assert(ddir_rw(ddir));
if (f->last_pos < f->real_file_size) {
- *b = (f->last_pos - f->file_offset) / td->o.min_bs[ddir];
+ unsigned long long pos;
+
+ if (f->last_pos == f->file_offset && td->o.ddir_seq_add < 0)
+ f->last_pos = f->real_file_size;
+
+ pos = f->last_pos - f->file_offset;
+ if (pos)
+ pos += td->o.ddir_seq_add;
+
+ *b = pos / td->o.min_bs[ddir];
return 0;
}
return __get_next_offset(td, io_u);
}
+static inline int io_u_fits(struct thread_data *td, struct io_u *io_u,
+ unsigned int buflen)
+{
+ struct fio_file *f = io_u->file;
+
+ return io_u->offset + buflen <= f->io_size + td->o.start_offset;
+}
+
static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u)
{
const int ddir = io_u->ddir;
unsigned int uninitialized_var(buflen);
unsigned int minbs, maxbs;
- long r, rand_max;
+ unsigned long r, rand_max;
assert(ddir_rw(ddir));
minbs = td->o.min_bs[ddir];
maxbs = td->o.max_bs[ddir];
+ if (minbs == maxbs)
+ return minbs;
+
if (td->o.use_os_rand)
rand_max = OS_RAND_MAX;
else
rand_max = FRAND_MAX;
- if (minbs == maxbs)
- buflen = minbs;
- else {
+ do {
if (td->o.use_os_rand)
r = os_random_long(&td->bsrange_state);
else
buflen = bsp->bs;
perc += bsp->perc;
- if (r <= ((rand_max / 100L) * perc))
+ if ((r <= ((rand_max / 100L) * perc)) &&
+ io_u_fits(td, io_u, buflen))
break;
}
}
+
if (!td->o.bs_unaligned && is_power_of_2(minbs))
buflen = (buflen + minbs - 1) & ~(minbs - 1);
- }
- if (io_u->offset + buflen > io_u->file->real_file_size) {
- dprint(FD_IO, "lower buflen %u -> %u (ddir=%d)\n", buflen,
- minbs, ddir);
- buflen = minbs;
- }
+ } while (!io_u_fits(td, io_u, buflen));
return buflen;
}
static inline enum fio_ddir get_rand_ddir(struct thread_data *td)
{
unsigned int v;
- long r;
+ unsigned long r;
if (td->o.use_os_rand) {
r = os_random_long(&td->rwmix_state);
} else
usec = td->rate_pending_usleep[ddir];
+ /*
+ * We are going to sleep, ensure that we flush anything pending as
+ * not to skew our latency numbers
+ */
+ if (td->cur_depth) {
+ int fio_unused ret;
+
+ ret = io_u_queued_complete(td, td->cur_depth, NULL);
+ }
+
fio_gettime(&t, NULL);
usec_sleep(td, usec);
usec = utime_since_now(&t);
do {
int opened = 0;
- long r;
+ unsigned long r;
if (td->o.use_os_rand) {
r = os_random_long(&td->next_file_state);
return 0;
}
+/*
+ * Fill offset and start time into the buffer content, to prevent too
+ * easy compressible data for simple de-dupe attempts. Do this for every
+ * 512b block in the range, since that should be the smallest block size
+ * we can expect from a device.
+ */
+static void small_content_scramble(struct io_u *io_u)
+{
+ unsigned int i, nr_blocks = io_u->buflen / 512;
+ unsigned long long boffset;
+ unsigned int offset;
+ void *p, *end;
+
+ if (!nr_blocks)
+ return;
+
+ p = io_u->xfer_buf;
+ boffset = io_u->offset;
+
+ for (i = 0; i < nr_blocks; i++) {
+ /*
+ * Fill the byte offset into a "random" start offset of
+ * the buffer, given by the product of the usec time
+ * and the actual offset.
+ */
+ offset = (io_u->start_time.tv_usec ^ boffset) & 511;
+ offset &= ~(sizeof(unsigned long long) - 1);
+ if (offset >= 512 - sizeof(unsigned long long))
+ offset -= sizeof(unsigned long long);
+ memcpy(p + offset, &boffset, sizeof(boffset));
+
+ end = p + 512 - sizeof(io_u->start_time);
+ memcpy(end, &io_u->start_time, sizeof(io_u->start_time));
+ p += 512;
+ boffset += 512;
+ }
+}
+
/*
* Return an io_u to be processed. Gets a buflen and offset, sets direction,
* etc. The returned io_u is fully ready to be prepped and submitted.
{
struct fio_file *f;
struct io_u *io_u;
+ int do_scramble = 0;
io_u = __get_io_u(td);
if (!io_u) {
f->last_start = io_u->offset;
f->last_pos = io_u->offset + io_u->buflen;
- if (td->o.verify != VERIFY_NONE && io_u->ddir == DDIR_WRITE)
- populate_verify_io_u(td, io_u);
- else if (td->o.refill_buffers && io_u->ddir == DDIR_WRITE)
- io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
- else if (io_u->ddir == DDIR_READ) {
+ if (io_u->ddir == DDIR_WRITE) {
+ if (td->o.verify != VERIFY_NONE)
+ populate_verify_io_u(td, io_u);
+ else if (td->o.refill_buffers)
+ io_u_fill_buffer(td, io_u, io_u->xfer_buflen);
+ else if (td->o.scramble_buffers)
+ do_scramble = 1;
+ } else if (io_u->ddir == DDIR_READ) {
/*
* Reset the buf_filled parameters so next time if the
* buffer is used for writes it is refilled.
if (!td_io_prep(td, io_u)) {
if (!td->o.disable_slat)
fio_gettime(&io_u->start_time, NULL);
+ if (do_scramble)
+ small_content_scramble(io_u);
return io_u;
}
err_put:
io_u->buf_filled_len = 0;
if (!td->o.zero_buffers)
- fill_random_buf(io_u->buf, max_bs);
+ fill_random_buf(&td->buf_state, io_u->buf, max_bs);
else
memset(io_u->buf, 0, max_bs);
}
projects / fio.git / blobdiff