diff options
author | Íñigo Huguet <ihuguet@redhat.com> | 2021-09-09 12:28:45 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-09-09 13:17:37 +0300 |
commit | 415446185b939dcdcd6a483e705c805ab961e54c (patch) | |
tree | 36b7b984b10d9042349c6b8b1128109dc1c5b402 /drivers/net/ethernet/sfc/tx.c | |
parent | 2a48d96fd58a666ae231c3dd6fe4a458798ac645 (diff) | |
download | linux-415446185b939dcdcd6a483e705c805ab961e54c.tar.xz |
sfc: fallback for lack of xdp tx queues
If there are not enough resources to allocate one TX queue per core for
XDP TX it was completely disabled.
This patch implements a fallback solution for sharing the available
queues using __netif_tx_lock for synchronization. In the normal case that
there is one TX queue per CPU, no locking is done, as it was before.
With this fallback solution, XDP TX will work in much more cases that
were failing, specially in machines with many CPUs. It's hard for XDP
users to know what features are supported across different NICs and
configurations, so they will benefit on having wider support.
Signed-off-by: Íñigo Huguet <ihuguet@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/sfc/tx.c')
-rw-r--r-- | drivers/net/ethernet/sfc/tx.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c index 0c6650d2e239..c7afd6cda902 100644 --- a/drivers/net/ethernet/sfc/tx.c +++ b/drivers/net/ethernet/sfc/tx.c @@ -430,21 +430,23 @@ int efx_xdp_tx_buffers(struct efx_nic *efx, int n, struct xdp_frame **xdpfs, int cpu; int i; - cpu = raw_smp_processor_id(); + if (unlikely(efx->xdp_txq_queues_mode == EFX_XDP_TX_QUEUES_DISABLED)) + return -EINVAL; + if (unlikely(n && !xdpfs)) + return -EINVAL; + if (unlikely(!n)) + return 0; - if (!efx->xdp_tx_queue_count || - unlikely(cpu >= efx->xdp_tx_queue_count)) + cpu = raw_smp_processor_id(); + if (unlikely(cpu >= efx->xdp_tx_queue_count)) return -EINVAL; tx_queue = efx->xdp_tx_queues[cpu]; if (unlikely(!tx_queue)) return -EINVAL; - if (unlikely(n && !xdpfs)) - return -EINVAL; - - if (!n) - return 0; + if (efx->xdp_txq_queues_mode != EFX_XDP_TX_QUEUES_DEDICATED) + HARD_TX_LOCK(efx->net_dev, tx_queue->core_txq, cpu); /* Check for available space. We should never need multiple * descriptors per frame. @@ -484,6 +486,9 @@ int efx_xdp_tx_buffers(struct efx_nic *efx, int n, struct xdp_frame **xdpfs, if (flush && i > 0) efx_nic_push_buffers(tx_queue); + if (efx->xdp_txq_queues_mode != EFX_XDP_TX_QUEUES_DEDICATED) + HARD_TX_UNLOCK(efx->net_dev, tx_queue->core_txq); + return i == 0 ? -EIO : i; } |