[blktrace.git] / btt / mmap.c

/*
 * blktrace output analysis: generate a timeline & gather statistics
 *
 * Copyright (C) 2006 Alan D. Brunelle <Alan.Brunelle@hp.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <string.h>

#include "blktrace.h"
#include "globals.h"

#define DEF_LEN	(16 * 1024 * 1024)

static int fd;
static void *cur_map = MAP_FAILED;
static off_t cur_min, cur, cur_max, total_size;
static size_t len;
static struct blk_io_trace *next_t;
static long pgsz;

int data_is_native = -1;

static inline size_t min_len(size_t a, size_t b)
{
	return a < b ? a : b;
}

static inline size_t convert_to_cpu(struct blk_io_trace *t,
                                    struct blk_io_trace *tp,
				    void **pdu)
{
	if (data_is_native == -1)
		check_data_endianness(t->magic);

	if (data_is_native)
		memcpy(tp, t, sizeof(*tp));
	else {
		tp->magic	= be32_to_cpu(t->magic);
		tp->sequence	= be32_to_cpu(t->sequence);
		tp->time	= be64_to_cpu(t->time);
		tp->sector	= be64_to_cpu(t->sector);
		tp->bytes	= be32_to_cpu(t->bytes);
		tp->action	= be32_to_cpu(t->action);
		tp->pid		= be32_to_cpu(t->pid);
		tp->device	= be32_to_cpu(t->device);
		tp->cpu		= be16_to_cpu(t->cpu);
		tp->error	= be16_to_cpu(t->error);
		tp->pdu_len	= be16_to_cpu(t->pdu_len);
	}

	if (tp->pdu_len) {
		*pdu = malloc(tp->pdu_len);
		memcpy(*pdu, t+1, tp->pdu_len);
	} else
		*pdu = NULL;

	return sizeof(*tp) + tp->pdu_len;
}

static int move_map(void)
{
	if (cur_map != MAP_FAILED)
		munmap(cur_map, len);

	cur_min = (cur & ~(pgsz-1));
	len = min_len(DEF_LEN, total_size - cur_min);
	if (len < sizeof(*next_t))
		return 0;

	cur_map = mmap(NULL, len, PROT_READ, MAP_SHARED, fd,
		       cur_min);
	if (cur_map == MAP_FAILED) {
		perror("mmap");
		exit(1);
	}

	cur_max = cur_min + len;
	return (cur < cur_max);
}

void setup_ifile(char *fname)
{
	struct stat buf;

	pgsz = sysconf(_SC_PAGESIZE);

	fd = my_open(fname, O_RDONLY);
	if (fd < 0) {
		perror(fname);
		exit(1);
	}
	if (fstat(fd, &buf) < 0) {
		perror(fname);
		exit(1);
	}
	total_size = buf.st_size;

	if (!move_map())
		exit(0);
}

void cleanup_ifile(void)
{
	if (cur_map != MAP_FAILED)
		munmap(cur_map, len);
	close(fd);
}

int next_trace(struct blk_io_trace *t, void **pdu)
{
	size_t this_len;

	if ((cur + 512) > cur_max)
		if (!move_map()) {
			cleanup_ifile();
			return 0;
		}

	next_t = cur_map + (cur - cur_min);
	this_len = convert_to_cpu(next_t, t, pdu);
	cur += this_len;

	return 1;
}

double pct_done(void)
{
	return 100.0 * ((double)cur / (double)total_size);
}
Commit	Line	Data
d76c5b81 AB	1	/*
	2	* blktrace output analysis: generate a timeline & gather statistics
	3	*
	4	* Copyright (C) 2006 Alan D. Brunelle <Alan.Brunelle@hp.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*
	20	*/
	21
	22	#include <stdio.h>
	23	#include <unistd.h>
	24	#include <sys/types.h>
	25	#include <sys/stat.h>
	26	#include <fcntl.h>
d76c5b81 AB	27	#include <sys/mman.h>
	28	#include <string.h>
	29
	30	#include "blktrace.h"
e6855475	31	#include "globals.h"
d76c5b81 AB	32
	33	#define DEF_LEN (16 * 1024 * 1024)
	34
	35	static int fd;
	36	static void *cur_map = MAP_FAILED;
	37	static off_t cur_min, cur, cur_max, total_size;
	38	static size_t len;
	39	static struct blk_io_trace *next_t;
	40	static long pgsz;
	41
	42	int data_is_native = -1;
	43
c053af42 AB	44	static inline size_t min_len(size_t a, size_t b)
	45	{
	46	return a < b ? a : b;
	47	}
d76c5b81	48
8b10aae0 AB	49	static inline size_t convert_to_cpu(struct blk_io_trace *t,
8b10aae0 AB	50	struct blk_io_trace *tp,
d76c5b81 AB	51	void **pdu)
	52	{
	53	if (data_is_native == -1)
	54	check_data_endianness(t->magic);
	55
	56	if (data_is_native)
	57	memcpy(tp, t, sizeof(*tp));
	58	else {
	59	tp->magic = be32_to_cpu(t->magic);
	60	tp->sequence = be32_to_cpu(t->sequence);
	61	tp->time = be64_to_cpu(t->time);
	62	tp->sector = be64_to_cpu(t->sector);
	63	tp->bytes = be32_to_cpu(t->bytes);
	64	tp->action = be32_to_cpu(t->action);
	65	tp->pid = be32_to_cpu(t->pid);
	66	tp->device = be32_to_cpu(t->device);
	67	tp->cpu = be16_to_cpu(t->cpu);
	68	tp->error = be16_to_cpu(t->error);
	69	tp->pdu_len = be16_to_cpu(t->pdu_len);
	70	}
	71
d76c5b81 AB	72	if (tp->pdu_len) {
	73	*pdu = malloc(tp->pdu_len);
	74	memcpy(*pdu, t+1, tp->pdu_len);
c053af42	75	} else
d76c5b81 AB	76	*pdu = NULL;
	77
	78	return sizeof(*tp) + tp->pdu_len;
	79	}
	80
	81	static int move_map(void)
	82	{
	83	if (cur_map != MAP_FAILED)
	84	munmap(cur_map, len);
	85
	86	cur_min = (cur & ~(pgsz-1));
	87	len = min_len(DEF_LEN, total_size - cur_min);
	88	if (len < sizeof(*next_t))
	89	return 0;
	90
	91	cur_map = mmap(NULL, len, PROT_READ, MAP_SHARED, fd,
	92	cur_min);
	93	if (cur_map == MAP_FAILED) {
	94	perror("mmap");
	95	exit(1);
	96	}
	97
	98	cur_max = cur_min + len;
	99	return (cur < cur_max);
	100	}
	101
	102	void setup_ifile(char *fname)
	103	{
	104	struct stat buf;
	105
	106	pgsz = sysconf(_SC_PAGESIZE);
	107
e6855475	108	fd = my_open(fname, O_RDONLY);
d76c5b81 AB	109	if (fd < 0) {
	110	perror(fname);
	111	exit(1);
	112	}
	113	if (fstat(fd, &buf) < 0) {
	114	perror(fname);
	115	exit(1);
	116	}
	117	total_size = buf.st_size;
	118
	119	if (!move_map())
	120	exit(0);
	121	}
	122
	123	void cleanup_ifile(void)
	124	{
	125	if (cur_map != MAP_FAILED)
	126	munmap(cur_map, len);
	127	close(fd);
	128	}
	129
	130	int next_trace(struct blk_io_trace t, void *pdu)
	131	{
	132	size_t this_len;
	133
	134	if ((cur + 512) > cur_max)
c053af42 AB	135	if (!move_map()) {
c053af42 AB	136	cleanup_ifile();
d76c5b81	137	return 0;
c053af42	138	}
d76c5b81 AB	139
	140	next_t = cur_map + (cur - cur_min);
	141	this_len = convert_to_cpu(next_t, t, pdu);
	142	cur += this_len;
	143
	144	return 1;
	145	}
32ff7e3b AB	146
	147	double pct_done(void)
	148	{
	149	return 100.0 * ((double)cur / (double)total_size);
	150	}