Hi Vipul,
> -----Original Message-----
> From: Vipul Ashri <vipul.as...@oracle.com>
> Sent: Wednesday, August 12, 2020 5:23 PM
> To: dev@dpdk.org
> Cc: Xia, Chenbo <chenbo....@intel.com>; vipul.as...@oracle.com;
> edwin.le...@oracle.com
> Subject: [PATCH v2] Fixes: 57f90f894588("net/virtio: reuse packed ring
> functions")
>
> Problem - Standard Tx packets are not going out and found broken
> due to cleanup malfunctioning whereever below mentioned macro is
> used.
>
> RootCause - Here inside Macro 'ASSIGN_UNLESS_EQUAL(var, val)'
> assignment to 'var' argument passed is always failing as assignment
> done using 'var_' having local scope only.
>
> Signed-off-by: Vipul Ashri <vipul.as...@oracle.com>
I understand now. Your patch makes sense. But your commit title/msg is still
wrong. An example commit message should be (you could use this):
net/virtio: fix wrong variable assignment in helper macro
Inside Macro ASSIGN_UNLESS_EQUAL(var, val), assignment to var is always failing
as assignment done using var_ having local scope only. This leads to TX packets
not going out and found broken due to cleanup malfunctioning. This patch fixes
the wrong variable assignment.
Fixes: 57f90f894588("net/virtio: reuse packed ring functions")
Cc: sta...@dpdk.org
Signed-off-by: Vipul Ashri <vipul.as...@oracle.com>
> ---
> drivers/net/virtio/virtqueue.h | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/virtio/virtqueue.h
> b/drivers/net/virtio/virtqueue.h
> index 105a9c00c..20c95471e 100644
> --- a/drivers/net/virtio/virtqueue.h
> +++ b/drivers/net/virtio/virtqueue.h
> @@ -607,10 +607,8 @@ virtqueue_notify(struct virtqueue *vq)
>
> /* avoid write operation when necessary, to lessen cache issues */
> #define ASSIGN_UNLESS_EQUAL(var, val) do { \
> - typeof(var) var_ = (var); \
> - typeof(val) val_ = (val); \
> - if ((var_) != (val_)) \
> - (var_) = (val_); \
> + if ((var) != (val)) \
> + (var) = (val); \
> } while (0)
>
> #define virtqueue_clear_net_hdr(hdr) do { \
> --
> 2.28.0.windows.1
