*/
#include <stdio.h>
#include <stdlib.h>
+
#include "list.h"
#include "fio.h"
#include "blktrace_api.h"
-static int discard_pdu(int fd, struct blk_io_trace *t)
+#define TRACE_FIFO_SIZE 65536
+
+/*
+ * 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);
+
+ 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;
- if (lseek(fd, t->pdu_len, SEEK_CUR) < 0)
- return errno;
-
- return 0;
+ 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;
return 0;
}
-static void handle_trace(struct thread_data *td, struct blk_io_trace *t)
+/*
+ * 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_LIST_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;
+
+ list_add_tail(&ipo->list, &td->io_log_list);
}
+/*
+ * 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)
+{
+ int rw;
+
+ 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))
+ return;
+
+ 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);
+}
+
+/*
+ * 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];
+ unsigned int cpu;
+ unsigned int rw_bs[2];
+ struct fifo *fifo;
int fd;
fd = open(filename, O_RDONLY);
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;
do {
- int ret = read(fd, &t, sizeof(t));
+ int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));
- if (ret < 0) {
- td_verror(td, errno, "read blktrace file");
- return 1;
- } else if (!ret) {
+ if (ret < 0)
+ goto err;
+ else if (!ret)
+ break;
+ else if (ret < (int) sizeof(t)) {
+ log_err("fio: short fifo get\n");
break;
- } else if (ret != sizeof(t)) {
- log_err("fio: short read on blktrace file\n");
- return 1;
}
if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
- log_err("fio: bad magic in blktrace data\n");
- return 1;
+ 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);
- return 1;
+ goto err;
}
- ret = discard_pdu(fd, &t);
- if (ret) {
+ ret = discard_pdu(td, fifo, fd, &t);
+ if (ret < 0) {
td_verror(td, ret, "blktrace lseek");
- return 1;
+ goto err;
+ } else if (t.pdu_len != ret) {
+ log_err("fio: discarded %d of %d\n", ret, t.pdu_len);
+ goto err;
+ }
+ if (!ttime) {
+ ttime = t.time;
+ cpu = t.cpu;
}
- handle_trace(td, &t);
+ delay = 0;
+ if (cpu == t.cpu)
+ delay = t.time - ttime;
+ handle_trace(td, &t, delay, ios, rw_bs);
+ ttime = t.time;
+ cpu = t.cpu;
} while (1);
+ fifo_free(fifo);
close(fd);
+
+ 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;
}
projects / fio.git / blobdiff