From 5ebfb4cc3048380b43506ffc71b9cf8b83128989 Mon Sep 17 00:00:00 2001 From: Coco Li Date: Thu, 5 Aug 2021 07:36:41 +0000 Subject: selftests/net: toeplitz test To verify that this hash implements the Toeplitz hash function. Additionally, provide a script toeplitz.sh to run the test in loopback mode on a networking device of choice (see setup_loopback.sh). Since the script modifies the NIC setup, it will not be run by selftests automatically. Tested: ./toeplitz.sh -i eth0 -irq_prefix -t -6 carrier ready rxq 0: cpu 14 rxq 1: cpu 20 rxq 2: cpu 17 rxq 3: cpu 23 cpu 14: rx_hash 0x69103ebc [saddr fda8::2 daddr fda8::1 sport 58938 dport 8000] OK rxq 0 (cpu 14) ... cpu 20: rx_hash 0x257118b9 [saddr fda8::2 daddr fda8::1 sport 59258 dport 8000] OK rxq 1 (cpu 20) count: pass=111 nohash=0 fail=0 Test Succeeded! Signed-off-by: Coco Li Reviewed-by: Willem de Bruijn Signed-off-by: David S. Miller --- tools/testing/selftests/net/toeplitz.c | 585 +++++++++++++++++++++++++++++++++ 1 file changed, 585 insertions(+) create mode 100644 tools/testing/selftests/net/toeplitz.c (limited to 'tools/testing/selftests/net/toeplitz.c') diff --git a/tools/testing/selftests/net/toeplitz.c b/tools/testing/selftests/net/toeplitz.c new file mode 100644 index 000000000000..710ac956bdb3 --- /dev/null +++ b/tools/testing/selftests/net/toeplitz.c @@ -0,0 +1,585 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Toeplitz test + * + * 1. Read packets and their rx_hash using PF_PACKET/TPACKET_V3 + * 2. Compute the rx_hash in software based on the packet contents + * 3. Compare the two + * + * Optionally, either '-C $rx_irq_cpu_list' or '-r $rps_bitmap' may be given. + * + * If '-C $rx_irq_cpu_list' is given, also + * + * 4. Identify the cpu on which the packet arrived with PACKET_FANOUT_CPU + * 5. Compute the rxqueue that RSS would select based on this rx_hash + * 6. Using the $rx_irq_cpu_list map, identify the arriving cpu based on rxq irq + * 7. Compare the cpus from 4 and 6 + * + * Else if '-r $rps_bitmap' is given, also + * + * 4. Identify the cpu on which the packet arrived with PACKET_FANOUT_CPU + * 5. Compute the cpu that RPS should select based on rx_hash and $rps_bitmap + * 6. Compare the cpus from 4 and 5 + */ + +#define _GNU_SOURCE + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TOEPLITZ_KEY_MIN_LEN 40 +#define TOEPLITZ_KEY_MAX_LEN 60 + +#define TOEPLITZ_STR_LEN(K) (((K) * 3) - 1) /* hex encoded: AA:BB:CC:...:ZZ */ +#define TOEPLITZ_STR_MIN_LEN TOEPLITZ_STR_LEN(TOEPLITZ_KEY_MIN_LEN) +#define TOEPLITZ_STR_MAX_LEN TOEPLITZ_STR_LEN(TOEPLITZ_KEY_MAX_LEN) + +#define FOUR_TUPLE_MAX_LEN ((sizeof(struct in6_addr) * 2) + (sizeof(uint16_t) * 2)) + +#define RSS_MAX_CPUS (1 << 16) /* real constraint is PACKET_FANOUT_MAX */ + +#define RPS_MAX_CPUS 16UL /* must be a power of 2 */ + +/* configuration options (cmdline arguments) */ +static uint16_t cfg_dport = 8000; +static int cfg_family = AF_INET6; +static char *cfg_ifname = "eth0"; +static int cfg_num_queues; +static int cfg_num_rps_cpus; +static bool cfg_sink; +static int cfg_type = SOCK_STREAM; +static int cfg_timeout_msec = 1000; +static bool cfg_verbose; + +/* global vars */ +static int num_cpus; +static int ring_block_nr; +static int ring_block_sz; + +/* stats */ +static int frames_received; +static int frames_nohash; +static int frames_error; + +#define log_verbose(args...) do { if (cfg_verbose) fprintf(stderr, args); } while (0) + +/* tpacket ring */ +struct ring_state { + int fd; + char *mmap; + int idx; + int cpu; +}; + +static unsigned int rx_irq_cpus[RSS_MAX_CPUS]; /* map from rxq to cpu */ +static int rps_silo_to_cpu[RPS_MAX_CPUS]; +static unsigned char toeplitz_key[TOEPLITZ_KEY_MAX_LEN]; +static struct ring_state rings[RSS_MAX_CPUS]; + +static inline uint32_t toeplitz(const unsigned char *four_tuple, + const unsigned char *key) +{ + int i, bit, ret = 0; + uint32_t key32; + + key32 = ntohl(*((uint32_t *)key)); + key += 4; + + for (i = 0; i < FOUR_TUPLE_MAX_LEN; i++) { + for (bit = 7; bit >= 0; bit--) { + if (four_tuple[i] & (1 << bit)) + ret ^= key32; + + key32 <<= 1; + key32 |= !!(key[0] & (1 << bit)); + } + key++; + } + + return ret; +} + +/* Compare computed cpu with arrival cpu from packet_fanout_cpu */ +static void verify_rss(uint32_t rx_hash, int cpu) +{ + int queue = rx_hash % cfg_num_queues; + + log_verbose(" rxq %d (cpu %d)", queue, rx_irq_cpus[queue]); + if (rx_irq_cpus[queue] != cpu) { + log_verbose(". error: rss cpu mismatch (%d)", cpu); + frames_error++; + } +} + +static void verify_rps(uint64_t rx_hash, int cpu) +{ + int silo = (rx_hash * cfg_num_rps_cpus) >> 32; + + log_verbose(" silo %d (cpu %d)", silo, rps_silo_to_cpu[silo]); + if (rps_silo_to_cpu[silo] != cpu) { + log_verbose(". error: rps cpu mismatch (%d)", cpu); + frames_error++; + } +} + +static void log_rxhash(int cpu, uint32_t rx_hash, + const char *addrs, int addr_len) +{ + char saddr[INET6_ADDRSTRLEN], daddr[INET6_ADDRSTRLEN]; + uint16_t *ports; + + if (!inet_ntop(cfg_family, addrs, saddr, sizeof(saddr)) || + !inet_ntop(cfg_family, addrs + addr_len, daddr, sizeof(daddr))) + error(1, 0, "address parse error"); + + ports = (void *)addrs + (addr_len * 2); + log_verbose("cpu %d: rx_hash 0x%08x [saddr %s daddr %s sport %02hu dport %02hu]", + cpu, rx_hash, saddr, daddr, + ntohs(ports[0]), ntohs(ports[1])); +} + +/* Compare computed rxhash with rxhash received from tpacket_v3 */ +static void verify_rxhash(const char *pkt, uint32_t rx_hash, int cpu) +{ + unsigned char four_tuple[FOUR_TUPLE_MAX_LEN] = {0}; + uint32_t rx_hash_sw; + const char *addrs; + int addr_len; + + if (cfg_family == AF_INET) { + addr_len = sizeof(struct in_addr); + addrs = pkt + offsetof(struct iphdr, saddr); + } else { + addr_len = sizeof(struct in6_addr); + addrs = pkt + offsetof(struct ip6_hdr, ip6_src); + } + + memcpy(four_tuple, addrs, (addr_len * 2) + (sizeof(uint16_t) * 2)); + rx_hash_sw = toeplitz(four_tuple, toeplitz_key); + + if (cfg_verbose) + log_rxhash(cpu, rx_hash, addrs, addr_len); + + if (rx_hash != rx_hash_sw) { + log_verbose(" != expected 0x%x\n", rx_hash_sw); + frames_error++; + return; + } + + log_verbose(" OK"); + if (cfg_num_queues) + verify_rss(rx_hash, cpu); + else if (cfg_num_rps_cpus) + verify_rps(rx_hash, cpu); + log_verbose("\n"); +} + +static char *recv_frame(const struct ring_state *ring, char *frame) +{ + struct tpacket3_hdr *hdr = (void *)frame; + + if (hdr->hv1.tp_rxhash) + verify_rxhash(frame + hdr->tp_net, hdr->hv1.tp_rxhash, + ring->cpu); + else + frames_nohash++; + + return frame + hdr->tp_next_offset; +} + +/* A single TPACKET_V3 block can hold multiple frames */ +static void recv_block(struct ring_state *ring) +{ + struct tpacket_block_desc *block; + char *frame; + int i; + + block = (void *)(ring->mmap + ring->idx * ring_block_sz); + if (!(block->hdr.bh1.block_status & TP_STATUS_USER)) + return; + + frame = (char *)block; + frame += block->hdr.bh1.offset_to_first_pkt; + + for (i = 0; i < block->hdr.bh1.num_pkts; i++) { + frame = recv_frame(ring, frame); + frames_received++; + } + + block->hdr.bh1.block_status = TP_STATUS_KERNEL; + ring->idx = (ring->idx + 1) % ring_block_nr; +} + +/* simple test: sleep once unconditionally and then process all rings */ +static void process_rings(void) +{ + int i; + + usleep(1000 * cfg_timeout_msec); + + for (i = 0; i < num_cpus; i++) + recv_block(&rings[i]); + + fprintf(stderr, "count: pass=%u nohash=%u fail=%u\n", + frames_received - frames_nohash - frames_error, + frames_nohash, frames_error); +} + +static char *setup_ring(int fd) +{ + struct tpacket_req3 req3 = {0}; + void *ring; + + req3.tp_retire_blk_tov = cfg_timeout_msec; + req3.tp_feature_req_word = TP_FT_REQ_FILL_RXHASH; + + req3.tp_frame_size = 2048; + req3.tp_frame_nr = 1 << 10; + req3.tp_block_nr = 2; + + req3.tp_block_size = req3.tp_frame_size * req3.tp_frame_nr; + req3.tp_block_size /= req3.tp_block_nr; + + if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, &req3, sizeof(req3))) + error(1, errno, "setsockopt PACKET_RX_RING"); + + ring_block_sz = req3.tp_block_size; + ring_block_nr = req3.tp_block_nr; + + ring = mmap(0, req3.tp_block_size * req3.tp_block_nr, + PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_LOCKED | MAP_POPULATE, fd, 0); + if (ring == MAP_FAILED) + error(1, 0, "mmap failed"); + + return ring; +} + +static void __set_filter(int fd, int off_proto, uint8_t proto, int off_dport) +{ + struct sock_filter filter[] = { + BPF_STMT(BPF_LD + BPF_B + BPF_ABS, SKF_AD_OFF + SKF_AD_PKTTYPE), + BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, PACKET_HOST, 0, 4), + BPF_STMT(BPF_LD + BPF_B + BPF_ABS, off_proto), + BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, proto, 0, 2), + BPF_STMT(BPF_LD + BPF_H + BPF_ABS, off_dport), + BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, cfg_dport, 1, 0), + BPF_STMT(BPF_RET + BPF_K, 0), + BPF_STMT(BPF_RET + BPF_K, 0xFFFF), + }; + struct sock_fprog prog = {}; + + prog.filter = filter; + prog.len = sizeof(filter) / sizeof(struct sock_filter); + if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &prog, sizeof(prog))) + error(1, errno, "setsockopt filter"); +} + +/* filter on transport protocol and destination port */ +static void set_filter(int fd) +{ + const int off_dport = offsetof(struct tcphdr, dest); /* same for udp */ + uint8_t proto; + + proto = cfg_type == SOCK_STREAM ? IPPROTO_TCP : IPPROTO_UDP; + if (cfg_family == AF_INET) + __set_filter(fd, offsetof(struct iphdr, protocol), proto, + sizeof(struct iphdr) + off_dport); + else + __set_filter(fd, offsetof(struct ip6_hdr, ip6_nxt), proto, + sizeof(struct ip6_hdr) + off_dport); +} + +/* drop everything: used temporarily during setup */ +static void set_filter_null(int fd) +{ + struct sock_filter filter[] = { + BPF_STMT(BPF_RET + BPF_K, 0), + }; + struct sock_fprog prog = {}; + + prog.filter = filter; + prog.len = sizeof(filter) / sizeof(struct sock_filter); + if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &prog, sizeof(prog))) + error(1, errno, "setsockopt filter"); +} + +static int create_ring(char **ring) +{ + struct fanout_args args = { + .id = 1, + .type_flags = PACKET_FANOUT_CPU, + .max_num_members = RSS_MAX_CPUS + }; + struct sockaddr_ll ll = { 0 }; + int fd, val; + + fd = socket(PF_PACKET, SOCK_DGRAM, 0); + if (fd == -1) + error(1, errno, "socket creation failed"); + + val = TPACKET_V3; + if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, &val, sizeof(val))) + error(1, errno, "setsockopt PACKET_VERSION"); + *ring = setup_ring(fd); + + /* block packets until all rings are added to the fanout group: + * else packets can arrive during setup and get misclassified + */ + set_filter_null(fd); + + ll.sll_family = AF_PACKET; + ll.sll_ifindex = if_nametoindex(cfg_ifname); + ll.sll_protocol = cfg_family == AF_INET ? htons(ETH_P_IP) : + htons(ETH_P_IPV6); + if (bind(fd, (void *)&ll, sizeof(ll))) + error(1, errno, "bind"); + + /* must come after bind: verifies all programs in group match */ + if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &args, sizeof(args))) { + /* on failure, retry using old API if that is sufficient: + * it has a hard limit of 256 sockets, so only try if + * (a) only testing rxhash, not RSS or (b) <= 256 cpus. + * in this API, the third argument is left implicit. + */ + if (cfg_num_queues || num_cpus > 256 || + setsockopt(fd, SOL_PACKET, PACKET_FANOUT, + &args, sizeof(uint32_t))) + error(1, errno, "setsockopt PACKET_FANOUT cpu"); + } + + return fd; +} + +/* setup inet(6) socket to blackhole the test traffic, if arg '-s' */ +static int setup_sink(void) +{ + int fd, val; + + fd = socket(cfg_family, cfg_type, 0); + if (fd == -1) + error(1, errno, "socket %d.%d", cfg_family, cfg_type); + + val = 1 << 20; + if (setsockopt(fd, SOL_SOCKET, SO_RCVBUFFORCE, &val, sizeof(val))) + error(1, errno, "setsockopt rcvbuf"); + + return fd; +} + +static void setup_rings(void) +{ + int i; + + for (i = 0; i < num_cpus; i++) { + rings[i].cpu = i; + rings[i].fd = create_ring(&rings[i].mmap); + } + + /* accept packets once all rings in the fanout group are up */ + for (i = 0; i < num_cpus; i++) + set_filter(rings[i].fd); +} + +static void cleanup_rings(void) +{ + int i; + + for (i = 0; i < num_cpus; i++) { + if (munmap(rings[i].mmap, ring_block_nr * ring_block_sz)) + error(1, errno, "munmap"); + if (close(rings[i].fd)) + error(1, errno, "close"); + } +} + +static void parse_cpulist(const char *arg) +{ + do { + rx_irq_cpus[cfg_num_queues++] = strtol(arg, NULL, 10); + + arg = strchr(arg, ','); + if (!arg) + break; + arg++; // skip ',' + } while (1); +} + +static void show_cpulist(void) +{ + int i; + + for (i = 0; i < cfg_num_queues; i++) + fprintf(stderr, "rxq %d: cpu %d\n", i, rx_irq_cpus[i]); +} + +static void show_silos(void) +{ + int i; + + for (i = 0; i < cfg_num_rps_cpus; i++) + fprintf(stderr, "silo %d: cpu %d\n", i, rps_silo_to_cpu[i]); +} + +static void parse_toeplitz_key(const char *str, int slen, unsigned char *key) +{ + int i, ret, off; + + if (slen < TOEPLITZ_STR_MIN_LEN || + slen > TOEPLITZ_STR_MAX_LEN + 1) + error(1, 0, "invalid toeplitz key"); + + for (i = 0, off = 0; off < slen; i++, off += 3) { + ret = sscanf(str + off, "%hhx", &key[i]); + if (ret != 1) + error(1, 0, "key parse error at %d off %d len %d", + i, off, slen); + } +} + +static void parse_rps_bitmap(const char *arg) +{ + unsigned long bitmap; + int i; + + bitmap = strtoul(arg, NULL, 0); + + if (bitmap & ~(RPS_MAX_CPUS - 1)) + error(1, 0, "rps bitmap 0x%lx out of bounds 0..%lu", + bitmap, RPS_MAX_CPUS - 1); + + for (i = 0; i < RPS_MAX_CPUS; i++) + if (bitmap & 1UL << i) + rps_silo_to_cpu[cfg_num_rps_cpus++] = i; +} + +static void parse_opts(int argc, char **argv) +{ + static struct option long_options[] = { + {"dport", required_argument, 0, 'd'}, + {"cpus", required_argument, 0, 'C'}, + {"key", required_argument, 0, 'k'}, + {"iface", required_argument, 0, 'i'}, + {"ipv4", no_argument, 0, '4'}, + {"ipv6", no_argument, 0, '6'}, + {"sink", no_argument, 0, 's'}, + {"tcp", no_argument, 0, 't'}, + {"timeout", required_argument, 0, 'T'}, + {"udp", no_argument, 0, 'u'}, + {"verbose", no_argument, 0, 'v'}, + {"rps", required_argument, 0, 'r'}, + {0, 0, 0, 0} + }; + bool have_toeplitz = false; + int index, c; + + while ((c = getopt_long(argc, argv, "46C:d:i:k:r:stT:u:v", long_options, &index)) != -1) { + switch (c) { + case '4': + cfg_family = AF_INET; + break; + case '6': + cfg_family = AF_INET6; + break; + case 'C': + parse_cpulist(optarg); + break; + case 'd': + cfg_dport = strtol(optarg, NULL, 0); + break; + case 'i': + cfg_ifname = optarg; + break; + case 'k': + parse_toeplitz_key(optarg, strlen(optarg), + toeplitz_key); + have_toeplitz = true; + break; + case 'r': + parse_rps_bitmap(optarg); + break; + case 's': + cfg_sink = true; + break; + case 't': + cfg_type = SOCK_STREAM; + break; + case 'T': + cfg_timeout_msec = strtol(optarg, NULL, 0); + break; + case 'u': + cfg_type = SOCK_DGRAM; + break; + case 'v': + cfg_verbose = true; + break; + + default: + error(1, 0, "unknown option %c", optopt); + break; + } + } + + if (!have_toeplitz) + error(1, 0, "Must supply rss key ('-k')"); + + num_cpus = get_nprocs(); + if (num_cpus > RSS_MAX_CPUS) + error(1, 0, "increase RSS_MAX_CPUS"); + + if (cfg_num_queues && cfg_num_rps_cpus) + error(1, 0, + "Can't supply both RSS cpus ('-C') and RPS map ('-r')"); + if (cfg_verbose) { + show_cpulist(); + show_silos(); + } +} + +int main(int argc, char **argv) +{ + const int min_tests = 10; + int fd_sink = -1; + + parse_opts(argc, argv); + + if (cfg_sink) + fd_sink = setup_sink(); + + setup_rings(); + process_rings(); + cleanup_rings(); + + if (cfg_sink && close(fd_sink)) + error(1, errno, "close sink"); + + if (frames_received - frames_nohash < min_tests) + error(1, 0, "too few frames for verification"); + + return frames_error; +} -- cgit