]> Pileus Git - ~andy/linux/blobdiff - drivers/block/null_blk.c
Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-block
[~andy/linux] / drivers / block / null_blk.c
index ea192ec029c45bf7354d8184b44e1eb460cdbf77..3107282a9741f96665a2805b08217d3209c27bf7 100644 (file)
@@ -1,4 +1,5 @@
 #include <linux/module.h>
+
 #include <linux/moduleparam.h>
 #include <linux/sched.h>
 #include <linux/fs.h>
@@ -65,7 +66,7 @@ enum {
        NULL_Q_MQ               = 2,
 };
 
-static int submit_queues = 1;
+static int submit_queues;
 module_param(submit_queues, int, S_IRUGO);
 MODULE_PARM_DESC(submit_queues, "Number of submission queues");
 
@@ -101,9 +102,9 @@ static int hw_queue_depth = 64;
 module_param(hw_queue_depth, int, S_IRUGO);
 MODULE_PARM_DESC(hw_queue_depth, "Queue depth for each hardware queue. Default: 64");
 
-static bool use_per_node_hctx = true;
+static bool use_per_node_hctx = false;
 module_param(use_per_node_hctx, bool, S_IRUGO);
-MODULE_PARM_DESC(use_per_node_hctx, "Use per-node allocation for hardware context queues. Default: true");
+MODULE_PARM_DESC(use_per_node_hctx, "Use per-node allocation for hardware context queues. Default: false");
 
 static void put_tag(struct nullb_queue *nq, unsigned int tag)
 {
@@ -346,8 +347,37 @@ static int null_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *rq)
 
 static struct blk_mq_hw_ctx *null_alloc_hctx(struct blk_mq_reg *reg, unsigned int hctx_index)
 {
-       return kzalloc_node(sizeof(struct blk_mq_hw_ctx), GFP_KERNEL,
-                               hctx_index);
+       int b_size = DIV_ROUND_UP(reg->nr_hw_queues, nr_online_nodes);
+       int tip = (reg->nr_hw_queues % nr_online_nodes);
+       int node = 0, i, n;
+
+       /*
+        * Split submit queues evenly wrt to the number of nodes. If uneven,
+        * fill the first buckets with one extra, until the rest is filled with
+        * no extra.
+        */
+       for (i = 0, n = 1; i < hctx_index; i++, n++) {
+               if (n % b_size == 0) {
+                       n = 0;
+                       node++;
+
+                       tip--;
+                       if (!tip)
+                               b_size = reg->nr_hw_queues / nr_online_nodes;
+               }
+       }
+
+       /*
+        * A node might not be online, therefore map the relative node id to the
+        * real node id.
+        */
+       for_each_online_node(n) {
+               if (!node)
+                       break;
+               node--;
+       }
+
+       return kzalloc_node(sizeof(struct blk_mq_hw_ctx), GFP_KERNEL, n);
 }
 
 static void null_free_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_index)
@@ -355,16 +385,24 @@ static void null_free_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_index)
        kfree(hctx);
 }
 
+static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq)
+{
+       BUG_ON(!nullb);
+       BUG_ON(!nq);
+
+       init_waitqueue_head(&nq->wait);
+       nq->queue_depth = nullb->queue_depth;
+}
+
 static int null_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
                          unsigned int index)
 {
        struct nullb *nullb = data;
        struct nullb_queue *nq = &nullb->queues[index];
 
-       init_waitqueue_head(&nq->wait);
-       nq->queue_depth = nullb->queue_depth;
-       nullb->nr_queues++;
        hctx->driver_data = nq;
+       null_init_queue(nullb, nq);
+       nullb->nr_queues++;
 
        return 0;
 }
@@ -387,10 +425,7 @@ static void null_del_dev(struct nullb *nullb)
        list_del_init(&nullb->list);
 
        del_gendisk(nullb->disk);
-       if (queue_mode == NULL_Q_MQ)
-               blk_mq_free_queue(nullb->q);
-       else
-               blk_cleanup_queue(nullb->q);
+       blk_cleanup_queue(nullb->q);
        put_disk(nullb->disk);
        kfree(nullb);
 }
@@ -417,13 +452,13 @@ static int setup_commands(struct nullb_queue *nq)
 
        nq->cmds = kzalloc(nq->queue_depth * sizeof(*cmd), GFP_KERNEL);
        if (!nq->cmds)
-               return 1;
+               return -ENOMEM;
 
        tag_size = ALIGN(nq->queue_depth, BITS_PER_LONG) / BITS_PER_LONG;
        nq->tag_map = kzalloc(tag_size * sizeof(unsigned long), GFP_KERNEL);
        if (!nq->tag_map) {
                kfree(nq->cmds);
-               return 1;
+               return -ENOMEM;
        }
 
        for (i = 0; i < nq->queue_depth; i++) {
@@ -454,33 +489,37 @@ static void cleanup_queues(struct nullb *nullb)
 
 static int setup_queues(struct nullb *nullb)
 {
-       struct nullb_queue *nq;
-       int i;
-
-       nullb->queues = kzalloc(submit_queues * sizeof(*nq), GFP_KERNEL);
+       nullb->queues = kzalloc(submit_queues * sizeof(struct nullb_queue),
+                                                               GFP_KERNEL);
        if (!nullb->queues)
-               return 1;
+               return -ENOMEM;
 
        nullb->nr_queues = 0;
        nullb->queue_depth = hw_queue_depth;
 
-       if (queue_mode == NULL_Q_MQ)
-               return 0;
+       return 0;
+}
+
+static int init_driver_queues(struct nullb *nullb)
+{
+       struct nullb_queue *nq;
+       int i, ret = 0;
 
        for (i = 0; i < submit_queues; i++) {
                nq = &nullb->queues[i];
-               init_waitqueue_head(&nq->wait);
-               nq->queue_depth = hw_queue_depth;
-               if (setup_commands(nq))
-                       break;
+
+               null_init_queue(nullb, nq);
+
+               ret = setup_commands(nq);
+               if (ret)
+                       goto err_queue;
                nullb->nr_queues++;
        }
 
-       if (i == submit_queues)
-               return 0;
-
+       return 0;
+err_queue:
        cleanup_queues(nullb);
-       return 1;
+       return ret;
 }
 
 static int null_add_dev(void)
@@ -495,34 +534,36 @@ static int null_add_dev(void)
 
        spin_lock_init(&nullb->lock);
 
+       if (queue_mode == NULL_Q_MQ && use_per_node_hctx)
+               submit_queues = nr_online_nodes;
+
        if (setup_queues(nullb))
                goto err;
 
        if (queue_mode == NULL_Q_MQ) {
                null_mq_reg.numa_node = home_node;
                null_mq_reg.queue_depth = hw_queue_depth;
+               null_mq_reg.nr_hw_queues = submit_queues;
 
                if (use_per_node_hctx) {
                        null_mq_reg.ops->alloc_hctx = null_alloc_hctx;
                        null_mq_reg.ops->free_hctx = null_free_hctx;
-
-                       null_mq_reg.nr_hw_queues = nr_online_nodes;
                } else {
                        null_mq_reg.ops->alloc_hctx = blk_mq_alloc_single_hw_queue;
                        null_mq_reg.ops->free_hctx = blk_mq_free_single_hw_queue;
-
-                       null_mq_reg.nr_hw_queues = submit_queues;
                }
 
                nullb->q = blk_mq_init_queue(&null_mq_reg, nullb);
        } else if (queue_mode == NULL_Q_BIO) {
                nullb->q = blk_alloc_queue_node(GFP_KERNEL, home_node);
                blk_queue_make_request(nullb->q, null_queue_bio);
+               init_driver_queues(nullb);
        } else {
                nullb->q = blk_init_queue_node(null_request_fn, &nullb->lock, home_node);
                blk_queue_prep_rq(nullb->q, null_rq_prep_fn);
                if (nullb->q)
                        blk_queue_softirq_done(nullb->q, null_softirq_done_fn);
+               init_driver_queues(nullb);
        }
 
        if (!nullb->q)
@@ -534,10 +575,7 @@ static int null_add_dev(void)
        disk = nullb->disk = alloc_disk_node(1, home_node);
        if (!disk) {
 queue_fail:
-               if (queue_mode == NULL_Q_MQ)
-                       blk_mq_free_queue(nullb->q);
-               else
-                       blk_cleanup_queue(nullb->q);
+               blk_cleanup_queue(nullb->q);
                cleanup_queues(nullb);
 err:
                kfree(nullb);
@@ -578,8 +616,19 @@ static int __init null_init(void)
                irqmode = NULL_IRQ_NONE;
        }
 #endif
+       if (bs > PAGE_SIZE) {
+               pr_warn("null_blk: invalid block size\n");
+               pr_warn("null_blk: defaults block size to %lu\n", PAGE_SIZE);
+               bs = PAGE_SIZE;
+       }
 
-       if (submit_queues > nr_cpu_ids)
+       if (queue_mode == NULL_Q_MQ && use_per_node_hctx) {
+               if (submit_queues < nr_online_nodes) {
+                       pr_warn("null_blk: submit_queues param is set to %u.",
+                                                       nr_online_nodes);
+                       submit_queues = nr_online_nodes;
+               }
+       } else if (submit_queues > nr_cpu_ids)
                submit_queues = nr_cpu_ids;
        else if (!submit_queues)
                submit_queues = 1;