/* Size of buffer allocated for skb header area. */
#define EFX_SKB_HEADERS 64u
-/*
- * rx_alloc_method - RX buffer allocation method
- *
- * This driver supports two methods for allocating and using RX buffers:
- * each RX buffer may be backed by an skb or by an order-n page.
- *
- * When GRO is in use then the second method has a lower overhead,
- * since we don't have to allocate then free skbs on reassembled frames.
- *
- * Values:
- * - RX_ALLOC_METHOD_AUTO = 0
- * - RX_ALLOC_METHOD_SKB = 1
- * - RX_ALLOC_METHOD_PAGE = 2
- *
- * The heuristic for %RX_ALLOC_METHOD_AUTO is a simple hysteresis count
- * controlled by the parameters below.
- *
- * - Since pushing and popping descriptors are separated by the rx_queue
- * size, so the watermarks should be ~rxd_size.
- * - The performance win by using page-based allocation for GRO is less
- * than the performance hit of using page-based allocation of non-GRO,
- * so the watermarks should reflect this.
- *
- * Per channel we maintain a single variable, updated by each channel:
- *
- * rx_alloc_level += (gro_performed ? RX_ALLOC_FACTOR_GRO :
- * RX_ALLOC_FACTOR_SKB)
- * Per NAPI poll interval, we constrain rx_alloc_level to 0..MAX (which
- * limits the hysteresis), and update the allocation strategy:
- *
- * rx_alloc_method = (rx_alloc_level > RX_ALLOC_LEVEL_GRO ?
- * RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB)
- */
-static int rx_alloc_method = RX_ALLOC_METHOD_AUTO;
-
-#define RX_ALLOC_LEVEL_GRO 0x2000
-#define RX_ALLOC_LEVEL_MAX 0x3000
-#define RX_ALLOC_FACTOR_GRO 1
-#define RX_ALLOC_FACTOR_SKB (-2)
-
/* This is the percentage fill level below which new RX descriptors
* will be added to the RX descriptor ring.
*/
static u8 *efx_rx_buf_eh(struct efx_nic *efx, struct efx_rx_buffer *buf)
{
- if (buf->flags & EFX_RX_BUF_PAGE)
- return page_address(buf->u.page) + efx_rx_buf_offset(efx, buf);
- else
- return (u8 *)buf->u.skb->data + efx->type->rx_buffer_hash_size;
+ return page_address(buf->page) + efx_rx_buf_offset(efx, buf);
}
static inline u32 efx_rx_buf_hash(const u8 *eh)
}
/**
- * efx_init_rx_buffers_skb - create EFX_RX_BATCH skb-based RX buffers
- *
- * @rx_queue: Efx RX queue
- *
- * This allocates EFX_RX_BATCH skbs, maps them for DMA, and populates a
- * struct efx_rx_buffer for each one. Return a negative error code or 0
- * on success. May fail having only inserted fewer than EFX_RX_BATCH
- * buffers.
- */
-static int efx_init_rx_buffers_skb(struct efx_rx_queue *rx_queue)
-{
- struct efx_nic *efx = rx_queue->efx;
- struct net_device *net_dev = efx->net_dev;
- struct efx_rx_buffer *rx_buf;
- struct sk_buff *skb;
- int skb_len = efx->rx_buffer_len;
- unsigned index, count;
-
- for (count = 0; count < EFX_RX_BATCH; ++count) {
- index = rx_queue->added_count & rx_queue->ptr_mask;
- rx_buf = efx_rx_buffer(rx_queue, index);
-
- rx_buf->u.skb = skb = netdev_alloc_skb(net_dev, skb_len);
- if (unlikely(!skb))
- return -ENOMEM;
-
- /* Adjust the SKB for padding */
- skb_reserve(skb, NET_IP_ALIGN);
- rx_buf->len = skb_len - NET_IP_ALIGN;
- rx_buf->flags = 0;
-
- rx_buf->dma_addr = dma_map_single(&efx->pci_dev->dev,
- skb->data, rx_buf->len,
- DMA_FROM_DEVICE);
- if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
- rx_buf->dma_addr))) {
- dev_kfree_skb_any(skb);
- rx_buf->u.skb = NULL;
- return -EIO;
- }
-
- ++rx_queue->added_count;
- ++rx_queue->alloc_skb_count;
- }
-
- return 0;
-}
-
-/**
- * efx_init_rx_buffers_page - create EFX_RX_BATCH page-based RX buffers
+ * efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers
*
* @rx_queue: Efx RX queue
*
* code or 0 on success. If a single page can be split between two buffers,
* then the page will either be inserted fully, or not at at all.
*/
-static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
+static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
struct efx_rx_buffer *rx_buf;
index = rx_queue->added_count & rx_queue->ptr_mask;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
- rx_buf->u.page = page;
+ rx_buf->page = page;
rx_buf->page_offset = page_offset + EFX_PAGE_IP_ALIGN;
rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
- rx_buf->flags = EFX_RX_BUF_PAGE;
+ rx_buf->flags = 0;
++rx_queue->added_count;
- ++rx_queue->alloc_page_count;
++state->refcnt;
if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) {
struct efx_rx_buffer *rx_buf,
unsigned int used_len)
{
- if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
+ if (rx_buf->page) {
struct efx_rx_page_state *state;
- state = page_address(rx_buf->u.page);
+ state = page_address(rx_buf->page);
if (--state->refcnt == 0) {
dma_unmap_page(&efx->pci_dev->dev,
state->dma_addr,
rx_buf->dma_addr, used_len,
DMA_FROM_DEVICE);
}
- } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
- dma_unmap_single(&efx->pci_dev->dev, rx_buf->dma_addr,
- rx_buf->len, DMA_FROM_DEVICE);
}
}
static void efx_free_rx_buffer(struct efx_nic *efx,
struct efx_rx_buffer *rx_buf)
{
- if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
- __free_pages(rx_buf->u.page, efx->rx_buffer_order);
- rx_buf->u.page = NULL;
- } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
- dev_kfree_skb_any(rx_buf->u.skb);
- rx_buf->u.skb = NULL;
+ if (rx_buf->page) {
+ __free_pages(rx_buf->page, efx->rx_buffer_order);
+ rx_buf->page = NULL;
}
}
static void efx_resurrect_rx_buffer(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf)
{
- struct efx_rx_page_state *state = page_address(rx_buf->u.page);
+ struct efx_rx_page_state *state = page_address(rx_buf->page);
struct efx_rx_buffer *new_buf;
unsigned fill_level, index;
}
++state->refcnt;
- get_page(rx_buf->u.page);
+ get_page(rx_buf->page);
index = rx_queue->added_count & rx_queue->ptr_mask;
new_buf = efx_rx_buffer(rx_queue, index);
new_buf->dma_addr = rx_buf->dma_addr ^ (PAGE_SIZE >> 1);
- new_buf->u.page = rx_buf->u.page;
+ new_buf->page = rx_buf->page;
new_buf->len = rx_buf->len;
- new_buf->flags = EFX_RX_BUF_PAGE;
++rx_queue->added_count;
}
struct efx_rx_buffer *new_buf;
unsigned index;
- rx_buf->flags &= EFX_RX_BUF_PAGE;
+ rx_buf->flags = 0;
- if ((rx_buf->flags & EFX_RX_BUF_PAGE) &&
- efx->rx_buffer_len <= EFX_RX_HALF_PAGE &&
- page_count(rx_buf->u.page) == 1)
+ if (efx->rx_buffer_len <= EFX_RX_HALF_PAGE &&
+ page_count(rx_buf->page) == 1)
efx_resurrect_rx_buffer(rx_queue, rx_buf);
index = rx_queue->added_count & rx_queue->ptr_mask;
new_buf = efx_rx_buffer(rx_queue, index);
memcpy(new_buf, rx_buf, sizeof(*new_buf));
- rx_buf->u.page = NULL;
+ rx_buf->page = NULL;
++rx_queue->added_count;
}
*/
void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue)
{
- struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
unsigned fill_level;
int space, rc = 0;
netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
"RX queue %d fast-filling descriptor ring from"
- " level %d to level %d using %s allocation\n",
+ " level %d to level %d\n",
efx_rx_queue_index(rx_queue), fill_level,
- rx_queue->max_fill,
- channel->rx_alloc_push_pages ? "page" : "skb");
+ rx_queue->max_fill);
+
do {
- if (channel->rx_alloc_push_pages)
- rc = efx_init_rx_buffers_page(rx_queue);
- else
- rc = efx_init_rx_buffers_skb(rx_queue);
+ rc = efx_init_rx_buffers(rx_queue);
if (unlikely(rc)) {
/* Ensure that we don't leave the rx queue empty */
if (rx_queue->added_count == rx_queue->removed_count)
static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf,
- int len, bool *leak_packet)
+ int len)
{
struct efx_nic *efx = rx_queue->efx;
unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
"RX event (0x%x > 0x%x+0x%x). Leaking\n",
efx_rx_queue_index(rx_queue), len, max_len,
efx->type->rx_buffer_padding);
- /* If this buffer was skb-allocated, then the meta
- * data at the end of the skb will be trashed. So
- * we have no choice but to leak the fragment.
- */
- *leak_packet = !(rx_buf->flags & EFX_RX_BUF_PAGE);
efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
} else {
if (net_ratelimit())
{
struct napi_struct *napi = &channel->napi_str;
gro_result_t gro_result;
+ struct efx_nic *efx = channel->efx;
+ struct page *page = rx_buf->page;
+ struct sk_buff *skb;
- if (rx_buf->flags & EFX_RX_BUF_PAGE) {
- struct efx_nic *efx = channel->efx;
- struct page *page = rx_buf->u.page;
- struct sk_buff *skb;
-
- rx_buf->u.page = NULL;
+ rx_buf->page = NULL;
- skb = napi_get_frags(napi);
- if (!skb) {
- put_page(page);
- return;
- }
+ skb = napi_get_frags(napi);
+ if (!skb) {
+ put_page(page);
+ return;
+ }
- if (efx->net_dev->features & NETIF_F_RXHASH)
- skb->rxhash = efx_rx_buf_hash(eh);
+ if (efx->net_dev->features & NETIF_F_RXHASH)
+ skb->rxhash = efx_rx_buf_hash(eh);
- skb_fill_page_desc(skb, 0, page,
- efx_rx_buf_offset(efx, rx_buf), rx_buf->len);
+ skb_fill_page_desc(skb, 0, page,
+ efx_rx_buf_offset(efx, rx_buf), rx_buf->len);
- skb->len = rx_buf->len;
- skb->data_len = rx_buf->len;
- skb->truesize += rx_buf->len;
- skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
- CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
+ skb->len = rx_buf->len;
+ skb->data_len = rx_buf->len;
+ skb->truesize += rx_buf->len;
+ skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
+ CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
- skb_record_rx_queue(skb, channel->rx_queue.core_index);
+ skb_record_rx_queue(skb, channel->rx_queue.core_index);
gro_result = napi_gro_frags(napi);
- } else {
- struct sk_buff *skb = rx_buf->u.skb;
- EFX_BUG_ON_PARANOID(!(rx_buf->flags & EFX_RX_PKT_CSUMMED));
- rx_buf->u.skb = NULL;
- skb->ip_summed = CHECKSUM_UNNECESSARY;
+ if (gro_result != GRO_DROP)
+ channel->irq_mod_score += 2;
+}
- gro_result = napi_gro_receive(napi, skb);
- }
+/* Allocate and construct an SKB around a struct page.*/
+static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
+ struct efx_rx_buffer *rx_buf,
+ u8 *eh, int hdr_len)
+{
+ struct efx_nic *efx = channel->efx;
+ struct sk_buff *skb;
- if (gro_result == GRO_NORMAL) {
- channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
- } else if (gro_result != GRO_DROP) {
- channel->rx_alloc_level += RX_ALLOC_FACTOR_GRO;
- channel->irq_mod_score += 2;
+ /* Allocate an SKB to store the headers */
+ skb = netdev_alloc_skb(efx->net_dev, hdr_len + EFX_PAGE_SKB_ALIGN);
+ if (unlikely(skb == NULL))
+ return NULL;
+
+ EFX_BUG_ON_PARANOID(rx_buf->len < hdr_len);
+
+ skb_reserve(skb, EFX_PAGE_SKB_ALIGN);
+
+ skb->len = rx_buf->len;
+ skb->truesize = rx_buf->len + sizeof(struct sk_buff);
+ memcpy(skb->data, eh, hdr_len);
+ skb->tail += hdr_len;
+
+ /* Append the remaining page onto the frag list */
+ if (rx_buf->len > hdr_len) {
+ skb->data_len = skb->len - hdr_len;
+ skb_fill_page_desc(skb, 0, rx_buf->page,
+ efx_rx_buf_offset(efx, rx_buf) + hdr_len,
+ skb->data_len);
+ } else {
+ __free_pages(rx_buf->page, efx->rx_buffer_order);
+ skb->data_len = 0;
}
+
+ /* Ownership has transferred from the rx_buf to skb */
+ rx_buf->page = NULL;
+
+ /* Move past the ethernet header */
+ skb->protocol = eth_type_trans(skb, efx->net_dev);
+
+ return skb;
}
void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
struct efx_nic *efx = rx_queue->efx;
struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
struct efx_rx_buffer *rx_buf;
- bool leak_packet = false;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->flags |= flags;
rx_queue->removed_count++;
/* Validate the length encoded in the event vs the descriptor pushed */
- efx_rx_packet__check_len(rx_queue, rx_buf, len, &leak_packet);
+ efx_rx_packet__check_len(rx_queue, rx_buf, len);
netif_vdbg(efx, rx_status, efx->net_dev,
"RX queue %d received id %x at %llx+%x %s%s\n",
/* Discard packet, if instructed to do so */
if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
- if (unlikely(leak_packet))
- channel->n_skbuff_leaks++;
- else
- efx_recycle_rx_buffer(channel, rx_buf);
+ efx_recycle_rx_buffer(channel, rx_buf);
/* Don't hold off the previous receive */
rx_buf = NULL;
channel->rx_pkt = rx_buf;
}
-static void efx_rx_deliver(struct efx_channel *channel,
+static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
struct efx_rx_buffer *rx_buf)
{
struct sk_buff *skb;
+ u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS);
- /* We now own the SKB */
- skb = rx_buf->u.skb;
- rx_buf->u.skb = NULL;
+ skb = efx_rx_mk_skb(channel, rx_buf, eh, hdr_len);
+ if (unlikely(skb == NULL)) {
+ efx_free_rx_buffer(channel->efx, rx_buf);
+ return;
+ }
+ skb_record_rx_queue(skb, channel->rx_queue.core_index);
/* Set the SKB flags */
skb_checksum_none_assert(skb);
- /* Record the rx_queue */
- skb_record_rx_queue(skb, channel->rx_queue.core_index);
-
if (channel->type->receive_skb)
if (channel->type->receive_skb(channel, skb))
- goto handled;
+ return;
/* Pass the packet up */
netif_receive_skb(skb);
-
-handled:
- /* Update allocation strategy method */
- channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
}
/* Handle a received packet. Second half: Touches packet payload. */
return;
}
- if (!(rx_buf->flags & EFX_RX_BUF_PAGE)) {
- struct sk_buff *skb = rx_buf->u.skb;
-
- prefetch(skb_shinfo(skb));
-
- skb_reserve(skb, efx->type->rx_buffer_hash_size);
- skb_put(skb, rx_buf->len);
-
- if (efx->net_dev->features & NETIF_F_RXHASH)
- skb->rxhash = efx_rx_buf_hash(eh);
-
- /* Move past the ethernet header. rx_buf->data still points
- * at the ethernet header */
- skb->protocol = eth_type_trans(skb, efx->net_dev);
-
- skb_record_rx_queue(skb, channel->rx_queue.core_index);
- }
-
if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
- if (likely(rx_buf->flags & (EFX_RX_BUF_PAGE | EFX_RX_PKT_CSUMMED)) &&
- !channel->type->receive_skb)
+ if (!channel->type->receive_skb)
efx_rx_packet_gro(channel, rx_buf, eh);
else
- efx_rx_deliver(channel, rx_buf);
-}
-
-void efx_rx_strategy(struct efx_channel *channel)
-{
- enum efx_rx_alloc_method method = rx_alloc_method;
-
- if (channel->type->receive_skb) {
- channel->rx_alloc_push_pages = false;
- return;
- }
-
- /* Only makes sense to use page based allocation if GRO is enabled */
- if (!(channel->efx->net_dev->features & NETIF_F_GRO)) {
- method = RX_ALLOC_METHOD_SKB;
- } else if (method == RX_ALLOC_METHOD_AUTO) {
- /* Constrain the rx_alloc_level */
- if (channel->rx_alloc_level < 0)
- channel->rx_alloc_level = 0;
- else if (channel->rx_alloc_level > RX_ALLOC_LEVEL_MAX)
- channel->rx_alloc_level = RX_ALLOC_LEVEL_MAX;
-
- /* Decide on the allocation method */
- method = ((channel->rx_alloc_level > RX_ALLOC_LEVEL_GRO) ?
- RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB);
- }
-
- /* Push the option */
- channel->rx_alloc_push_pages = (method == RX_ALLOC_METHOD_PAGE);
+ efx_rx_deliver(channel, eh, rx_buf);
}
int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
}
-module_param(rx_alloc_method, int, 0644);
-MODULE_PARM_DESC(rx_alloc_method, "Allocation method used for RX buffers");
-
module_param(rx_refill_threshold, uint, 0444);
MODULE_PARM_DESC(rx_refill_threshold,
"RX descriptor ring refill threshold (%)");
projects / mirror_ubuntu-artful-kernel.git / commitdiff