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Diffstat (limited to 'tools/virtio/ringtest/main.c')
| -rw-r--r-- | tools/virtio/ringtest/main.c | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/tools/virtio/ringtest/main.c b/tools/virtio/ringtest/main.c new file mode 100644 index 000000000..5a18b2301 --- /dev/null +++ b/tools/virtio/ringtest/main.c @@ -0,0 +1,391 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2016 Red Hat, Inc. + * Author: Michael S. Tsirkin <mst@redhat.com> + * + * Command line processing and common functions for ring benchmarking. + */ +#define _GNU_SOURCE +#include <getopt.h> +#include <pthread.h> +#include <assert.h> +#include <sched.h> +#include "main.h" +#include <sys/eventfd.h> +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <limits.h> + +int runcycles = 10000000; +int max_outstanding = INT_MAX; +int batch = 1; +int param = 0; + +bool do_sleep = false; +bool do_relax = false; +bool do_exit = true; + +unsigned ring_size = 256; + +static int kickfd = -1; +static int callfd = -1; + +void notify(int fd) +{ + unsigned long long v = 1; + int r; + + vmexit(); + r = write(fd, &v, sizeof v); + assert(r == sizeof v); + vmentry(); +} + +void wait_for_notify(int fd) +{ + unsigned long long v = 1; + int r; + + vmexit(); + r = read(fd, &v, sizeof v); + assert(r == sizeof v); + vmentry(); +} + +void kick(void) +{ + notify(kickfd); +} + +void wait_for_kick(void) +{ + wait_for_notify(kickfd); +} + +void call(void) +{ + notify(callfd); +} + +void wait_for_call(void) +{ + wait_for_notify(callfd); +} + +void set_affinity(const char *arg) +{ + cpu_set_t cpuset; + int ret; + pthread_t self; + long int cpu; + char *endptr; + + if (!arg) + return; + + cpu = strtol(arg, &endptr, 0); + assert(!*endptr); + + assert(cpu >= 0 && cpu < CPU_SETSIZE); + + self = pthread_self(); + CPU_ZERO(&cpuset); + CPU_SET(cpu, &cpuset); + + ret = pthread_setaffinity_np(self, sizeof(cpu_set_t), &cpuset); + assert(!ret); +} + +void poll_used(void) +{ + while (used_empty()) + busy_wait(); +} + +static void __attribute__((__flatten__)) run_guest(void) +{ + int completed_before; + int completed = 0; + int started = 0; + int bufs = runcycles; + int spurious = 0; + int r; + unsigned len; + void *buf; + int tokick = batch; + + for (;;) { + if (do_sleep) + disable_call(); + completed_before = completed; + do { + if (started < bufs && + started - completed < max_outstanding) { + r = add_inbuf(0, "Buffer\n", "Hello, world!"); + if (__builtin_expect(r == 0, true)) { + ++started; + if (!--tokick) { + tokick = batch; + if (do_sleep) + kick_available(); + } + + } + } else + r = -1; + + /* Flush out completed bufs if any */ + if (get_buf(&len, &buf)) { + ++completed; + if (__builtin_expect(completed == bufs, false)) + return; + r = 0; + } + } while (r == 0); + if (completed == completed_before) + ++spurious; + assert(completed <= bufs); + assert(started <= bufs); + if (do_sleep) { + if (used_empty() && enable_call()) + wait_for_call(); + } else { + poll_used(); + } + } +} + +void poll_avail(void) +{ + while (avail_empty()) + busy_wait(); +} + +static void __attribute__((__flatten__)) run_host(void) +{ + int completed_before; + int completed = 0; + int spurious = 0; + int bufs = runcycles; + unsigned len; + void *buf; + + for (;;) { + if (do_sleep) { + if (avail_empty() && enable_kick()) + wait_for_kick(); + } else { + poll_avail(); + } + if (do_sleep) + disable_kick(); + completed_before = completed; + while (__builtin_expect(use_buf(&len, &buf), true)) { + if (do_sleep) + call_used(); + ++completed; + if (__builtin_expect(completed == bufs, false)) + return; + } + if (completed == completed_before) + ++spurious; + assert(completed <= bufs); + if (completed == bufs) + break; + } +} + +void *start_guest(void *arg) +{ + set_affinity(arg); + run_guest(); + pthread_exit(NULL); +} + +void *start_host(void *arg) +{ + set_affinity(arg); + run_host(); + pthread_exit(NULL); +} + +static const char optstring[] = ""; +static const struct option longopts[] = { + { + .name = "help", + .has_arg = no_argument, + .val = 'h', + }, + { + .name = "host-affinity", + .has_arg = required_argument, + .val = 'H', + }, + { + .name = "guest-affinity", + .has_arg = required_argument, + .val = 'G', + }, + { + .name = "ring-size", + .has_arg = required_argument, + .val = 'R', + }, + { + .name = "run-cycles", + .has_arg = required_argument, + .val = 'C', + }, + { + .name = "outstanding", + .has_arg = required_argument, + .val = 'o', + }, + { + .name = "batch", + .has_arg = required_argument, + .val = 'b', + }, + { + .name = "param", + .has_arg = required_argument, + .val = 'p', + }, + { + .name = "sleep", + .has_arg = no_argument, + .val = 's', + }, + { + .name = "relax", + .has_arg = no_argument, + .val = 'x', + }, + { + .name = "exit", + .has_arg = no_argument, + .val = 'e', + }, + { + } +}; + +static void help(void) +{ + fprintf(stderr, "Usage: <test> [--help]" + " [--host-affinity H]" + " [--guest-affinity G]" + " [--ring-size R (default: %d)]" + " [--run-cycles C (default: %d)]" + " [--batch b]" + " [--outstanding o]" + " [--param p]" + " [--sleep]" + " [--relax]" + " [--exit]" + "\n", + ring_size, + runcycles); +} + +int main(int argc, char **argv) +{ + int ret; + pthread_t host, guest; + void *tret; + char *host_arg = NULL; + char *guest_arg = NULL; + char *endptr; + long int c; + + kickfd = eventfd(0, 0); + assert(kickfd >= 0); + callfd = eventfd(0, 0); + assert(callfd >= 0); + + for (;;) { + int o = getopt_long(argc, argv, optstring, longopts, NULL); + switch (o) { + case -1: + goto done; + case '?': + help(); + exit(2); + case 'H': + host_arg = optarg; + break; + case 'G': + guest_arg = optarg; + break; + case 'R': + ring_size = strtol(optarg, &endptr, 0); + assert(ring_size && !(ring_size & (ring_size - 1))); + assert(!*endptr); + break; + case 'C': + c = strtol(optarg, &endptr, 0); + assert(!*endptr); + assert(c > 0 && c < INT_MAX); + runcycles = c; + break; + case 'o': + c = strtol(optarg, &endptr, 0); + assert(!*endptr); + assert(c > 0 && c < INT_MAX); + max_outstanding = c; + break; + case 'p': + c = strtol(optarg, &endptr, 0); + assert(!*endptr); + assert(c > 0 && c < INT_MAX); + param = c; + break; + case 'b': + c = strtol(optarg, &endptr, 0); + assert(!*endptr); + assert(c > 0 && c < INT_MAX); + batch = c; + break; + case 's': + do_sleep = true; + break; + case 'x': + do_relax = true; + break; + case 'e': + do_exit = true; + break; + default: + help(); + exit(4); + break; + } + } + + /* does nothing here, used to make sure all smp APIs compile */ + smp_acquire(); + smp_release(); + smp_mb(); +done: + + if (batch > max_outstanding) + batch = max_outstanding; + + if (optind < argc) { + help(); + exit(4); + } + alloc_ring(); + + ret = pthread_create(&host, NULL, start_host, host_arg); + assert(!ret); + ret = pthread_create(&guest, NULL, start_guest, guest_arg); + assert(!ret); + + ret = pthread_join(guest, &tret); + assert(!ret); + ret = pthread_join(host, &tret); + assert(!ret); + return 0; +} |