diff options
| author | Ben Hutchings <bhutchings@solarflare.com> | 2009-10-23 08:32:13 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-10-24 04:27:15 -0700 |
| commit | 0d86ebd815416efb4e95ca70c3b8e65b476c5f9f (patch) | |
| tree | d6ed53cfda8b1968119ea3ddf2a0b24e18211cfb /drivers/net/sfc/efx.c | |
| parent | 0484e0db7c4293d6202cff730ee359d8a7a6b085 (diff) | |
| download | lwn-0d86ebd815416efb4e95ca70c3b8e65b476c5f9f.tar.gz lwn-0d86ebd815416efb4e95ca70c3b8e65b476c5f9f.zip | |
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>
Diffstat (limited to 'drivers/net/sfc/efx.c')
| -rw-r--r-- | drivers/net/sfc/efx.c | 41 |
1 files changed, 23 insertions, 18 deletions
diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c index 862e4832f614..30951fb3d20f 100644 --- a/drivers/net/sfc/efx.c +++ b/drivers/net/sfc/efx.c @@ -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 < + 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 @@ 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; } /************************************************************************** |