[PATCH 1/2] RDMA/pvrdma: Use bitmap_zalloc() when applicable

[PATCH 1/2] RDMA/pvrdma: Use bitmap_zalloc() when applicable

[Christophe JAILLET]

Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some
open-coded arithmetic in allocator arguments.

Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
consistency.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
index bf51357ea3aa..21ef3fb39915 100644
--- a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
+++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
@@ -63,7 +63,7 @@ int pvrdma_uar_table_init(struct pvrdma_dev *dev)
 	tbl->max = num;
 	tbl->mask = mask;
 	spin_lock_init(&tbl->lock);
-	tbl->table = kcalloc(BITS_TO_LONGS(num), sizeof(long), GFP_KERNEL);
+	tbl->table = bitmap_zalloc(num, GFP_KERNEL);
 	if (!tbl->table)
 		return -ENOMEM;
 
@@ -77,7 +77,7 @@ void pvrdma_uar_table_cleanup(struct pvrdma_dev *dev)
 {
 	struct pvrdma_id_table *tbl = &dev->uar_table.tbl;
 
-	kfree(tbl->table);
+	bitmap_free(tbl->table);
 }
 
 int pvrdma_uar_alloc(struct pvrdma_dev *dev, struct pvrdma_uar_map *uar)
-- 
2.30.2

[PATCH 2/2] RDMA/pvrdma: Use non-atomic bitmap functions when possible

[Christophe JAILLET]

In 'pvrdma_uar_table_init()', the 'tbl->table' bitmap has just been
allocated, so no concurrent accesses can occur.

The other accesses to the 'tbl->table' bitmap are protected by the
'tbl->lock' spinlock, so no concurrent accesses can happen.

So prefer the non-atomic '__[set|clear]_bit()' functions to save a few
cycles.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
index 21ef3fb39915..9a4de962e947 100644
--- a/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
+++ b/drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c
@@ -68,7 +68,7 @@ int pvrdma_uar_table_init(struct pvrdma_dev *dev)
 		return -ENOMEM;
 
 	/* 0th UAR is taken by the device. */
-	set_bit(0, tbl->table);
+	__set_bit(0, tbl->table);
 
 	return 0;
 }
@@ -100,7 +100,7 @@ int pvrdma_uar_alloc(struct pvrdma_dev *dev, struct pvrdma_uar_map *uar)
 		return -ENOMEM;
 	}
 
-	set_bit(obj, tbl->table);
+	__set_bit(obj, tbl->table);
 	obj |= tbl->top;
 
 	spin_unlock_irqrestore(&tbl->lock, flags);
@@ -120,7 +120,7 @@ void pvrdma_uar_free(struct pvrdma_dev *dev, struct pvrdma_uar_map *uar)
 
 	obj = uar->index & (tbl->max - 1);
 	spin_lock_irqsave(&tbl->lock, flags);
-	clear_bit(obj, tbl->table);
+	__clear_bit(obj, tbl->table);
 	tbl->last = min(tbl->last, obj);
 	tbl->top = (tbl->top + tbl->max) & tbl->mask;
 	spin_unlock_irqrestore(&tbl->lock, flags);
-- 
2.30.2

Re: [PATCH 1/2] RDMA/pvrdma: Use bitmap_zalloc() when applicable

[Jason Gunthorpe]

On Thu, Nov 25, 2021 at 09:05:40PM +0100, Christophe JAILLET wrote:
> Use 'bitmap_zalloc()' to simplify code, improve the semantic and avoid some
> open-coded arithmetic in allocator arguments.
> 
> Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
> consistency.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>  drivers/infiniband/hw/vmw_pvrdma/pvrdma_doorbell.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied to for-next, thanks

Jason