[PATCH net] ibmveth: Reduce maximum tx queues to 8

[PATCH net] ibmveth: Reduce maximum tx queues to 8

[Nick Child]

Previously, the maximum number of transmit queues
allowed was 16. Due to resource concerns, limit
to 8 queues instead.

Since the driver is virtualized away from the
physical NIC, the purpose of multiple queues is
purely to allow for parallel calls to the
hypervisor. Therefore, there is no noticeable
effect on performance by reducing queue count to 8.

Reported-by: Reported-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Nick Child <nnac123@linux.ibm.com>
---
Relevant links:
 - Introduce multiple tx queues (accepted in v6.1):
   https://lore.kernel.org/netdev/20220928214350.29795-2-nnac123@linux.ibm.com/
 - Resource concerns with 16 queues:
   https://lore.kernel.org/netdev/CAA93jw5reJmaOvt9vw15C1fo1AN7q5jVKzUocbAoNDC-cpi=KQ@mail.gmail.com/

 drivers/net/ethernet/ibm/ibmveth.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ibm/ibmveth.h b/drivers/net/ethernet/ibm/ibmveth.h
index 4f8357187292..6b5faf1feb0b 100644
--- a/drivers/net/ethernet/ibm/ibmveth.h
+++ b/drivers/net/ethernet/ibm/ibmveth.h
@@ -99,7 +99,7 @@ static inline long h_illan_attributes(unsigned long unit_address,
 #define IBMVETH_FILT_LIST_SIZE 4096
 #define IBMVETH_MAX_BUF_SIZE (1024 * 128)
 #define IBMVETH_MAX_TX_BUF_SIZE (1024 * 64)
-#define IBMVETH_MAX_QUEUES 16U
+#define IBMVETH_MAX_QUEUES 8U
 
 static int pool_size[] = { 512, 1024 * 2, 1024 * 16, 1024 * 32, 1024 * 64 };
 static int pool_count[] = { 256, 512, 256, 256, 256 };
-- 
2.31.1

Re: [PATCH net] ibmveth: Reduce maximum tx queues to 8

[Leon Romanovsky]

On Wed, Nov 02, 2022 at 10:30:40AM -0500, Nick Child wrote:
> Previously, the maximum number of transmit queues
> allowed was 16. Due to resource concerns, limit
> to 8 queues instead.
> 
> Since the driver is virtualized away from the
> physical NIC, the purpose of multiple queues is
> purely to allow for parallel calls to the
> hypervisor. Therefore, there is no noticeable
> effect on performance by reducing queue count to 8.

Very odd typography of this commit message. You have upto 80 chars in
one line, use them.

> 
> Reported-by: Reported-by: Dave Taht <dave.taht@gmail.com>

Double Reported-by.

> Signed-off-by: Nick Child <nnac123@linux.ibm.com>

And missing Fixes line for "net".

> ---
> Relevant links:
>  - Introduce multiple tx queues (accepted in v6.1):
>    https://lore.kernel.org/netdev/20220928214350.29795-2-nnac123@linux.ibm.com/
>  - Resource concerns with 16 queues:
>    https://lore.kernel.org/netdev/CAA93jw5reJmaOvt9vw15C1fo1AN7q5jVKzUocbAoNDC-cpi=KQ@mail.gmail.com/
> 
>  drivers/net/ethernet/ibm/ibmveth.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/ibm/ibmveth.h b/drivers/net/ethernet/ibm/ibmveth.h
> index 4f8357187292..6b5faf1feb0b 100644
> --- a/drivers/net/ethernet/ibm/ibmveth.h
> +++ b/drivers/net/ethernet/ibm/ibmveth.h
> @@ -99,7 +99,7 @@ static inline long h_illan_attributes(unsigned long unit_address,
>  #define IBMVETH_FILT_LIST_SIZE 4096
>  #define IBMVETH_MAX_BUF_SIZE (1024 * 128)
>  #define IBMVETH_MAX_TX_BUF_SIZE (1024 * 64)
> -#define IBMVETH_MAX_QUEUES 16U
> +#define IBMVETH_MAX_QUEUES 8U
>  
>  static int pool_size[] = { 512, 1024 * 2, 1024 * 16, 1024 * 32, 1024 * 64 };
>  static int pool_count[] = { 256, 512, 256, 256, 256 };
> -- 
> 2.31.1
>