From 668dda06d48fc16a5b40e6a32057bd18589e3f95 Mon Sep 17 00:00:00 2001 From: Sunil Goutham Date: Mon, 7 Dec 2015 10:30:33 +0530 Subject: [PATCH] net, thunderx: Remove unnecessary rcv buffer start address management Since we have moved on to using allocated pages to carve receive buffers instead of netdev_alloc_skb() there is no need to store any pointers for later retrieval. Earlier we had to store skb and skb->data pointers which later are used to handover received packet to network stack. This will avoid an unnecessary cache miss as well. Signed-off-by: Sunil Goutham Signed-off-by: David S. Miller --- .../ethernet/cavium/thunder/nicvf_queues.c | 49 ++++--------------- .../ethernet/cavium/thunder/nicvf_queues.h | 10 +--- 2 files changed, 11 insertions(+), 48 deletions(-) diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c index 99a29d0b5918..1fbd9084333e 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c @@ -18,14 +18,6 @@ #include "q_struct.h" #include "nicvf_queues.h" -struct rbuf_info { - struct page *page; - void *data; - u64 offset; -}; - -#define GET_RBUF_INFO(x) ((struct rbuf_info *)(x - NICVF_RCV_BUF_ALIGN_BYTES)) - /* Poll a register for a specific value */ static int nicvf_poll_reg(struct nicvf *nic, int qidx, u64 reg, int bit_pos, int bits, int val) @@ -86,8 +78,6 @@ static void nicvf_free_q_desc_mem(struct nicvf *nic, struct q_desc_mem *dmem) static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, gfp_t gfp, u32 buf_len, u64 **rbuf) { - u64 data; - struct rbuf_info *rinfo; int order = get_order(buf_len); /* Check if request can be accomodated in previous allocated page */ @@ -113,46 +103,28 @@ static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, gfp_t gfp, nic->rb_page_offset = 0; } - data = (u64)page_address(nic->rb_page) + nic->rb_page_offset; - - /* Align buffer addr to cache line i.e 128 bytes */ - rinfo = (struct rbuf_info *)(data + NICVF_RCV_BUF_ALIGN_LEN(data)); - /* Save page address for reference updation */ - rinfo->page = nic->rb_page; - /* Store start address for later retrieval */ - rinfo->data = (void *)data; - /* Store alignment offset */ - rinfo->offset = NICVF_RCV_BUF_ALIGN_LEN(data); + *rbuf = (u64 *)((u64)page_address(nic->rb_page) + nic->rb_page_offset); - data += rinfo->offset; - - /* Give next aligned address to hw for DMA */ - *rbuf = (u64 *)(data + NICVF_RCV_BUF_ALIGN_BYTES); return 0; } -/* Retrieve actual buffer start address and build skb for received packet */ +/* Build skb around receive buffer */ static struct sk_buff *nicvf_rb_ptr_to_skb(struct nicvf *nic, u64 rb_ptr, int len) { + void *data; struct sk_buff *skb; - struct rbuf_info *rinfo; - rb_ptr = (u64)phys_to_virt(rb_ptr); - /* Get buffer start address and alignment offset */ - rinfo = GET_RBUF_INFO(rb_ptr); + data = phys_to_virt(rb_ptr); /* Now build an skb to give to stack */ - skb = build_skb(rinfo->data, RCV_FRAG_LEN); + skb = build_skb(data, RCV_FRAG_LEN); if (!skb) { - put_page(rinfo->page); + put_page(virt_to_page(data)); return NULL; } - /* Set correct skb->data */ - skb_reserve(skb, rinfo->offset + NICVF_RCV_BUF_ALIGN_BYTES); - - prefetch((void *)rb_ptr); + prefetch(skb->data); return skb; } @@ -196,7 +168,6 @@ static void nicvf_free_rbdr(struct nicvf *nic, struct rbdr *rbdr) int head, tail; u64 buf_addr; struct rbdr_entry_t *desc; - struct rbuf_info *rinfo; if (!rbdr) return; @@ -212,16 +183,14 @@ static void nicvf_free_rbdr(struct nicvf *nic, struct rbdr *rbdr) while (head != tail) { desc = GET_RBDR_DESC(rbdr, head); buf_addr = desc->buf_addr << NICVF_RCV_BUF_ALIGN; - rinfo = GET_RBUF_INFO((u64)phys_to_virt(buf_addr)); - put_page(rinfo->page); + put_page(virt_to_page(phys_to_virt(buf_addr))); head++; head &= (rbdr->dmem.q_len - 1); } /* Free SKB of tail desc */ desc = GET_RBDR_DESC(rbdr, tail); buf_addr = desc->buf_addr << NICVF_RCV_BUF_ALIGN; - rinfo = GET_RBUF_INFO((u64)phys_to_virt(buf_addr)); - put_page(rinfo->page); + put_page(virt_to_page(phys_to_virt(buf_addr))); /* Free RBDR ring */ nicvf_free_q_desc_mem(nic, &rbdr->dmem); diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h index 033e8306e91c..a4f6667fdbd4 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.h +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.h @@ -83,10 +83,8 @@ #define MAX_RCV_BUF_COUNT (1ULL << (RBDR_SIZE6 + 13)) #define RBDR_THRESH (RCV_BUF_COUNT / 2) #define DMA_BUFFER_LEN 2048 /* In multiples of 128bytes */ -#define RCV_FRAG_LEN (SKB_DATA_ALIGN(DMA_BUFFER_LEN + NET_SKB_PAD) + \ - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) + \ - (NICVF_RCV_BUF_ALIGN_BYTES * 2)) -#define RCV_DATA_OFFSET NICVF_RCV_BUF_ALIGN_BYTES +#define RCV_FRAG_LEN (SKB_DATA_ALIGN(DMA_BUFFER_LEN + NET_SKB_PAD) + \ + SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) #define MAX_CQES_FOR_TX ((SND_QUEUE_LEN / MIN_SQ_DESC_PER_PKT_XMIT) * \ MAX_CQE_PER_PKT_XMIT) @@ -108,10 +106,6 @@ #define NICVF_SQ_BASE_ALIGN_BYTES 128 /* 7 bits */ #define NICVF_ALIGNED_ADDR(ADDR, ALIGN_BYTES) ALIGN(ADDR, ALIGN_BYTES) -#define NICVF_ADDR_ALIGN_LEN(ADDR, BYTES)\ - (NICVF_ALIGNED_ADDR(ADDR, BYTES) - BYTES) -#define NICVF_RCV_BUF_ALIGN_LEN(X)\ - (NICVF_ALIGNED_ADDR(X, NICVF_RCV_BUF_ALIGN_BYTES) - X) /* Queue enable/disable */ #define NICVF_SQ_EN BIT_ULL(19) -- 2.30.2