cregit-Linux how code gets into the kernel

Release 4.11 drivers/net/ethernet/intel/i40evf/i40e_txrx.h

/*******************************************************************************
 *
 * Intel Ethernet Controller XL710 Family Linux Virtual Function Driver
 * Copyright(c) 2013 - 2016 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Contact Information:
 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 ******************************************************************************/

#ifndef _I40E_TXRX_H_

#define _I40E_TXRX_H_

/* Interrupt Throttling and Rate Limiting Goodies */


#define I40E_MAX_ITR               0x0FF0  
/* reg uses 2 usec resolution */

#define I40E_MIN_ITR               0x0001  
/* reg uses 2 usec resolution */

#define I40E_ITR_100K              0x0005

#define I40E_ITR_50K               0x000A

#define I40E_ITR_20K               0x0019

#define I40E_ITR_18K               0x001B

#define I40E_ITR_8K                0x003E

#define I40E_ITR_4K                0x007A

#define I40E_MAX_INTRL             0x3B    
/* reg uses 4 usec resolution */

#define I40E_ITR_RX_DEF            I40E_ITR_20K

#define I40E_ITR_TX_DEF            I40E_ITR_20K

#define I40E_ITR_DYNAMIC           0x8000  
/* use top bit as a flag */

#define I40E_MIN_INT_RATE          250     
/* ~= 1000000 / (I40E_MAX_ITR * 2) */

#define I40E_MAX_INT_RATE          500000  
/* == 1000000 / (I40E_MIN_ITR * 2) */

#define I40E_DEFAULT_IRQ_WORK      256

#define ITR_TO_REG(setting) ((setting & ~I40E_ITR_DYNAMIC) >> 1)

#define ITR_IS_DYNAMIC(setting) (!!(setting & I40E_ITR_DYNAMIC))

#define ITR_REG_TO_USEC(itr_reg) (itr_reg << 1)
/* 0x40 is the enable bit for interrupt rate limiting, and must be set if
 * the value of the rate limit is non-zero
 */

#define INTRL_ENA                  BIT(6)

#define INTRL_REG_TO_USEC(intrl) ((intrl & ~INTRL_ENA) << 2)

#define INTRL_USEC_TO_REG(set) ((set) ? ((set) >> 2) | INTRL_ENA : 0)

#define I40E_INTRL_8K              125     
/* 8000 ints/sec */

#define I40E_INTRL_62K             16      
/* 62500 ints/sec */

#define I40E_INTRL_83K             12      
/* 83333 ints/sec */


#define I40E_QUEUE_END_OF_LIST 0x7FF

/* this enum matches hardware bits and is meant to be used by DYN_CTLN
 * registers and QINT registers or more generally anywhere in the manual
 * mentioning ITR_INDX, ITR_NONE cannot be used as an index 'n' into any
 * register but instead is a special value meaning "don't update" ITR0/1/2.
 */

enum i40e_dyn_idx_t {
	
I40E_IDX_ITR0 = 0,
	
I40E_IDX_ITR1 = 1,
	
I40E_IDX_ITR2 = 2,
	
I40E_ITR_NONE = 3	/* ITR_NONE must not be used as an index */
};

/* these are indexes into ITRN registers */

#define I40E_RX_ITR    I40E_IDX_ITR0

#define I40E_TX_ITR    I40E_IDX_ITR1

#define I40E_PE_ITR    I40E_IDX_ITR2

/* Supported RSS offloads */

#define I40E_DEFAULT_RSS_HENA ( \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_UDP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_SCTP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_TCP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_OTHER) | \
        BIT_ULL(I40E_FILTER_PCTYPE_FRAG_IPV4) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_UDP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_TCP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_SCTP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_OTHER) | \
        BIT_ULL(I40E_FILTER_PCTYPE_FRAG_IPV6) | \
        BIT_ULL(I40E_FILTER_PCTYPE_L2_PAYLOAD))


#define I40E_DEFAULT_RSS_HENA_EXPANDED (I40E_DEFAULT_RSS_HENA | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV4_TCP_SYN_NO_ACK) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_UNICAST_IPV4_UDP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_MULTICAST_IPV4_UDP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_IPV6_TCP_SYN_NO_ACK) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_UNICAST_IPV6_UDP) | \
        BIT_ULL(I40E_FILTER_PCTYPE_NONF_MULTICAST_IPV6_UDP))


#define i40e_pf_get_default_rss_hena(pf) \
	(((pf)->flags & I40E_FLAG_MULTIPLE_TCP_UDP_RSS_PCTYPE) ? \
          I40E_DEFAULT_RSS_HENA_EXPANDED : I40E_DEFAULT_RSS_HENA)

/* Supported Rx Buffer Sizes (a multiple of 128) */

#define I40E_RXBUFFER_256   256

#define I40E_RXBUFFER_2048  2048

#define I40E_RXBUFFER_3072  3072   
/* For FCoE MTU of 2158 */

#define I40E_RXBUFFER_4096  4096

#define I40E_RXBUFFER_8192  8192

#define I40E_MAX_RXBUFFER   9728  
/* largest size for single descriptor */

/* NOTE: netdev_alloc_skb reserves up to 64 bytes, NET_IP_ALIGN means we
 * reserve 2 more, and skb_shared_info adds an additional 384 bytes more,
 * this adds up to 512 bytes of extra data meaning the smallest allocation
 * we could have is 1K.
 * i.e. RXBUFFER_256 --> 960 byte skb (size-1024 slab)
 * i.e. RXBUFFER_512 --> 1216 byte skb (size-2048 slab)
 */

#define I40E_RX_HDR_SIZE I40E_RXBUFFER_256

#define i40e_rx_desc i40e_32byte_rx_desc

/**
 * i40e_test_staterr - tests bits in Rx descriptor status and error fields
 * @rx_desc: pointer to receive descriptor (in le64 format)
 * @stat_err_bits: value to mask
 *
 * This function does some fast chicanery in order to return the
 * value of the mask which is really only used for boolean tests.
 * The status_error_len doesn't need to be shifted because it begins
 * at offset zero.
 */

static inline bool i40e_test_staterr(union i40e_rx_desc *rx_desc, const u64 stat_err_bits) { return !!(rx_desc->wb.qword1.status_error_len & cpu_to_le64(stat_err_bits)); }

Contributors

PersonTokensPropCommitsCommitProp
Jesse Brandeburg34100.00%1100.00%
Total34100.00%1100.00%

/* How many Rx Buffers do we bundle into one write to the hardware ? */ #define I40E_RX_BUFFER_WRITE 16 /* Must be power of 2 */ #define I40E_RX_INCREMENT(r, i) \ do { \ (i)++; \ if ((i) == (r)->count) \ i = 0; \ r->next_to_clean = i; \ } while (0) #define I40E_RX_NEXT_DESC(r, i, n) \ do { \ (i)++; \ if ((i) == (r)->count) \ i = 0; \ (n) = I40E_RX_DESC((r), (i)); \ } while (0) #define I40E_RX_NEXT_DESC_PREFETCH(r, i, n) \ do { \ I40E_RX_NEXT_DESC((r), (i), (n)); \ prefetch((n)); \ } while (0) #define I40E_MAX_BUFFER_TXD 8 #define I40E_MIN_TX_LEN 17 /* The size limit for a transmit buffer in a descriptor is (16K - 1). * In order to align with the read requests we will align the value to * the nearest 4K which represents our maximum read request size. */ #define I40E_MAX_READ_REQ_SIZE 4096 #define I40E_MAX_DATA_PER_TXD (16 * 1024 - 1) #define I40E_MAX_DATA_PER_TXD_ALIGNED \ (I40E_MAX_DATA_PER_TXD & ~(I40E_MAX_READ_REQ_SIZE - 1)) /** * i40e_txd_use_count - estimate the number of descriptors needed for Tx * @size: transmit request size in bytes * * Due to hardware alignment restrictions (4K alignment), we need to * assume that we can have no more than 12K of data per descriptor, even * though each descriptor can take up to 16K - 1 bytes of aligned memory. * Thus, we need to divide by 12K. But division is slow! Instead, * we decompose the operation into shifts and one relatively cheap * multiply operation. * * To divide by 12K, we first divide by 4K, then divide by 3: * To divide by 4K, shift right by 12 bits * To divide by 3, multiply by 85, then divide by 256 * (Divide by 256 is done by shifting right by 8 bits) * Finally, we add one to round up. Because 256 isn't an exact multiple of * 3, we'll underestimate near each multiple of 12K. This is actually more * accurate as we have 4K - 1 of wiggle room that we can fit into the last * segment. For our purposes this is accurate out to 1M which is orders of * magnitude greater than our largest possible GSO size. * * This would then be implemented as: * return (((size >> 12) * 85) >> 8) + 1; * * Since multiplication and division are commutative, we can reorder * operations into: * return ((size * 85) >> 20) + 1; */
static inline unsigned int i40e_txd_use_count(unsigned int size) { return ((size * 85) >> 20) + 1; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Duyck1872.00%133.33%
Mitch A Williams520.00%133.33%
Greg Rose28.00%133.33%
Total25100.00%3100.00%

/* Tx Descriptors needed, worst case */ #define DESC_NEEDED (MAX_SKB_FRAGS + 4) #define I40E_MIN_DESC_PENDING 4 #define I40E_TX_FLAGS_HW_VLAN BIT(1) #define I40E_TX_FLAGS_SW_VLAN BIT(2) #define I40E_TX_FLAGS_TSO BIT(3) #define I40E_TX_FLAGS_IPV4 BIT(4) #define I40E_TX_FLAGS_IPV6 BIT(5) #define I40E_TX_FLAGS_FCCRC BIT(6) #define I40E_TX_FLAGS_FSO BIT(7) #define I40E_TX_FLAGS_FD_SB BIT(9) #define I40E_TX_FLAGS_VXLAN_TUNNEL BIT(10) #define I40E_TX_FLAGS_VLAN_MASK 0xffff0000 #define I40E_TX_FLAGS_VLAN_PRIO_MASK 0xe0000000 #define I40E_TX_FLAGS_VLAN_PRIO_SHIFT 29 #define I40E_TX_FLAGS_VLAN_SHIFT 16 struct i40e_tx_buffer { struct i40e_tx_desc *next_to_watch; union { struct sk_buff *skb; void *raw_buf; }; unsigned int bytecount; unsigned short gso_segs; DEFINE_DMA_UNMAP_ADDR(dma); DEFINE_DMA_UNMAP_LEN(len); u32 tx_flags; }; struct i40e_rx_buffer { dma_addr_t dma; struct page *page; unsigned int page_offset; }; struct i40e_queue_stats { u64 packets; u64 bytes; }; struct i40e_tx_queue_stats { u64 restart_queue; u64 tx_busy; u64 tx_done_old; u64 tx_linearize; u64 tx_force_wb; u64 tx_lost_interrupt; }; struct i40e_rx_queue_stats { u64 non_eop_descs; u64 alloc_page_failed; u64 alloc_buff_failed; u64 page_reuse_count; u64 realloc_count; }; enum i40e_ring_state_t { __I40E_TX_FDIR_INIT_DONE, __I40E_TX_XPS_INIT_DONE, }; /* some useful defines for virtchannel interface, which * is the only remaining user of header split */ #define I40E_RX_DTYPE_NO_SPLIT 0 #define I40E_RX_DTYPE_HEADER_SPLIT 1 #define I40E_RX_DTYPE_SPLIT_ALWAYS 2 #define I40E_RX_SPLIT_L2 0x1 #define I40E_RX_SPLIT_IP 0x2 #define I40E_RX_SPLIT_TCP_UDP 0x4 #define I40E_RX_SPLIT_SCTP 0x8 /* struct that defines a descriptor ring, associated with a VSI */ struct i40e_ring { struct i40e_ring *next; /* pointer to next ring in q_vector */ void *desc; /* Descriptor ring memory */ struct device *dev; /* Used for DMA mapping */ struct net_device *netdev; /* netdev ring maps to */ union { struct i40e_tx_buffer *tx_bi; struct i40e_rx_buffer *rx_bi; }; unsigned long state; u16 queue_index; /* Queue number of ring */ u8 dcb_tc; /* Traffic class of ring */ u8 __iomem *tail; /* high bit set means dynamic, use accessors routines to read/write. * hardware only supports 2us resolution for the ITR registers. * these values always store the USER setting, and must be converted * before programming to a register. */ u16 rx_itr_setting; u16 tx_itr_setting; u16 count; /* Number of descriptors */ u16 reg_idx; /* HW register index of the ring */ u16 rx_buf_len; /* used in interrupt processing */ u16 next_to_use; u16 next_to_clean; u8 atr_sample_rate; u8 atr_count; bool ring_active; /* is ring online or not */ bool arm_wb; /* do something to arm write back */ u8 packet_stride; u16 flags; #define I40E_TXR_FLAGS_WB_ON_ITR BIT(0) /* stats structs */ struct i40e_queue_stats stats; struct u64_stats_sync syncp; union { struct i40e_tx_queue_stats tx_stats; struct i40e_rx_queue_stats rx_stats; }; unsigned int size; /* length of descriptor ring in bytes */ dma_addr_t dma; /* physical address of ring */ struct i40e_vsi *vsi; /* Backreference to associated VSI */ struct i40e_q_vector *q_vector; /* Backreference to associated vector */ struct rcu_head rcu; /* to avoid race on free */ u16 next_to_alloc; struct sk_buff *skb; /* When i40evf_clean_rx_ring_irq() must * return before it sees the EOP for * the current packet, we save that skb * here and resume receiving this * packet the next time * i40evf_clean_rx_ring_irq() is called * for this ring. */ } ____cacheline_internodealigned_in_smp; enum i40e_latency_range { I40E_LOWEST_LATENCY = 0, I40E_LOW_LATENCY = 1, I40E_BULK_LATENCY = 2, I40E_ULTRA_LATENCY = 3, }; struct i40e_ring_container { /* array of pointers to rings */ struct i40e_ring *ring; unsigned int total_bytes; /* total bytes processed this int */ unsigned int total_packets; /* total packets processed this int */ u16 count; enum i40e_latency_range latency_range; u16 itr; }; /* iterator for handling rings in ring container */ #define i40e_for_each_ring(pos, head) \ for (pos = (head).ring; pos != NULL; pos = pos->next) bool i40evf_alloc_rx_buffers(struct i40e_ring *rxr, u16 cleaned_count); netdev_tx_t i40evf_xmit_frame(struct sk_buff *skb, struct net_device *netdev); void i40evf_clean_tx_ring(struct i40e_ring *tx_ring); void i40evf_clean_rx_ring(struct i40e_ring *rx_ring); int i40evf_setup_tx_descriptors(struct i40e_ring *tx_ring); int i40evf_setup_rx_descriptors(struct i40e_ring *rx_ring); void i40evf_free_tx_resources(struct i40e_ring *tx_ring); void i40evf_free_rx_resources(struct i40e_ring *rx_ring); int i40evf_napi_poll(struct napi_struct *napi, int budget); void i40evf_force_wb(struct i40e_vsi *vsi, struct i40e_q_vector *q_vector); u32 i40evf_get_tx_pending(struct i40e_ring *ring, bool in_sw); int __i40evf_maybe_stop_tx(struct i40e_ring *tx_ring, int size); bool __i40evf_chk_linearize(struct sk_buff *skb); /** * i40e_get_head - Retrieve head from head writeback * @tx_ring: Tx ring to fetch head of * * Returns value of Tx ring head based on value stored * in head write-back location **/
static inline u32 i40e_get_head(struct i40e_ring *tx_ring) { void *head = (struct i40e_tx_desc *)tx_ring->desc + tx_ring->count; return le32_to_cpu(*(volatile __le32 *)head); }

Contributors

PersonTokensPropCommitsCommitProp
Kiran Patil41100.00%1100.00%
Total41100.00%1100.00%

/** * i40e_xmit_descriptor_count - calculate number of Tx descriptors needed * @skb: send buffer * @tx_ring: ring to send buffer on * * Returns number of data descriptors needed for this skb. Returns 0 to indicate * there is not enough descriptors available in this ring since we need at least * one descriptor. **/
static inline int i40e_xmit_descriptor_count(struct sk_buff *skb) { const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0]; unsigned int nr_frags = skb_shinfo(skb)->nr_frags; int count = 0, size = skb_headlen(skb); for (;;) { count += i40e_txd_use_count(size); if (!nr_frags--) break; size = skb_frag_size(frag++); } return count; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Duyck84100.00%2100.00%
Total84100.00%2100.00%

/** * i40e_maybe_stop_tx - 1st level check for Tx stop conditions * @tx_ring: the ring to be checked * @size: the size buffer we want to assure is available * * Returns 0 if stop is not needed **/
static inline int i40e_maybe_stop_tx(struct i40e_ring *tx_ring, int size) { if (likely(I40E_DESC_UNUSED(tx_ring) >= size)) return 0; return __i40evf_maybe_stop_tx(tx_ring, size); }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Duyck38100.00%1100.00%
Total38100.00%1100.00%

/** * i40e_chk_linearize - Check if there are more than 8 fragments per packet * @skb: send buffer * @count: number of buffers used * * Note: Our HW can't scatter-gather more than 8 fragments to build * a packet on the wire and so we need to figure out the cases where we * need to linearize the skb. **/
static inline bool i40e_chk_linearize(struct sk_buff *skb, int count) { /* Both TSO and single send will work if count is less than 8 */ if (likely(count < I40E_MAX_BUFFER_TXD)) return false; if (skb_is_gso(skb)) return __i40evf_chk_linearize(skb); /* we can support up to 8 data buffers for a single send */ return count != I40E_MAX_BUFFER_TXD; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Duyck47100.00%2100.00%
Total47100.00%2100.00%

/** * i40e_rx_is_fcoe - returns true if the Rx packet type is FCoE * @ptype: the packet type field from Rx descriptor write-back **/
static inline bool i40e_rx_is_fcoe(u16 ptype) { return (ptype >= I40E_RX_PTYPE_L2_FCOE_PAY3) && (ptype <= I40E_RX_PTYPE_L2_FCOE_VFT_FCOTHER); }

Contributors

PersonTokensPropCommitsCommitProp
Jesse Brandeburg23100.00%1100.00%
Total23100.00%1100.00%

/** * txring_txq - Find the netdev Tx ring based on the i40e Tx ring * @ring: Tx ring to find the netdev equivalent of **/
static inline struct netdev_queue *txring_txq(const struct i40e_ring *ring) { return netdev_get_tx_queue(ring->netdev, ring->queue_index); }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Duyck27100.00%1100.00%
Total27100.00%1100.00%

#endif /* _I40E_TXRX_H_ */

Overall Contributors

PersonTokensPropCommitsCommitProp
Greg Rose61151.22%12.78%
Alexander Duyck24920.87%513.89%
Jesse Brandeburg16413.75%1233.33%
Anjali Singhai Jain736.12%1233.33%
Kiran Patil514.27%12.78%
Mitch A Williams322.68%38.33%
Jacob E Keller70.59%12.78%
Scott Peterson60.50%12.78%
Total1193100.00%36100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.