[net-next][PATCH v2 07/13] RDS: IB: move FMR code to its own file

From: Santosh Shilimkar
Date: Sat Feb 27 2016 - 21:22:28 EST


No functional change.

Signed-off-by: Santosh Shilimkar <ssantosh@xxxxxxxxxx>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxxxxxx>
---
net/rds/ib_fmr.c | 126 +++++++++++++++++++++++++++++++++---------------------
net/rds/ib_mr.h | 6 +++
net/rds/ib_rdma.c | 108 ++++++++++++++++++++++------------------------
3 files changed, 134 insertions(+), 106 deletions(-)

diff --git a/net/rds/ib_fmr.c b/net/rds/ib_fmr.c
index 74f2c21..4fe8f4f 100644
--- a/net/rds/ib_fmr.c
+++ b/net/rds/ib_fmr.c
@@ -37,61 +37,16 @@ struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages)
struct rds_ib_mr_pool *pool;
struct rds_ib_mr *ibmr = NULL;
struct rds_ib_fmr *fmr;
- int err = 0, iter = 0;
+ int err = 0;

if (npages <= RDS_MR_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_mr_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_mr(pool);
- if (ibmr)
- return ibmr;
-
- /* No clean MRs - now we have the choice of either
- * allocating a fresh MR up to the limit imposed by the
- * driver, or flush any dirty unused MRs.
- * We try to avoid stalling in the send path if possible,
- * so we allocate as long as we're allowed to.
- *
- * We're fussy with enforcing the FMR limit, though. If the
- * driver tells us we can't use more than N fmrs, we shouldn't
- * start arguing with it
- */
- if (atomic_inc_return(&pool->item_count) <= pool->max_items)
- break;
-
- atomic_dec(&pool->item_count);
-
- if (++iter > 2) {
- 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. */
- 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;
- }
+ ibmr = rds_ib_try_reuse_ibmr(pool);
+ if (ibmr)
+ return ibmr;

ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
rdsibdev_to_node(rds_ibdev));
@@ -218,3 +173,76 @@ out:

return ret;
}
+
+struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *rds_ibdev,
+ struct scatterlist *sg,
+ unsigned long nents,
+ u32 *key)
+{
+ struct rds_ib_mr *ibmr = NULL;
+ struct rds_ib_fmr *fmr;
+ int ret;
+
+ ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
+ if (IS_ERR(ibmr))
+ return ibmr;
+
+ ibmr->device = rds_ibdev;
+ fmr = &ibmr->u.fmr;
+ ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
+ if (ret == 0)
+ *key = fmr->fmr->rkey;
+ else
+ rds_ib_free_mr(ibmr, 0);
+
+ return ibmr;
+}
+
+void rds_ib_unreg_fmr(struct list_head *list, unsigned int *nfreed,
+ unsigned long *unpinned, unsigned int goal)
+{
+ struct rds_ib_mr *ibmr, *next;
+ struct rds_ib_fmr *fmr;
+ LIST_HEAD(fmr_list);
+ int ret = 0;
+ unsigned int freed = *nfreed;
+
+ /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
+ list_for_each_entry(ibmr, list, unmap_list) {
+ fmr = &ibmr->u.fmr;
+ list_add(&fmr->fmr->list, &fmr_list);
+ }
+
+ ret = ib_unmap_fmr(&fmr_list);
+ if (ret)
+ pr_warn("RDS/IB: FMR invalidation failed (err=%d)\n", ret);
+
+ /* Now we can destroy the DMA mapping and unpin any pages */
+ list_for_each_entry_safe(ibmr, next, list, unmap_list) {
+ fmr = &ibmr->u.fmr;
+ *unpinned += ibmr->sg_len;
+ __rds_ib_teardown_mr(ibmr);
+ if (freed < goal ||
+ ibmr->remap_count >= ibmr->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(fmr->fmr);
+ kfree(ibmr);
+ freed++;
+ }
+ }
+ *nfreed = freed;
+}
+
+void rds_ib_free_fmr_list(struct rds_ib_mr *ibmr)
+{
+ struct rds_ib_mr_pool *pool = ibmr->pool;
+
+ if (ibmr->remap_count >= pool->fmr_attr.max_maps)
+ llist_add(&ibmr->llnode, &pool->drop_list);
+ else
+ llist_add(&ibmr->llnode, &pool->free_list);
+}
diff --git a/net/rds/ib_mr.h b/net/rds/ib_mr.h
index 309ad59..f5c1fcb 100644
--- a/net/rds/ib_mr.h
+++ b/net/rds/ib_mr.h
@@ -113,4 +113,10 @@ int rds_ib_map_fmr(struct rds_ib_device *, struct rds_ib_mr *,
struct scatterlist *, unsigned int);
struct rds_ib_mr *rds_ib_reuse_mr(struct rds_ib_mr_pool *);
int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *, int, struct rds_ib_mr **);
+struct rds_ib_mr *rds_ib_reg_fmr(struct rds_ib_device *, struct scatterlist *,
+ unsigned long, u32 *);
+struct rds_ib_mr *rds_ib_try_reuse_ibmr(struct rds_ib_mr_pool *);
+void rds_ib_unreg_fmr(struct list_head *, unsigned int *,
+ unsigned long *, unsigned int);
+void rds_ib_free_fmr_list(struct rds_ib_mr *);
#endif
diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index 9e608d9..0e84843 100644
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -333,15 +333,12 @@ static void list_to_llist_nodes(struct rds_ib_mr_pool *pool,
int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
int free_all, struct rds_ib_mr **ibmr_ret)
{
- struct rds_ib_mr *ibmr, *next;
- struct rds_ib_fmr *fmr;
+ struct rds_ib_mr *ibmr;
struct llist_node *clean_nodes;
struct llist_node *clean_tail;
LIST_HEAD(unmap_list);
- LIST_HEAD(fmr_list);
unsigned long unpinned = 0;
unsigned int nfreed = 0, dirty_to_clean = 0, free_goal;
- int ret = 0;

if (pool->pool_type == RDS_IB_MR_8K_POOL)
rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_flush);
@@ -395,33 +392,7 @@ int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
if (list_empty(&unmap_list))
goto out;

- /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
- list_for_each_entry(ibmr, &unmap_list, unmap_list) {
- fmr = &ibmr->u.fmr;
- list_add(&fmr->fmr->list, &fmr_list);
- }
-
- ret = ib_unmap_fmr(&fmr_list);
- if (ret)
- printk(KERN_WARNING "RDS/IB: ib_unmap_fmr failed (err=%d)\n", ret);
-
- /* Now we can destroy the DMA mapping and unpin any pages */
- list_for_each_entry_safe(ibmr, next, &unmap_list, unmap_list) {
- unpinned += ibmr->sg_len;
- fmr = &ibmr->u.fmr;
- __rds_ib_teardown_mr(ibmr);
- 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(fmr->fmr);
- kfree(ibmr);
- nfreed++;
- }
- }
+ rds_ib_unreg_fmr(&unmap_list, &nfreed, &unpinned, free_goal);

if (!list_empty(&unmap_list)) {
/* we have to make sure that none of the things we're about
@@ -454,7 +425,47 @@ out:
if (waitqueue_active(&pool->flush_wait))
wake_up(&pool->flush_wait);
out_nolock:
- return ret;
+ return 0;
+}
+
+struct rds_ib_mr *rds_ib_try_reuse_ibmr(struct rds_ib_mr_pool *pool)
+{
+ struct rds_ib_mr *ibmr = NULL;
+ int iter = 0;
+
+ if (atomic_read(&pool->dirty_count) >= pool->max_items_soft / 10)
+ queue_delayed_work(rds_ib_mr_wq, &pool->flush_worker, 10);
+
+ while (1) {
+ ibmr = rds_ib_reuse_mr(pool);
+ if (ibmr)
+ return ibmr;
+
+ if (atomic_inc_return(&pool->item_count) <= pool->max_items)
+ break;
+
+ atomic_dec(&pool->item_count);
+
+ if (++iter > 2) {
+ 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. */
+ 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;
+ }
+
+ return ibmr;
}

static void rds_ib_mr_pool_flush_worker(struct work_struct *work)
@@ -473,10 +484,7 @@ void rds_ib_free_mr(void *trans_private, int invalidate)
rdsdebug("RDS/IB: free_mr nents %u\n", ibmr->sg_len);

/* Return it to the pool's free list */
- if (ibmr->remap_count >= pool->fmr_attr.max_maps)
- llist_add(&ibmr->llnode, &pool->drop_list);
- else
- llist_add(&ibmr->llnode, &pool->free_list);
+ rds_ib_free_fmr_list(ibmr);

atomic_add(ibmr->sg_len, &pool->free_pinned);
atomic_inc(&pool->dirty_count);
@@ -521,7 +529,6 @@ void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
{
struct rds_ib_device *rds_ibdev;
struct rds_ib_mr *ibmr = NULL;
- struct rds_ib_fmr *fmr;
int ret;

rds_ibdev = rds_ib_get_device(rs->rs_bound_addr);
@@ -535,30 +542,17 @@ void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
goto out;
}

- ibmr = rds_ib_alloc_fmr(rds_ibdev, nents);
- if (IS_ERR(ibmr)) {
- rds_ib_dev_put(rds_ibdev);
- return ibmr;
- }
-
- fmr = &ibmr->u.fmr;
- ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents);
- if (ret == 0)
- *key_ret = fmr->fmr->rkey;
- else
- printk(KERN_WARNING "RDS/IB: map_fmr failed (errno=%d)\n", ret);
-
- ibmr->device = rds_ibdev;
- rds_ibdev = NULL;
+ ibmr = rds_ib_reg_fmr(rds_ibdev, sg, nents, key_ret);
+ if (ibmr)
+ rds_ibdev = NULL;

out:
- if (ret) {
- if (ibmr)
- rds_ib_free_mr(ibmr, 0);
- ibmr = ERR_PTR(ret);
- }
+ if (!ibmr)
+ pr_warn("RDS/IB: rds_ib_get_mr failed (errno=%d)\n", ret);
+
if (rds_ibdev)
rds_ib_dev_put(rds_ibdev);
+
return ibmr;
}

--
1.9.1