On 9/15/23 11:00, Prasurjya Rohan saikia - I73664 wrote:
> From: Prasurjya Rohan Saikia <prasurjya.rohansaikia@xxxxxxxxxxxxx>
>
> Add an algorithm to backoff the Tx Task when low memory scenario is
> triggered at firmware. During high data transfer from host, the firmware
> runs out of VMM memory, which is used to hold the frames from the host.
> So, adding the flow control delays the transmit from host side when
> there is not enough space to accommodate frames in firmware side.
>
> Signed-off-by: Prasurjya Rohan Saikia <prasurjya.rohansaikia@xxxxxxxxxxxxx>
Acked-by: Ajay Singh <ajay.kathat@xxxxxxxxxxxxx>
> ---
> v3 -> v4: As per review comments, replaced
> schedule_timeout_interruptible() by msleep_interruptible().
>
> v2 -> v3: Replaced schedule_timeout() by
> schedule_timeout_interruptible().
>
> v1 -> v2: Removed the unused `timeout` variable.
> ---
> .../net/wireless/microchip/wilc1000/netdev.c | 20 +++++++++++++++----
> .../net/wireless/microchip/wilc1000/netdev.h | 2 ++
> 2 files changed, 18 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.c b/drivers/net/wireless/microchip/wilc1000/netdev.c
> index e9f59de31b0b..91d71e0f7ef2 100644
> --- a/drivers/net/wireless/microchip/wilc1000/netdev.c
> +++ b/drivers/net/wireless/microchip/wilc1000/netdev.c
> @@ -148,8 +148,8 @@ static int wilc_txq_task(void *vp)
>
> complete(&wl->txq_thread_started);
> while (1) {
> - wait_for_completion(&wl->txq_event);
> -
> + if (wait_for_completion_interruptible(&wl->txq_event))
> + continue;
> if (wl->close) {
> complete(&wl->txq_thread_started);
>
> @@ -166,12 +166,24 @@ static int wilc_txq_task(void *vp)
> srcu_idx = srcu_read_lock(&wl->srcu);
> list_for_each_entry_rcu(ifc, &wl->vif_list,
> list) {
> - if (ifc->mac_opened && ifc->ndev)
> + if (ifc->mac_opened &&
> + netif_queue_stopped(ifc->ndev))
> netif_wake_queue(ifc->ndev);
> }
> srcu_read_unlock(&wl->srcu, srcu_idx);
> }
> - } while (ret == WILC_VMM_ENTRY_FULL_RETRY && !wl->close);
> + if (ret != WILC_VMM_ENTRY_FULL_RETRY)
> + break;
> + /* Back off TX task from sending packets for some time.
> + * msleep_interruptible will allow RX task to run and
> + * free buffers. TX task will be in TASK_INTERRUPTIBLE
> + * state which will put the thread back to CPU running
> + * queue when it's signaled even if the timeout isn't
> + * elapsed. This gives faster chance for reserved SK
> + * buffers to be free.
> + */
> + msleep_interruptible(TX_BACKOFF_WEIGHT_MS);
> + } while (!wl->close);
> }
> return 0;
> }
> diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.h b/drivers/net/wireless/microchip/wilc1000/netdev.h
> index bb1a315a7b7e..aafe3dc44ac6 100644
> --- a/drivers/net/wireless/microchip/wilc1000/netdev.h
> +++ b/drivers/net/wireless/microchip/wilc1000/netdev.h
> @@ -27,6 +27,8 @@
> #define TCP_ACK_FILTER_LINK_SPEED_THRESH 54
> #define DEFAULT_LINK_SPEED 72
>
> +#define TX_BACKOFF_WEIGHT_MS 1
> +
> struct wilc_wfi_stats {
> unsigned long rx_packets;
> unsigned long tx_packets;
