From: Jason Gunthorpe <jgg@mellanox.com>
Date: Mon, 19 Aug 2019 14:17:00 +0300
Subject: RDMA/odp: Iterate over the whole rbtree directly
Patch-mainline: v5.4-rc1
Git-commit: f993de88a55f2dd56f17248d06c0dfda9a9799db
References: jsc#SLE-8449

Instead of intersecting a full interval, just iterate over every element
directly. This is faster and clearer.

Link: https://lore.kernel.org/r/20190819111710.18440-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/core/umem_odp.c |   40 ++++++++++++++++++----------------
 drivers/infiniband/hw/mlx5/odp.c   |   43 +++++++++++++++++--------------------
 2 files changed, 41 insertions(+), 42 deletions(-)

--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -72,31 +72,34 @@ static void ib_umem_notifier_end_account
 	mutex_unlock(&umem_odp->umem_mutex);
 }
 
-static int ib_umem_notifier_release_trampoline(struct ib_umem_odp *umem_odp,
-					       u64 start, u64 end, void *cookie)
-{
-	/*
-	 * Increase the number of notifiers running, to
-	 * prevent any further fault handling on this MR.
-	 */
-	ib_umem_notifier_start_account(umem_odp);
-	complete_all(&umem_odp->notifier_completion);
-	umem_odp->umem.context->invalidate_range(
-		umem_odp, ib_umem_start(umem_odp), ib_umem_end(umem_odp));
-	return 0;
-}
-
 static void ib_umem_notifier_release(struct mmu_notifier *mn,
 				     struct mm_struct *mm)
 {
 	struct ib_ucontext_per_mm *per_mm =
 		container_of(mn, struct ib_ucontext_per_mm, mn);
+	struct rb_node *node;
 
 	down_read(&per_mm->umem_rwsem);
-	if (per_mm->active)
-		rbt_ib_umem_for_each_in_range(
-			&per_mm->umem_tree, 0, ULLONG_MAX,
-			ib_umem_notifier_release_trampoline, true, NULL);
+	if (!per_mm->active)
+		goto out;
+
+	for (node = rb_first_cached(&per_mm->umem_tree); node;
+	     node = rb_next(node)) {
+		struct ib_umem_odp *umem_odp =
+			rb_entry(node, struct ib_umem_odp, interval_tree.rb);
+
+		/*
+		 * Increase the number of notifiers running, to prevent any
+		 * further fault handling on this MR.
+		 */
+		ib_umem_notifier_start_account(umem_odp);
+		complete_all(&umem_odp->notifier_completion);
+		umem_odp->umem.context->invalidate_range(
+			umem_odp, ib_umem_start(umem_odp),
+			ib_umem_end(umem_odp));
+	}
+
+out:
 	up_read(&per_mm->umem_rwsem);
 }
 
@@ -756,4 +759,3 @@ int rbt_ib_umem_for_each_in_range(struct
 
 	return ret_val;
 }
-EXPORT_SYMBOL(rbt_ib_umem_for_each_in_range);
--- a/drivers/infiniband/hw/mlx5/odp.c
+++ b/drivers/infiniband/hw/mlx5/odp.c
@@ -541,34 +541,31 @@ struct mlx5_ib_mr *mlx5_ib_alloc_implici
 	return imr;
 }
 
-static int mr_leaf_free(struct ib_umem_odp *umem_odp, u64 start, u64 end,
-			void *cookie)
-{
-	struct mlx5_ib_mr *mr = umem_odp->private, *imr = cookie;
-
-	if (mr->parent != imr)
-		return 0;
-
-	ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem_odp),
-				    ib_umem_end(umem_odp));
-
-	if (umem_odp->dying)
-		return 0;
-
-	WRITE_ONCE(umem_odp->dying, 1);
-	atomic_inc(&imr->num_leaf_free);
-	schedule_work(&umem_odp->work);
-
-	return 0;
-}
-
 void mlx5_ib_free_implicit_mr(struct mlx5_ib_mr *imr)
 {
 	struct ib_ucontext_per_mm *per_mm = mr_to_per_mm(imr);
+	struct rb_node *node;
 
 	down_read(&per_mm->umem_rwsem);
-	rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, 0, ULLONG_MAX,
-				      mr_leaf_free, true, imr);
+	for (node = rb_first_cached(&per_mm->umem_tree); node;
+	     node = rb_next(node)) {
+		struct ib_umem_odp *umem_odp =
+			rb_entry(node, struct ib_umem_odp, interval_tree.rb);
+		struct mlx5_ib_mr *mr = umem_odp->private;
+
+		if (mr->parent != imr)
+			continue;
+
+		ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem_odp),
+					    ib_umem_end(umem_odp));
+
+		if (umem_odp->dying)
+			continue;
+
+		WRITE_ONCE(umem_odp->dying, 1);
+		atomic_inc(&imr->num_leaf_free);
+		schedule_work(&umem_odp->work);
+	}
 	up_read(&per_mm->umem_rwsem);
 
 	wait_event(imr->q_leaf_free, !atomic_read(&imr->num_leaf_free));