masim.c

#include <argp.h>
#include <err.h>
#include <fcntl.h>
#include <locale.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <time.h>
#include <unistd.h>

#include "misc.h"
#include "masim.h"

#define HUGETLB_PROTECTION (PROT_READ | PROT_WRITE)

#ifdef __ia64__
#define HUGETLB_ADDR (void *)(0x8000000000000000UL)
#define HUGETLB_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
#else
#define HUGETLB_ADDR (void *)(0x0UL)
#define HUGETLB_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
#endif
int use_hugetlb = 0;

#define LEN_ARRAY(x) (sizeof(x) / sizeof(*x))

enum hintmethod {
	NONE,
	MADVISE,
	MLOCK,
};

enum hintmethod hintmethod = NONE;
int quiet;
enum rw_mode default_rw_mode = WRITE_ONLY;
int nr_repeats = 1;

void pr_regions(struct mregion *regions, size_t nr_regions)
{
	struct mregion *region;
	int i;

	printf("memory regions\n");
	for (i = 0; i < nr_regions; i++) {
		region = &regions[i];
		printf("\t%s: %zu bytes\n", region->name, region->sz);
	}
	printf("\n");
}

void pr_phase(struct phase *phase)
{
	struct access *pattern;
	int j;

	printf("Phase (%s) for %u ms\n", phase->name, phase->time_ms);
	for (j = 0; j < phase->nr_patterns; j++) {
		pattern = &phase->patterns[j];
		printf("\tPattern %d\n", j);
		printf("\t\t%s access region %s with stride %zu\n",
				pattern->random_access ?
				"randomly" : "sequentially",
				pattern->mregion == NULL ?
				"..." : pattern->mregion->name,
				pattern->stride);
	}

}

void pr_phases(struct phase *phases, int nr_phases)
{
	int i;

	for (i = 0; i < nr_phases; i++)
		pr_phase(&phases[i]);
}

struct access_config {
	struct mregion *regions;
	ssize_t nr_regions;
	struct phase *phases;
	ssize_t nr_phases;
};

#define RAND_BATCH	1000
#define RAND_ARR_SZ	1000
size_t rndints[RAND_BATCH][RAND_ARR_SZ];

inline static size_t rand64() {
	return ((size_t)rand() << 32) | rand();
}

static void init_rndints(void)
{
	int i, j;

	for (i = 0; i < RAND_BATCH; i++)
		for (j = 0; j < RAND_ARR_SZ; j++)
			rndints[i][j] = rand64();
	rndints[0][0] = 1;
}

/*
 * Returns a random integer
 */
static size_t rndint(void)
{
	static int rndofs;
	static int rndarr;

	if (rndofs == RAND_ARR_SZ) {
		rndarr = rand() % RAND_BATCH;
		rndofs = 0;
	}

	return rndints[rndarr][rndofs++];
}

static void do_rnd_ro(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	int i;
	char __attribute__((unused)) read_val;

	for (i = 0; i < batch; i++)
		read_val = ACCESS_ONCE(rr[rndint() % region->sz]);
}

static void do_seq_ro(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	size_t offset = access->last_offset;
	int i;
	char __attribute__((unused)) read_val;

	for (i = 0; i < batch; i++) {
		offset += access->stride;
		if (offset >= region->sz)
			offset = 0;
		read_val = ACCESS_ONCE(rr[offset]);
	}
	access->last_offset = offset;
}

static void do_rnd_wo(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	int i;

	for (i = 0; i < batch; i++)
		ACCESS_ONCE(rr[rndint() % region->sz]) = 1;
}

static void do_seq_wo(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	size_t offset = access->last_offset;
	int i;

	for (i = 0; i < batch; i++) {
		offset += access->stride;
		if (offset >= region->sz)
			offset = 0;
		ACCESS_ONCE(rr[offset]) = 1;
	}
	access->last_offset = offset;
}

static void do_rnd_rw(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	int i;
	char read_val;

	for (i = 0; i < batch; i++) {
		size_t rndoffset;

		rndoffset = rndint() % region->sz;
		read_val = ACCESS_ONCE(rr[rndoffset]);
		ACCESS_ONCE(rr[rndoffset]) = read_val + 1;
	}
}

static void do_seq_rw(struct access *access, int batch)
{
	struct mregion *region = access->mregion;
	char *rr = region->region;
	size_t offset = access->last_offset;
	int i;
	char read_val;

	for (i = 0; i < batch; i++) {
		offset += access->stride;
		if (offset >= region->sz)
			offset = 0;
		read_val = ACCESS_ONCE(rr[offset]);
		ACCESS_ONCE(rr[offset]) = read_val + 1;
	}
	access->last_offset = offset;
}

static unsigned long long do_access(struct access *access)
{
	static const int batch = 1024 * 128;

	switch (access->rw_mode) {
	case READ_ONLY:
		if (access->random_access)
			do_rnd_ro(access, batch);
		else
			do_seq_ro(access, batch);
		break;
	case WRITE_ONLY:
		if (access->random_access)
			do_rnd_wo(access, batch);
		else
			do_seq_wo(access, batch);
		break;
	case READ_WRITE:
		if (access->random_access)
			do_rnd_rw(access, batch);
		else
			do_seq_rw(access, batch);
		break;
	default:
		break;
	}

	return batch;
}

#define SZ_PAGE	4096
void hint_access_pattern(struct phase *phase)
{
	static const unsigned MEMSZ_OFFSET = 10 * 1024 * 1024;	/* 10 MB */
	static const unsigned FREQ_OFFSET = 70;	/* 70 % */

	struct access *acc;
	struct mregion *region;
	int freq_offset;
	int i;

	if (hintmethod == MLOCK)
		munlockall();

	freq_offset = phase->total_probability * FREQ_OFFSET / 100;

	for (i = 0; i < phase->nr_patterns; i++) {
		acc = &phase->patterns[i];
		region = acc->mregion;

		if (region->sz < MEMSZ_OFFSET)
			continue;

		if (acc->probability < freq_offset)
			continue;

		if (hintmethod == MLOCK) {
			if (mlock(region->region, region->sz) == -1)
				err(-1, "failed mlock");
		} else if (hintmethod == MADVISE) {
			/* madvise receive page size aligned region only */
			uintptr_t aligned;

			aligned = (uintptr_t)region->region;
			if (aligned % SZ_PAGE != 0)
				aligned = aligned + SZ_PAGE -
					(aligned % SZ_PAGE);

			if (madvise((void *)aligned, region->sz,
						MADV_WILLNEED) == -1)
				err(-1, "failed madvise");
		}
	}
}

void exec_phase(struct phase *phase)
{
	struct access *pattern;
	unsigned long long nr_access;
	unsigned long long start;
	int randn;
	size_t i;
	static unsigned long long cpu_cycle_ms;

	if (!cpu_cycle_ms)
		cpu_cycle_ms = aclk_freq() / 1000;

	start = aclk_clock();
	nr_access = 0;

	if (hintmethod != NONE)
		hint_access_pattern(phase);

	while (1) {
		if (phase->total_probability)
			randn = rndint() % phase->total_probability;
		else
			randn = -1;
		for (i = 0; i < phase->nr_patterns; i++) {
			int prob_start, prob_end;

			pattern = &phase->patterns[i];
			prob_start = pattern->prob_start;
			prob_end = prob_start + pattern->probability;
			if (randn >= prob_start && randn < prob_end)
				nr_access += do_access(pattern);
		}

		if (aclk_clock() - start > cpu_cycle_ms * phase->time_ms)
			break;
	}
	if (!quiet)
		printf("%s:\t%'20llu accesses/msec, %llu msecs run\n",
				phase->name,
				nr_access /
				((aclk_clock() - start) / cpu_cycle_ms),
				((aclk_clock() - start) / cpu_cycle_ms));
}

void exec_config(struct access_config *config)
{
	struct mregion *region;
	size_t i;

	for (i = 0; i < config->nr_regions; i++) {
		region = &config->regions[i];
		if (use_hugetlb) {
			region->region = mmap(HUGETLB_ADDR, region->sz,
					HUGETLB_PROTECTION, HUGETLB_FLAGS, -1,
					0);
			if (region->region == MAP_FAILED) {
				perror("mmap");
				exit(1);
			}
		} else {
			region->region = (char *)malloc(region->sz);
		}
	}

	for (i = 0; i < config->nr_phases; i++)
		exec_phase(&config->phases[i]);

	for (i = 0; i < config->nr_regions; i++) {
		region = &config->regions[i];
		if (use_hugetlb)
			munmap(HUGETLB_ADDR, region->sz);
		else
			free(region->region);
	}
}

size_t len_line(char *str, size_t lim_seek)
{
	size_t i;

	for (i = 0; i < lim_seek; i++) {
		if (str[i] == '\n')
			break;
	}

	if (i == lim_seek)
		return -1;

	return i;
}

/* Read exactly required bytes from a file */
void readall(int file, char *buf, ssize_t sz)
{
	ssize_t sz_read;
	ssize_t sz_total_read = 0;
	while (1) {
		sz_read = read(file, buf + sz_total_read, sz - sz_total_read);
		if (sz_read == -1)
			err(1, "read() failed!");
		sz_total_read += sz_read;
		if (sz_total_read == sz)
			return;
	}
}

char *rm_comments(char *orig, ssize_t origsz)
{
	char *read_cursor;
	char *write_cursor;
	size_t len;
	size_t offset;
	char *result;

	result = (char *)malloc(origsz);
	read_cursor = orig;
	write_cursor = result;
	offset = 0;
	while (1) {
		read_cursor = orig + offset;
		len = len_line(read_cursor, origsz - offset);
		if (len == -1)
			break;
		if (read_cursor[0] == '#')
			goto nextline;
		strncpy(write_cursor, read_cursor, len + 1);
		write_cursor += len + 1;
nextline:
		offset += len + 1;
	}
	*write_cursor = '\0';

	return result;
}

ssize_t paragraph_len(char *str, ssize_t len)
{
	ssize_t i;

	for (i = 0; i < len - 1; i++) {
		if (str[i] == '\n' && str[i + 1] == '\n')
			return i;
	}
	return -1;
}

size_t parse_regions(char *str, struct mregion **regions_ptr)
{
	int i;
	struct mregion *regions;
	struct mregion *r;
	size_t nr_regions;
	char **lines;
	char **fields;
	int nr_fields;

	nr_regions = astr_split(str, '\n', &lines);
	if (nr_regions < 1)
		err(1, "Not enough lines");
	regions = (struct mregion *)malloc(sizeof(struct mregion) * nr_regions);

	for (i = 0; i < nr_regions; i++) {
		r = &regions[i];
		nr_fields = astr_split(lines[i], ',', &fields);
		if (nr_fields != 2)
			err(1, "Wrong format config file: %s", lines[i]);
		strcpy(r->name, fields[0]);
		r->sz = atoll(fields[1]);
		astr_free_str_array(fields, nr_fields);
	}

	astr_free_str_array(lines, nr_regions);
	*regions_ptr = regions;

	return nr_regions;
}

enum rw_mode parse_rwmode(char *input)
{
	char *rwmode = malloc(strlen(input) + 1);

	sscanf(input, "%s", rwmode);

	if (!strncmp(rwmode, "ro", 2)) {
		return READ_ONLY;
	} else if (!strncmp(rwmode, "wo", 2)) {
		return WRITE_ONLY;
	} else if (!strncmp(rwmode, "rw", 2)) {
		return READ_WRITE;
	} else {
		fprintf(stderr, "wrong rw mode: %s\n", rwmode);
		exit(1);
	}
}

/**
 * parse_phase - Parse a phase from string lines
 *
 * Return number of lines for this phase
 */
int parse_phase(char *lines[], int nr_lines, struct phase *p,
		size_t nr_regions, struct mregion *regions)
{
	struct access *patterns;
	char **fields;
	int nr_fields;
	struct access *a;
	int j, k;

	if (nr_lines < 3)
		errx(1, "%s: Wrong number of lines! %d\n", __func__, nr_lines);

	p->name = (char *)malloc((strlen(lines[0]) + 1) * sizeof(char));
	strcpy(p->name, lines[0]);
	p->time_ms = atoi(lines[1]);
	p->nr_patterns = nr_lines - 2;
	p->total_probability = 0;
	lines += 2;
	patterns = (struct access *)malloc(p->nr_patterns *
			sizeof(struct access));
	p->patterns = patterns;
	for (j = 0; j < p->nr_patterns; j++) {
		nr_fields = astr_split(lines[0], ',', &fields);
		if (nr_fields != 4 && nr_fields != 5)
			err(1, "Wrong number of fields! %s\n",
					lines[0]);
		a = &patterns[j];
		a->mregion = NULL;
		for (k = 0; k < nr_regions; k++) {
			if (strcmp(fields[0], regions[k].name) == 0) {
				a->mregion = &regions[k];
				break;
			}
		}
		if (a->mregion == NULL)
			err(1, "Cannot find region with name %s",
					fields[0]);
		a->random_access = atoi(fields[1]);
		a->stride = atoi(fields[2]);
		a->probability = atoi(fields[3]);
		if (nr_fields == 5) {
			a->rw_mode = parse_rwmode(fields[4]);
		} else {
			a->rw_mode = default_rw_mode;
		}
		a->prob_start = p->total_probability;
		a->last_offset = 0;
		lines++;
		astr_free_str_array(fields, nr_fields);
		p->total_probability += a->probability;
	}
	return 2 + p->nr_patterns;
}

size_t parse_phases(char *str, struct phase **phases_ptr,
		size_t nr_regions, struct mregion *regions)
{
	struct phase *phases;
	struct phase *p;
	size_t nr_phases;
	char **lines_orig;
	char **lines;
	int nr_lines;
	int nr_lines_paragraph;
	int i, j;

	nr_phases = 0;
	nr_lines = astr_split(str, '\n', &lines_orig);
	lines = lines_orig;
	if (nr_lines < 4)	/* phase name, time, nr patterns, pattern */
		err(1, "Not enough lines for phases %s", str);

	for (i = 0; i < nr_lines; i++) {
		if (lines_orig[i][0] == '\0')
			nr_phases++;
	}

	phases = (struct phase *)malloc(nr_phases * sizeof(struct phase));

	for (i = 0; i < nr_phases; i++) {
		nr_lines_paragraph = 0;
		for (j = 0; j < nr_lines; j++) {
			if (lines[j][0] == '\0')
				break;
			nr_lines_paragraph++;
		}

		p = &phases[i];
		lines += parse_phase(&lines[0], nr_lines_paragraph,
				p, nr_regions, regions) + 1;
	}
	astr_free_str_array(lines_orig, nr_lines);

	*phases_ptr = phases;
	return nr_phases;
}

void read_config(char *cfgpath, struct access_config *config_ptr)
{
	struct stat sb;
	char *cfgstr;
	int f;
	char *content;
	int len_paragraph;
	size_t nr_regions;
	struct mregion *mregions;

	size_t nr_phases;
	struct phase *phases;

	f = open(cfgpath, O_RDONLY);
	if (f == -1)
		err(1, "open(\"%s\") failed", cfgpath);
	if (fstat(f, &sb))
		err(1, "fstat() for config file (%s) failed", cfgpath);
	cfgstr = (char *)malloc(sb.st_size * sizeof(char));
	readall(f, cfgstr, sb.st_size);
	close(f);

	content = rm_comments(cfgstr, sb.st_size);
	free(cfgstr);

	len_paragraph = paragraph_len(content, strlen(content));
	if (len_paragraph == -1)
		err(1, "Wrong file format");
	content[len_paragraph] = '\0';
	nr_regions = parse_regions(content, &mregions);

	content += len_paragraph + 2;	/* plus 2 for '\n\n' */
	nr_phases = parse_phases(content, &phases, nr_regions, mregions);

	config_ptr->regions = mregions;
	config_ptr->nr_regions = nr_regions;
	config_ptr->phases = phases;
	config_ptr->nr_phases = nr_phases;
}

static struct argp_option options[] = {
	{
		.name = "pr_config",
		.key = 'p',
		.arg = 0,
		.flags = 0,
		.doc = "flag for configuration content print",
		.group = 0,
	},
	{
		.name = "dry_run",
		.key = 'd',
		.arg = 0,
		.flags = 0,
		.doc = "flag for dry run; If this flag is set, "
			"the program ends without real access",
		.group = 0,
	},
	{
		.name = "quiet",
		.key = 'q',
		.arg = 0,
		.flags = 0,
		.doc = "suppress all normal output",
		.group = 0,
	},
	{
		.name = "silent",
		.key = 'q',
		.arg = 0,
		.flags = OPTION_ALIAS,
		.doc = "suppress all normal output",
		.group = 0,
	},
	{
		.name = "hint",
		.key = 't',
		.arg = "<hint method>",
		.flags = 0,
		.doc = "gives access pattern hint to system with given method",
		.group = 0,
	},
	{
		.name = "default_rw_mode",
		.key = 'r',
		.arg = "<ro|wo|rw>",
		.flags = 0,
		.doc = "set default read/write mode as this",
		.group = 0,
	},
	{
		.name = "use_hugetlb",
		.key = 'h',
		.arg = 0,
		.flags = 0,
		.doc = "use hugepages",
		.group = 0,
	},
	{
		.name = "repeat",
		.key = 'c',
		.arg = "<count>",
		.flags = 0,
		.doc = "repeat the run <count> times",
		.group = 0,
	},
	{}
};

char *config_file = "configs/default";
int do_print_config;
int dryrun;

error_t parse_option(int key, char *arg, struct argp_state *state)
{
	switch(key) {
	case ARGP_KEY_ARG:
		if (state->arg_num > 0)
			argp_usage(state);
		config_file = (char *)malloc((strlen(arg) + 1 ) * sizeof(char));
		strcpy(config_file, arg);
		break;
	case 'p':
		do_print_config = 1;
		break;
	case 'd':
		dryrun = 1;
		break;
	case 'q':
		quiet = 1;
		break;
	case 't':
		if (strcmp("madvise", arg) == 0) {
			hintmethod = MADVISE;
			break;
		}
		if (strcmp("mlock", arg) == 0) {
			hintmethod = MLOCK;
			break;
		}
		fprintf(stderr, "hint should be madvise or mlock, not %s\n",
				arg);
		return ARGP_ERR_UNKNOWN;
	case 'r':
		if (!strcmp("ro", arg)) {
			default_rw_mode = READ_ONLY;
			break;
		} else if (!strcmp("wo", arg)) {
			default_rw_mode = WRITE_ONLY;
			break;
		} else if (!strcmp("rw", arg)) {
			default_rw_mode = READ_WRITE;
			break;
		}
		fprintf(stderr, "wrong default_rwmode input %s\n", arg);
		return ARGP_ERR_UNKNOWN;
	case 'c':
		nr_repeats = atoi(arg);
		break;
	case 'h':
		use_hugetlb = 1;
		break;
	default:
		return ARGP_ERR_UNKNOWN;
	}

	return 0;
}

int main(int argc, char *argv[])
{
	struct access_config config;
	struct argp argp = {
		.options = options,
		.parser = parse_option,
		.args_doc = "[config file]",
		.doc = "Simulate given memory access pattern\v"
			"\'config file\' argument is optional."
			"  It defaults to \'configs/default\'",
	};
	int i;

	argp_parse(&argp, argc, argv, ARGP_IN_ORDER, NULL, NULL);
	setlocale(LC_NUMERIC, "");

	for (i = 0; i < nr_repeats; i++) {
		read_config(config_file, &config);
		if (do_print_config && !quiet) {
			pr_regions(config.regions, config.nr_regions);
			pr_phases(config.phases, config.nr_phases);
		}

		if (dryrun)
			return 0;

		init_rndints();
		exec_config(&config);
	}

	return 0;
}