blktrace: Initial checkin of ported version

Signed-off-by: San Mehat <san@google.com>
diff --git a/blkiomon.c b/blkiomon.c
new file mode 100644
index 0000000..9fc4d75
--- /dev/null
+++ b/blkiomon.c
@@ -0,0 +1,756 @@
+/*
+ * I/O monitor based on block queue trace data
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Author(s): Martin Peschke <mp3@de.ibm.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 <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <signal.h>
+#include <getopt.h>
+#include <errno.h>
+#include <locale.h>
+#include <libgen.h>
+#include <sys/msg.h>
+#include <pthread.h>
+#include <time.h>
+
+#include "blktrace.h"
+#include "rbtree.h"
+#include "jhash.h"
+#include "blkiomon.h"
+
+struct trace {
+	struct blk_io_trace bit;
+	struct rb_node node;
+	struct trace *next;
+	long sequence;
+};
+
+struct rb_search {
+	struct rb_node **node_ptr;
+	struct rb_node *parent;
+};
+
+struct dstat_msg {
+	long mtype;
+	struct blkiomon_stat stat;
+};
+
+struct dstat {
+	struct dstat_msg msg;
+	struct rb_node node;
+	struct dstat *next;
+};
+
+struct output {
+	char *fn;
+	FILE *fp;
+	char *buf;
+	int pipe;
+};
+
+static char blkiomon_version[] = "0.3";
+
+static FILE *ifp;
+static int interval = -1;
+
+static struct trace *vacant_traces_list = NULL;
+static int vacant_traces = 0;
+
+#define TRACE_HASH_SIZE 128
+struct trace *thash[TRACE_HASH_SIZE] = {};
+
+static struct dstat *vacant_dstats_list = NULL;
+static struct rb_root dstat_tree[2] = { RB_ROOT, RB_ROOT };
+static struct dstat *dstat_list[2] = {};
+static int dstat_curr = 0;
+
+static struct output drvdata, human, binary, debug;
+
+static char *msg_q_name = NULL;
+static int msg_q_id = -1, msg_q = -1;
+static long msg_id = -1;
+
+static pthread_t interval_thread;
+static pthread_mutex_t dstat_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+int data_is_native = -1;
+
+static int up = 1;
+
+/* debugging */
+static long leftover = 0, driverdata = 0, match = 0, mismatch = 0, sequence = 0;
+
+static void dump_bit(struct trace *t, const char *descr)
+{
+	struct blk_io_trace *bit = &t->bit;
+
+	if (!debug.fn)
+		return;
+
+	fprintf(debug.fp, "--- %s ---\n", descr);
+	fprintf(debug.fp, "magic    %16d\n", bit->magic);
+	fprintf(debug.fp, "sequence %16d\n", bit->sequence);
+	fprintf(debug.fp, "time     %16ld\n", (unsigned long)bit->time);
+	fprintf(debug.fp, "sector   %16ld\n", (unsigned long)bit->sector);
+	fprintf(debug.fp, "bytes    %16d\n", bit->bytes);
+	fprintf(debug.fp, "action   %16x\n", bit->action);
+	fprintf(debug.fp, "pid      %16d\n", bit->pid);
+	fprintf(debug.fp, "device   %16d\n", bit->device);
+	fprintf(debug.fp, "cpu      %16d\n", bit->cpu);
+	fprintf(debug.fp, "error    %16d\n", bit->error);
+	fprintf(debug.fp, "pdu_len  %16d\n", bit->pdu_len);
+
+	fprintf(debug.fp, "order    %16ld\n", t->sequence);
+}
+
+static void dump_bits(struct trace *t1, struct trace *t2, const char *descr)
+{
+	struct blk_io_trace *bit1 = &t1->bit;
+	struct blk_io_trace *bit2 = &t2->bit;
+
+	if (!debug.fn)
+		return;
+
+	fprintf(debug.fp, "--- %s ---\n", descr);
+	fprintf(debug.fp, "magic    %16d %16d\n", bit1->magic, bit2->magic);
+	fprintf(debug.fp, "sequence %16d %16d\n",
+		bit1->sequence, bit2->sequence);
+	fprintf(debug.fp, "time     %16ld %16ld\n",
+		(unsigned long)bit1->time, (unsigned long)bit2->time);
+	fprintf(debug.fp, "sector   %16ld %16ld\n",
+		(unsigned long)bit1->sector, (unsigned long)bit2->sector);
+	fprintf(debug.fp, "bytes    %16d %16d\n", bit1->bytes, bit2->bytes);
+	fprintf(debug.fp, "action   %16x %16x\n", bit1->action, bit2->action);
+	fprintf(debug.fp, "pid      %16d %16d\n", bit1->pid, bit2->pid);
+	fprintf(debug.fp, "device   %16d %16d\n", bit1->device, bit2->device);
+	fprintf(debug.fp, "cpu      %16d %16d\n", bit1->cpu, bit2->cpu);
+	fprintf(debug.fp, "error    %16d %16d\n", bit1->error, bit2->error);
+	fprintf(debug.fp, "pdu_len  %16d %16d\n", bit1->pdu_len, bit2->pdu_len);
+
+	fprintf(debug.fp, "order    %16ld %16ld\n", t1->sequence, t2->sequence);
+}
+
+static struct dstat *blkiomon_alloc_dstat(void)
+{
+	struct dstat *dstat;
+
+	if (vacant_dstats_list) {
+		dstat = vacant_dstats_list;
+		vacant_dstats_list = dstat->next;
+	} else
+		dstat = malloc(sizeof(*dstat));
+	if (!dstat) {
+		fprintf(stderr,
+			"blkiomon: could not allocate device statistic");
+		return NULL;
+	}
+
+	blkiomon_stat_init(&dstat->msg.stat);
+	return dstat;
+}
+
+static struct dstat *blkiomon_find_dstat(struct rb_search *search, __u32 device)
+{
+	struct rb_node **p = &(dstat_tree[dstat_curr].rb_node);
+	struct rb_node *parent = NULL;
+	struct dstat *dstat;
+
+	while (*p) {
+		parent = *p;
+
+		dstat = rb_entry(parent, struct dstat, node);
+
+		if (dstat->msg.stat.device < device)
+			p = &(*p)->rb_left;
+		else if (dstat->msg.stat.device > device)
+			p = &(*p)->rb_right;
+		else
+			return dstat;
+	}
+	search->node_ptr = p;
+	search->parent = parent;
+	return NULL;
+}
+
+static struct dstat *blkiomon_get_dstat(__u32 device)
+{
+	struct dstat *dstat;
+	struct rb_search search;
+
+	pthread_mutex_lock(&dstat_mutex);
+
+	dstat = blkiomon_find_dstat(&search, device);
+	if (dstat)
+		goto out;
+
+	dstat = blkiomon_alloc_dstat();
+	if (!dstat)
+		goto out;
+
+	dstat->msg.stat.device = device;
+
+	rb_link_node(&dstat->node, search.parent, search.node_ptr);
+	rb_insert_color(&dstat->node, &dstat_tree[dstat_curr]);
+
+	dstat->next = dstat_list[dstat_curr];
+	dstat_list[dstat_curr] = dstat;
+
+out:
+	pthread_mutex_unlock(&dstat_mutex);
+	return dstat;
+}
+
+static int blkiomon_output_msg_q(struct dstat *dstat)
+{
+	if (!msg_q_name)
+		return 0;
+
+	dstat->msg.mtype = msg_id;
+	return msgsnd(msg_q, &dstat->msg, sizeof(struct blkiomon_stat), 0);
+}
+
+static int blkiomon_output_binary(struct dstat *dstat)
+{
+	struct blkiomon_stat *p = &dstat->msg.stat;
+
+	if (!binary.fn)
+		return 0;
+
+	if (fwrite(p, sizeof(*p), 1, binary.fp) != 1)
+		goto failed;
+	if (binary.pipe && fflush(binary.fp))
+		goto failed;
+	return 0;
+
+failed:
+	fprintf(stderr, "blkiomon: could not write to %s\n", binary.fn);
+	fclose(binary.fp);
+	binary.fn = NULL;
+	return 1;
+}
+
+static struct dstat *blkiomon_output(struct dstat *head, struct timespec *ts)
+{
+	struct dstat *dstat, *tail = NULL;
+
+	for (dstat = head; dstat; dstat = dstat->next) {
+		dstat->msg.stat.time = ts->tv_sec;
+		blkiomon_stat_print(human.fp, &dstat->msg.stat);
+		blkiomon_stat_to_be(&dstat->msg.stat);
+		blkiomon_output_binary(dstat);
+		blkiomon_output_msg_q(dstat);
+		tail = dstat;
+	}
+	return tail;
+}
+
+static void *blkiomon_interval(void *data)
+{
+	struct timespec wake, r;
+	struct dstat *head, *tail;
+	int finished;
+
+	clock_gettime(CLOCK_REALTIME, &wake);
+
+	while (1) {
+		wake.tv_sec += interval;
+		if (clock_nanosleep(CLOCK_REALTIME, TIMER_ABSTIME, &wake, &r)) {
+			fprintf(stderr, "blkiomon: interrupted sleep");
+			continue;
+		}
+
+		/* grab tree and make data gatherer build up another tree */
+		pthread_mutex_lock(&dstat_mutex);
+		finished = dstat_curr;
+		dstat_curr = dstat_curr ? 0 : 1;
+		pthread_mutex_unlock(&dstat_mutex);
+
+		head = dstat_list[finished];
+		if (!head)
+			continue;
+		dstat_list[finished] = NULL;
+		dstat_tree[finished] = RB_ROOT;
+		tail = blkiomon_output(head, &wake);
+
+		pthread_mutex_lock(&dstat_mutex);
+		tail->next = vacant_dstats_list;
+		vacant_dstats_list = head;
+		pthread_mutex_unlock(&dstat_mutex);
+	}
+	return data;
+}
+
+#define BLK_DATADIR(a) (((a) >> BLK_TC_SHIFT) & (BLK_TC_READ | BLK_TC_WRITE))
+
+static int blkiomon_account(struct blk_io_trace *bit_d,
+			    struct blk_io_trace *bit_c)
+{
+	struct dstat *dstat;
+	struct blkiomon_stat *p;
+	__u64 d2c = (bit_c->time - bit_d->time) / 1000; /* ns -> us */
+	__u32 size = bit_d->bytes;
+	__u64 thrput = size * 1000 / d2c;
+
+	dstat = blkiomon_get_dstat(bit_d->device);
+	if (!dstat)
+		return 1;
+	p = &dstat->msg.stat;
+
+	if (BLK_DATADIR(bit_c->action) & BLK_TC_READ) {
+		minmax_account(&p->thrput_r, thrput);
+		minmax_account(&p->size_r, size);
+		minmax_account(&p->d2c_r, d2c);
+	} else if (BLK_DATADIR(bit_c->action) & BLK_TC_WRITE) {
+		minmax_account(&p->thrput_w, thrput);
+		minmax_account(&p->size_w, size);
+		minmax_account(&p->d2c_w, d2c);
+	} else
+		p->bidir++;
+
+	histlog2_account(p->size_hist, size, &size_hist);
+	histlog2_account(p->d2c_hist, d2c, &d2c_hist);
+	return 0;
+}
+
+static struct trace *blkiomon_alloc_trace(void)
+{
+	struct trace *t = vacant_traces_list;
+	if (t) {
+		vacant_traces_list = t->next;
+		vacant_traces--;
+	} else
+		t = malloc(sizeof(*t));
+	memset(t, 0, sizeof(*t));
+	return t;
+}
+
+static void blkiomon_free_trace(struct trace *t)
+{
+	if (vacant_traces < 256) {
+		t->next = vacant_traces_list;
+		vacant_traces_list = t;
+		vacant_traces++;
+	} else
+		free(t);
+}
+
+static int action(int a)
+{
+	int bits = BLK_TC_WRITE | BLK_TC_READ | BLK_TC_FS | BLK_TC_PC;
+	return a & (BLK_TC_ACT(bits));
+}
+
+static void blkiomon_store_trace(struct trace *t)
+{
+	int i = t->bit.sector % TRACE_HASH_SIZE;
+
+	t->next = thash[i];
+	thash[i] = t;
+}
+
+static struct trace *blkiomon_fetch_trace(struct blk_io_trace *bit)
+{
+	int i = bit->sector % TRACE_HASH_SIZE;
+	struct trace *t, *prev = NULL;
+
+	for (t = thash[i]; t; t = t->next) {
+		if (t->bit.device == bit->device &&
+		    t->bit.sector == bit->sector &&
+		    action(t->bit.action) == action(bit->action)) {
+			if (prev)
+				prev->next = t->next;
+			else
+				thash[i] = t->next;
+			return t;
+		}
+		prev = t;
+	}
+	return NULL;
+}
+
+static struct trace *blkiomon_do_trace(struct trace *t)
+{
+	struct trace *t_stored, *t_old, *t_young;
+
+	/* store trace if there is no match yet */
+	t_stored = blkiomon_fetch_trace(&t->bit);
+	if (!t_stored) {
+		blkiomon_store_trace(t);
+		return blkiomon_alloc_trace();
+	}
+
+	/* figure out older trace and younger trace */
+	if (t_stored->bit.time < t->bit.time) {
+		t_old = t_stored;
+		t_young = t;
+	} else {
+		t_old = t;
+		t_young = t_stored;
+	}
+
+	/* we need an older D trace and a younger C trace */
+	if (t_old->bit.action & BLK_TC_ACT(BLK_TC_ISSUE) &&
+	    t_young->bit.action & BLK_TC_ACT(BLK_TC_COMPLETE)) {
+		/* matching D and C traces - update statistics */
+		match++;
+		blkiomon_account(&t_old->bit, &t_young->bit);
+		blkiomon_free_trace(t_stored);
+		return t;
+	}
+
+	/* no matching D and C traces - keep more recent trace */
+	dump_bits(t_old, t_young, "mismatch");
+	mismatch++;
+	blkiomon_store_trace(t_young);
+	return t_old;
+}
+
+static int blkiomon_dump_drvdata(struct blk_io_trace *bit, void *pdu_buf)
+{
+	if (!drvdata.fn)
+		return 0;
+
+	if (fwrite(bit, sizeof(*bit), 1, drvdata.fp) != 1)
+		goto failed;
+	if (fwrite(pdu_buf, bit->pdu_len, 1, drvdata.fp) != 1)
+		goto failed;
+	if (drvdata.pipe && fflush(drvdata.fp))
+		goto failed;
+	return 0;
+
+failed:
+	fprintf(stderr, "blkiomon: could not write to %s\n", drvdata.fn);
+	fclose(drvdata.fp);
+	drvdata.fn = NULL;
+	return 1;
+}
+
+static int blkiomon_do_fifo(void)
+{
+	struct trace *t;
+	struct blk_io_trace *bit;
+	void *pdu_buf = NULL;
+
+	t = blkiomon_alloc_trace();
+	if (!t)
+		return 1;
+	bit = &t->bit;
+
+	while (up) {
+		if (fread(bit, sizeof(*bit), 1, ifp) != 1) {
+			if (!feof(ifp))
+				fprintf(stderr,
+					"blkiomon: could not read trace");
+			break;
+		}
+		if (ferror(ifp)) {
+			clearerr(ifp);
+			fprintf(stderr, "blkiomon: error while reading trace");
+			break;
+		}
+
+		if (data_is_native == -1 && check_data_endianness(bit->magic)) {
+			fprintf(stderr, "blkiomon: endianess problem\n");
+			break;
+		}
+
+		/* endianess */
+		trace_to_cpu(bit);
+		if (verify_trace(bit)) {
+			fprintf(stderr, "blkiomon: bad trace\n");
+			break;
+		}
+
+		/* read additional trace payload */
+		if (bit->pdu_len) {
+			pdu_buf = realloc(pdu_buf, bit->pdu_len);
+			if (fread(pdu_buf, bit->pdu_len, 1, ifp) != 1) {
+				clearerr(ifp);
+				fprintf(stderr, "blkiomon: could not read payload\n");
+				break;
+			}
+		}
+
+		t->sequence = sequence++;
+
+		/* forward low-level device driver trace to other tool */
+		if (bit->action & BLK_TC_ACT(BLK_TC_DRV_DATA)) {
+			driverdata++;
+			if (blkiomon_dump_drvdata(bit, pdu_buf)) {
+				fprintf(stderr, "blkiomon: could not send trace\n");
+				break;
+			}
+			continue;
+		}
+
+		if (!(bit->action & BLK_TC_ACT(BLK_TC_ISSUE | BLK_TC_COMPLETE)))
+			continue;
+
+		/* try to find matching trace and update statistics */
+		t = blkiomon_do_trace(t);
+		if (!t) {
+			fprintf(stderr, "blkiomon: could not alloc trace\n");
+			break;
+		}
+		bit = &t->bit;
+		/* t and bit will be recycled for next incoming trace */
+	}
+	blkiomon_free_trace(t);
+	free(pdu_buf);
+	return 0;
+}
+
+static int blkiomon_open_output(struct output *out)
+{
+	int mode, vbuf_size;
+
+	if (!out->fn)
+		return 0;
+
+	if (!strcmp(out->fn, "-")) {
+		out->fp = fdopen(STDOUT_FILENO, "w");
+		mode = _IOLBF;
+		vbuf_size = 4096;
+		out->pipe = 1;
+	} else {
+		out->fp = fopen(out->fn, "w");
+		mode = _IOFBF;
+		vbuf_size = 128 * 1024;
+		out->pipe = 0;
+	}
+	if (!out->fp)
+		goto failed;
+	out->buf = malloc(128 * 1024);
+	if (setvbuf(out->fp, out->buf, mode, vbuf_size))
+		goto failed;
+	return 0;
+
+failed:
+	fprintf(stderr, "blkiomon: could not write to %s\n", out->fn);
+	out->fn = NULL;
+	free(out->buf);
+	return 1;
+}
+
+static int blkiomon_open_msg_q(void)
+{
+	key_t key;
+
+	if (!msg_q_name)
+		return 0;
+	if (!msg_q_id || msg_id <= 0)
+		return 1;
+	key = ftok(msg_q_name, msg_q_id);
+	if (key == -1)
+		return 1;
+	while (up) {
+		msg_q = msgget(key, S_IRWXU);
+		if (msg_q >= 0)
+			break;
+	}
+	return (msg_q >= 0 ? 0 : -1);
+}
+
+static void blkiomon_debug(void)
+{
+	int i;
+	struct trace *t;
+
+	if (!debug.fn)
+		return;
+
+	for (i = 0; i < TRACE_HASH_SIZE; i++)
+		for (t = thash[i]; t; t = t->next) {
+			dump_bit(t, "leftover");
+			leftover++;
+		}
+
+	fprintf(debug.fp, "%ld leftover, %ld match, %ld mismatch, "
+		"%ld driverdata, %ld overall\n",
+		leftover, match, mismatch, driverdata, sequence);
+}
+
+#define S_OPTS "b:d:D:h:I:Q:q:m:V"
+
+static char usage_str[] = "\n\nblkiomon " \
+	"-I <interval>       | --interval=<interval>\n" \
+	"[ -h <file>         | --human-readable=<file> ]\n" \
+	"[ -b <file>         | --binary=<file> ]\n" \
+	"[ -D <file>         | --debug=<file> ]\n" \
+	"[ -Q <path name>    | --msg-queue=<path name>]\n" \
+	"[ -q <msg queue id> | --msg-queue-id=<msg queue id>]\n" \
+	"[ -m <msg id>       | --msg-id=<msg id>]\n" \
+	"[ -V                | --version ]\n\n" \
+	"\t-I   Sample interval.\n" \
+	"\t-h   Human-readable output file.\n" \
+	"\t-b   Binary output file.\n" \
+	"\t-d   Output file for data emitted by low level device driver.\n" \
+	"\t-D   Output file for debugging data.\n" \
+	"\t-Qqm Output to message queue using given ID for messages.\n" \
+	"\t-V   Print program version.\n\n";
+
+static struct option l_opts[] = {
+	{
+		.name = "human-readable",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'h'
+	},
+	{
+		.name = "binary",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'b'
+	},
+	{
+		.name = "dump-lldd",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'd'
+	},
+	{
+		.name = "debug",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'D'
+	},
+	{
+		.name = "interval",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'I'
+	},
+	{
+		.name = "msg-queue",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'Q'
+	},
+	{
+		.name = "msg-queue-id",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'q'
+	},
+	{
+		.name = "msg-id",
+		.has_arg = required_argument,
+		.flag = NULL,
+		.val = 'm'
+	},
+	{
+		.name = "version",
+		.has_arg = no_argument,
+		.flag = NULL,
+		.val = 'V'
+	},
+	{
+		.name = NULL,
+	}
+};
+
+static void blkiomon_signal(int signal)
+{
+	fprintf(stderr, "blkiomon: terminated by signal\n");
+	up = signal & 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int c;
+
+	signal(SIGALRM, blkiomon_signal);
+	signal(SIGINT, blkiomon_signal);
+	signal(SIGTERM, blkiomon_signal);
+	signal(SIGQUIT, blkiomon_signal);
+
+	while ((c = getopt_long(argc, argv, S_OPTS, l_opts, NULL)) != -1) {
+		switch (c) {
+		case 'h':
+			human.fn = optarg;
+			break;
+		case 'b':
+			binary.fn = optarg;
+			break;
+		case 'd':
+			drvdata.fn = optarg;
+			break;
+		case 'D':
+			debug.fn = optarg;
+			break;
+		case 'I':
+			interval = atoi(optarg);
+			break;
+		case 'Q':
+			msg_q_name = optarg;
+			break;
+		case 'q':
+			msg_q_id = atoi(optarg);
+			break;
+		case 'm':
+			msg_id = atoi(optarg);
+			break;
+		case 'V':
+			printf("%s version %s\n", argv[0], blkiomon_version);
+			return 0;
+		default:
+			fprintf(stderr, "Usage: %s", usage_str);
+			return 1;
+		}
+	}
+
+	if (interval <= 0) {
+		fprintf(stderr, "Usage: %s", usage_str);
+		return 1;
+	}
+
+	ifp = fdopen(STDIN_FILENO, "r");
+	if (!ifp) {
+		perror("blkiomon: could not open stdin for reading");
+		return 1;
+	}
+
+	if (blkiomon_open_output(&human))
+		return 1;
+	if (blkiomon_open_output(&binary))
+		return 1;
+	if (blkiomon_open_output(&drvdata))
+		return 1;
+	if (blkiomon_open_output(&debug))
+		return 1;
+	if (blkiomon_open_msg_q())
+		return 1;
+
+	if (pthread_create(&interval_thread, NULL, blkiomon_interval, NULL)) {
+		fprintf(stderr, "blkiomon: could not create thread");
+		return 1;
+	}
+
+	blkiomon_do_fifo();
+
+	blkiomon_debug();
+	return 0;
+}