IB/mlx4: Convert rej_tmout radix-tree to XArray

Was missed during the initial review of the below patch

Fixes: 227a0e142e37 ("IB/mlx4: Add support for REJ due to timeout")
Link: https://lore.kernel.org/r/1602253482-6718-1-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/infiniband/hw/mlx4/cm.c b/drivers/infiniband/hw/mlx4/cm.c
index 0ce4b5a..4aff1c8 100644 (file)
--- a/drivers/infiniband/hw/mlx4/cm.c
+++ b/drivers/infiniband/hw/mlx4/cm.c
@@ -58,9 +58,7 @@ struct rej_tmout_entry {
        int slave;
        u32 rem_pv_cm_id;
        struct delayed_work timeout;
-       struct radix_tree_root *rej_tmout_root;
-       /* Points to the mutex protecting this radix-tree */
-       struct mutex *lock;
+       struct xarray *xa_rej_tmout;
 };
 
 struct cm_generic_msg {
@@ -350,9 +348,7 @@ static void rej_tmout_timeout(struct work_struct *work)
        struct rej_tmout_entry *item = container_of(delay, struct rej_tmout_entry, timeout);
        struct rej_tmout_entry *deleted;
 
-       mutex_lock(item->lock);
-       deleted = radix_tree_delete_item(item->rej_tmout_root, item->rem_pv_cm_id, NULL);
-       mutex_unlock(item->lock);
+       deleted = xa_cmpxchg(item->xa_rej_tmout, item->rem_pv_cm_id, item, NULL, 0);
 
        if (deleted != item)
                pr_debug("deleted(%p) != item(%p)\n", deleted, item);
@@ -363,18 +359,21 @@ static void rej_tmout_timeout(struct work_struct *work)
 static int alloc_rej_tmout(struct mlx4_ib_sriov *sriov, u32 rem_pv_cm_id, int slave)
 {
        struct rej_tmout_entry *item;
-       int sts;
+       struct rej_tmout_entry *old;
+       int ret = 0;
+
+       xa_lock(&sriov->xa_rej_tmout);
+       item = xa_load(&sriov->xa_rej_tmout, (unsigned long)rem_pv_cm_id);
 
-       mutex_lock(&sriov->rej_tmout_lock);
-       item = radix_tree_lookup(&sriov->rej_tmout_root, (unsigned long)rem_pv_cm_id);
-       mutex_unlock(&sriov->rej_tmout_lock);
        if (item) {
-               if (IS_ERR(item))
-                       return PTR_ERR(item);
-               /* If a retry, adjust delayed work */
-               mod_delayed_work(system_wq, &item->timeout, CM_CLEANUP_CACHE_TIMEOUT);
-               return 0;
+               if (xa_err(item))
+                       ret =  xa_err(item);
+               else
+                       /* If a retry, adjust delayed work */
+                       mod_delayed_work(system_wq, &item->timeout, CM_CLEANUP_CACHE_TIMEOUT);
+               goto err_or_exists;
        }
+       xa_unlock(&sriov->xa_rej_tmout);
 
        item = kmalloc(sizeof(*item), GFP_KERNEL);
        if (!item)
@@ -383,39 +382,44 @@ static int alloc_rej_tmout(struct mlx4_ib_sriov *sriov, u32 rem_pv_cm_id, int sl
        INIT_DELAYED_WORK(&item->timeout, rej_tmout_timeout);
        item->slave = slave;
        item->rem_pv_cm_id = rem_pv_cm_id;
-       item->rej_tmout_root = &sriov->rej_tmout_root;
-       item->lock = &sriov->rej_tmout_lock;
-
-       mutex_lock(&sriov->rej_tmout_lock);
-       sts = radix_tree_insert(&sriov->rej_tmout_root, (unsigned long)rem_pv_cm_id, item);
-       mutex_unlock(&sriov->rej_tmout_lock);
-       if (sts)
-               goto err_insert;
+       item->xa_rej_tmout = &sriov->xa_rej_tmout;
+
+       old = xa_cmpxchg(&sriov->xa_rej_tmout, (unsigned long)rem_pv_cm_id, NULL, item, GFP_KERNEL);
+       if (old) {
+               pr_debug(
+                       "Non-null old entry (%p) or error (%d) when inserting\n",
+                       old, xa_err(old));
+               kfree(item);
+               return xa_err(old);
+       }
 
        schedule_delayed_work(&item->timeout, CM_CLEANUP_CACHE_TIMEOUT);
 
        return 0;
 
-err_insert:
-       kfree(item);
-       return sts;
+err_or_exists:
+       xa_unlock(&sriov->xa_rej_tmout);
+       return ret;
 }
 
 static int lookup_rej_tmout_slave(struct mlx4_ib_sriov *sriov, u32 rem_pv_cm_id)
 {
        struct rej_tmout_entry *item;
+       int slave;
 
-       mutex_lock(&sriov->rej_tmout_lock);
-       item = radix_tree_lookup(&sriov->rej_tmout_root, (unsigned long)rem_pv_cm_id);
-       mutex_unlock(&sriov->rej_tmout_lock);
+       xa_lock(&sriov->xa_rej_tmout);
+       item = xa_load(&sriov->xa_rej_tmout, (unsigned long)rem_pv_cm_id);
 
-       if (!item || IS_ERR(item)) {
+       if (!item || xa_err(item)) {
                pr_debug("Could not find slave. rem_pv_cm_id 0x%x error: %d\n",
-                        rem_pv_cm_id, (int)PTR_ERR(item));
-               return !item ? -ENOENT : PTR_ERR(item);
+                        rem_pv_cm_id, xa_err(item));
+               slave = !item ? -ENOENT : xa_err(item);
+       } else {
+               slave = item->slave;
        }
+       xa_unlock(&sriov->xa_rej_tmout);
 
-       return item->slave;
+       return slave;
 }
 
 int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
@@ -483,34 +487,34 @@ void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
        INIT_LIST_HEAD(&dev->sriov.cm_list);
        dev->sriov.sl_id_map = RB_ROOT;
        xa_init_flags(&dev->sriov.pv_id_table, XA_FLAGS_ALLOC);
-       mutex_init(&dev->sriov.rej_tmout_lock);
-       INIT_RADIX_TREE(&dev->sriov.rej_tmout_root, GFP_KERNEL);
+       xa_init(&dev->sriov.xa_rej_tmout);
 }
 
-static void rej_tmout_tree_cleanup(struct mlx4_ib_sriov *sriov, int slave)
+static void rej_tmout_xa_cleanup(struct mlx4_ib_sriov *sriov, int slave)
 {
-       struct radix_tree_iter iter;
+       struct rej_tmout_entry *item;
        bool flush_needed = false;
-       __rcu void **slot;
+       unsigned long id;
        int cnt = 0;
 
-       mutex_lock(&sriov->rej_tmout_lock);
-       radix_tree_for_each_slot(slot, &sriov->rej_tmout_root, &iter, 0) {
-               struct rej_tmout_entry *item = *slot;
-
+       xa_lock(&sriov->xa_rej_tmout);
+       xa_for_each(&sriov->xa_rej_tmout, id, item) {
                if (slave < 0 || slave == item->slave) {
                        mod_delayed_work(system_wq, &item->timeout, 0);
                        flush_needed = true;
                        ++cnt;
                }
        }
-       mutex_unlock(&sriov->rej_tmout_lock);
+       xa_unlock(&sriov->xa_rej_tmout);
 
        if (flush_needed) {
                flush_scheduled_work();
-               pr_debug("Deleted %d entries in radix_tree for slave %d during cleanup\n",
-                        slave, cnt);
+               pr_debug("Deleted %d entries in xarray for slave %d during cleanup\n",
+                        cnt, slave);
        }
+
+       if (slave < 0)
+               WARN_ON(!xa_empty(&sriov->xa_rej_tmout));
 }
 
 /* slave = -1 ==> all slaves */
@@ -581,5 +585,5 @@ void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
                kfree(map);
        }
 
-       rej_tmout_tree_cleanup(sriov, slave);
+       rej_tmout_xa_cleanup(sriov, slave);
 }

diff --git a/drivers/infiniband/hw/mlx4/mlx4_ib.h b/drivers/infiniband/hw/mlx4/mlx4_ib.h
index 2f9b1a6..58df064 100644 (file)
--- a/drivers/infiniband/hw/mlx4/mlx4_ib.h
+++ b/drivers/infiniband/hw/mlx4/mlx4_ib.h
@@ -522,9 +522,7 @@ struct mlx4_ib_sriov {
        spinlock_t id_map_lock;
        struct rb_root sl_id_map;
        struct list_head cm_list;
-       /* Protects the radix-tree */
-       struct mutex rej_tmout_lock;
-       struct radix_tree_root rej_tmout_root;
+       struct xarray xa_rej_tmout;
 };
 
 struct gid_cache_context {