sfc: Maintain interrupt moderation values in ticks, not microseconds
This simplifies the implementation a lot.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 862e4832..30951fb 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -228,26 +228,20 @@
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 <
+ efx->irq_rx_moderation) {
+ channel->irq_moderation += 1;
+ falcon_set_int_moderation(channel);
+ }
}
-
- if (channel->irq_moderation != old_irq_moderation)
- falcon_set_int_moderation(channel);
-
channel->irq_count = 0;
channel->irq_mod_score = 0;
}
@@ -1220,22 +1214,33 @@
*
**************************************************************************/
+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;
}
/**************************************************************************