diff options
| author | Ben Hutchings <bhutchings@solarflare.com> | 2012-05-22 01:27:58 +0100 |
|---|---|---|
| committer | Ben Hutchings <bhutchings@solarflare.com> | 2012-08-24 19:00:27 +0100 |
| commit | 14bf718fb97efe9ff649c317e7d87a3617b13e7c (patch) | |
| tree | 421f6e0546d8d04ccad78292178c0fc560773a12 /drivers/net/ethernet/sfc/efx.c | |
| parent | 7668ff9c2ad7d354655e23afa836a92d54d2ea63 (diff) | |
| download | linux-14bf718fb97efe9ff649c317e7d87a3617b13e7c.tar.bz2 | |
sfc: Stop TX queues before they fill up
We now have a definite upper bound on the number of descriptors per
skb; use that to stop the queue when the next packet might not fit.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Diffstat (limited to 'drivers/net/ethernet/sfc/efx.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/efx.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index 65a8d49106a4..3b3f08489a5e 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -630,6 +630,16 @@ static void efx_start_datapath(struct efx_nic *efx) efx->rx_buffer_order = get_order(efx->rx_buffer_len + sizeof(struct efx_rx_page_state)); + /* We must keep at least one descriptor in a TX ring empty. + * We could avoid this when the queue size does not exactly + * match the hardware ring size, but it's not that important. + * Therefore we stop the queue when one more skb might fill + * the ring completely. We wake it when half way back to + * empty. + */ + efx->txq_stop_thresh = efx->txq_entries - efx_tx_max_skb_descs(efx); + efx->txq_wake_thresh = efx->txq_stop_thresh / 2; + /* Initialise the channels */ efx_for_each_channel(channel, efx) { efx_for_each_channel_tx_queue(tx_queue, channel) |