[PATCH v2 09/35] infiniband: Use kmemdup rather than duplicating its implementation

[PATCH v2 09/35] infiniband: Use kmemdup rather than duplicating its implementation

[Fuqian Huang]

kmemdup is introduced to duplicate a region of memory in a neat way.
Rather than kmalloc/kzalloc + memcpy, which the programmer needs to
write the size twice (sometimes lead to mistakes), kmemdup improves
readability, leads to smaller code and also reduce the chances of mistakes.
Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
---
Changes in v2:
  - Fix a typo in commit message (memset -> memcpy)

 drivers/infiniband/hw/i40iw/i40iw_cm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 8233f5a4e623..84b3ff2687fb 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c
@@ -4276,11 +4276,11 @@ static void i40iw_qhash_ctrl(struct i40iw_device *iwdev,
 	/* if not found then add a child listener if interface is going up */
 	if (!ifup)
 		return;
-	child_listen_node = kzalloc(sizeof(*child_listen_node), GFP_ATOMIC);
+	child_listen_node = kmemdup(parent_listen_node,
+			sizeof(*child_listen_node), GFP_ATOMIC);
 	if (!child_listen_node)
 		return;
 	node_allocated = true;
-	memcpy(child_listen_node, parent_listen_node, sizeof(*child_listen_node));
 
 	memcpy(child_listen_node->loc_addr, ipaddr,  ipv4 ? 4 : 16);
 
-- 
2.11.0

Re: [PATCH v2 09/35] infiniband: Use kmemdup rather than duplicating its implementation

[Jason Gunthorpe]

On Thu, Jul 04, 2019 at 12:27:42AM +0800, Fuqian Huang wrote:
> kmemdup is introduced to duplicate a region of memory in a neat way.
> Rather than kmalloc/kzalloc + memcpy, which the programmer needs to
> write the size twice (sometimes lead to mistakes), kmemdup improves
> readability, leads to smaller code and also reduce the chances of mistakes.
> Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy.
> 
> Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
> ---
> Changes in v2:
>   - Fix a typo in commit message (memset -> memcpy)
> 
>  drivers/infiniband/hw/i40iw/i40iw_cm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied to rdma for-next

Thanks,
Jason