[fio.git] / blktrace.c

/*
 * blktrace support code for fio
 */
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <dirent.h>

#include "flist.h"
#include "fio.h"
#include "blktrace_api.h"

#define TRACE_FIFO_SIZE	8192

/*
 * fifo refill frontend, to avoid reading data in trace sized bites
 */
static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd)
{
	char buf[TRACE_FIFO_SIZE];
	unsigned int total;
	int ret;

	total = sizeof(buf);
	if (total > fifo_room(fifo))
		total = fifo_room(fifo);

	ret = read(fd, buf, total);
	if (ret < 0) {
		td_verror(td, errno, "read blktrace file");
		return -1;
	}

	if (ret > 0)
		ret = fifo_put(fifo, buf, ret);

	dprint(FD_BLKTRACE, "refill: filled %d bytes\n", ret);
	return ret;
}

/*
 * Retrieve 'len' bytes from the fifo, refilling if necessary.
 */
static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd,
			  void *buf, unsigned int len)
{
	if (fifo_len(fifo) < len) {
		int ret = refill_fifo(td, fifo, fd);

		if (ret < 0)
			return ret;
	}

	return fifo_get(fifo, buf, len);
}

/*
 * Just discard the pdu by seeking past it.
 */
static int discard_pdu(struct thread_data *td, struct fifo *fifo, int fd,
		       struct blk_io_trace *t)
{
	if (t->pdu_len == 0)
		return 0;

	dprint(FD_BLKTRACE, "discard pdu len %u\n", t->pdu_len);
	return trace_fifo_get(td, fifo, fd, NULL, t->pdu_len);
}

/*
 * Check if this is a blktrace binary data file. We read a single trace
 * into memory and check for the magic signature.
 */
int is_blktrace(const char *filename)
{
	struct blk_io_trace t;
	int fd, ret;

	fd = open(filename, O_RDONLY);
	if (fd < 0)
		return 0;

	ret = read(fd, &t, sizeof(t));
	close(fd);

	if (ret < 0) {
		perror("read blktrace");
		return 0;
	} else if (ret != sizeof(t)) {
		log_err("fio: short read on blktrace file\n");
		return 0;
	}

	if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC)
		return 1;

	return 0;
}

static int lookup_device(char *path, unsigned int maj, unsigned int min)
{
	struct dirent *dir;
	struct stat st;
	int found = 0;
	DIR *D;

	D = opendir(path);
	if (!D)
		return 0;

	while ((dir = readdir(D)) != NULL) {
		char full_path[256];

		if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."))
			continue;

		sprintf(full_path, "%s/%s", path, dir->d_name);
		if (lstat(full_path, &st) == -1) {
			perror("lstat");
			break;
		}

		if (S_ISDIR(st.st_mode)) {
			found = lookup_device(full_path, maj, min);
			if (found) {
				strcpy(path, full_path);
				break;
			}
		}

		if (!S_ISBLK(st.st_mode))
			continue;

		if (maj == major(st.st_rdev) && min == minor(st.st_rdev)) {
			dprint(FD_BLKTRACE, "device lookup: %d/%d\n", maj, min);
			strcpy(path, full_path);
			found = 1;
			break;
		}
	}

	closedir(D);
	return found;
}

#define FMINORBITS	20
#define FMINORMASK	((1U << FMINORBITS) - 1)
#define FMAJOR(dev)	((unsigned int) ((dev) >> FMINORBITS))
#define FMINOR(dev)	((unsigned int) ((dev) & FMINORMASK))

static void trace_add_open_event(struct thread_data *td, int fileno)
{
	struct io_piece *ipo;

	ipo = calloc(1, sizeof(*ipo));

	ipo->ddir = DDIR_INVAL;
	ipo->fileno = fileno;
	ipo->file_action = FIO_LOG_OPEN_FILE;
	flist_add_tail(&ipo->list, &td->io_log_list);
}

static void trace_add_file(struct thread_data *td, __u32 device)
{
	static unsigned int last_maj, last_min;
	unsigned int maj = FMAJOR(device);
	unsigned int min = FMINOR(device);
	struct fio_file *f;
	char dev[256];
	unsigned int i;

	if (last_maj == maj && last_min == min)
		return;

	last_maj = maj;
	last_min = min;

	/*
	 * check for this file in our list
	 */
	for_each_file(td, f, i)
		if (f->major == maj && f->minor == min)
			return;

	strcpy(dev, "/dev");
	if (lookup_device(dev, maj, min)) {
		int fileno;

		dprint(FD_BLKTRACE, "add devices %s\n", dev);
		fileno = add_file_exclusive(td, dev);
		trace_add_open_event(td, fileno);
	}
}

/*
 * Store blk_io_trace data in an ipo for later retrieval.
 */
static void store_ipo(struct thread_data *td, unsigned long long offset,
		      unsigned int bytes, int rw, unsigned long long ttime)
{
	struct io_piece *ipo = malloc(sizeof(*ipo));

	memset(ipo, 0, sizeof(*ipo));
	INIT_FLIST_HEAD(&ipo->list);
	/*
	 * the 512 is wrong here, it should be the hardware sector size...
	 */
	ipo->offset = offset * 512;
	ipo->len = bytes;
	ipo->delay = ttime / 1000;
	if (rw)
		ipo->ddir = DDIR_WRITE;
	else
		ipo->ddir = DDIR_READ;

	dprint(FD_BLKTRACE, "store ddir=%d, off=%llu, len=%lu, delay=%lu\n",
							ipo->ddir, ipo->offset,
							ipo->len, ipo->delay);
	queue_io_piece(td, ipo);
}

static void handle_trace_notify(struct blk_io_trace *t)
{
	switch (t->action) {
	case BLK_TN_PROCESS:
		printf("got process notify: %x, %d\n", t->action, t->pid);
		break;
	case BLK_TN_TIMESTAMP:
		printf("got timestamp notify: %x, %d\n", t->action, t->pid);
		break;
	case BLK_TN_MESSAGE:
		break;
	default:
		dprint(FD_BLKTRACE, "unknown trace act %x\n", t->action);
		break;
	}
}

static void handle_trace_discard(struct thread_data *td, struct blk_io_trace *t,
				 unsigned long long ttime, unsigned long *ios)
{
	struct io_piece *ipo = malloc(sizeof(*ipo));

	trace_add_file(td, t->device);

	ios[DDIR_WRITE]++;
	td->o.size += t->bytes;

	memset(ipo, 0, sizeof(*ipo));
	INIT_FLIST_HEAD(&ipo->list);

	/*
	 * the 512 is wrong here, it should be the hardware sector size...
	 */
	ipo->offset = t->sector * 512;
	ipo->len = t->bytes;
	ipo->delay = ttime / 1000;
	ipo->ddir = DDIR_TRIM;

	dprint(FD_BLKTRACE, "store discard, off=%llu, len=%lu, delay=%lu\n",
							ipo->offset, ipo->len,
							ipo->delay);
	queue_io_piece(td, ipo);
}

static void handle_trace_fs(struct thread_data *td, struct blk_io_trace *t,
			    unsigned long long ttime, unsigned long *ios,
			    unsigned int *bs)
{
	int rw;

	trace_add_file(td, t->device);

	rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;

	if (t->bytes > bs[rw])
		bs[rw] = t->bytes;

	ios[rw]++;
	td->o.size += t->bytes;
	store_ipo(td, t->sector, t->bytes, rw, ttime);
}

/*
 * We only care for queue traces, most of the others are side effects
 * due to internal workings of the block layer.
 */
static void handle_trace(struct thread_data *td, struct blk_io_trace *t,
			 unsigned long long ttime, unsigned long *ios,
			 unsigned int *bs)
{
	if ((t->action & 0xffff) != __BLK_TA_QUEUE)
		return;
	if (t->action & BLK_TC_ACT(BLK_TC_PC))
		return;

	if (t->action & BLK_TC_ACT(BLK_TC_NOTIFY))
		handle_trace_notify(t);
	else if (t->action & BLK_TC_ACT(BLK_TC_DISCARD))
		handle_trace_discard(td, t, ttime, ios);
	else
		handle_trace_fs(td, t, ttime, ios, bs);
}

/*
 * Load a blktrace file by reading all the blk_io_trace entries, and storing
 * them as io_pieces like the fio text version would do.
 */
int load_blktrace(struct thread_data *td, const char *filename)
{
	unsigned long long ttime, delay;
	struct blk_io_trace t;
	unsigned long ios[2], skipped_writes;
	unsigned int cpu;
	unsigned int rw_bs[2];
	struct fifo *fifo;
	int fd;

	fd = open(filename, O_RDONLY);
	if (fd < 0) {
		td_verror(td, errno, "open blktrace file");
		return 1;
	}

	fifo = fifo_alloc(TRACE_FIFO_SIZE);

	td->o.size = 0;

	cpu = 0;
	ttime = 0;
	ios[0] = ios[1] = 0;
	rw_bs[0] = rw_bs[1] = 0;
	skipped_writes = 0;
	do {
		int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));

		if (ret < 0)
			goto err;
		else if (!ret)
			break;
		else if (ret < (int) sizeof(t)) {
			log_err("fio: short fifo get\n");
			break;
		}

		if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
			log_err("fio: bad magic in blktrace data: %x\n",
								t.magic);
			goto err;
		}
		if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) {
			log_err("fio: bad blktrace version %d\n",
								t.magic & 0xff);
			goto err;
		}
		ret = discard_pdu(td, fifo, fd, &t);
		if (ret < 0) {
			td_verror(td, ret, "blktrace lseek");
			goto err;
		} else if (t.pdu_len != ret) {
			log_err("fio: discarded %d of %d\n", ret, t.pdu_len);
			goto err;
		}
		if ((t.action & BLK_TC_ACT(BLK_TC_NOTIFY)) == 0) {
			if (!ttime) {
				ttime = t.time;
				cpu = t.cpu;
			}

			delay = 0;
			if (cpu == t.cpu)
				delay = t.time - ttime;
			if ((t.action & BLK_TC_ACT(BLK_TC_WRITE)) && read_only)
				skipped_writes++;
			else {
				/*
				 * set delay to zero if no_stall enabled for
				 * fast replay
				 */
				if (td->o.no_stall)
					delay = 0;

				handle_trace(td, &t, delay, ios, rw_bs);
			}

			ttime = t.time;
			cpu = t.cpu;
		} else {
			delay = 0;
			handle_trace(td, &t, delay, ios, rw_bs);
		}
	} while (1);

	fifo_free(fifo);
	close(fd);

	if (skipped_writes)
		log_err("fio: %s skips replay of %lu writes due to read-only\n",
						td->o.name, skipped_writes);

	if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) {
		log_err("fio: found no ios in blktrace data\n");
		return 1;
	} else if (ios[DDIR_READ] && !ios[DDIR_READ]) {
		td->o.td_ddir = TD_DDIR_READ;
		td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
	} else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) {
		td->o.td_ddir = TD_DDIR_WRITE;
		td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
	} else {
		td->o.td_ddir = TD_DDIR_RW;
		td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
		td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
	}

	/*
	 * We need to do direct/raw ios to the device, to avoid getting
	 * read-ahead in our way.
	 */
	td->o.odirect = 1;

	return 0;
err:
	close(fd);
	fifo_free(fifo);
	return 1;
}
Commit	Line	Data
fb7b71a3 JA	1	/*
	2	* blktrace support code for fio
	3	*/
	4	#include <stdio.h>
	5	#include <stdlib.h>
5e6c2067 JA	6	#include <sys/stat.h>
5e6c2067 JA	7	#include <dirent.h>
8c1fdf04	8
01743ee1	9	#include "flist.h"
fb7b71a3 JA	10	#include "fio.h"
	11	#include "blktrace_api.h"
	12
2da7df1d	13	#define TRACE_FIFO_SIZE 8192
e2887563 JA	14
	15	/*
	16	* fifo refill frontend, to avoid reading data in trace sized bites
	17	*/
	18	static int refill_fifo(struct thread_data td, struct fifo fifo, int fd)
	19	{
	20	char buf[TRACE_FIFO_SIZE];
f12b323f	21	unsigned int total;
e2887563 JA	22	int ret;
e2887563 JA	23
f12b323f JA	24	total = sizeof(buf);
	25	if (total > fifo_room(fifo))
	26	total = fifo_room(fifo);
e2887563	27
f12b323f JA	28	ret = read(fd, buf, total);
	29	if (ret < 0) {
	30	td_verror(td, errno, "read blktrace file");
	31	return -1;
e2887563 JA	32	}
e2887563 JA	33
f12b323f JA	34	if (ret > 0)
	35	ret = fifo_put(fifo, buf, ret);
	36
bd6f78b2	37	dprint(FD_BLKTRACE, "refill: filled %d bytes\n", ret);
f12b323f	38	return ret;
e2887563 JA	39	}
	40
	41	/*
	42	* Retrieve 'len' bytes from the fifo, refilling if necessary.
	43	*/
	44	static int trace_fifo_get(struct thread_data td, struct fifo fifo, int fd,
	45	void *buf, unsigned int len)
	46	{
f12b323f JA	47	if (fifo_len(fifo) < len) {
f12b323f JA	48	int ret = refill_fifo(td, fifo, fd);
e2887563	49
f12b323f JA	50	if (ret < 0)
	51	return ret;
	52	}
e2887563 JA	53
	54	return fifo_get(fifo, buf, len);
	55	}
	56
8c1fdf04 JA	57	/*
	58	* Just discard the pdu by seeking past it.
	59	*/
f12b323f JA	60	static int discard_pdu(struct thread_data td, struct fifo fifo, int fd,
f12b323f JA	61	struct blk_io_trace *t)
fb7b71a3 JA	62	{
	63	if (t->pdu_len == 0)
	64	return 0;
	65
bd6f78b2	66	dprint(FD_BLKTRACE, "discard pdu len %u\n", t->pdu_len);
f12b323f	67	return trace_fifo_get(td, fifo, fd, NULL, t->pdu_len);
fb7b71a3 JA	68	}
fb7b71a3 JA	69
8c1fdf04 JA	70	/*
	71	* Check if this is a blktrace binary data file. We read a single trace
	72	* into memory and check for the magic signature.
	73	*/
fb7b71a3 JA	74	int is_blktrace(const char *filename)
	75	{
	76	struct blk_io_trace t;
	77	int fd, ret;
	78
	79	fd = open(filename, O_RDONLY);
4dced407	80	if (fd < 0)
fb7b71a3	81	return 0;
fb7b71a3 JA	82
	83	ret = read(fd, &t, sizeof(t));
	84	close(fd);
	85
	86	if (ret < 0) {
	87	perror("read blktrace");
	88	return 0;
	89	} else if (ret != sizeof(t)) {
	90	log_err("fio: short read on blktrace file\n");
	91	return 0;
	92	}
	93
	94	if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC)
	95	return 1;
	96
	97	return 0;
	98	}
	99
5e6c2067 JA	100	static int lookup_device(char *path, unsigned int maj, unsigned int min)
	101	{
	102	struct dirent *dir;
	103	struct stat st;
	104	int found = 0;
	105	DIR *D;
	106
	107	D = opendir(path);
	108	if (!D)
	109	return 0;
	110
	111	while ((dir = readdir(D)) != NULL) {
	112	char full_path[256];
	113
	114	if (!strcmp(dir->d_name, ".") \|\| !strcmp(dir->d_name, ".."))
	115	continue;
	116
	117	sprintf(full_path, "%s/%s", path, dir->d_name);
	118	if (lstat(full_path, &st) == -1) {
	119	perror("lstat");
	120	break;
	121	}
	122
	123	if (S_ISDIR(st.st_mode)) {
	124	found = lookup_device(full_path, maj, min);
	125	if (found) {
	126	strcpy(path, full_path);
	127	break;
	128	}
	129	}
	130
	131	if (!S_ISBLK(st.st_mode))
	132	continue;
	133
	134	if (maj == major(st.st_rdev) && min == minor(st.st_rdev)) {
5ec10eaa	135	dprint(FD_BLKTRACE, "device lookup: %d/%d\n", maj, min);
5e6c2067 JA	136	strcpy(path, full_path);
	137	found = 1;
	138	break;
	139	}
	140	}
	141
	142	closedir(D);
	143	return found;
	144	}
	145
c69aa91f JA	146	#define FMINORBITS 20
	147	#define FMINORMASK ((1U << FMINORBITS) - 1)
	148	#define FMAJOR(dev) ((unsigned int) ((dev) >> FMINORBITS))
	149	#define FMINOR(dev) ((unsigned int) ((dev) & FMINORMASK))
eeb9c2aa	150
691c8fb0 JA	151	static void trace_add_open_event(struct thread_data *td, int fileno)
	152	{
	153	struct io_piece *ipo;
	154
	155	ipo = calloc(1, sizeof(*ipo));
	156
	157	ipo->ddir = DDIR_INVAL;
	158	ipo->fileno = fileno;
	159	ipo->file_action = FIO_LOG_OPEN_FILE;
01743ee1	160	flist_add_tail(&ipo->list, &td->io_log_list);
691c8fb0 JA	161	}
691c8fb0 JA	162
5e6c2067 JA	163	static void trace_add_file(struct thread_data *td, __u32 device)
	164	{
	165	static unsigned int last_maj, last_min;
c69aa91f JA	166	unsigned int maj = FMAJOR(device);
c69aa91f JA	167	unsigned int min = FMINOR(device);
5e6c2067 JA	168	struct fio_file *f;
	169	char dev[256];
	170	unsigned int i;
	171
	172	if (last_maj == maj && last_min == min)
	173	return;
	174
	175	last_maj = maj;
	176	last_min = min;
	177
	178	/*
	179	* check for this file in our list
	180	*/
	181	for_each_file(td, f, i)
	182	if (f->major == maj && f->minor == min)
	183	return;
	184
	185	strcpy(dev, "/dev");
bd6f78b2	186	if (lookup_device(dev, maj, min)) {
691c8fb0 JA	187	int fileno;
691c8fb0 JA	188
bd6f78b2	189	dprint(FD_BLKTRACE, "add devices %s\n", dev);
49ffb4a2	190	fileno = add_file_exclusive(td, dev);
691c8fb0	191	trace_add_open_event(td, fileno);
bd6f78b2	192	}
5e6c2067 JA	193	}
5e6c2067 JA	194
8c1fdf04 JA	195	/*
	196	* Store blk_io_trace data in an ipo for later retrieval.
	197	*/
fdefd987	198	static void store_ipo(struct thread_data *td, unsigned long long offset,
8c1fdf04	199	unsigned int bytes, int rw, unsigned long long ttime)
fdefd987 JA	200	{
	201	struct io_piece ipo = malloc(sizeof(ipo));
	202
	203	memset(ipo, 0, sizeof(*ipo));
01743ee1	204	INIT_FLIST_HEAD(&ipo->list);
a2eea81b JA	205	/*
	206	* the 512 is wrong here, it should be the hardware sector size...
	207	*/
	208	ipo->offset = offset * 512;
fdefd987	209	ipo->len = bytes;
8c1fdf04	210	ipo->delay = ttime / 1000;
fdefd987 JA	211	if (rw)
	212	ipo->ddir = DDIR_WRITE;
	213	else
	214	ipo->ddir = DDIR_READ;
	215
bd6f78b2 JA	216	dprint(FD_BLKTRACE, "store ddir=%d, off=%llu, len=%lu, delay=%lu\n",
	217	ipo->ddir, ipo->offset,
	218	ipo->len, ipo->delay);
691c8fb0	219	queue_io_piece(td, ipo);
fdefd987 JA	220	}
fdefd987 JA	221
0b9d69ec	222	static void handle_trace_notify(struct blk_io_trace *t)
cd991b9e	223	{
691c8fb0 JA	224	switch (t->action) {
	225	case BLK_TN_PROCESS:
	226	printf("got process notify: %x, %d\n", t->action, t->pid);
	227	break;
	228	case BLK_TN_TIMESTAMP:
	229	printf("got timestamp notify: %x, %d\n", t->action, t->pid);
	230	break;
ff58fced JA	231	case BLK_TN_MESSAGE:
ff58fced JA	232	break;
691c8fb0 JA	233	default:
	234	dprint(FD_BLKTRACE, "unknown trace act %x\n", t->action);
	235	break;
	236	}
	237	}
5b3023b8	238
ff58fced JA	239	static void handle_trace_discard(struct thread_data td, struct blk_io_trace t,
	240	unsigned long long ttime, unsigned long *ios)
	241	{
	242	struct io_piece ipo = malloc(sizeof(ipo));
	243
	244	trace_add_file(td, t->device);
	245
	246	ios[DDIR_WRITE]++;
	247	td->o.size += t->bytes;
	248
	249	memset(ipo, 0, sizeof(*ipo));
	250	INIT_FLIST_HEAD(&ipo->list);
	251
	252	/*
	253	* the 512 is wrong here, it should be the hardware sector size...
	254	*/
	255	ipo->offset = t->sector * 512;
	256	ipo->len = t->bytes;
	257	ipo->delay = ttime / 1000;
	258	ipo->ddir = DDIR_TRIM;
	259
	260	dprint(FD_BLKTRACE, "store discard, off=%llu, len=%lu, delay=%lu\n",
	261	ipo->offset, ipo->len,
	262	ipo->delay);
	263	queue_io_piece(td, ipo);
	264	}
	265
691c8fb0 JA	266	static void handle_trace_fs(struct thread_data td, struct blk_io_trace t,
	267	unsigned long long ttime, unsigned long *ios,
	268	unsigned int *bs)
	269	{
	270	int rw;
5b3023b8 JA	271
	272	trace_add_file(td, t->device);
	273
	274	rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;
	275
	276	if (t->bytes > bs[rw])
	277	bs[rw] = t->bytes;
	278
	279	ios[rw]++;
	280	td->o.size += t->bytes;
	281	store_ipo(td, t->sector, t->bytes, rw, ttime);
cd991b9e JA	282	}
cd991b9e JA	283
691c8fb0 JA	284	/*
	285	* We only care for queue traces, most of the others are side effects
	286	* due to internal workings of the block layer.
	287	*/
	288	static void handle_trace(struct thread_data td, struct blk_io_trace t,
	289	unsigned long long ttime, unsigned long *ios,
	290	unsigned int *bs)
	291	{
	292	if ((t->action & 0xffff) != __BLK_TA_QUEUE)
	293	return;
	294	if (t->action & BLK_TC_ACT(BLK_TC_PC))
	295	return;
	296
	297	if (t->action & BLK_TC_ACT(BLK_TC_NOTIFY))
aec2de20	298	handle_trace_notify(t);
ff58fced JA	299	else if (t->action & BLK_TC_ACT(BLK_TC_DISCARD))
ff58fced JA	300	handle_trace_discard(td, t, ttime, ios);
691c8fb0 JA	301	else
	302	handle_trace_fs(td, t, ttime, ios, bs);
	303	}
	304
8c1fdf04 JA	305	/*
	306	* Load a blktrace file by reading all the blk_io_trace entries, and storing
	307	* them as io_pieces like the fio text version would do.
	308	*/
fb7b71a3 JA	309	int load_blktrace(struct thread_data td, const char filename)
fb7b71a3 JA	310	{
a61eddec	311	unsigned long long ttime, delay;
fb7b71a3	312	struct blk_io_trace t;
4241ea8f	313	unsigned long ios[2], skipped_writes;
a61eddec	314	unsigned int cpu;
d84f8d49	315	unsigned int rw_bs[2];
e2887563	316	struct fifo *fifo;
fb7b71a3 JA	317	int fd;
	318
	319	fd = open(filename, O_RDONLY);
	320	if (fd < 0) {
	321	td_verror(td, errno, "open blktrace file");
	322	return 1;
	323	}
	324
e2887563 JA	325	fifo = fifo_alloc(TRACE_FIFO_SIZE);
e2887563 JA	326
6df8adaa JA	327	td->o.size = 0;
6df8adaa JA	328
a61eddec	329	cpu = 0;
d84f8d49 JA	330	ttime = 0;
	331	ios[0] = ios[1] = 0;
	332	rw_bs[0] = rw_bs[1] = 0;
4241ea8f	333	skipped_writes = 0;
fb7b71a3	334	do {
e2887563	335	int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));
fb7b71a3	336
e2887563	337	if (ret < 0)
8c1fdf04	338	goto err;
e2887563 JA	339	else if (!ret)
	340	break;
	341	else if (ret < (int) sizeof(t)) {
	342	log_err("fio: short fifo get\n");
fb7b71a3	343	break;
fb7b71a3 JA	344	}
	345
	346	if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
5ec10eaa JA	347	log_err("fio: bad magic in blktrace data: %x\n",
5ec10eaa JA	348	t.magic);
8c1fdf04	349	goto err;
fb7b71a3 JA	350	}
fb7b71a3 JA	351	if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) {
5ec10eaa JA	352	log_err("fio: bad blktrace version %d\n",
5ec10eaa JA	353	t.magic & 0xff);
8c1fdf04	354	goto err;
fb7b71a3	355	}
f12b323f JA	356	ret = discard_pdu(td, fifo, fd, &t);
f12b323f JA	357	if (ret < 0) {
fb7b71a3	358	td_verror(td, ret, "blktrace lseek");
8c1fdf04	359	goto err;
f12b323f JA	360	} else if (t.pdu_len != ret) {
	361	log_err("fio: discarded %d of %d\n", ret, t.pdu_len);
	362	goto err;
fb7b71a3	363	}
691c8fb0 JA	364	if ((t.action & BLK_TC_ACT(BLK_TC_NOTIFY)) == 0) {
	365	if (!ttime) {
	366	ttime = t.time;
	367	cpu = t.cpu;
	368	}
	369
	370	delay = 0;
	371	if (cpu == t.cpu)
	372	delay = t.time - ttime;
	373	if ((t.action & BLK_TC_ACT(BLK_TC_WRITE)) && read_only)
	374	skipped_writes++;
64bbb865 DN	375	else {
	376	/*
	377	* set delay to zero if no_stall enabled for
	378	* fast replay
	379	*/
	380	if (td->o.no_stall)
	381	delay = 0;
	382
691c8fb0	383	handle_trace(td, &t, delay, ios, rw_bs);
64bbb865	384	}
691c8fb0	385
8c1fdf04	386	ttime = t.time;
a61eddec	387	cpu = t.cpu;
a6edd638 JA	388	} else {
a6edd638 JA	389	delay = 0;
4241ea8f	390	handle_trace(td, &t, delay, ios, rw_bs);
a6edd638	391	}
fb7b71a3 JA	392	} while (1);
fb7b71a3 JA	393
38470f85	394	fifo_free(fifo);
fb7b71a3	395	close(fd);
8c1fdf04	396
4241ea8f	397	if (skipped_writes)
5ec10eaa JA	398	log_err("fio: %s skips replay of %lu writes due to read-only\n",
5ec10eaa JA	399	td->o.name, skipped_writes);
4241ea8f	400
8c1fdf04 JA	401	if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) {
	402	log_err("fio: found no ios in blktrace data\n");
	403	return 1;
d84f8d49	404	} else if (ios[DDIR_READ] && !ios[DDIR_READ]) {
8c1fdf04	405	td->o.td_ddir = TD_DDIR_READ;
d84f8d49 JA	406	td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
d84f8d49 JA	407	} else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) {
8c1fdf04	408	td->o.td_ddir = TD_DDIR_WRITE;
d84f8d49 JA	409	td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
d84f8d49 JA	410	} else {
8c1fdf04	411	td->o.td_ddir = TD_DDIR_RW;
d84f8d49 JA	412	td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
	413	td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
	414	}
8c1fdf04 JA	415
	416	/*
	417	* We need to do direct/raw ios to the device, to avoid getting
	418	* read-ahead in our way.
	419	*/
	420	td->o.odirect = 1;
	421
fb7b71a3	422	return 0;
8c1fdf04 JA	423	err:
8c1fdf04 JA	424	close(fd);
38470f85	425	fifo_free(fifo);
8c1fdf04	426	return 1;
fb7b71a3	427	}