diff options
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/ieee802154.txt | 5 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 53 | ||||
| -rw-r--r-- | Documentation/networking/netlink_mmap.txt | 339 | ||||
| -rw-r--r-- | Documentation/networking/packet_mmap.txt | 368 | ||||
| -rw-r--r-- | Documentation/networking/stmmac.txt | 45 |
5 files changed, 756 insertions, 54 deletions
diff --git a/Documentation/networking/ieee802154.txt b/Documentation/networking/ieee802154.txt index 703cf4370c7..67a9cb259d4 100644 --- a/Documentation/networking/ieee802154.txt +++ b/Documentation/networking/ieee802154.txt @@ -71,8 +71,9 @@ submits skb to qdisc), so if you need something from that cb later, you should store info in the skb->data on your own. To hook the MLME interface you have to populate the ml_priv field of your -net_device with a pointer to struct ieee802154_mlme_ops instance. All fields are -required. +net_device with a pointer to struct ieee802154_mlme_ops instance. The fields +assoc_req, assoc_resp, disassoc_req, start_req, and scan_req are optional. +All other fields are required. We provide an example of simple HardMAC driver at drivers/ieee802154/fakehard.c diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index dc2dc87d255..f98ca633b52 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -29,7 +29,7 @@ route/max_size - INTEGER neigh/default/gc_thresh1 - INTEGER Minimum number of entries to keep. Garbage collector will not purge entries if there are fewer than this number. - Default: 256 + Default: 128 neigh/default/gc_thresh3 - INTEGER Maximum number of neighbor entries allowed. Increase this @@ -175,14 +175,6 @@ tcp_congestion_control - STRING is inherited. [see setsockopt(listenfd, SOL_TCP, TCP_CONGESTION, "name" ...) ] -tcp_cookie_size - INTEGER - Default size of TCP Cookie Transactions (TCPCT) option, that may be - overridden on a per socket basis by the TCPCT socket option. - Values greater than the maximum (16) are interpreted as the maximum. - Values greater than zero and less than the minimum (8) are interpreted - as the minimum. Odd values are interpreted as the next even value. - Default: 0 (off). - tcp_dsack - BOOLEAN Allows TCP to send "duplicate" SACKs. @@ -190,7 +182,9 @@ tcp_early_retrans - INTEGER Enable Early Retransmit (ER), per RFC 5827. ER lowers the threshold for triggering fast retransmit when the amount of outstanding data is small and when no previously unsent data can be transmitted (such - that limited transmit could be used). + that limited transmit could be used). Also controls the use of + Tail loss probe (TLP) that converts RTOs occuring due to tail + losses into fast recovery (draft-dukkipati-tcpm-tcp-loss-probe-01). Possible values: 0 disables ER 1 enables ER @@ -198,7 +192,9 @@ tcp_early_retrans - INTEGER by a fourth of RTT. This mitigates connection falsely recovers when network has a small degree of reordering (less than 3 packets). - Default: 2 + 3 enables delayed ER and TLP. + 4 enables TLP only. + Default: 3 tcp_ecn - INTEGER Control use of Explicit Congestion Notification (ECN) by TCP. @@ -229,36 +225,13 @@ tcp_fin_timeout - INTEGER Default: 60 seconds tcp_frto - INTEGER - Enables Forward RTO-Recovery (F-RTO) defined in RFC4138. + Enables Forward RTO-Recovery (F-RTO) defined in RFC5682. F-RTO is an enhanced recovery algorithm for TCP retransmission - timeouts. It is particularly beneficial in wireless environments - where packet loss is typically due to random radio interference - rather than intermediate router congestion. F-RTO is sender-side - only modification. Therefore it does not require any support from - the peer. - - If set to 1, basic version is enabled. 2 enables SACK enhanced - F-RTO if flow uses SACK. The basic version can be used also when - SACK is in use though scenario(s) with it exists where F-RTO - interacts badly with the packet counting of the SACK enabled TCP - flow. - -tcp_frto_response - INTEGER - When F-RTO has detected that a TCP retransmission timeout was - spurious (i.e, the timeout would have been avoided had TCP set a - longer retransmission timeout), TCP has several options what to do - next. Possible values are: - 0 Rate halving based; a smooth and conservative response, - results in halved cwnd and ssthresh after one RTT - 1 Very conservative response; not recommended because even - though being valid, it interacts poorly with the rest of - Linux TCP, halves cwnd and ssthresh immediately - 2 Aggressive response; undoes congestion control measures - that are now known to be unnecessary (ignoring the - possibility of a lost retransmission that would require - TCP to be more cautious), cwnd and ssthresh are restored - to the values prior timeout - Default: 0 (rate halving based) + timeouts. It is particularly beneficial in networks where the + RTT fluctuates (e.g., wireless). F-RTO is sender-side only + modification. It does not require any support from the peer. + + By default it's enabled with a non-zero value. 0 disables F-RTO. tcp_keepalive_time - INTEGER How often TCP sends out keepalive messages when keepalive is enabled. diff --git a/Documentation/networking/netlink_mmap.txt b/Documentation/networking/netlink_mmap.txt new file mode 100644 index 00000000000..1c2dab40962 --- /dev/null +++ b/Documentation/networking/netlink_mmap.txt @@ -0,0 +1,339 @@ +This file documents how to use memory mapped I/O with netlink. + +Author: Patrick McHardy <kaber@trash.net> + +Overview +-------- + +Memory mapped netlink I/O can be used to increase throughput and decrease +overhead of unicast receive and transmit operations. Some netlink subsystems +require high throughput, these are mainly the netfilter subsystems +nfnetlink_queue and nfnetlink_log, but it can also help speed up large +dump operations of f.i. the routing database. + +Memory mapped netlink I/O used two circular ring buffers for RX and TX which +are mapped into the processes address space. + +The RX ring is used by the kernel to directly construct netlink messages into +user-space memory without copying them as done with regular socket I/O, +additionally as long as the ring contains messages no recvmsg() or poll() +syscalls have to be issued by user-space to get more message. + +The TX ring is used to process messages directly from user-space memory, the +kernel processes all messages contained in the ring using a single sendmsg() +call. + +Usage overview +-------------- + +In order to use memory mapped netlink I/O, user-space needs three main changes: + +- ring setup +- conversion of the RX path to get messages from the ring instead of recvmsg() +- conversion of the TX path to construct messages into the ring + +Ring setup is done using setsockopt() to provide the ring parameters to the +kernel, then a call to mmap() to map the ring into the processes address space: + +- setsockopt(fd, SOL_NETLINK, NETLINK_RX_RING, ¶ms, sizeof(params)); +- setsockopt(fd, SOL_NETLINK, NETLINK_TX_RING, ¶ms, sizeof(params)); +- ring = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0) + +Usage of either ring is optional, but even if only the RX ring is used the +mapping still needs to be writable in order to update the frame status after +processing. + +Conversion of the reception path involves calling poll() on the file +descriptor, once the socket is readable the frames from the ring are +processsed in order until no more messages are available, as indicated by +a status word in the frame header. + +On kernel side, in order to make use of memory mapped I/O on receive, the +originating netlink subsystem needs to support memory mapped I/O, otherwise +it will use an allocated socket buffer as usual and the contents will be + copied to the ring on transmission, nullifying most of the performance gains. +Dumps of kernel databases automatically support memory mapped I/O. + +Conversion of the transmit path involves changing message contruction to +use memory from the TX ring instead of (usually) a buffer declared on the +stack and setting up the frame header approriately. Optionally poll() can +be used to wait for free frames in the TX ring. + +Structured and definitions for using memory mapped I/O are contained in +<linux/netlink.h>. + +RX and TX rings +---------------- + +Each ring contains a number of continous memory blocks, containing frames of +fixed size dependant on the parameters used for ring setup. + +Ring: [ block 0 ] + [ frame 0 ] + [ frame 1 ] + [ block 1 ] + [ frame 2 ] + [ frame 3 ] + ... + [ block n ] + [ frame 2 * n ] + [ frame 2 * n + 1 ] + +The blocks are only visible to the kernel, from the point of view of user-space +the ring just contains the frames in a continous memory zone. + +The ring parameters used for setting up the ring are defined as follows: + +struct nl_mmap_req { + unsigned int nm_block_size; + unsigned int nm_block_nr; + unsigned int nm_frame_size; + unsigned int nm_frame_nr; +}; + +Frames are grouped into blocks, where each block is a continous region of memory +and holds nm_block_size / nm_frame_size frames. The total number of frames in +the ring is nm_frame_nr. The following invariants hold: + +- frames_per_block = nm_block_size / nm_frame_size + +- nm_frame_nr = frames_per_block * nm_block_nr + +Some parameters are constrained, specifically: + +- nm_block_size must be a multiple of the architectures memory page size. + The getpagesize() function can be used to get the page size. + +- nm_frame_size must be equal or larger to NL_MMAP_HDRLEN, IOW a frame must be + able to hold at least the frame header + +- nm_frame_size must be smaller or equal to nm_block_size + +- nm_frame_size must be a multiple of NL_MMAP_MSG_ALIGNMENT + +- nm_frame_nr must equal the actual number of frames as specified above. + +When the kernel can't allocate phsyically continous memory for a ring block, +it will fall back to use physically discontinous memory. This might affect +performance negatively, in order to avoid this the nm_frame_size parameter +should be chosen to be as small as possible for the required frame size and +the number of blocks should be increased instead. + +Ring frames +------------ + +Each frames contain a frame header, consisting of a synchronization word and some +meta-data, and the message itself. + +Frame: [ header message ] + +The frame header is defined as follows: + +struct nl_mmap_hdr { + unsigned int nm_status; + unsigned int nm_len; + __u32 nm_group; + /* credentials */ + __u32 nm_pid; + __u32 nm_uid; + __u32 nm_gid; +}; + +- nm_status is used for synchronizing processing between the kernel and user- + space and specifies ownership of the frame as well as the operation to perform + +- nm_len contains the length of the message contained in the data area + +- nm_group specified the destination multicast group of message + +- nm_pid, nm_uid and nm_gid contain the netlink pid, UID and GID of the sending + process. These values correspond to the data available using SOCK_PASSCRED in + the SCM_CREDENTIALS cmsg. + +The possible values in the status word are: + +- NL_MMAP_STATUS_UNUSED: + RX ring: frame belongs to the kernel and contains no message + for user-space. Approriate action is to invoke poll() + to wait for new messages. + + TX ring: frame belongs to user-space and can be used for + message construction. + +- NL_MMAP_STATUS_RESERVED: + RX ring only: frame is currently used by the kernel for message + construction and contains no valid message yet. + Appropriate action is to invoke poll() to wait for + new messages. + +- NL_MMAP_STATUS_VALID: + RX ring: frame contains a valid message. Approriate action is + to process the message and release the frame back to + the kernel by setting the status to + NL_MMAP_STATUS_UNUSED or queue the frame by setting the + status to NL_MMAP_STATUS_SKIP. + + TX ring: the frame contains a valid message from user-space to + be processed by the kernel. After completing processing + the kernel will release the frame back to user-space by + setting the status to NL_MMAP_STATUS_UNUSED. + +- NL_MMAP_STATUS_COPY: + RX ring only: a message is ready to be processed but could not be + stored in the ring, either because it exceeded the + frame size or because the originating subsystem does + not support memory mapped I/O. Appropriate action is + to invoke recvmsg() to receive the message and release + the frame back to the kernel by setting the status to + NL_MMAP_STATUS_UNUSED. + +- NL_MMAP_STATUS_SKIP: + RX ring only: user-space queued the message for later processing, but + processed some messages following it in the ring. The + kernel should skip this frame when looking for unused + frames. + +The data area of a frame begins at a offset of NL_MMAP_HDRLEN relative to the +frame header. + +TX limitations +-------------- + +Kernel processing usually involves validation of the message received by +user-space, then processing its contents. The kernel must assure that +userspace is not able to modify the message contents after they have been +validated. In order to do so, the message is copied from the ring frame +to an allocated buffer if either of these conditions is false: + +- only a single mapping of the ring exists +- the file descriptor is not shared between processes + +This means that for threaded programs, the kernel will fall back to copying. + +Example +------- + +Ring setup: + + unsigned int block_size = 16 * getpagesize(); + struct nl_mmap_req req = { + .nm_block_size = block_size, + .nm_block_nr = 64, + .nm_frame_size = 16384, + .nm_frame_nr = 64 * block_size / 16384, + }; + unsigned int ring_size; + void *rx_ring, *tx_ring; + + /* Configure ring parameters */ + if (setsockopt(fd, NETLINK_RX_RING, &req, sizeof(req)) < 0) + exit(1); + if (setsockopt(fd, NETLINK_TX_RING, &req, sizeof(req)) < 0) + exit(1) + + /* Calculate size of each invididual ring */ + ring_size = req.nm_block_nr * req.nm_block_size; + + /* Map RX/TX rings. The TX ring is located after the RX ring */ + rx_ring = mmap(NULL, 2 * ring_size, PROT_READ | PROT_WRITE, + MAP_SHARED, fd, 0); + if ((long)rx_ring == -1L) + exit(1); + tx_ring = rx_ring + ring_size: + +Message reception: + +This example assumes some ring parameters of the ring setup are available. + + unsigned int frame_offset = 0; + struct nl_mmap_hdr *hdr; + struct nlmsghdr *nlh; + unsigned char buf[16384]; + ssize_t len; + + while (1) { + struct pollfd pfds[1]; + + pfds[0].fd = fd; + pfds[0].events = POLLIN | POLLERR; + pfds[0].revents = 0; + + if (poll(pfds, 1, -1) < 0 && errno != -EINTR) + exit(1); + + /* Check for errors. Error handling omitted */ + if (pfds[0].revents & POLLERR) + <handle error> + + /* If no new messages, poll again */ + if (!(pfds[0].revents & POLLIN)) + continue; + + /* Process all frames */ + while (1) { + /* Get next frame header */ + hdr = rx_ring + frame_offset; + + if (hdr->nm_status == NL_MMAP_STATUS_VALID) + /* Regular memory mapped frame */ + nlh = (void *hdr) + NL_MMAP_HDRLEN; + len = hdr->nm_len; + + /* Release empty message immediately. May happen + * on error during message construction. + */ + if (len == 0) + goto release; + } else if (hdr->nm_status == NL_MMAP_STATUS_COPY) { + /* Frame queued to socket receive queue */ + len = recv(fd, buf, sizeof(buf), MSG_DONTWAIT); + if (len <= 0) + break; + nlh = buf; + } else + /* No more messages to process, continue polling */ + break; + + process_msg(nlh); +release: + /* Release frame back to the kernel */ + hdr->nm_status = NL_MMAP_STATUS_UNUSED; + + /* Advance frame offset to next frame */ + frame_offset = (frame_offset + frame_size) % ring_size; + } + } + +Message transmission: + +This example assumes some ring parameters of the ring setup are available. +A single message is constructed and transmitted, to send multiple messages +at once they would be constructed in consecutive frames before a final call +to sendto(). + + unsigned int frame_offset = 0; + struct nl_mmap_hdr *hdr; + struct nlmsghdr *nlh; + struct sockaddr_nl addr = { + .nl_family = AF_NETLINK, + }; + + hdr = tx_ring + frame_offset; + if (hdr->nm_status != NL_MMAP_STATUS_UNUSED) + /* No frame available. Use poll() to avoid. */ + exit(1); + + nlh = (void *)hdr + NL_MMAP_HDRLEN; + + /* Build message */ + build_message(nlh); + + /* Fill frame header: length and status need to be set */ + hdr->nm_len = nlh->nlmsg_len; + hdr->nm_status = NL_MMAP_STATUS_VALID; + + if (sendto(fd, NULL, 0, 0, &addr, sizeof(addr)) < 0) + exit(1); + + /* Advance frame offset to next frame */ + frame_offset = (frame_offset + frame_size) % ring_size; diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt index 94444b152fb..23dd80e82b8 100644 --- a/Documentation/networking/packet_mmap.txt +++ b/Documentation/networking/packet_mmap.txt @@ -685,14 +685,342 @@ int main(int argc, char **argp) } ------------------------------------------------------------------------------- ++ AF_PACKET TPACKET_V3 example +------------------------------------------------------------------------------- + +AF_PACKET's TPACKET_V3 ring buffer can be configured to use non-static frame +sizes by doing it's own memory management. It is based on blocks where polling +works on a per block basis instead of per ring as in TPACKET_V2 and predecessor. + +It is said that TPACKET_V3 brings the following benefits: + *) ~15 - 20% reduction in CPU-usage + *) ~20% increase in packet capture rate + *) ~2x increase in packet density + *) Port aggregation analysis + *) Non static frame size to capture entire packet payload + +So it seems to be a good candidate to be used with packet fanout. + +Minimal example code by Daniel Borkmann based on Chetan Loke's lolpcap (compile +it with gcc -Wall -O2 blob.c, and try things like "./a.out eth0", etc.): + +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> +#include <assert.h> +#include <net/if.h> +#include <arpa/inet.h> +#include <netdb.h> +#include <poll.h> +#include <unistd.h> +#include <signal.h> +#include <inttypes.h> +#include <sys/socket.h> +#include <sys/mman.h> +#include <linux/if_packet.h> +#include <linux/if_ether.h> +#include <linux/ip.h> + +#define BLOCK_SIZE (1 << 22) +#define FRAME_SIZE 2048 + +#define NUM_BLOCKS 64 +#define NUM_FRAMES ((BLOCK_SIZE * NUM_BLOCKS) / FRAME_SIZE) + +#define BLOCK_RETIRE_TOV_IN_MS 64 +#define BLOCK_PRIV_AREA_SZ 13 + +#define ALIGN_8(x) (((x) + 8 - 1) & ~(8 - 1)) + +#define BLOCK_STATUS(x) ((x)->h1.block_status) +#define BLOCK_NUM_PKTS(x) ((x)->h1.num_pkts) +#define BLOCK_O2FP(x) ((x)->h1.offset_to_first_pkt) +#define BLOCK_LEN(x) ((x)->h1.blk_len) +#define BLOCK_SNUM(x) ((x)->h1.seq_num) +#define BLOCK_O2PRIV(x) ((x)->offset_to_priv) +#define BLOCK_PRIV(x) ((void *) ((uint8_t *) (x) + BLOCK_O2PRIV(x))) +#define BLOCK_HDR_LEN (ALIGN_8(sizeof(struct block_desc))) +#define BLOCK_PLUS_PRIV(sz_pri) (BLOCK_HDR_LEN + ALIGN_8((sz_pri))) + +#ifndef likely +# define likely(x) __builtin_expect(!!(x), 1) +#endif +#ifndef unlikely +# define unlikely(x) __builtin_expect(!!(x), 0) +#endif + +struct block_desc { + uint32_t version; + uint32_t offset_to_priv; + struct tpacket_hdr_v1 h1; +}; + +struct ring { + struct iovec *rd; + uint8_t *map; + struct tpacket_req3 req; +}; + +static unsigned long packets_total = 0, bytes_total = 0; +static sig_atomic_t sigint = 0; + +void sighandler(int num) +{ + sigint = 1; +} + +static int setup_socket(struct ring *ring, char *netdev) +{ + int err, i, fd, v = TPACKET_V3; + struct sockaddr_ll ll; + + fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL)); + if (fd < 0) { + perror("socket"); + exit(1); + } + + err = setsockopt(fd, SOL_PACKET, PACKET_VERSION, &v, sizeof(v)); + if (err < 0) { + perror("setsockopt"); + exit(1); + } + + memset(&ring->req, 0, sizeof(ring->req)); + ring->req.tp_block_size = BLOCK_SIZE; + ring->req.tp_frame_size = FRAME_SIZE; + ring->req.tp_block_nr = NUM_BLOCKS; + ring->req.tp_frame_nr = NUM_FRAMES; + ring->req.tp_retire_blk_tov = BLOCK_RETIRE_TOV_IN_MS; + ring->req.tp_sizeof_priv = BLOCK_PRIV_AREA_SZ; + ring->req.tp_feature_req_word |= TP_FT_REQ_FILL_RXHASH; + + err = setsockopt(fd, SOL_PACKET, PACKET_RX_RING, &ring->req, + sizeof(ring->req)); + if (err < 0) { + perror("setsockopt"); + exit(1); + } + + ring->map = mmap(NULL, ring->req.tp_block_size * ring->req.tp_block_nr, + PROT_READ | PROT_WRITE, MAP_SHARED | MAP_LOCKED, + fd, 0); + if (ring->map == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + ring->rd = malloc(ring->req.tp_block_nr * sizeof(*ring->rd)); + assert(ring->rd); + for (i = 0; i < ring->req.tp_block_nr; ++i) { + ring->rd[i].iov_base = ring->map + (i * ring->req.tp_block_size); + ring->rd[i].iov_len = ring->req.tp_block_size; + } + + memset(&ll, 0, sizeof(ll)); + ll.sll_family = PF_PACKET; + ll.sll_protocol = htons(ETH_P_ALL); + ll.sll_ifindex = if_nametoindex(netdev); + ll.sll_hatype = 0; + ll.sll_pkttype = 0; + ll.sll_halen = 0; + + err = bind(fd, (struct sockaddr *) &ll, sizeof(ll)); + if (err < 0) { + perror("bind"); + exit(1); + } + + return fd; +} + +#ifdef __checked +static uint64_t prev_block_seq_num = 0; + +void assert_block_seq_num(struct block_desc *pbd) +{ + if (unlikely(prev_block_seq_num + 1 != BLOCK_SNUM(pbd))) { + printf("prev_block_seq_num:%"PRIu64", expected seq:%"PRIu64" != " + "actual seq:%"PRIu64"\n", prev_block_seq_num, + prev_block_seq_num + 1, (uint64_t) BLOCK_SNUM(pbd)); + exit(1); + } + + prev_block_seq_num = BLOCK_SNUM(pbd); +} + +static void assert_block_len(struct block_desc *pbd, uint32_t bytes, int block_num) +{ + if (BLOCK_NUM_PKTS(pbd)) { + if (unlikely(bytes != BLOCK_LEN(pbd))) { + printf("block:%u with %upackets, expected len:%u != actual len:%u\n", + block_num, BLOCK_NUM_PKTS(pbd), bytes, BLOCK_LEN(pbd)); + exit(1); + } + } else { + if (unlikely(BLOCK_LEN(pbd) != BLOCK_PLUS_PRIV(BLOCK_PRIV_AREA_SZ))) { + printf("block:%u, expected len:%lu != actual len:%u\n", + block_num, BLOCK_HDR_LEN, BLOCK_LEN(pbd)); + exit(1); + } + } +} + +static void assert_block_header(struct block_desc *pbd, const int block_num) +{ + uint32_t block_status = BLOCK_STATUS(pbd); + + if (unlikely((block_status & TP_STATUS_USER) == 0)) { + printf("block:%u, not in TP_STATUS_USER\n", block_num); + exit(1); + } + + assert_block_seq_num(pbd); +} +#else +static inline void assert_block_header(struct block_desc *pbd, const int block_num) +{ +} +static void assert_block_len(struct block_desc *pbd, uint32_t bytes, int block_num) +{ +} +#endif + +static void display(struct tpacket3_hdr *ppd) +{ + struct ethhdr *eth = (struct ethhdr *) ((uint8_t *) ppd + ppd->tp_mac); + struct iphdr *ip = (struct iphdr *) ((uint8_t *) eth + ETH_HLEN); + + if (eth->h_proto == htons(ETH_P_IP)) { + struct sockaddr_in ss, sd; + char sbuff[NI_MAXHOST], dbuff[NI_MAXHOST]; + + memset(&ss, 0, sizeof(ss)); + ss.sin_family = PF_INET; + ss.sin_addr.s_addr = ip->saddr; + getnameinfo((struct sockaddr *) &ss, sizeof(ss), + sbuff, sizeof(sbuff), NULL, 0, NI_NUMERICHOST); + + memset(&sd, 0, sizeof(sd)); + sd.sin_family = PF_INET; + sd.sin_addr.s_addr = ip->daddr; + getnameinfo((struct sockaddr *) &sd, sizeof(sd), + dbuff, sizeof(dbuff), NULL, 0, NI_NUMERICHOST); + + printf("%s -> %s, ", sbuff, dbuff); + } + + printf("rxhash: 0x%x\n", ppd->hv1.tp_rxhash); +} + +static void walk_block(struct block_desc *pbd, const int block_num) +{ + int num_pkts = BLOCK_NUM_PKTS(pbd), i; + unsigned long bytes = 0; + unsigned long bytes_with_padding = BLOCK_PLUS_PRIV(BLOCK_PRIV_AREA_SZ); + struct tpacket3_hdr *ppd; + + assert_block_header(pbd, block_num); + + ppd = (struct tpacket3_hdr *) ((uint8_t *) pbd + BLOCK_O2FP(pbd)); + for (i = 0; i < num_pkts; ++i) { + bytes += ppd->tp_snaplen; + if (ppd->tp_next_offset) + bytes_with_padding += ppd->tp_next_offset; + else + bytes_with_padding += ALIGN_8(ppd->tp_snaplen + ppd->tp_mac); + + display(ppd); + + ppd = (struct tpacket3_hdr *) ((uint8_t *) ppd + ppd->tp_next_offset); + __sync_synchronize(); + } + + assert_block_len(pbd, bytes_with_padding, block_num); + + packets_total += num_pkts; + bytes_total += bytes; +} + +void flush_block(struct block_desc *pbd) +{ + BLOCK_STATUS(pbd) = TP_STATUS_KERNEL; + __sync_synchronize(); +} + +static void teardown_socket(struct ring *ring, int fd) +{ + munmap(ring->map, ring->req.tp_block_size * ring->req.tp_block_nr); + free(ring->rd); + close(fd); +} + +int main(int argc, char **argp) +{ + int fd, err; + socklen_t len; + struct ring ring; + struct pollfd pfd; + unsigned int block_num = 0; + struct block_desc *pbd; + struct tpacket_stats_v3 stats; + + if (argc != 2) { + fprintf(stderr, "Usage: %s INTERFACE\n", argp[0]); + return EXIT_FAILURE; + } + + signal(SIGINT, sighandler); + + memset(&ring, 0, sizeof(ring)); + fd = setup_socket(&ring, argp[argc - 1]); + assert(fd > 0); + + memset(&pfd, 0, sizeof(pfd)); + pfd.fd = fd; + pfd.events = POLLIN | POLLERR; + pfd.revents = 0; + + while (likely(!sigint)) { + pbd = (struct block_desc *) ring.rd[block_num].iov_base; +retry_block: + if ((BLOCK_STATUS(pbd) & TP_STATUS_USER) == 0) { + poll(&pfd, 1, -1); + goto retry_block; + } + + walk_block(pbd, block_num); + flush_block(pbd); + block_num = (block_num + 1) % NUM_BLOCKS; + } + + len = sizeof(stats); + err = getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, &stats, &len); + if (err < 0) { + perror("getsockopt"); + exit(1); + } + + fflush(stdout); + printf("\nReceived %u packets, %lu bytes, %u dropped, freeze_q_cnt: %u\n", + stats.tp_packets, bytes_total, stats.tp_drops, + stats.tp_freeze_q_cnt); + + teardown_socket(&ring, fd); + return 0; +} + +------------------------------------------------------------------------------- + PACKET_TIMESTAMP ------------------------------------------------------------------------------- The PACKET_TIMESTAMP setting determines the source of the timestamp in -the packet meta information. If your NIC is capable of timestamping -packets in hardware, you can request those hardware timestamps to used. -Note: you may need to enable the generation of hardware timestamps with -SIOCSHWTSTAMP. +the packet meta information for mmap(2)ed RX_RING and TX_RINGs. If your +NIC is capable of timestamping packets in hardware, you can request those +hardware timestamps to be used. Note: you may need to enable the generation +of hardware timestamps with SIOCSHWTSTAMP (see related information from +Documentation/networking/timestamping.txt). PACKET_TIMESTAMP accepts the same integer bit field as SO_TIMESTAMPING. However, only the SOF_TIMESTAMPING_SYS_HARDWARE @@ -704,8 +1032,36 @@ SOF_TIMESTAMPING_RAW_HARDWARE if both bits are set. req |= SOF_TIMESTAMPING_SYS_HARDWARE; setsockopt(fd, SOL_PACKET, PACKET_TIMESTAMP, (void *) &req, sizeof(req)) -If PACKET_TIMESTAMP is not set, a software timestamp generated inside -the networking stack is used (the behavior before this setting was added). +For the mmap(2)ed ring buffers, such timestamps are stored in the +tpacket{,2,3}_hdr structure's tp_sec and tp_{n,u}sec members. To determine +what kind of timestamp has been reported, the tp_status field is binary |'ed +with the following possible bits ... + + TP_STATUS_TS_SYS_HARDWARE + TP_STATUS_TS_RAW_HARDWARE + TP_STATUS_TS_SOFTWARE + +... that are equivalent to its SOF_TIMESTAMPING_* counterparts. For the +RX_RING, if none of those 3 are set (i.e. PACKET_TIMESTAMP is not set), +then this means that a software fallback was invoked *within* PF_PACKET's +processing code (less precise). + +Getting timestamps for the TX_RING works as follows: i) fill the ring frames, +ii) call sendto() e.g. in blocking mode, iii) wait for status of relevant +frames to be updated resp. the frame handed over to the application, iv) walk +through the frames to pick up the individual hw/sw timestamps. + +Only (!) if transmit timestamping is enabled, then these bits are combined +with binary | with TP_STATUS_AVAILABLE, so you must check for that in your +application (e.g. !(tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING)) +in a first step to see if the frame belongs to the application, and then +one can extract the type of timestamp in a second step from tp_status)! + +If you don't care about them, thus having it disabled, checking for +TP_STATUS_AVAILABLE resp. TP_STATUS_WRONG_FORMAT is sufficient. If in the +TX_RING part only TP_STATUS_AVAILABLE is set, then the tp_sec and tp_{n,u}sec +members do not contain a valid value. For TX_RINGs, by default no timestamp +is generated! See include/linux/net_tstamp.h and Documentation/networking/timestamping for more information on hardware timestamps. diff --git a/Documentation/networking/stmmac.txt b/Documentation/networking/stmmac.txt index f9fa6db40a5..654d2e55c8c 100644 --- a/Documentation/networking/stmmac.txt +++ b/Documentation/networking/stmmac.txt @@ -1,6 +1,6 @@ STMicroelectronics 10/100/1000 Synopsys Ethernet driver -Copyright (C) 2007-2010 STMicroelectronics Ltd +Copyright (C) 2007-2013 STMicroelectronics Ltd Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> This is the driver for the MAC 10/100/1000 on-chip Ethernet controllers @@ -10,7 +10,7 @@ Currently this network device driver is for all STM embedded MAC/GMAC (i.e. 7xxx/5xxx SoCs), SPEAr (arm), Loongson1B (mips) and XLINX XC2V3000 FF1152AMT0221 D1215994A VIRTEX FPGA board. -DWC Ether MAC 10/100/1000 Universal version 3.60a (and older) and DWC Ether +DWC Ether MAC 10/100/1000 Universal version 3.70a (and older) and DWC Ether MAC 10/100 Universal version 4.0 have been used for developing this driver. This driver supports both the platform bus and PCI. @@ -32,6 +32,8 @@ The kernel configuration option is STMMAC_ETH: watchdog: transmit timeout (in milliseconds); flow_ctrl: Flow control ability [on/off]; pause: Flow Control Pause Time; + eee_timer: tx EEE timer; + chain_mode: select chain mode instead of ring. 3) Command line options Driver parameters can be also passed in command line by using: @@ -164,12 +166,12 @@ Where: o bus_setup: perform HW setup of the bus. For example, on some ST platforms this field is used to configure the AMBA bridge to generate more efficient STBus traffic. - o init/exit: callbacks used for calling a custom initialisation; + o init/exit: callbacks used for calling a custom initialization; this is sometime necessary on some platforms (e.g. ST boxes) where the HW needs to have set some PIO lines or system cfg registers. o custom_cfg/custom_data: this is a custom configuration that can be passed - while initialising the resources. + while initializing the resources. o bsp_priv: another private poiter. For MDIO bus The we have: @@ -273,6 +275,8 @@ reset procedure etc). o norm_desc.c: functions for handling normal descriptors; o chain_mode.c/ring_mode.c:: functions to manage RING/CHAINED modes; o mmc_core.c/mmc.h: Management MAC Counters; + o stmmac_hwtstamp.c: HW timestamp support for PTP + o stmmac_ptp.c: PTP 1588 clock 5) Debug Information @@ -326,6 +330,35 @@ To enter in Tx LPI mode the driver needs to have a software timer that enable and disable the LPI mode when there is nothing to be transmitted. -7) TODO: +7) Extended descriptors +The extended descriptors give us information about the receive Ethernet payload +when it is carrying PTP packets or TCP/UDP/ICMP over IP. +These are not available on GMAC Synopsys chips older than the 3.50. +At probe time the driver will decide if these can be actually used. +This support also is mandatory for PTPv2 because the extra descriptors 6 and 7 +are used for saving the hardware timestamps. + +8) Precision Time Protocol (PTP) +The driver supports the IEEE 1588-2002, Precision Time Protocol (PTP), +which enables precise synchronization of clocks in measurement and +control systems implemented with technologies such as network +communication. + +In addition to the basic timestamp features mentioned in IEEE 1588-2002 +Timestamps, new GMAC cores support the advanced timestamp features. +IEEE 1588-2008 that can be enabled when configure the Kernel. + +9) SGMII/RGMII supports +New GMAC devices provide own way to manage RGMII/SGMII. +This information is available at run-time by looking at the +HW capability register. This means that the stmmac can manage +auto-negotiation and link status w/o using the PHYLIB stuff +In fact, the HW provides a subset of extended registers to +restart the ANE, verify Full/Half duplex mode and Speed. +Also thanks to these registers it is possible to look at the +Auto-negotiated Link Parter Ability. + +10) TODO: o XGMAC is not supported. - o Add the PTP - precision time protocol + o Complete the TBI & RTBI support. + o extened VLAN support for 3.70a SYNP GMAC. |