/block/blk-mq-tag.h
+++ b/block/blk-mq-tag.h
@@ -18,7 +18,6 @@ struct blk_mq_tags {
        struct request **rqs;
        struct list_head page_list;
 
-       int alloc_policy;
        cpumask_var_t cpumask;
 };
 

diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h
index 6745545..f017fd6 100644 (file)
--- a/include/linux/sbitmap.h
+++ b/include/linux/sbitmap.h
@@ -122,6 +122,11 @@ struct sbitmap_queue {
         * @ws: Wait queues.
         */
        struct sbq_wait_state *ws;
+
+       /**
+        * @round_robin: Allocate bits in strict round-robin order.
+        */
+       bool round_robin;
 };
 
 /**
@@ -259,13 +264,14 @@ unsigned int sbitmap_weight(const struct sbitmap *sb);
  * @sbq: Bitmap queue to initialize.
  * @depth: See sbitmap_init_node().
  * @shift: See sbitmap_init_node().
+ * @round_robin: See sbitmap_get().
  * @flags: Allocation flags.
  * @node: Memory node to allocate on.
  *
  * Return: Zero on success or negative errno on failure.
  */
 int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth,
-                           int shift, gfp_t flags, int node);
+                           int shift, bool round_robin, gfp_t flags, int node);
 
 /**
  * sbitmap_queue_free() - Free memory used by a &struct sbitmap_queue.
@@ -294,29 +300,27 @@ void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth);
  * __sbitmap_queue_get() - Try to allocate a free bit from a &struct
  * sbitmap_queue with preemption already disabled.
  * @sbq: Bitmap queue to allocate from.
- * @round_robin: See sbitmap_get().
  *
  * Return: Non-negative allocated bit number if successful, -1 otherwise.
  */
-int __sbitmap_queue_get(struct sbitmap_queue *sbq, bool round_robin);
+int __sbitmap_queue_get(struct sbitmap_queue *sbq);
 
 /**
  * sbitmap_queue_get() - Try to allocate a free bit from a &struct
  * sbitmap_queue.
  * @sbq: Bitmap queue to allocate from.
- * @round_robin: See sbitmap_get().
  * @cpu: Output parameter; will contain the CPU we ran on (e.g., to be passed to
  *       sbitmap_queue_clear()).
  *
  * Return: Non-negative allocated bit number if successful, -1 otherwise.
  */
-static inline int sbitmap_queue_get(struct sbitmap_queue *sbq, bool round_robin,
+static inline int sbitmap_queue_get(struct sbitmap_queue *sbq,
                                    unsigned int *cpu)
 {
        int nr;
 
        *cpu = get_cpu();
-       nr = __sbitmap_queue_get(sbq, round_robin);
+       nr = __sbitmap_queue_get(sbq);
        put_cpu();
        return nr;
 }
@@ -326,11 +330,10 @@ static inline int sbitmap_queue_get(struct sbitmap_queue *sbq, bool round_robin,
  * &struct sbitmap_queue.
  * @sbq: Bitmap to free from.
  * @nr: Bit number to free.
- * @round_robin: See sbitmap_get().
  * @cpu: CPU the bit was allocated on.
  */
 void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr,
-                        bool round_robin, unsigned int cpu);
+                        unsigned int cpu);
 
 static inline int sbq_index_inc(int index)
 {

diff --git a/lib/sbitmap.c b/lib/sbitmap.c
index 1651ad9..be55f74 100644 (file)
--- a/lib/sbitmap.c
+++ b/lib/sbitmap.c
@@ -196,7 +196,7 @@ static unsigned int sbq_calc_wake_batch(unsigned int depth)
 }
 
 int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth,
-                           int shift, gfp_t flags, int node)
+                           int shift, bool round_robin, gfp_t flags, int node)
 {
        int ret;
        int i;
@@ -225,6 +225,8 @@ int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth,
                init_waitqueue_head(&sbq->ws[i].wait);
                atomic_set(&sbq->ws[i].wait_cnt, sbq->wake_batch);
        }
+
+       sbq->round_robin = round_robin;
        return 0;
 }
 EXPORT_SYMBOL_GPL(sbitmap_queue_init_node);
@@ -236,18 +238,18 @@ void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth)
 }
 EXPORT_SYMBOL_GPL(sbitmap_queue_resize);
 
-int __sbitmap_queue_get(struct sbitmap_queue *sbq, bool round_robin)
+int __sbitmap_queue_get(struct sbitmap_queue *sbq)
 {
        unsigned int hint;
        int nr;
 
        hint = this_cpu_read(*sbq->alloc_hint);
-       nr = sbitmap_get(&sbq->sb, hint, round_robin);
+       nr = sbitmap_get(&sbq->sb, hint, sbq->round_robin);
 
        if (nr == -1) {
                /* If the map is full, a hint won't do us much good. */
                this_cpu_write(*sbq->alloc_hint, 0);
-       } else if (nr == hint || unlikely(round_robin)) {
+       } else if (nr == hint || unlikely(sbq->round_robin)) {
                /* Only update the hint if we used it. */
                hint = nr + 1;
                if (hint >= sbq->sb.depth - 1)
@@ -304,11 +306,11 @@ static void sbq_wake_up(struct sbitmap_queue *sbq)
 }
 
 void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr,
-                        bool round_robin, unsigned int cpu)
+                        unsigned int cpu)
 {
        sbitmap_clear_bit(&sbq->sb, nr);
        sbq_wake_up(sbq);
-       if (likely(!round_robin))
+       if (likely(!sbq->round_robin))
                *per_cpu_ptr(sbq->alloc_hint, cpu) = nr;
 }
 EXPORT_SYMBOL_GPL(sbitmap_queue_clear);