/*
 * mem-memcpy.c
 *
 * memcpy: Simple memory copy in various ways
 *
 * Written by Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
 */

#include "../perf.h"
#include "../util/util.h"
#include "../util/parse-options.h"
#include "../util/header.h"
#include "../util/cloexec.h"
#include "bench.h"
#include "mem-memcpy-arch.h"
#include "mem-memset-arch.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <errno.h>

#define K 1024

static const char	*length_str	= "1MB";
static const char	*routine	= "default";
static int		iterations	= 1;
static bool		use_cycle;
static int		cycle_fd;
static bool		only_prefault;
static bool		no_prefault;

static const struct option options[] = {
	OPT_STRING('l', "length", &length_str, "1MB",
		    "Specify length of memory to copy. "
		    "Available units: B, KB, MB, GB and TB (upper and lower)"),
	OPT_STRING('r', "routine", &routine, "default",
		    "Specify routine to copy"),
	OPT_INTEGER('i', "iterations", &iterations,
		    "repeat memcpy() invocation this number of times"),
	OPT_BOOLEAN('c', "cycle", &use_cycle,
		    "Use cycles event instead of gettimeofday() for measuring"),
	OPT_BOOLEAN('o', "only-prefault", &only_prefault,
		    "Show only the result with page faults before memcpy()"),
	OPT_BOOLEAN('n', "no-prefault", &no_prefault,
		    "Show only the result without page faults before memcpy()"),
	OPT_END()
};

typedef void *(*memcpy_t)(void *, const void *, size_t);
typedef void *(*memset_t)(void *, int, size_t);

struct routine {
	const char *name;
	const char *desc;
	union {
		memcpy_t memcpy;
		memset_t memset;
	} fn;
};

struct routine memcpy_routines[] = {
	{ .name = "default",
	  .desc = "Default memcpy() provided by glibc",
	  .fn.memcpy = memcpy },
#ifdef HAVE_ARCH_X86_64_SUPPORT

#define MEMCPY_FN(_fn, _name, _desc) {.name = _name, .desc = _desc, .fn.memcpy = _fn},
#include "mem-memcpy-x86-64-asm-def.h"
#undef MEMCPY_FN

#endif

	{ NULL,
	  NULL,
	  {NULL}   }
};

static const char * const bench_mem_memcpy_usage[] = {
	"perf bench mem memcpy <options>",
	NULL
};

static struct perf_event_attr cycle_attr = {
	.type		= PERF_TYPE_HARDWARE,
	.config		= PERF_COUNT_HW_CPU_CYCLES
};

static void init_cycle(void)
{
	cycle_fd = sys_perf_event_open(&cycle_attr, getpid(), -1, -1,
				       perf_event_open_cloexec_flag());

	if (cycle_fd < 0 && errno == ENOSYS)
		die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
	else
		BUG_ON(cycle_fd < 0);
}

static u64 get_cycle(void)
{
	int ret;
	u64 clk;

	ret = read(cycle_fd, &clk, sizeof(u64));
	BUG_ON(ret != sizeof(u64));

	return clk;
}

static double timeval2double(struct timeval *ts)
{
	return (double)ts->tv_sec +
		(double)ts->tv_usec / (double)1000000;
}

#define pf (no_prefault ? 0 : 1)

#define print_bps(x) do {					\
		if (x < K)					\
			printf(" %14lf B/Sec", x);		\
		else if (x < K * K)				\
			printf(" %14lfd KB/Sec", x / K);	\
		else if (x < K * K * K)				\
			printf(" %14lf MB/Sec", x / K / K);	\
		else						\
			printf(" %14lf GB/Sec", x / K / K / K); \
	} while (0)

struct bench_mem_info {
	const struct routine *routines;
	u64 (*do_cycle)(const struct routine *r, size_t len, bool prefault);
	double (*do_gettimeofday)(const struct routine *r, size_t len, bool prefault);
	const char *const *usage;
};

static int bench_mem_common(int argc, const char **argv,
		     const char *prefix __maybe_unused,
		     struct bench_mem_info *info)
{
	int i;
	size_t len;
	double totallen;
	double result_bps[2];
	u64 result_cycle[2];

	argc = parse_options(argc, argv, options,
			     info->usage, 0);

	if (no_prefault && only_prefault) {
		fprintf(stderr, "Invalid options: -o and -n are mutually exclusive\n");
		return 1;
	}

	if (use_cycle)
		init_cycle();

	len = (size_t)perf_atoll((char *)length_str);
	totallen = (double)len * iterations;

	result_cycle[0] = result_cycle[1] = 0ULL;
	result_bps[0] = result_bps[1] = 0.0;

	if ((s64)len <= 0) {
		fprintf(stderr, "Invalid length:%s\n", length_str);
		return 1;
	}

	/* same to without specifying either of prefault and no-prefault */
	if (only_prefault && no_prefault)
		only_prefault = no_prefault = false;

	for (i = 0; info->routines[i].name; i++) {
		if (!strcmp(info->routines[i].name, routine))
			break;
	}
	if (!info->routines[i].name) {
		printf("Unknown routine:%s\n", routine);
		printf("Available routines...\n");
		for (i = 0; info->routines[i].name; i++) {
			printf("\t%s ... %s\n",
			       info->routines[i].name, info->routines[i].desc);
		}
		return 1;
	}

	if (bench_format == BENCH_FORMAT_DEFAULT)
		printf("# Copying %s Bytes ...\n\n", length_str);

	if (!only_prefault && !no_prefault) {
		/* show both of results */
		if (use_cycle) {
			result_cycle[0] =
				info->do_cycle(&info->routines[i], len, false);
			result_cycle[1] =
				info->do_cycle(&info->routines[i], len, true);
		} else {
			result_bps[0] =
				info->do_gettimeofday(&info->routines[i],
						len, false);
			result_bps[1] =
				info->do_gettimeofday(&info->routines[i],
						len, true);
		}
	} else {
		if (use_cycle) {
			result_cycle[pf] =
				info->do_cycle(&info->routines[i],
						len, only_prefault);
		} else {
			result_bps[pf] =
				info->do_gettimeofday(&info->routines[i],
						len, only_prefault);
		}
	}

	switch (bench_format) {
	case BENCH_FORMAT_DEFAULT:
		if (!only_prefault && !no_prefault) {
			if (use_cycle) {
				printf(" %14lf Cycle/Byte\n",
					(double)result_cycle[0]
					/ totallen);
				printf(" %14lf Cycle/Byte (with prefault)\n",
					(double)result_cycle[1]
					/ totallen);
			} else {
				print_bps(result_bps[0]);
				printf("\n");
				print_bps(result_bps[1]);
				printf(" (with prefault)\n");
			}
		} else {
			if (use_cycle) {
				printf(" %14lf Cycle/Byte",
					(double)result_cycle[pf]
					/ totallen);
			} else
				print_bps(result_bps[pf]);

			printf("%s\n", only_prefault ? " (with prefault)" : "");
		}
		break;
	case BENCH_FORMAT_SIMPLE:
		if (!only_prefault && !no_prefault) {
			if (use_cycle) {
				printf("%lf %lf\n",
					(double)result_cycle[0] / totallen,
					(double)result_cycle[1] / totallen);
			} else {
				printf("%lf %lf\n",
					result_bps[0], result_bps[1]);
			}
		} else {
			if (use_cycle) {
				printf("%lf\n", (double)result_cycle[pf]
					/ totallen);
			} else
				printf("%lf\n", result_bps[pf]);
		}
		break;
	default:
		/* reaching this means there's some disaster: */
		die("unknown format: %d\n", bench_format);
		break;
	}

	return 0;
}

static void memcpy_alloc_mem(void **dst, void **src, size_t length)
{
	*dst = zalloc(length);
	if (!*dst)
		die("memory allocation failed - maybe length is too large?\n");

	*src = zalloc(length);
	if (!*src)
		die("memory allocation failed - maybe length is too large?\n");
	/* Make sure to always replace the zero pages even if MMAP_THRESH is crossed */
	memset(*src, 0, length);
}

static u64 do_memcpy_cycle(const struct routine *r, size_t len, bool prefault)
{
	u64 cycle_start = 0ULL, cycle_end = 0ULL;
	void *src = NULL, *dst = NULL;
	memcpy_t fn = r->fn.memcpy;
	int i;

	memcpy_alloc_mem(&src, &dst, len);

	if (prefault)
		fn(dst, src, len);

	cycle_start = get_cycle();
	for (i = 0; i < iterations; ++i)
		fn(dst, src, len);
	cycle_end = get_cycle();

	free(src);
	free(dst);
	return cycle_end - cycle_start;
}

static double do_memcpy_gettimeofday(const struct routine *r, size_t len,
				     bool prefault)
{
	struct timeval tv_start, tv_end, tv_diff;
	memcpy_t fn = r->fn.memcpy;
	void *src = NULL, *dst = NULL;
	int i;

	memcpy_alloc_mem(&src, &dst, len);

	if (prefault)
		fn(dst, src, len);

	BUG_ON(gettimeofday(&tv_start, NULL));
	for (i = 0; i < iterations; ++i)
		fn(dst, src, len);
	BUG_ON(gettimeofday(&tv_end, NULL));

	timersub(&tv_end, &tv_start, &tv_diff);

	free(src);
	free(dst);
	return (double)(((double)len * iterations) / timeval2double(&tv_diff));
}

int bench_mem_memcpy(int argc, const char **argv,
		     const char *prefix __maybe_unused)
{
	struct bench_mem_info info = {
		.routines = memcpy_routines,
		.do_cycle = do_memcpy_cycle,
		.do_gettimeofday = do_memcpy_gettimeofday,
		.usage = bench_mem_memcpy_usage,
	};

	return bench_mem_common(argc, argv, prefix, &info);
}

static void memset_alloc_mem(void **dst, size_t length)
{
	*dst = zalloc(length);
	if (!*dst)
		die("memory allocation failed - maybe length is too large?\n");
}

static u64 do_memset_cycle(const struct routine *r, size_t len, bool prefault)
{
	u64 cycle_start = 0ULL, cycle_end = 0ULL;
	memset_t fn = r->fn.memset;
	void *dst = NULL;
	int i;

	memset_alloc_mem(&dst, len);

	if (prefault)
		fn(dst, -1, len);

	cycle_start = get_cycle();
	for (i = 0; i < iterations; ++i)
		fn(dst, i, len);
	cycle_end = get_cycle();

	free(dst);
	return cycle_end - cycle_start;
}

static double do_memset_gettimeofday(const struct routine *r, size_t len,
				     bool prefault)
{
	struct timeval tv_start, tv_end, tv_diff;
	memset_t fn = r->fn.memset;
	void *dst = NULL;
	int i;

	memset_alloc_mem(&dst, len);

	if (prefault)
		fn(dst, -1, len);

	BUG_ON(gettimeofday(&tv_start, NULL));
	for (i = 0; i < iterations; ++i)
		fn(dst, i, len);
	BUG_ON(gettimeofday(&tv_end, NULL));

	timersub(&tv_end, &tv_start, &tv_diff);

	free(dst);
	return (double)(((double)len * iterations) / timeval2double(&tv_diff));
}

static const char * const bench_mem_memset_usage[] = {
	"perf bench mem memset <options>",
	NULL
};

static const struct routine memset_routines[] = {
	{ .name ="default",
	  .desc = "Default memset() provided by glibc",
	  .fn.memset = memset },
#ifdef HAVE_ARCH_X86_64_SUPPORT

#define MEMSET_FN(_fn, _name, _desc) { .name = _name, .desc = _desc, .fn.memset = _fn },
#include "mem-memset-x86-64-asm-def.h"
#undef MEMSET_FN

#endif

	{ .name = NULL,
	  .desc = NULL,
	  .fn.memset = NULL   }
};

int bench_mem_memset(int argc, const char **argv,
		     const char *prefix __maybe_unused)
{
	struct bench_mem_info info = {
		.routines = memset_routines,
		.do_cycle = do_memset_cycle,
		.do_gettimeofday = do_memset_gettimeofday,
		.usage = bench_mem_memset_usage,
	};

	return bench_mem_common(argc, argv, prefix, &info);
}