[PATCH 6.6 073/122] net: ena: Use tx_ring instead of xdp_ring for XDP channel TX

Greg Kroah-Hartman
2024-04-15T14:35:52Z

From: David Arinzon <darinzon@amazon.com>

[ Upstream commit 911a8c960110b03ed519ce43ea6c9990a0ee0ceb ]

When an XDP program is loaded the existing channels in the driver split
into two halves:
- The first half of the channels contain RX and TX rings, these queues
are used for receiving traffic and sending packets originating from
kernel.
- The second half of the channels contain only a TX ring. These queues
are used for sending packets that were redirected using XDP_TX
or XDP_REDIRECT.

Referring to the queues in the second half of the channels as "xdp_ring"
can be confusing and may give the impression that ENA has the capability
to generate an additional special queue.

This patch ensures that the xdp_ring field is exclusively used to
describe the XDP TX queue that a specific RX queue needs to utilize when
forwarding packets with XDP TX and XDP REDIRECT, preserving the
integrity of the xdp_ring field in ena_ring.

Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Link: https://lore.kernel.org/r/20240101190855.18739-6-darinzon@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 36a1ca01f045 ("net: ena: Set tx_info->xdpf value to NULL")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/amazon/ena/ena_netdev.c | 12 +-
drivers/net/ethernet/amazon/ena/ena_netdev.h | 1 -
drivers/net/ethernet/amazon/ena/ena_xdp.c | 111 +++++++++----------
drivers/net/ethernet/amazon/ena/ena_xdp.h | 2 +-
4 files changed, 61 insertions(+), 65 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 8868494929c78..b239e473d59fa 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -1753,8 +1753,8 @@ static void ena_del_napi_in_range(struct ena_adapter *adapter,
for (i = first_index; i < first_index + count; i++) {
netif_napi_del(&adapter->ena_napi[i].napi);

- WARN_ON(!ENA_IS_XDP_INDEX(adapter, i) &&
- adapter->ena_napi[i].xdp_ring);
+ WARN_ON(ENA_IS_XDP_INDEX(adapter, i) &&
+ adapter->ena_napi[i].rx_ring);
}
}

@@ -1769,12 +1769,10 @@ static void ena_init_napi_in_range(struct ena_adapter *adapter,
netif_napi_add(adapter->netdev, &napi->napi,
ENA_IS_XDP_INDEX(adapter, i) ? ena_xdp_io_poll : ena_io_poll);

- if (!ENA_IS_XDP_INDEX(adapter, i)) {
+ if (!ENA_IS_XDP_INDEX(adapter, i))
napi->rx_ring = &adapter->rx_ring[i];
- napi->tx_ring = &adapter->tx_ring[i];
- } else {
- napi->xdp_ring = &adapter->tx_ring[i];
- }
+
+ napi->tx_ring = &adapter->tx_ring[i];
napi->qid = i;
}
}
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index 236d1f859a783..b364febab011e 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -125,7 +125,6 @@ struct ena_napi {
struct napi_struct napi;
struct ena_ring *tx_ring;
struct ena_ring *rx_ring;
- struct ena_ring *xdp_ring;
u32 qid;
struct dim dim;
};
diff --git a/drivers/net/ethernet/amazon/ena/ena_xdp.c b/drivers/net/ethernet/amazon/ena/ena_xdp.c
index 42370fa027733..363e361cc5aa8 100644
--- a/drivers/net/ethernet/amazon/ena/ena_xdp.c
+++ b/drivers/net/ethernet/amazon/ena/ena_xdp.c
@@ -5,23 +5,23 @@

#include "ena_xdp.h"

-static int validate_xdp_req_id(struct ena_ring *xdp_ring, u16 req_id)
+static int validate_xdp_req_id(struct ena_ring *tx_ring, u16 req_id)
{
struct ena_tx_buffer *tx_info;

- tx_info = &xdp_ring->tx_buffer_info[req_id];
+ tx_info = &tx_ring->tx_buffer_info[req_id];
if (likely(tx_info->xdpf))
return 0;

- return handle_invalid_req_id(xdp_ring, req_id, tx_info, true);
+ return handle_invalid_req_id(tx_ring, req_id, tx_info, true);
}

-static int ena_xdp_tx_map_frame(struct ena_ring *xdp_ring,
+static int ena_xdp_tx_map_frame(struct ena_ring *tx_ring,
struct ena_tx_buffer *tx_info,
struct xdp_frame *xdpf,
struct ena_com_tx_ctx *ena_tx_ctx)
{
- struct ena_adapter *adapter = xdp_ring->adapter;
+ struct ena_adapter *adapter = tx_ring->adapter;
struct ena_com_buf *ena_buf;
int push_len = 0;
dma_addr_t dma;
@@ -32,9 +32,9 @@ static int ena_xdp_tx_map_frame(struct ena_ring *xdp_ring,
data = tx_info->xdpf->data;
size = tx_info->xdpf->len;

- if (xdp_ring->tx_mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) {
+ if (tx_ring->tx_mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV) {
/* Designate part of the packet for LLQ */
- push_len = min_t(u32, size, xdp_ring->tx_max_header_size);
+ push_len = min_t(u32, size, tx_ring->tx_max_header_size);

ena_tx_ctx->push_header = data;

@@ -45,11 +45,11 @@ static int ena_xdp_tx_map_frame(struct ena_ring *xdp_ring,
ena_tx_ctx->header_len = push_len;

if (size > 0) {
- dma = dma_map_single(xdp_ring->dev,
+ dma = dma_map_single(tx_ring->dev,
data,
size,
DMA_TO_DEVICE);
- if (unlikely(dma_mapping_error(xdp_ring->dev, dma)))
+ if (unlikely(dma_mapping_error(tx_ring->dev, dma)))
goto error_report_dma_error;

tx_info->map_linear_data = 0;
@@ -65,14 +65,14 @@ static int ena_xdp_tx_map_frame(struct ena_ring *xdp_ring,
return 0;

error_report_dma_error:
- ena_increase_stat(&xdp_ring->tx_stats.dma_mapping_err, 1,
- &xdp_ring->syncp);
+ ena_increase_stat(&tx_ring->tx_stats.dma_mapping_err, 1,
+ &tx_ring->syncp);
netif_warn(adapter, tx_queued, adapter->netdev, "Failed to map xdp buff\n");

return -EINVAL;
}

-int ena_xdp_xmit_frame(struct ena_ring *xdp_ring,
+int ena_xdp_xmit_frame(struct ena_ring *tx_ring,
struct ena_adapter *adapter,
struct xdp_frame *xdpf,
int flags)
@@ -82,19 +82,19 @@ int ena_xdp_xmit_frame(struct ena_ring *xdp_ring,
u16 next_to_use, req_id;
int rc;

- next_to_use = xdp_ring->next_to_use;
- req_id = xdp_ring->free_ids[next_to_use];
- tx_info = &xdp_ring->tx_buffer_info[req_id];
+ next_to_use = tx_ring->next_to_use;
+ req_id = tx_ring->free_ids[next_to_use];
+ tx_info = &tx_ring->tx_buffer_info[req_id];
tx_info->num_of_bufs = 0;

- rc = ena_xdp_tx_map_frame(xdp_ring, tx_info, xdpf, &ena_tx_ctx);
+ rc = ena_xdp_tx_map_frame(tx_ring, tx_info, xdpf, &ena_tx_ctx);
if (unlikely(rc))
return rc;

ena_tx_ctx.req_id = req_id;

rc = ena_xmit_common(adapter,
- xdp_ring,
+ tx_ring,
tx_info,
&ena_tx_ctx,
next_to_use,
@@ -106,12 +106,12 @@ int ena_xdp_xmit_frame(struct ena_ring *xdp_ring,
* calls a memory barrier inside it.
*/
if (flags & XDP_XMIT_FLUSH)
- ena_ring_tx_doorbell(xdp_ring);
+ ena_ring_tx_doorbell(tx_ring);

return rc;

error_unmap_dma:
- ena_unmap_tx_buff(xdp_ring, tx_info);
+ ena_unmap_tx_buff(tx_ring, tx_info);
tx_info->xdpf = NULL;
return rc;
}
@@ -120,7 +120,7 @@ int ena_xdp_xmit(struct net_device *dev, int n,
struct xdp_frame **frames, u32 flags)
{
struct ena_adapter *adapter = netdev_priv(dev);
- struct ena_ring *xdp_ring;
+ struct ena_ring *tx_ring;
int qid, i, nxmit = 0;

if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
@@ -135,22 +135,22 @@ int ena_xdp_xmit(struct net_device *dev, int n,

qid = smp_processor_id() % adapter->xdp_num_queues;
qid += adapter->xdp_first_ring;
- xdp_ring = &adapter->tx_ring[qid];
+ tx_ring = &adapter->tx_ring[qid];

/* Other CPU ids might try to send thorugh this queue */
- spin_lock(&xdp_ring->xdp_tx_lock);
+ spin_lock(&tx_ring->xdp_tx_lock);

for (i = 0; i < n; i++) {
- if (ena_xdp_xmit_frame(xdp_ring, adapter, frames[i], 0))
+ if (ena_xdp_xmit_frame(tx_ring, adapter, frames[i], 0))
break;
nxmit++;
}

/* Ring doorbell to make device aware of the packets */
if (flags & XDP_XMIT_FLUSH)
- ena_ring_tx_doorbell(xdp_ring);
+ ena_ring_tx_doorbell(tx_ring);

- spin_unlock(&xdp_ring->xdp_tx_lock);
+ spin_unlock(&tx_ring->xdp_tx_lock);

/* Return number of packets sent */
return nxmit;
@@ -355,7 +355,7 @@ int ena_xdp(struct net_device *netdev, struct netdev_bpf *bpf)
return 0;
}

-static int ena_clean_xdp_irq(struct ena_ring *xdp_ring, u32 budget)
+static int ena_clean_xdp_irq(struct ena_ring *tx_ring, u32 budget)
{
u32 total_done = 0;
u16 next_to_clean;
@@ -363,55 +363,54 @@ static int ena_clean_xdp_irq(struct ena_ring *xdp_ring, u32 budget)
u16 req_id;
int rc;

- if (unlikely(!xdp_ring))
+ if (unlikely(!tx_ring))
return 0;
- next_to_clean = xdp_ring->next_to_clean;
+ next_to_clean = tx_ring->next_to_clean;

while (tx_pkts < budget) {
struct ena_tx_buffer *tx_info;
struct xdp_frame *xdpf;

- rc = ena_com_tx_comp_req_id_get(xdp_ring->ena_com_io_cq,
+ rc = ena_com_tx_comp_req_id_get(tx_ring->ena_com_io_cq,
&req_id);
if (rc) {
if (unlikely(rc == -EINVAL))
- handle_invalid_req_id(xdp_ring, req_id, NULL,
- true);
+ handle_invalid_req_id(tx_ring, req_id, NULL, true);
break;
}

/* validate that the request id points to a valid xdp_frame */
- rc = validate_xdp_req_id(xdp_ring, req_id);
+ rc = validate_xdp_req_id(tx_ring, req_id);
if (rc)
break;

- tx_info = &xdp_ring->tx_buffer_info[req_id];
+ tx_info = &tx_ring->tx_buffer_info[req_id];
xdpf = tx_info->xdpf;

tx_info->xdpf = NULL;
tx_info->last_jiffies = 0;
- ena_unmap_tx_buff(xdp_ring, tx_info);
+ ena_unmap_tx_buff(tx_ring, tx_info);

- netif_dbg(xdp_ring->adapter, tx_done, xdp_ring->netdev,
- "tx_poll: q %d skb %p completed\n", xdp_ring->qid,
+ netif_dbg(tx_ring->adapter, tx_done, tx_ring->netdev,
+ "tx_poll: q %d skb %p completed\n", tx_ring->qid,
xdpf);

tx_pkts++;
total_done += tx_info->tx_descs;

xdp_return_frame(xdpf);
- xdp_ring->free_ids[next_to_clean] = req_id;
+ tx_ring->free_ids[next_to_clean] = req_id;
next_to_clean = ENA_TX_RING_IDX_NEXT(next_to_clean,
- xdp_ring->ring_size);
+ tx_ring->ring_size);
}

- xdp_ring->next_to_clean = next_to_clean;
- ena_com_comp_ack(xdp_ring->ena_com_io_sq, total_done);
- ena_com_update_dev_comp_head(xdp_ring->ena_com_io_cq);
+ tx_ring->next_to_clean = next_to_clean;
+ ena_com_comp_ack(tx_ring->ena_com_io_sq, total_done);
+ ena_com_update_dev_comp_head(tx_ring->ena_com_io_cq);

- netif_dbg(xdp_ring->adapter, tx_done, xdp_ring->netdev,
+ netif_dbg(tx_ring->adapter, tx_done, tx_ring->netdev,
"tx_poll: q %d done. total pkts: %d\n",
- xdp_ring->qid, tx_pkts);
+ tx_ring->qid, tx_pkts);

return tx_pkts;
}
@@ -423,43 +422,43 @@ int ena_xdp_io_poll(struct napi_struct *napi, int budget)
{
struct ena_napi *ena_napi = container_of(napi, struct ena_napi, napi);
u32 xdp_work_done, xdp_budget;
- struct ena_ring *xdp_ring;
+ struct ena_ring *tx_ring;
int napi_comp_call = 0;
int ret;

- xdp_ring = ena_napi->xdp_ring;
+ tx_ring = ena_napi->tx_ring;

xdp_budget = budget;

- if (!test_bit(ENA_FLAG_DEV_UP, &xdp_ring->adapter->flags) ||
- test_bit(ENA_FLAG_TRIGGER_RESET, &xdp_ring->adapter->flags)) {
+ if (!test_bit(ENA_FLAG_DEV_UP, &tx_ring->adapter->flags) ||
+ test_bit(ENA_FLAG_TRIGGER_RESET, &tx_ring->adapter->flags)) {
napi_complete_done(napi, 0);
return 0;
}

- xdp_work_done = ena_clean_xdp_irq(xdp_ring, xdp_budget);
+ xdp_work_done = ena_clean_xdp_irq(tx_ring, xdp_budget);

/* If the device is about to reset or down, avoid unmask
* the interrupt and return 0 so NAPI won't reschedule
*/
- if (unlikely(!test_bit(ENA_FLAG_DEV_UP, &xdp_ring->adapter->flags))) {
+ if (unlikely(!test_bit(ENA_FLAG_DEV_UP, &tx_ring->adapter->flags))) {
napi_complete_done(napi, 0);
ret = 0;
} else if (xdp_budget > xdp_work_done) {
napi_comp_call = 1;
if (napi_complete_done(napi, xdp_work_done))
- ena_unmask_interrupt(xdp_ring, NULL);
- ena_update_ring_numa_node(xdp_ring, NULL);
+ ena_unmask_interrupt(tx_ring, NULL);
+ ena_update_ring_numa_node(tx_ring, NULL);
ret = xdp_work_done;
} else {
ret = xdp_budget;
}

- u64_stats_update_begin(&xdp_ring->syncp);
- xdp_ring->tx_stats.napi_comp += napi_comp_call;
- xdp_ring->tx_stats.tx_poll++;
- u64_stats_update_end(&xdp_ring->syncp);
- xdp_ring->tx_stats.last_napi_jiffies = jiffies;
+ u64_stats_update_begin(&tx_ring->syncp);
+ tx_ring->tx_stats.napi_comp += napi_comp_call;
+ tx_ring->tx_stats.tx_poll++;
+ u64_stats_update_end(&tx_ring->syncp);
+ tx_ring->tx_stats.last_napi_jiffies = jiffies;

return ret;
}
diff --git a/drivers/net/ethernet/amazon/ena/ena_xdp.h b/drivers/net/ethernet/amazon/ena/ena_xdp.h
index 6e472ba6ce1ba..3fa8e80b18a9e 100644
--- a/drivers/net/ethernet/amazon/ena/ena_xdp.h
+++ b/drivers/net/ethernet/amazon/ena/ena_xdp.h
@@ -35,7 +35,7 @@ void ena_xdp_exchange_program_rx_in_range(struct ena_adapter *adapter,
struct bpf_prog *prog,
int first, int count);
int ena_xdp_io_poll(struct napi_struct *napi, int budget);
-int ena_xdp_xmit_frame(struct ena_ring *xdp_ring,
+int ena_xdp_xmit_frame(struct ena_ring *tx_ring,
struct ena_adapter *adapter,
struct xdp_frame *xdpf,
int flags);
--
2.43.0