Commit 0d86ebd8 authored by Ben Hutchings's avatar Ben Hutchings Committed by David S. Miller
Browse files

sfc: Maintain interrupt moderation values in ticks, not microseconds 



This simplifies the implementation a lot.

Signed-off-by: default avatarBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 0484e0db

drivers/net/sfc/efx.c

+23 −18
Original line number Diff line number Diff line
@@ -228,26 +228,20 @@ static int efx_poll(struct napi_struct *napi, int budget) 
		if (channel->used_flags & EFX_USED_BY_RX &&

		    efx->irq_rx_adaptive &&

		    unlikely(++channel->irq_count == 1000)) {

			unsigned old_irq_moderation = channel->irq_moderation;



			if (unlikely(channel->irq_mod_score <

				     irq_adapt_low_thresh)) {

				channel->irq_moderation =

					max_t(int,

					      channel->irq_moderation -

					      FALCON_IRQ_MOD_RESOLUTION,

					      FALCON_IRQ_MOD_RESOLUTION);

				if (channel->irq_moderation > 1) {

					channel->irq_moderation -= 1;

					falcon_set_int_moderation(channel);

				}

			} else if (unlikely(channel->irq_mod_score >

					    irq_adapt_high_thresh)) {

				channel->irq_moderation =

					min(channel->irq_moderation +

					    FALCON_IRQ_MOD_RESOLUTION,

					    efx->irq_rx_moderation);

			}



			if (channel->irq_moderation != old_irq_moderation)

				if (channel->irq_moderation <

				    efx->irq_rx_moderation) {

					channel->irq_moderation += 1;

					falcon_set_int_moderation(channel);



				}

			}

			channel->irq_count = 0;

			channel->irq_mod_score = 0;

		}
@@ -1220,22 +1214,33 @@ void efx_flush_queues(struct efx_nic *efx) 
 *

 **************************************************************************/



static unsigned irq_mod_ticks(int usecs, int resolution)

{

	if (usecs <= 0)

		return 0; /* cannot receive interrupts ahead of time :-) */

	if (usecs < resolution)

		return 1; /* never round down to 0 */

	return usecs / resolution;

}



/* Set interrupt moderation parameters */

void efx_init_irq_moderation(struct efx_nic *efx, int tx_usecs, int rx_usecs,

			     bool rx_adaptive)

{

	struct efx_tx_queue *tx_queue;

	struct efx_rx_queue *rx_queue;

	unsigned tx_ticks = irq_mod_ticks(tx_usecs, FALCON_IRQ_MOD_RESOLUTION);

	unsigned rx_ticks = irq_mod_ticks(rx_usecs, FALCON_IRQ_MOD_RESOLUTION);



	EFX_ASSERT_RESET_SERIALISED(efx);



	efx_for_each_tx_queue(tx_queue, efx)

		tx_queue->channel->irq_moderation = tx_usecs;

		tx_queue->channel->irq_moderation = tx_ticks;



	efx->irq_rx_adaptive = rx_adaptive;

	efx->irq_rx_moderation = rx_usecs;

	efx->irq_rx_moderation = rx_ticks;

	efx_for_each_rx_queue(rx_queue, efx)

		rx_queue->channel->irq_moderation = rx_usecs;

		rx_queue->channel->irq_moderation = rx_ticks;

}



/**************************************************************************

drivers/net/sfc/ethtool.c

+3 −5
Original line number Diff line number Diff line
@@ -618,6 +618,9 @@ static int efx_ethtool_get_coalesce(struct net_device *net_dev, 
	coalesce->use_adaptive_rx_coalesce = efx->irq_rx_adaptive;

	coalesce->rx_coalesce_usecs_irq = efx->irq_rx_moderation;



	coalesce->tx_coalesce_usecs_irq *= FALCON_IRQ_MOD_RESOLUTION;

	coalesce->rx_coalesce_usecs_irq *= FALCON_IRQ_MOD_RESOLUTION;



	return 0;

}
@@ -656,11 +659,6 @@ static int efx_ethtool_set_coalesce(struct net_device *net_dev, 
	}



	efx_init_irq_moderation(efx, tx_usecs, rx_usecs, adaptive);



	/* Reset channel to pick up new moderation value.  Note that

	 * this may change the value of the irq_moderation field

	 * (e.g. to allow for hardware timer granularity).

	 */

	efx_for_each_channel(channel, efx)

		falcon_set_int_moderation(channel);

drivers/net/sfc/falcon.c

+1 −10
Original line number Diff line number Diff line
@@ -1063,20 +1063,11 @@ void falcon_set_int_moderation(struct efx_channel *channel) 


	/* Set timer register */

	if (channel->irq_moderation) {

		/* Round to resolution supported by hardware.  The value we

		 * program is based at 0.  So actual interrupt moderation

		 * achieved is ((x + 1) * res).

		 */

		channel->irq_moderation -= (channel->irq_moderation %

					    FALCON_IRQ_MOD_RESOLUTION);

		if (channel->irq_moderation < FALCON_IRQ_MOD_RESOLUTION)

			channel->irq_moderation = FALCON_IRQ_MOD_RESOLUTION;

		EFX_POPULATE_DWORD_2(timer_cmd,

				     FRF_AB_TC_TIMER_MODE,

				     FFE_BB_TIMER_MODE_INT_HLDOFF,

				     FRF_AB_TC_TIMER_VAL,

				     channel->irq_moderation /

				     FALCON_IRQ_MOD_RESOLUTION - 1);

				     channel->irq_moderation - 1);

	} else {

		EFX_POPULATE_DWORD_2(timer_cmd,

				     FRF_AB_TC_TIMER_MODE,

drivers/net/sfc/net_driver.h

+1 −1
Original line number Diff line number Diff line
@@ -327,7 +327,7 @@ enum efx_rx_alloc_method { 
 * @used_flags: Channel is used by net driver

 * @enabled: Channel enabled indicator

 * @irq: IRQ number (MSI and MSI-X only)

 * @irq_moderation: IRQ moderation value (in us)

 * @irq_moderation: IRQ moderation value (in hardware ticks)

 * @napi_dev: Net device used with NAPI

 * @napi_str: NAPI control structure

 * @reset_work: Scheduled reset work thread