// 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: %u)]"		" [--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;}