Continuing to decouple mcg from rxe pools. Create red-black tree code
in rxe_mcast.c to hold mcg index.
Signed-off-by: Bob Pearson <rpearsonhpe@xxxxxxxxx>
---
drivers/infiniband/sw/rxe/rxe.c | 1 +
drivers/infiniband/sw/rxe/rxe_loc.h | 3 +-
drivers/infiniband/sw/rxe/rxe_mcast.c | 187 +++++++++++++++++++++-----
drivers/infiniband/sw/rxe/rxe_recv.c | 4 +-
drivers/infiniband/sw/rxe/rxe_verbs.h | 3 +
5 files changed, 159 insertions(+), 39 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
index 46a07e2d9dcf..310e184ae9e8 100644
--- a/drivers/infiniband/sw/rxe/rxe.c
+++ b/drivers/infiniband/sw/rxe/rxe.c
@@ -199,6 +199,7 @@ static int rxe_init(struct rxe_dev *rxe)
return err;
spin_lock_init(&rxe->mcg_lock);
+ rxe->mcg_tree = RB_ROOT;
/* init pending mmap list */
spin_lock_init(&rxe->mmap_offset_lock);
diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h b/drivers/infiniband/sw/rxe/rxe_loc.h
index af40e3c212fb..d9faf3a1ee61 100644
--- a/drivers/infiniband/sw/rxe/rxe_loc.h
+++ b/drivers/infiniband/sw/rxe/rxe_loc.h
@@ -40,9 +40,10 @@ void rxe_cq_disable(struct rxe_cq *cq);
void rxe_cq_cleanup(struct rxe_pool_elem *arg);
/* rxe_mcast.c */
-void rxe_mc_cleanup(struct rxe_pool_elem *arg);
+struct rxe_mcg *rxe_lookup_mcg(struct rxe_dev *rxe, union ib_gid *mgid);
int rxe_attach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid);
int rxe_detach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid);
+void rxe_mc_cleanup(struct rxe_pool_elem *arg);
/* rxe_mmap.c */
struct rxe_mmap_info {
diff --git a/drivers/infiniband/sw/rxe/rxe_mcast.c b/drivers/infiniband/sw/rxe/rxe_mcast.c
index 62ace10206b0..4c3eb9c723b4 100644
--- a/drivers/infiniband/sw/rxe/rxe_mcast.c
+++ b/drivers/infiniband/sw/rxe/rxe_mcast.c
@@ -25,60 +25,172 @@ static int rxe_mcast_delete(struct rxe_dev *rxe, union ib_gid *mgid)
return dev_mc_del(rxe->ndev, ll_addr);
}
-/* caller should hold mc_grp_rxe->mcg_lock */
-static struct rxe_mcg *create_grp(struct rxe_dev *rxe,
- struct rxe_pool *pool,
- union ib_gid *mgid)
+/**
+ * __rxe_insert_mcg - insert an mcg into red-black tree (rxe->mcg_tree)
+ * @mcg: mcast group object with an embedded red-black tree node
+ *
+ * Context: caller must hold a reference to mcg and rxe->mcg_lock and
+ * is responsible to avoid adding the same mcg twice to the tree.
+ */
+static void __rxe_insert_mcg(struct rxe_mcg *mcg)
{
- int err;
+ struct rb_root *tree = &mcg->rxe->mcg_tree;
+ struct rb_node **link = &tree->rb_node;
+ struct rb_node *node = NULL;
+ struct rxe_mcg *tmp;
+ int cmp;
+
+ while (*link) {
+ node = *link;
+ tmp = rb_entry(node, struct rxe_mcg, node);
+
+ cmp = memcmp(&tmp->mgid, &mcg->mgid, sizeof(mcg->mgid));
+ if (cmp > 0)
+ link = &(*link)->rb_left;
+ else
+ link = &(*link)->rb_right;
+ }
+
+ rb_link_node(&mcg->node, node, link);
+ rb_insert_color(&mcg->node, tree);
+}
+
+/**
+ * __rxe_remove_mcg - remove an mcg from red-black tree holding lock
+ * @mcg: mcast group object with an embedded red-black tree node
+ *
+ * Context: caller must hold a reference to mcg and rxe->mcg_lock
+ */
+static void __rxe_remove_mcg(struct rxe_mcg *mcg)
+{
+ rb_erase(&mcg->node, &mcg->rxe->mcg_tree);
+}
+
+/**
+ * __rxe_lookup_mcg - lookup mcg in rxe->mcg_tree while holding lock
+ * @rxe: rxe device object
+ * @mgid: multicast IP address
+ *
+ * Context: caller must hold rxe->mcg_lock
+ * Returns: mcg on success and takes a ref to mcg else NULL
+ */
+static struct rxe_mcg *__rxe_lookup_mcg(struct rxe_dev *rxe,
+ union ib_gid *mgid)
+{
+ struct rb_root *tree = &rxe->mcg_tree;
struct rxe_mcg *mcg;
+ struct rb_node *node;
+ int cmp;
- mcg = rxe_alloc_locked(&rxe->mc_grp_pool);
- if (!mcg)
- return ERR_PTR(-ENOMEM);
- rxe_add_ref(mcg);
+ node = tree->rb_node;
- INIT_LIST_HEAD(&mcg->qp_list);
- mcg->rxe = rxe;
- rxe_add_key_locked(mcg, mgid);
+ while (node) {
+ mcg = rb_entry(node, struct rxe_mcg, node);
- err = rxe_mcast_add(rxe, mgid);
- if (unlikely(err)) {
- rxe_drop_key_locked(mcg);
- rxe_drop_ref(mcg);
- return ERR_PTR(err);
+ cmp = memcmp(&mcg->mgid, mgid, sizeof(*mgid));
+
+ if (cmp > 0)
+ node = node->rb_left;
+ else if (cmp < 0)
+ node = node->rb_right;
+ else
+ break;
}
- return mcg;
+ if (node) {
+ rxe_add_ref(mcg);
+ return mcg;
+ }
+
+ return NULL;
}
-static int rxe_mcast_get_grp(struct rxe_dev *rxe, union ib_gid *mgid,
- struct rxe_mcg **mcgp)
+/**
+ * rxe_lookup_mcg - lookup up mcg in red-back tree
+ * @rxe: rxe device object
+ * @mgid: multicast IP address
+ *
+ * Returns: mcg if found else NULL
+ */
+struct rxe_mcg *rxe_lookup_mcg(struct rxe_dev *rxe, union ib_gid *mgid)
{
- int err;
struct rxe_mcg *mcg;
+
+ spin_lock_bh(&rxe->mcg_lock);
+ mcg = __rxe_lookup_mcg(rxe, mgid);
+ spin_unlock_bh(&rxe->mcg_lock);
+
+ return mcg;
+}
+
+/**
+ * rxe_get_mcg - lookup or allocate a mcg
+ * @rxe: rxe device object
+ * @mgid: multicast IP address
+ * @mcgp: address of returned mcg value
+ *
+ * Adds one ref if mcg already exists else add a second reference
+ * which is dropped when qp_num goes to zero.
+ *
+ * Returns: 0 and sets *mcgp to mcg on success else an error
+ */
+static int rxe_get_mcg(struct rxe_dev *rxe, union ib_gid *mgid,
+ struct rxe_mcg **mcgp)
+{
+ struct rxe_mcg *mcg, *tmp;
+ int ret;
struct rxe_pool *pool = &rxe->mc_grp_pool;
- if (rxe->attr.max_mcast_qp_attach == 0)
+ if (rxe->attr.max_mcast_grp == 0)
return -EINVAL;
- spin_lock_bh(&rxe->mcg_lock);
+ /* check to see if mcg already exists */
+ mcg = rxe_lookup_mcg(rxe, mgid);
+ if (mcg) {
+ *mcgp = mcg;
+ return 0;
+ }
- mcg = rxe_pool_get_key_locked(pool, mgid);
- if (mcg)
- goto done;
+ /* speculative alloc of mcg without using GFP_ATOMIC */
+ mcg = rxe_alloc(pool);
+ if (!mcg)
+ return -ENOMEM;
- mcg = create_grp(rxe, pool, mgid);
- if (IS_ERR(mcg)) {
+ spin_lock_bh(&rxe->mcg_lock);
+ /* re-check to see if someone else just added it */
+ tmp = __rxe_lookup_mcg(rxe, mgid);
+ if (tmp) {
spin_unlock_bh(&rxe->mcg_lock);
- err = PTR_ERR(mcg);
- return err;
+ rxe_drop_ref(mcg);
+ mcg = tmp;
+ goto out;
}
-done:
+ if (atomic_inc_return(&rxe->mcg_num) > rxe->attr.max_mcast_grp)
+ goto err_dec;
+
+ ret = rxe_mcast_add(rxe, mgid);
+ if (ret)
+ goto err_out;
+
+ rxe_add_ref(mcg);
+ mcg->rxe = rxe;
+ memcpy(&mcg->mgid, mgid, sizeof(*mgid));
+ INIT_LIST_HEAD(&mcg->qp_list);
+ atomic_inc(&rxe->mcg_num);
+ __rxe_insert_mcg(mcg);
spin_unlock_bh(&rxe->mcg_lock);
+out:
*mcgp = mcg;
return 0;
+
+err_dec:
+ atomic_dec(&rxe->mcg_num);
+ ret = -ENOMEM;
+err_out:
+ spin_unlock_bh(&rxe->mcg_lock);
+ rxe_drop_ref(mcg);
+ return ret;
}
static int rxe_mcast_add_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
@@ -136,7 +248,7 @@ static int rxe_mcast_drop_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
struct rxe_mca *mca, *tmp;
int n;
- mcg = rxe_pool_get_key(&rxe->mc_grp_pool, mgid);
+ mcg = rxe_lookup_mcg(rxe, mgid);
if (!mcg)
goto err1;
@@ -151,14 +263,14 @@ static int rxe_mcast_drop_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
atomic_dec(&qp->mcg_num);
spin_unlock_bh(&rxe->mcg_lock);
- rxe_drop_ref(mcg); /* ref from get_key */
+ rxe_drop_ref(mcg);
kfree(mca);
return 0;
}
}
spin_unlock_bh(&rxe->mcg_lock);
- rxe_drop_ref(mcg); /* ref from get_key */
+ rxe_drop_ref(mcg);
err1:
return -EINVAL;
}
@@ -168,7 +280,10 @@ void rxe_mc_cleanup(struct rxe_pool_elem *elem)
struct rxe_mcg *mcg = container_of(elem, typeof(*mcg), elem);
struct rxe_dev *rxe = mcg->rxe;
- rxe_drop_key(mcg);
+ spin_lock_bh(&rxe->mcg_lock);
+ __rxe_remove_mcg(mcg);
+ spin_unlock_bh(&rxe->mcg_lock);
+
rxe_mcast_delete(rxe, &mcg->mgid);
}
@@ -180,7 +295,7 @@ int rxe_attach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid)
struct rxe_mcg *mcg;
/* takes a ref on mcg if successful */
- err = rxe_mcast_get_grp(rxe, mgid, &mcg);
+ err = rxe_get_mcg(rxe, mgid, &mcg);
if (err)
return err;
diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c
index 11246589fda7..f1ca83e09160 100644
--- a/drivers/infiniband/sw/rxe/rxe_recv.c
+++ b/drivers/infiniband/sw/rxe/rxe_recv.c
@@ -254,7 +254,7 @@ static void rxe_rcv_mcast_pkt(struct sk_buff *skb)
memcpy(&dgid, &ipv6_hdr(skb)->daddr, sizeof(dgid));
/* lookup mcast group corresponding to mgid, takes a ref */
- mcg = rxe_pool_get_key(&rxe->mc_grp_pool, &dgid);
+ mcg = rxe_lookup_mcg(rxe, &dgid);
if (!mcg)
goto drop; /* mcast group not registered */
@@ -320,7 +320,7 @@ static void rxe_rcv_mcast_pkt(struct sk_buff *skb)
kfree(qp_array);
- rxe_drop_ref(mcg); /* drop ref from rxe_pool_get_key. */
+ rxe_drop_ref(mcg);
if (likely(!skb))
return;
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index b72f8f09d984..ea2d9ff29744 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -353,6 +353,7 @@ struct rxe_mw {
struct rxe_mcg {
struct rxe_pool_elem elem;
+ struct rb_node node;
struct rxe_dev *rxe;
struct list_head qp_list;
atomic_t qp_num;
@@ -397,6 +398,8 @@ struct rxe_dev {
struct rxe_pool mc_grp_pool;
spinlock_t mcg_lock; /* guard multicast groups */
+ struct rb_root mcg_tree;
+ atomic_t mcg_num;
spinlock_t pending_lock; /* guard pending_mmaps */
struct list_head pending_mmaps;
--
2.32.0
