RDS: IB: split mr pool to improve 8K messages performance
[cascardo/linux.git] / net / rds / ib_rdma.c
index bb62024..a234074 100644 (file)
@@ -65,6 +65,7 @@ struct rds_ib_mr {
  * Our own little FMR pool
  */
 struct rds_ib_mr_pool {
+       unsigned int            pool_type;
        struct mutex            flush_lock;             /* serialize fmr invalidate */
        struct delayed_work     flush_worker;           /* flush worker */
 
@@ -234,7 +235,8 @@ void rds_ib_destroy_nodev_conns(void)
                rds_conn_destroy(ic->conn);
 }
 
-struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev)
+struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev,
+                                            int pool_type)
 {
        struct rds_ib_mr_pool *pool;
 
@@ -242,6 +244,7 @@ struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev)
        if (!pool)
                return ERR_PTR(-ENOMEM);
 
+       pool->pool_type = pool_type;
        init_llist_head(&pool->free_list);
        init_llist_head(&pool->drop_list);
        init_llist_head(&pool->clean_list);
@@ -249,28 +252,30 @@ struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev)
        init_waitqueue_head(&pool->flush_wait);
        INIT_DELAYED_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker);
 
-       pool->fmr_attr.max_pages = fmr_message_size;
+       if (pool_type == RDS_IB_MR_1M_POOL) {
+               /* +1 allows for unaligned MRs */
+               pool->fmr_attr.max_pages = RDS_FMR_1M_MSG_SIZE + 1;
+               pool->max_items = RDS_FMR_1M_POOL_SIZE;
+       } else {
+               /* pool_type == RDS_IB_MR_8K_POOL */
+               pool->fmr_attr.max_pages = RDS_FMR_8K_MSG_SIZE + 1;
+               pool->max_items = RDS_FMR_8K_POOL_SIZE;
+       }
+
+       pool->max_free_pinned = pool->max_items * pool->fmr_attr.max_pages / 4;
        pool->fmr_attr.max_maps = rds_ibdev->fmr_max_remaps;
        pool->fmr_attr.page_shift = PAGE_SHIFT;
-       pool->max_free_pinned = rds_ibdev->max_fmrs * fmr_message_size / 4;
-
-       /* We never allow more than max_items MRs to be allocated.
-        * When we exceed more than max_items_soft, we start freeing
-        * items more aggressively.
-        * Make sure that max_items > max_items_soft > max_items / 2
-        */
        pool->max_items_soft = rds_ibdev->max_fmrs * 3 / 4;
-       pool->max_items = rds_ibdev->max_fmrs;
 
        return pool;
 }
 
 void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo)
 {
-       struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool;
+       struct rds_ib_mr_pool *pool_1m = rds_ibdev->mr_1m_pool;
 
-       iinfo->rdma_mr_max = pool->max_items;
-       iinfo->rdma_mr_size = pool->fmr_attr.max_pages;
+       iinfo->rdma_mr_max = pool_1m->max_items;
+       iinfo->rdma_mr_size = pool_1m->fmr_attr.max_pages;
 }
 
 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *pool)
@@ -312,15 +317,29 @@ static inline void wait_clean_list_grace(void)
        }
 }
 
-static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev)
+static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev,
+                                         int npages)
 {
-       struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool;
+       struct rds_ib_mr_pool *pool;
        struct rds_ib_mr *ibmr = NULL;
        int err = 0, iter = 0;
 
+       if (npages <= RDS_FMR_8K_MSG_SIZE)
+               pool = rds_ibdev->mr_8k_pool;
+       else
+               pool = rds_ibdev->mr_1m_pool;
+
        if (atomic_read(&pool->dirty_count) >= pool->max_items / 10)
                queue_delayed_work(rds_ib_fmr_wq, &pool->flush_worker, 10);
 
+       /* Switch pools if one of the pool is reaching upper limit */
+       if (atomic_read(&pool->dirty_count) >=  pool->max_items * 9 / 10) {
+               if (pool->pool_type == RDS_IB_MR_8K_POOL)
+                       pool = rds_ibdev->mr_1m_pool;
+               else
+                       pool = rds_ibdev->mr_8k_pool;
+       }
+
        while (1) {
                ibmr = rds_ib_reuse_fmr(pool);
                if (ibmr)
@@ -341,12 +360,18 @@ static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev)
                atomic_dec(&pool->item_count);
 
                if (++iter > 2) {
-                       rds_ib_stats_inc(s_ib_rdma_mr_pool_depleted);
+                       if (pool->pool_type == RDS_IB_MR_8K_POOL)
+                               rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_depleted);
+                       else
+                               rds_ib_stats_inc(s_ib_rdma_mr_1m_pool_depleted);
                        return ERR_PTR(-EAGAIN);
                }
 
                /* We do have some empty MRs. Flush them out. */
-               rds_ib_stats_inc(s_ib_rdma_mr_pool_wait);
+               if (pool->pool_type == RDS_IB_MR_8K_POOL)
+                       rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_wait);
+               else
+                       rds_ib_stats_inc(s_ib_rdma_mr_1m_pool_wait);
                rds_ib_flush_mr_pool(pool, 0, &ibmr);
                if (ibmr)
                        return ibmr;
@@ -371,7 +396,12 @@ static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev)
                goto out_no_cigar;
        }
 
-       rds_ib_stats_inc(s_ib_rdma_mr_alloc);
+       ibmr->pool = pool;
+       if (pool->pool_type == RDS_IB_MR_8K_POOL)
+               rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
+       else
+               rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
+
        return ibmr;
 
 out_no_cigar:
@@ -427,7 +457,7 @@ static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibm
        }
 
        page_cnt += len >> PAGE_SHIFT;
-       if (page_cnt > fmr_message_size)
+       if (page_cnt > ibmr->pool->fmr_attr.max_pages)
                return -EINVAL;
 
        dma_pages = kmalloc_node(sizeof(u64) * page_cnt, GFP_ATOMIC,
@@ -459,7 +489,10 @@ static int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibm
        ibmr->sg_dma_len = sg_dma_len;
        ibmr->remap_count++;
 
-       rds_ib_stats_inc(s_ib_rdma_mr_used);
+       if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+               rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
+       else
+               rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
        ret = 0;
 
 out:
@@ -591,7 +624,7 @@ static void list_to_llist_nodes(struct rds_ib_mr_pool *pool,
  * to free as many MRs as needed to get back to this limit.
  */
 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
-                               int free_all, struct rds_ib_mr **ibmr_ret)
+                               int free_all, struct rds_ib_mr **ibmr_ret)
 {
        struct rds_ib_mr *ibmr, *next;
        struct llist_node *clean_nodes;
@@ -602,11 +635,14 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
        unsigned int nfreed = 0, dirty_to_clean = 0, free_goal;
        int ret = 0;
 
-       rds_ib_stats_inc(s_ib_rdma_mr_pool_flush);
+       if (pool->pool_type == RDS_IB_MR_8K_POOL)
+               rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_flush);
+       else
+               rds_ib_stats_inc(s_ib_rdma_mr_1m_pool_flush);
 
        if (ibmr_ret) {
                DEFINE_WAIT(wait);
-               while(!mutex_trylock(&pool->flush_lock)) {
+               while (!mutex_trylock(&pool->flush_lock)) {
                        ibmr = rds_ib_reuse_fmr(pool);
                        if (ibmr) {
                                *ibmr_ret = ibmr;
@@ -663,8 +699,12 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
        list_for_each_entry_safe(ibmr, next, &unmap_list, unmap_list) {
                unpinned += ibmr->sg_len;
                __rds_ib_teardown_mr(ibmr);
-               if (nfreed < free_goal || ibmr->remap_count >= pool->fmr_attr.max_maps) {
-                       rds_ib_stats_inc(s_ib_rdma_mr_free);
+               if (nfreed < free_goal ||
+                   ibmr->remap_count >= pool->fmr_attr.max_maps) {
+                       if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+                               rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
+                       else
+                               rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
                        list_del(&ibmr->unmap_list);
                        ib_dealloc_fmr(ibmr->fmr);
                        kfree(ibmr);
@@ -756,10 +796,11 @@ void rds_ib_flush_mrs(void)
 
        down_read(&rds_ib_devices_lock);
        list_for_each_entry(rds_ibdev, &rds_ib_devices, list) {
-               struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool;
+               if (rds_ibdev->mr_8k_pool)
+                       rds_ib_flush_mr_pool(rds_ibdev->mr_8k_pool, 0, NULL);
 
-               if (pool)
-                       rds_ib_flush_mr_pool(pool, 0, NULL);
+               if (rds_ibdev->mr_1m_pool)
+                       rds_ib_flush_mr_pool(rds_ibdev->mr_1m_pool, 0, NULL);
        }
        up_read(&rds_ib_devices_lock);
 }
@@ -777,12 +818,12 @@ void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
                goto out;
        }
 
-       if (!rds_ibdev->mr_pool) {
+       if (!rds_ibdev->mr_8k_pool || !rds_ibdev->mr_1m_pool) {
                ret = -ENODEV;
                goto out;
        }
 
-       ibmr = rds_ib_alloc_fmr(rds_ibdev);
+       ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
        if (IS_ERR(ibmr)) {
                rds_ib_dev_put(rds_ibdev);
                return ibmr;