diff options
Diffstat (limited to 'tools/testing/selftests/net/tcp_mmap.c')
-rw-r--r-- | tools/testing/selftests/net/tcp_mmap.c | 517 |
1 files changed, 517 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/tcp_mmap.c b/tools/testing/selftests/net/tcp_mmap.c new file mode 100644 index 000000000..00f837c9b --- /dev/null +++ b/tools/testing/selftests/net/tcp_mmap.c @@ -0,0 +1,517 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2018 Google Inc. + * Author: Eric Dumazet (edumazet@google.com) + * + * Reference program demonstrating tcp mmap() usage, + * and SO_RCVLOWAT hints for receiver. + * + * Note : NIC with header split is needed to use mmap() on TCP : + * Each incoming frame must be a multiple of PAGE_SIZE bytes of TCP payload. + * + * How to use on loopback interface : + * + * ifconfig lo mtu 61512 # 15*4096 + 40 (ipv6 header) + 32 (TCP with TS option header) + * tcp_mmap -s -z & + * tcp_mmap -H ::1 -z + * + * Or leave default lo mtu, but use -M option to set TCP_MAXSEG option to (4096 + 12) + * (4096 : page size on x86, 12: TCP TS option length) + * tcp_mmap -s -z -M $((4096+12)) & + * tcp_mmap -H ::1 -z -M $((4096+12)) + * + * Note: -z option on sender uses MSG_ZEROCOPY, which forces a copy when packets go through loopback interface. + * We might use sendfile() instead, but really this test program is about mmap(), for receivers ;) + * + * $ ./tcp_mmap -s & # Without mmap() + * $ for i in {1..4}; do ./tcp_mmap -H ::1 -z ; done + * received 32768 MB (0 % mmap'ed) in 14.1157 s, 19.4732 Gbit + * cpu usage user:0.057 sys:7.815, 240.234 usec per MB, 65531 c-switches + * received 32768 MB (0 % mmap'ed) in 14.6833 s, 18.7204 Gbit + * cpu usage user:0.043 sys:8.103, 248.596 usec per MB, 65524 c-switches + * received 32768 MB (0 % mmap'ed) in 11.143 s, 24.6682 Gbit + * cpu usage user:0.044 sys:6.576, 202.026 usec per MB, 65519 c-switches + * received 32768 MB (0 % mmap'ed) in 14.9056 s, 18.4413 Gbit + * cpu usage user:0.036 sys:8.193, 251.129 usec per MB, 65530 c-switches + * $ kill %1 # kill tcp_mmap server + * + * $ ./tcp_mmap -s -z & # With mmap() + * $ for i in {1..4}; do ./tcp_mmap -H ::1 -z ; done + * received 32768 MB (99.9939 % mmap'ed) in 6.73792 s, 40.7956 Gbit + * cpu usage user:0.045 sys:2.827, 87.6465 usec per MB, 65532 c-switches + * received 32768 MB (99.9939 % mmap'ed) in 7.26732 s, 37.8238 Gbit + * cpu usage user:0.037 sys:3.087, 95.3369 usec per MB, 65532 c-switches + * received 32768 MB (99.9939 % mmap'ed) in 7.61661 s, 36.0893 Gbit + * cpu usage user:0.046 sys:3.559, 110.016 usec per MB, 65529 c-switches + * received 32768 MB (99.9939 % mmap'ed) in 7.43764 s, 36.9577 Gbit + * cpu usage user:0.035 sys:3.467, 106.873 usec per MB, 65530 c-switches + */ +#define _GNU_SOURCE +#include <pthread.h> +#include <sys/types.h> +#include <fcntl.h> +#include <error.h> +#include <sys/socket.h> +#include <sys/mman.h> +#include <sys/resource.h> +#include <unistd.h> +#include <string.h> +#include <stdlib.h> +#include <stdio.h> +#include <errno.h> +#include <time.h> +#include <sys/time.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <poll.h> +#include <linux/tcp.h> +#include <assert.h> + +#ifndef MSG_ZEROCOPY +#define MSG_ZEROCOPY 0x4000000 +#endif + +#define FILE_SZ (1ULL << 35) +static int cfg_family = AF_INET6; +static socklen_t cfg_alen = sizeof(struct sockaddr_in6); +static int cfg_port = 8787; + +static int rcvbuf; /* Default: autotuning. Can be set with -r <integer> option */ +static int sndbuf; /* Default: autotuning. Can be set with -w <integer> option */ +static int zflg; /* zero copy option. (MSG_ZEROCOPY for sender, mmap() for receiver */ +static int xflg; /* hash received data (simple xor) (-h option) */ +static int keepflag; /* -k option: receiver shall keep all received file in memory (no munmap() calls) */ + +static size_t chunk_size = 512*1024; + +static size_t map_align; + +unsigned long htotal; + +static inline void prefetch(const void *x) +{ +#if defined(__x86_64__) + asm volatile("prefetcht0 %P0" : : "m" (*(const char *)x)); +#endif +} + +void hash_zone(void *zone, unsigned int length) +{ + unsigned long temp = htotal; + + while (length >= 8*sizeof(long)) { + prefetch(zone + 384); + temp ^= *(unsigned long *)zone; + temp ^= *(unsigned long *)(zone + sizeof(long)); + temp ^= *(unsigned long *)(zone + 2*sizeof(long)); + temp ^= *(unsigned long *)(zone + 3*sizeof(long)); + temp ^= *(unsigned long *)(zone + 4*sizeof(long)); + temp ^= *(unsigned long *)(zone + 5*sizeof(long)); + temp ^= *(unsigned long *)(zone + 6*sizeof(long)); + temp ^= *(unsigned long *)(zone + 7*sizeof(long)); + zone += 8*sizeof(long); + length -= 8*sizeof(long); + } + while (length >= 1) { + temp ^= *(unsigned char *)zone; + zone += 1; + length--; + } + htotal = temp; +} + +#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1)) +#define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to)) + + +static void *mmap_large_buffer(size_t need, size_t *allocated) +{ + void *buffer; + size_t sz; + + /* Attempt to use huge pages if possible. */ + sz = ALIGN_UP(need, map_align); + buffer = mmap(NULL, sz, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0); + + if (buffer == (void *)-1) { + sz = need; + buffer = mmap(NULL, sz, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (buffer != (void *)-1) + fprintf(stderr, "MAP_HUGETLB attempt failed, look at /sys/kernel/mm/hugepages for optimal performance\n"); + } + *allocated = sz; + return buffer; +} + +void *child_thread(void *arg) +{ + unsigned long total_mmap = 0, total = 0; + struct tcp_zerocopy_receive zc; + unsigned long delta_usec; + int flags = MAP_SHARED; + struct timeval t0, t1; + char *buffer = NULL; + void *raddr = NULL; + void *addr = NULL; + double throughput; + struct rusage ru; + size_t buffer_sz; + int lu, fd; + + fd = (int)(unsigned long)arg; + + gettimeofday(&t0, NULL); + + fcntl(fd, F_SETFL, O_NDELAY); + buffer = mmap_large_buffer(chunk_size, &buffer_sz); + if (buffer == (void *)-1) { + perror("mmap"); + goto error; + } + if (zflg) { + raddr = mmap(NULL, chunk_size + map_align, PROT_READ, flags, fd, 0); + if (raddr == (void *)-1) { + perror("mmap"); + zflg = 0; + } else { + addr = ALIGN_PTR_UP(raddr, map_align); + } + } + while (1) { + struct pollfd pfd = { .fd = fd, .events = POLLIN, }; + int sub; + + poll(&pfd, 1, 10000); + if (zflg) { + socklen_t zc_len = sizeof(zc); + int res; + + memset(&zc, 0, sizeof(zc)); + zc.address = (__u64)((unsigned long)addr); + zc.length = chunk_size; + + res = getsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, + &zc, &zc_len); + if (res == -1) + break; + + if (zc.length) { + assert(zc.length <= chunk_size); + total_mmap += zc.length; + if (xflg) + hash_zone(addr, zc.length); + /* It is more efficient to unmap the pages right now, + * instead of doing this in next TCP_ZEROCOPY_RECEIVE. + */ + madvise(addr, zc.length, MADV_DONTNEED); + total += zc.length; + } + if (zc.recv_skip_hint) { + assert(zc.recv_skip_hint <= chunk_size); + lu = read(fd, buffer, zc.recv_skip_hint); + if (lu > 0) { + if (xflg) + hash_zone(buffer, lu); + total += lu; + } + } + continue; + } + sub = 0; + while (sub < chunk_size) { + lu = read(fd, buffer + sub, chunk_size - sub); + if (lu == 0) + goto end; + if (lu < 0) + break; + if (xflg) + hash_zone(buffer + sub, lu); + total += lu; + sub += lu; + } + } +end: + gettimeofday(&t1, NULL); + delta_usec = (t1.tv_sec - t0.tv_sec) * 1000000 + t1.tv_usec - t0.tv_usec; + + throughput = 0; + if (delta_usec) + throughput = total * 8.0 / (double)delta_usec / 1000.0; + getrusage(RUSAGE_THREAD, &ru); + if (total > 1024*1024) { + unsigned long total_usec; + unsigned long mb = total >> 20; + total_usec = 1000000*ru.ru_utime.tv_sec + ru.ru_utime.tv_usec + + 1000000*ru.ru_stime.tv_sec + ru.ru_stime.tv_usec; + printf("received %lg MB (%lg %% mmap'ed) in %lg s, %lg Gbit\n" + " cpu usage user:%lg sys:%lg, %lg usec per MB, %lu c-switches\n", + total / (1024.0 * 1024.0), + 100.0*total_mmap/total, + (double)delta_usec / 1000000.0, + throughput, + (double)ru.ru_utime.tv_sec + (double)ru.ru_utime.tv_usec / 1000000.0, + (double)ru.ru_stime.tv_sec + (double)ru.ru_stime.tv_usec / 1000000.0, + (double)total_usec/mb, + ru.ru_nvcsw); + } +error: + munmap(buffer, buffer_sz); + close(fd); + if (zflg) + munmap(raddr, chunk_size + map_align); + pthread_exit(0); +} + +static void apply_rcvsnd_buf(int fd) +{ + if (rcvbuf && setsockopt(fd, SOL_SOCKET, + SO_RCVBUF, &rcvbuf, sizeof(rcvbuf)) == -1) { + perror("setsockopt SO_RCVBUF"); + } + + if (sndbuf && setsockopt(fd, SOL_SOCKET, + SO_SNDBUF, &sndbuf, sizeof(sndbuf)) == -1) { + perror("setsockopt SO_SNDBUF"); + } +} + + +static void setup_sockaddr(int domain, const char *str_addr, + struct sockaddr_storage *sockaddr) +{ + struct sockaddr_in6 *addr6 = (void *) sockaddr; + struct sockaddr_in *addr4 = (void *) sockaddr; + + switch (domain) { + case PF_INET: + memset(addr4, 0, sizeof(*addr4)); + addr4->sin_family = AF_INET; + addr4->sin_port = htons(cfg_port); + if (str_addr && + inet_pton(AF_INET, str_addr, &(addr4->sin_addr)) != 1) + error(1, 0, "ipv4 parse error: %s", str_addr); + break; + case PF_INET6: + memset(addr6, 0, sizeof(*addr6)); + addr6->sin6_family = AF_INET6; + addr6->sin6_port = htons(cfg_port); + if (str_addr && + inet_pton(AF_INET6, str_addr, &(addr6->sin6_addr)) != 1) + error(1, 0, "ipv6 parse error: %s", str_addr); + break; + default: + error(1, 0, "illegal domain"); + } +} + +static void do_accept(int fdlisten) +{ + pthread_attr_t attr; + int rcvlowat; + + pthread_attr_init(&attr); + pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); + + rcvlowat = chunk_size; + if (setsockopt(fdlisten, SOL_SOCKET, SO_RCVLOWAT, + &rcvlowat, sizeof(rcvlowat)) == -1) { + perror("setsockopt SO_RCVLOWAT"); + } + + apply_rcvsnd_buf(fdlisten); + + while (1) { + struct sockaddr_in addr; + socklen_t addrlen = sizeof(addr); + pthread_t th; + int fd, res; + + fd = accept(fdlisten, (struct sockaddr *)&addr, &addrlen); + if (fd == -1) { + perror("accept"); + continue; + } + res = pthread_create(&th, &attr, child_thread, + (void *)(unsigned long)fd); + if (res) { + errno = res; + perror("pthread_create"); + close(fd); + } + } +} + +/* Each thread should reserve a big enough vma to avoid + * spinlock collisions in ptl locks. + * This size is 2MB on x86_64, and is exported in /proc/meminfo. + */ +static unsigned long default_huge_page_size(void) +{ + FILE *f = fopen("/proc/meminfo", "r"); + unsigned long hps = 0; + size_t linelen = 0; + char *line = NULL; + + if (!f) + return 0; + while (getline(&line, &linelen, f) > 0) { + if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) { + hps <<= 10; + break; + } + } + free(line); + fclose(f); + return hps; +} + +int main(int argc, char *argv[]) +{ + struct sockaddr_storage listenaddr, addr; + unsigned int max_pacing_rate = 0; + uint64_t total = 0; + char *host = NULL; + int fd, c, on = 1; + size_t buffer_sz; + char *buffer; + int sflg = 0; + int mss = 0; + + while ((c = getopt(argc, argv, "46p:svr:w:H:zxkP:M:C:a:")) != -1) { + switch (c) { + case '4': + cfg_family = PF_INET; + cfg_alen = sizeof(struct sockaddr_in); + break; + case '6': + cfg_family = PF_INET6; + cfg_alen = sizeof(struct sockaddr_in6); + break; + case 'p': + cfg_port = atoi(optarg); + break; + case 'H': + host = optarg; + break; + case 's': /* server : listen for incoming connections */ + sflg++; + break; + case 'r': + rcvbuf = atoi(optarg); + break; + case 'w': + sndbuf = atoi(optarg); + break; + case 'z': + zflg = 1; + break; + case 'M': + mss = atoi(optarg); + break; + case 'x': + xflg = 1; + break; + case 'k': + keepflag = 1; + break; + case 'P': + max_pacing_rate = atoi(optarg) ; + break; + case 'C': + chunk_size = atol(optarg); + break; + case 'a': + map_align = atol(optarg); + break; + default: + exit(1); + } + } + if (!map_align) { + map_align = default_huge_page_size(); + /* if really /proc/meminfo is not helping, + * we use the default x86_64 hugepagesize. + */ + if (!map_align) + map_align = 2*1024*1024; + } + if (sflg) { + int fdlisten = socket(cfg_family, SOCK_STREAM, 0); + + if (fdlisten == -1) { + perror("socket"); + exit(1); + } + apply_rcvsnd_buf(fdlisten); + setsockopt(fdlisten, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); + + setup_sockaddr(cfg_family, host, &listenaddr); + + if (mss && + setsockopt(fdlisten, IPPROTO_TCP, TCP_MAXSEG, + &mss, sizeof(mss)) == -1) { + perror("setsockopt TCP_MAXSEG"); + exit(1); + } + if (bind(fdlisten, (const struct sockaddr *)&listenaddr, cfg_alen) == -1) { + perror("bind"); + exit(1); + } + if (listen(fdlisten, 128) == -1) { + perror("listen"); + exit(1); + } + do_accept(fdlisten); + } + + buffer = mmap_large_buffer(chunk_size, &buffer_sz); + if (buffer == (char *)-1) { + perror("mmap"); + exit(1); + } + + fd = socket(cfg_family, SOCK_STREAM, 0); + if (fd == -1) { + perror("socket"); + exit(1); + } + apply_rcvsnd_buf(fd); + + setup_sockaddr(cfg_family, host, &addr); + + if (mss && + setsockopt(fd, IPPROTO_TCP, TCP_MAXSEG, &mss, sizeof(mss)) == -1) { + perror("setsockopt TCP_MAXSEG"); + exit(1); + } + if (connect(fd, (const struct sockaddr *)&addr, cfg_alen) == -1) { + perror("connect"); + exit(1); + } + if (max_pacing_rate && + setsockopt(fd, SOL_SOCKET, SO_MAX_PACING_RATE, + &max_pacing_rate, sizeof(max_pacing_rate)) == -1) + perror("setsockopt SO_MAX_PACING_RATE"); + + if (zflg && setsockopt(fd, SOL_SOCKET, SO_ZEROCOPY, + &on, sizeof(on)) == -1) { + perror("setsockopt SO_ZEROCOPY, (-z option disabled)"); + zflg = 0; + } + while (total < FILE_SZ) { + int64_t wr = FILE_SZ - total; + + if (wr > chunk_size) + wr = chunk_size; + /* Note : we just want to fill the pipe with 0 bytes */ + wr = send(fd, buffer, (size_t)wr, zflg ? MSG_ZEROCOPY : 0); + if (wr <= 0) + break; + total += wr; + } + close(fd); + munmap(buffer, buffer_sz); + return 0; +} |