diff options
Diffstat (limited to 'drivers/net/ethernet/sfc/rx.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/rx.c | 793 |
1 files changed, 410 insertions, 383 deletions
diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c index bb579a6..e73e30b 100644 --- a/drivers/net/ethernet/sfc/rx.c +++ b/drivers/net/ethernet/sfc/rx.c @@ -16,6 +16,7 @@ #include <linux/udp.h> #include <linux/prefetch.h> #include <linux/moduleparam.h> +#include <linux/iommu.h> #include <net/ip.h> #include <net/checksum.h> #include "net_driver.h" @@ -24,85 +25,39 @@ #include "selftest.h" #include "workarounds.h" -/* Number of RX descriptors pushed at once. */ -#define EFX_RX_BATCH 8 +/* Preferred number of descriptors to fill at once */ +#define EFX_RX_PREFERRED_BATCH 8U -/* Maximum size of a buffer sharing a page */ -#define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state)) +/* Number of RX buffers to recycle pages for. When creating the RX page recycle + * ring, this number is divided by the number of buffers per page to calculate + * the number of pages to store in the RX page recycle ring. + */ +#define EFX_RECYCLE_RING_SIZE_IOMMU 4096 +#define EFX_RECYCLE_RING_SIZE_NOIOMMU (2 * EFX_RX_PREFERRED_BATCH) /* 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 unsigned int rx_refill_threshold; +/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */ +#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \ + EFX_RX_USR_BUF_SIZE) + /* * RX maximum head room required. * - * This must be at least 1 to prevent overflow and at least 2 to allow - * pipelined receives. + * This must be at least 1 to prevent overflow, plus one packet-worth + * to allow pipelined receives. */ -#define EFX_RXD_HEAD_ROOM 2 +#define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS) -/* Offset of ethernet header within page */ -static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx, - struct efx_rx_buffer *buf) +static inline u8 *efx_rx_buf_va(struct efx_rx_buffer *buf) { - return buf->page_offset + efx->type->rx_buffer_hash_size; -} -static inline unsigned int efx_rx_buf_size(struct efx_nic *efx) -{ - return PAGE_SIZE << efx->rx_buffer_order; -} - -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) + buf->page_offset; } static inline u32 efx_rx_buf_hash(const u8 *eh) @@ -119,66 +74,81 @@ static inline u32 efx_rx_buf_hash(const u8 *eh) #endif } -/** - * 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) +static inline struct efx_rx_buffer * +efx_rx_buf_next(struct efx_rx_queue *rx_queue, struct efx_rx_buffer *rx_buf) +{ + if (unlikely(rx_buf == efx_rx_buffer(rx_queue, rx_queue->ptr_mask))) + return efx_rx_buffer(rx_queue, 0); + else + return rx_buf + 1; +} + +static inline void efx_sync_rx_buffer(struct efx_nic *efx, + struct efx_rx_buffer *rx_buf, + unsigned int len) +{ + dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len, + DMA_FROM_DEVICE); +} + +void efx_rx_config_page_split(struct efx_nic *efx) +{ + efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + EFX_PAGE_IP_ALIGN, + L1_CACHE_BYTES); + efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 : + ((PAGE_SIZE - sizeof(struct efx_rx_page_state)) / + efx->rx_page_buf_step); + efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) / + efx->rx_bufs_per_page; + efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH, + efx->rx_bufs_per_page); +} + +/* Check the RX page recycle ring for a page that can be reused. */ +static struct page *efx_reuse_page(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; + struct page *page; + struct efx_rx_page_state *state; + unsigned index; - 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; - } + index = rx_queue->page_remove & rx_queue->page_ptr_mask; + page = rx_queue->page_ring[index]; + if (page == NULL) + return NULL; + + rx_queue->page_ring[index] = NULL; + /* page_remove cannot exceed page_add. */ + if (rx_queue->page_remove != rx_queue->page_add) + ++rx_queue->page_remove; - ++rx_queue->added_count; - ++rx_queue->alloc_skb_count; + /* If page_count is 1 then we hold the only reference to this page. */ + if (page_count(page) == 1) { + ++rx_queue->page_recycle_count; + return page; + } else { + state = page_address(page); + dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, + PAGE_SIZE << efx->rx_buffer_order, + DMA_FROM_DEVICE); + put_page(page); + ++rx_queue->page_recycle_failed; } - return 0; + return NULL; } /** - * 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 * - * This allocates memory for EFX_RX_BATCH receive buffers, maps them for DMA, - * and populates struct efx_rx_buffers for each one. Return a negative error - * 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. + * This allocates a batch of pages, maps them for DMA, and populates + * struct efx_rx_buffers for each one. Return a negative error code or + * 0 on success. If a single page can be used for multiple buffers, + * then the page will either be inserted fully, or not 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; @@ -188,150 +158,140 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue) dma_addr_t dma_addr; unsigned index, count; - /* We can split a page between two buffers */ - BUILD_BUG_ON(EFX_RX_BATCH & 1); - - for (count = 0; count < EFX_RX_BATCH; ++count) { - page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC, - efx->rx_buffer_order); - if (unlikely(page == NULL)) - return -ENOMEM; - dma_addr = dma_map_page(&efx->pci_dev->dev, page, 0, - efx_rx_buf_size(efx), - DMA_FROM_DEVICE); - if (unlikely(dma_mapping_error(&efx->pci_dev->dev, dma_addr))) { - __free_pages(page, efx->rx_buffer_order); - return -EIO; + count = 0; + do { + page = efx_reuse_page(rx_queue); + if (page == NULL) { + page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC, + efx->rx_buffer_order); + if (unlikely(page == NULL)) + return -ENOMEM; + dma_addr = + dma_map_page(&efx->pci_dev->dev, page, 0, + PAGE_SIZE << efx->rx_buffer_order, + DMA_FROM_DEVICE); + if (unlikely(dma_mapping_error(&efx->pci_dev->dev, + dma_addr))) { + __free_pages(page, efx->rx_buffer_order); + return -EIO; + } + state = page_address(page); + state->dma_addr = dma_addr; + } else { + state = page_address(page); + dma_addr = state->dma_addr; } - state = page_address(page); - state->refcnt = 0; - state->dma_addr = dma_addr; dma_addr += sizeof(struct efx_rx_page_state); page_offset = sizeof(struct efx_rx_page_state); - split: - 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_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_queue->added_count; - ++rx_queue->alloc_page_count; - ++state->refcnt; - - if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) { - /* Use the second half of the page */ + do { + 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->page = page; + rx_buf->page_offset = page_offset + EFX_PAGE_IP_ALIGN; + rx_buf->len = efx->rx_dma_len; + rx_buf->flags = 0; + ++rx_queue->added_count; get_page(page); - dma_addr += (PAGE_SIZE >> 1); - page_offset += (PAGE_SIZE >> 1); - ++count; - goto split; - } - } + dma_addr += efx->rx_page_buf_step; + page_offset += efx->rx_page_buf_step; + } while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE); + + rx_buf->flags = EFX_RX_BUF_LAST_IN_PAGE; + } while (++count < efx->rx_pages_per_batch); return 0; } +/* Unmap a DMA-mapped page. This function is only called for the final RX + * buffer in a page. + */ static void efx_unmap_rx_buffer(struct efx_nic *efx, - struct efx_rx_buffer *rx_buf, - unsigned int used_len) + struct efx_rx_buffer *rx_buf) { - if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) { - struct efx_rx_page_state *state; - - state = page_address(rx_buf->u.page); - if (--state->refcnt == 0) { - dma_unmap_page(&efx->pci_dev->dev, - state->dma_addr, - efx_rx_buf_size(efx), - DMA_FROM_DEVICE); - } else if (used_len) { - dma_sync_single_for_cpu(&efx->pci_dev->dev, - 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); + struct page *page = rx_buf->page; + + if (page) { + struct efx_rx_page_state *state = page_address(page); + dma_unmap_page(&efx->pci_dev->dev, + state->dma_addr, + PAGE_SIZE << efx->rx_buffer_order, + DMA_FROM_DEVICE); } } -static void efx_free_rx_buffer(struct efx_nic *efx, - struct efx_rx_buffer *rx_buf) +static void efx_free_rx_buffer(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) { + put_page(rx_buf->page); + rx_buf->page = NULL; } } -static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue, - struct efx_rx_buffer *rx_buf) +/* Attempt to recycle the page if there is an RX recycle ring; the page can + * only be added if this is the final RX buffer, to prevent pages being used in + * the descriptor ring and appearing in the recycle ring simultaneously. + */ +static void efx_recycle_rx_page(struct efx_channel *channel, + struct efx_rx_buffer *rx_buf) { - efx_unmap_rx_buffer(rx_queue->efx, rx_buf, 0); - efx_free_rx_buffer(rx_queue->efx, rx_buf); -} + struct page *page = rx_buf->page; + struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); + struct efx_nic *efx = rx_queue->efx; + unsigned index; -/* Attempt to resurrect the other receive buffer that used to share this page, - * which had previously been passed up to the kernel and freed. */ -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_buffer *new_buf; - unsigned fill_level, index; - - /* +1 because efx_rx_packet() incremented removed_count. +1 because - * we'd like to insert an additional descriptor whilst leaving - * EFX_RXD_HEAD_ROOM for the non-recycle path */ - fill_level = (rx_queue->added_count - rx_queue->removed_count + 2); - if (unlikely(fill_level > rx_queue->max_fill)) { - /* We could place "state" on a list, and drain the list in - * efx_fast_push_rx_descriptors(). For now, this will do. */ + /* Only recycle the page after processing the final buffer. */ + if (!(rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE)) return; - } - ++state->refcnt; - get_page(rx_buf->u.page); + index = rx_queue->page_add & rx_queue->page_ptr_mask; + if (rx_queue->page_ring[index] == NULL) { + unsigned read_index = rx_queue->page_remove & + rx_queue->page_ptr_mask; - 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->len = rx_buf->len; - new_buf->flags = EFX_RX_BUF_PAGE; - ++rx_queue->added_count; + /* The next slot in the recycle ring is available, but + * increment page_remove if the read pointer currently + * points here. + */ + if (read_index == index) + ++rx_queue->page_remove; + rx_queue->page_ring[index] = page; + ++rx_queue->page_add; + return; + } + ++rx_queue->page_recycle_full; + efx_unmap_rx_buffer(efx, rx_buf); + put_page(rx_buf->page); } -/* Recycle the given rx buffer directly back into the rx_queue. There is - * always room to add this buffer, because we've just popped a buffer. */ -static void efx_recycle_rx_buffer(struct efx_channel *channel, - struct efx_rx_buffer *rx_buf) +static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue, + struct efx_rx_buffer *rx_buf) { - struct efx_nic *efx = channel->efx; - struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); - struct efx_rx_buffer *new_buf; - unsigned index; - - rx_buf->flags &= EFX_RX_BUF_PAGE; - - if ((rx_buf->flags & EFX_RX_BUF_PAGE) && - efx->rx_buffer_len <= EFX_RX_HALF_PAGE && - page_count(rx_buf->u.page) == 1) - efx_resurrect_rx_buffer(rx_queue, rx_buf); + /* Release the page reference we hold for the buffer. */ + if (rx_buf->page) + put_page(rx_buf->page); + + /* If this is the last buffer in a page, unmap and free it. */ + if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) { + efx_unmap_rx_buffer(rx_queue->efx, rx_buf); + efx_free_rx_buffer(rx_buf); + } + rx_buf->page = NULL; +} - index = rx_queue->added_count & rx_queue->ptr_mask; - new_buf = efx_rx_buffer(rx_queue, index); +/* Recycle the pages that are used by buffers that have just been received. */ +static void efx_recycle_rx_buffers(struct efx_channel *channel, + struct efx_rx_buffer *rx_buf, + unsigned int n_frags) +{ + struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); - memcpy(new_buf, rx_buf, sizeof(*new_buf)); - rx_buf->u.page = NULL; - ++rx_queue->added_count; + do { + efx_recycle_rx_page(channel, rx_buf); + rx_buf = efx_rx_buf_next(rx_queue, rx_buf); + } while (--n_frags); } /** @@ -348,8 +308,8 @@ static void efx_recycle_rx_buffer(struct efx_channel *channel, */ 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; + struct efx_nic *efx = rx_queue->efx; + unsigned int fill_level, batch_size; int space, rc = 0; /* Calculate current fill level, and exit if we don't need to fill */ @@ -364,28 +324,26 @@ void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue) rx_queue->min_fill = fill_level; } + batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page; space = rx_queue->max_fill - fill_level; - EFX_BUG_ON_PARANOID(space < EFX_RX_BATCH); + EFX_BUG_ON_PARANOID(space < batch_size); 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) efx_schedule_slow_fill(rx_queue); goto out; } - } while ((space -= EFX_RX_BATCH) >= EFX_RX_BATCH); + } while ((space -= batch_size) >= batch_size); netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev, "RX queue %d fast-filled descriptor ring " @@ -408,7 +366,7 @@ void efx_rx_slow_fill(unsigned long context) 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; @@ -428,11 +386,6 @@ static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue, "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()) @@ -448,212 +401,238 @@ static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue, /* Pass a received packet up through GRO. GRO can handle pages * regardless of checksum state and skbs with a good checksum. */ -static void efx_rx_packet_gro(struct efx_channel *channel, - struct efx_rx_buffer *rx_buf, - const u8 *eh) +static void +efx_rx_packet_gro(struct efx_channel *channel, struct efx_rx_buffer *rx_buf, + unsigned int n_frags, u8 *eh) { struct napi_struct *napi = &channel->napi_str; gro_result_t gro_result; + struct efx_nic *efx = channel->efx; + 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; + skb = napi_get_frags(napi); + if (unlikely(!skb)) { + while (n_frags--) { + put_page(rx_buf->page); + rx_buf->page = NULL; + rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); + } + return; + } - rx_buf->u.page = NULL; + if (efx->net_dev->features & NETIF_F_RXHASH) + skb->rxhash = efx_rx_buf_hash(eh); + skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ? + CHECKSUM_UNNECESSARY : CHECKSUM_NONE); + + for (;;) { + skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, + rx_buf->page, rx_buf->page_offset, + rx_buf->len); + rx_buf->page = NULL; + skb->len += rx_buf->len; + if (skb_shinfo(skb)->nr_frags == n_frags) + break; + + rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); + } - skb = napi_get_frags(napi); - if (!skb) { - put_page(page); - return; - } + skb->data_len = skb->len; + skb->truesize += n_frags * efx->rx_buffer_truesize; + + skb_record_rx_queue(skb, channel->rx_queue.core_index); + + gro_result = napi_gro_frags(napi); + if (gro_result != GRO_DROP) + channel->irq_mod_score += 2; +} - if (efx->net_dev->features & NETIF_F_RXHASH) - skb->rxhash = efx_rx_buf_hash(eh); +/* Allocate and construct an SKB around page fragments */ +static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel, + struct efx_rx_buffer *rx_buf, + unsigned int n_frags, + u8 *eh, int hdr_len) +{ + struct efx_nic *efx = channel->efx; + struct sk_buff *skb; - skb_fill_page_desc(skb, 0, page, - efx_rx_buf_offset(efx, rx_buf), rx_buf->len); + /* 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; - 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); + EFX_BUG_ON_PARANOID(rx_buf->len < hdr_len); - skb_record_rx_queue(skb, channel->rx_queue.core_index); + skb_reserve(skb, EFX_PAGE_SKB_ALIGN); + memcpy(__skb_put(skb, hdr_len), eh, hdr_len); - gro_result = napi_gro_frags(napi); - } else { - struct sk_buff *skb = rx_buf->u.skb; + /* Append the remaining page(s) onto the frag list */ + if (rx_buf->len > hdr_len) { + rx_buf->page_offset += hdr_len; + rx_buf->len -= hdr_len; - EFX_BUG_ON_PARANOID(!(rx_buf->flags & EFX_RX_PKT_CSUMMED)); - rx_buf->u.skb = NULL; - skb->ip_summed = CHECKSUM_UNNECESSARY; + for (;;) { + skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, + rx_buf->page, rx_buf->page_offset, + rx_buf->len); + rx_buf->page = NULL; + skb->len += rx_buf->len; + skb->data_len += rx_buf->len; + if (skb_shinfo(skb)->nr_frags == n_frags) + break; - gro_result = napi_gro_receive(napi, skb); + rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf); + } + } else { + __free_pages(rx_buf->page, efx->rx_buffer_order); + rx_buf->page = NULL; + n_frags = 0; } - 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; - } + skb->truesize += n_frags * efx->rx_buffer_truesize; + + /* 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, - unsigned int len, u16 flags) + unsigned int n_frags, unsigned int len, u16 flags) { 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; - /* This allows the refill path to post another buffer. - * EFX_RXD_HEAD_ROOM ensures that the slot we are using - * isn't overwritten yet. - */ - 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); + /* Validate the number of fragments and completed length */ + if (n_frags == 1) { + efx_rx_packet__check_len(rx_queue, rx_buf, len); + } else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) || + unlikely(len <= (n_frags - 1) * EFX_RX_USR_BUF_SIZE) || + unlikely(len > n_frags * EFX_RX_USR_BUF_SIZE) || + unlikely(!efx->rx_scatter)) { + /* If this isn't an explicit discard request, either + * the hardware or the driver is broken. + */ + WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD)); + rx_buf->flags |= EFX_RX_PKT_DISCARD; + } netif_vdbg(efx, rx_status, efx->net_dev, - "RX queue %d received id %x at %llx+%x %s%s\n", + "RX queue %d received ids %x-%x len %d %s%s\n", efx_rx_queue_index(rx_queue), index, - (unsigned long long)rx_buf->dma_addr, len, + (index + n_frags - 1) & rx_queue->ptr_mask, len, (rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "", (rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : ""); - /* Discard packet, if instructed to do so */ + /* Discard packet, if instructed to do so. Process the + * previous receive first. + */ 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); - - /* Don't hold off the previous receive */ - rx_buf = NULL; - goto out; + efx_rx_flush_packet(channel); + put_page(rx_buf->page); + efx_recycle_rx_buffers(channel, rx_buf, n_frags); + return; } - /* Release and/or sync DMA mapping - assumes all RX buffers - * consumed in-order per RX queue + if (n_frags == 1) + rx_buf->len = len; + + /* Release and/or sync the DMA mapping - assumes all RX buffers + * consumed in-order per RX queue. */ - efx_unmap_rx_buffer(efx, rx_buf, len); + efx_sync_rx_buffer(efx, rx_buf, rx_buf->len); /* Prefetch nice and early so data will (hopefully) be in cache by * the time we look at it. */ - prefetch(efx_rx_buf_eh(efx, rx_buf)); + prefetch(efx_rx_buf_va(rx_buf)); + + rx_buf->page_offset += efx->type->rx_buffer_hash_size; + rx_buf->len -= efx->type->rx_buffer_hash_size; + + if (n_frags > 1) { + /* Release/sync DMA mapping for additional fragments. + * Fix length for last fragment. + */ + unsigned int tail_frags = n_frags - 1; + + for (;;) { + rx_buf = efx_rx_buf_next(rx_queue, rx_buf); + if (--tail_frags == 0) + break; + efx_sync_rx_buffer(efx, rx_buf, EFX_RX_USR_BUF_SIZE); + } + rx_buf->len = len - (n_frags - 1) * EFX_RX_USR_BUF_SIZE; + efx_sync_rx_buffer(efx, rx_buf, rx_buf->len); + } + + /* All fragments have been DMA-synced, so recycle buffers and pages. */ + rx_buf = efx_rx_buffer(rx_queue, index); + efx_recycle_rx_buffers(channel, rx_buf, n_frags); /* Pipeline receives so that we give time for packet headers to be * prefetched into cache. */ - rx_buf->len = len - efx->type->rx_buffer_hash_size; -out: - if (channel->rx_pkt) - __efx_rx_packet(channel, channel->rx_pkt); - channel->rx_pkt = rx_buf; + efx_rx_flush_packet(channel); + channel->rx_pkt_n_frags = n_frags; + channel->rx_pkt_index = index; } -static void efx_rx_deliver(struct efx_channel *channel, - struct efx_rx_buffer *rx_buf) +static void efx_rx_deliver(struct efx_channel *channel, u8 *eh, + struct efx_rx_buffer *rx_buf, + unsigned int n_frags) { 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, n_frags, eh, hdr_len); + if (unlikely(skb == NULL)) { + efx_free_rx_buffer(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); - - /* Pass the packet up */ if (channel->type->receive_skb) - channel->type->receive_skb(channel, skb); - else - netif_receive_skb(skb); + if (channel->type->receive_skb(channel, skb)) + return; - /* Update allocation strategy method */ - channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB; + /* Pass the packet up */ + netif_receive_skb(skb); } /* Handle a received packet. Second half: Touches packet payload. */ -void __efx_rx_packet(struct efx_channel *channel, struct efx_rx_buffer *rx_buf) +void __efx_rx_packet(struct efx_channel *channel) { struct efx_nic *efx = channel->efx; - u8 *eh = efx_rx_buf_eh(efx, rx_buf); + struct efx_rx_buffer *rx_buf = + efx_rx_buffer(&channel->rx_queue, channel->rx_pkt_index); + u8 *eh = efx_rx_buf_va(rx_buf); /* If we're in loopback test, then pass the packet directly to the * loopback layer, and free the rx_buf here */ if (unlikely(efx->loopback_selftest)) { efx_loopback_rx_packet(efx, eh, rx_buf->len); - efx_free_rx_buffer(efx, rx_buf); - 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); + efx_free_rx_buffer(rx_buf); + goto out; } 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) - efx_rx_packet_gro(channel, rx_buf, eh); + if (!channel->type->receive_skb) + efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, 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, channel->rx_pkt_n_frags); +out: + channel->rx_pkt_n_frags = 0; } int efx_probe_rx_queue(struct efx_rx_queue *rx_queue) @@ -683,9 +662,32 @@ int efx_probe_rx_queue(struct efx_rx_queue *rx_queue) kfree(rx_queue->buffer); rx_queue->buffer = NULL; } + return rc; } +static void efx_init_rx_recycle_ring(struct efx_nic *efx, + struct efx_rx_queue *rx_queue) +{ + unsigned int bufs_in_recycle_ring, page_ring_size; + + /* Set the RX recycle ring size */ +#ifdef CONFIG_PPC64 + bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU; +#else + if (efx->pci_dev->dev.iommu_group) + bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_IOMMU; + else + bufs_in_recycle_ring = EFX_RECYCLE_RING_SIZE_NOIOMMU; +#endif /* CONFIG_PPC64 */ + + page_ring_size = roundup_pow_of_two(bufs_in_recycle_ring / + efx->rx_bufs_per_page); + rx_queue->page_ring = kcalloc(page_ring_size, + sizeof(*rx_queue->page_ring), GFP_KERNEL); + rx_queue->page_ptr_mask = page_ring_size - 1; +} + void efx_init_rx_queue(struct efx_rx_queue *rx_queue) { struct efx_nic *efx = rx_queue->efx; @@ -699,10 +701,18 @@ void efx_init_rx_queue(struct efx_rx_queue *rx_queue) rx_queue->notified_count = 0; rx_queue->removed_count = 0; rx_queue->min_fill = -1U; + efx_init_rx_recycle_ring(efx, rx_queue); + + rx_queue->page_remove = 0; + rx_queue->page_add = rx_queue->page_ptr_mask + 1; + rx_queue->page_recycle_count = 0; + rx_queue->page_recycle_failed = 0; + rx_queue->page_recycle_full = 0; /* Initialise limit fields */ max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM; - max_trigger = max_fill - EFX_RX_BATCH; + max_trigger = + max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page; if (rx_refill_threshold != 0) { trigger = max_fill * min(rx_refill_threshold, 100U) / 100U; if (trigger > max_trigger) @@ -722,6 +732,7 @@ void efx_init_rx_queue(struct efx_rx_queue *rx_queue) void efx_fini_rx_queue(struct efx_rx_queue *rx_queue) { int i; + struct efx_nic *efx = rx_queue->efx; struct efx_rx_buffer *rx_buf; netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev, @@ -733,13 +744,32 @@ void efx_fini_rx_queue(struct efx_rx_queue *rx_queue) del_timer_sync(&rx_queue->slow_fill); efx_nic_fini_rx(rx_queue); - /* Release RX buffers NB start at index 0 not current HW ptr */ + /* Release RX buffers from the current read ptr to the write ptr */ if (rx_queue->buffer) { - for (i = 0; i <= rx_queue->ptr_mask; i++) { - rx_buf = efx_rx_buffer(rx_queue, i); + for (i = rx_queue->removed_count; i < rx_queue->added_count; + i++) { + unsigned index = i & rx_queue->ptr_mask; + rx_buf = efx_rx_buffer(rx_queue, index); efx_fini_rx_buffer(rx_queue, rx_buf); } } + + /* Unmap and release the pages in the recycle ring. Remove the ring. */ + for (i = 0; i <= rx_queue->page_ptr_mask; i++) { + struct page *page = rx_queue->page_ring[i]; + struct efx_rx_page_state *state; + + if (page == NULL) + continue; + + state = page_address(page); + dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, + PAGE_SIZE << efx->rx_buffer_order, + DMA_FROM_DEVICE); + put_page(page); + } + kfree(rx_queue->page_ring); + rx_queue->page_ring = NULL; } void efx_remove_rx_queue(struct efx_rx_queue *rx_queue) @@ -754,9 +784,6 @@ void efx_remove_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 (%)"); |
