#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <assert.h>
#include "fio.h"
#include "hash.h"
#include "verify.h"
#include "trim.h"
#include "lib/rand.h"
#include "lib/axmap.h"
#include "err.h"
struct io_completion_data {
int nr; /* input */
int error; /* output */
uint64_t bytes_done[DDIR_RWDIR_CNT]; /* output */
struct timeval time; /* output */
};
/*
* The ->io_axmap contains a map of blocks we have or have not done io
* to yet. Used to make sure we cover the entire range in a fair fashion.
*/
static int random_map_free(struct fio_file *f, const uint64_t block)
{
return !axmap_isset(f->io_axmap, block);
}
/*
* Mark a given offset as used in the map.
*/
static void mark_random_map(struct thread_data *td, struct io_u *io_u)
{
unsigned int min_bs = td->o.rw_min_bs;
struct fio_file *f = io_u->file;
unsigned int nr_blocks;
uint64_t block;
block = (io_u->offset - f->file_offset) / (uint64_t) min_bs;
nr_blocks = (io_u->buflen + min_bs - 1) / min_bs;
if (!(io_u->flags & IO_U_F_BUSY_OK))
nr_blocks = axmap_set_nr(f->io_axmap, block, nr_blocks);
if ((nr_blocks * min_bs) < io_u->buflen)
io_u->buflen = nr_blocks * min_bs;
}
static uint64_t last_block(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir)
{
uint64_t max_blocks;
uint64_t max_size;
assert(ddir_rw(ddir));
/*
* Hmm, should we make sure that ->io_size <= ->real_file_size?
*/
max_size = f->io_size;
if (max_size > f->real_file_size)
max_size = f->real_file_size;
if (td->o.zone_range)
max_size = td->o.zone_range;
if (td->o.min_bs[ddir] > td->o.ba[ddir])
max_size -= td->o.min_bs[ddir] - td->o.ba[ddir];
max_blocks = max_size / (uint64_t) td->o.ba[ddir];
if (!max_blocks)
return 0;
return max_blocks;
}
struct rand_off {
struct flist_head list;
uint64_t off;
};
static int __get_next_rand_offset(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir, uint64_t *b)
{
uint64_t r;
if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE) {
uint64_t lastb;
lastb = last_block(td, f, ddir);
if (!lastb)
return 1;
r = __rand(&td->random_state);
dprint(FD_RANDOM, "off rand %llu\n", (unsigned long long) r);
*b = lastb * (r / ((uint64_t) FRAND_MAX + 1.0));
} else {
uint64_t off = 0;
assert(fio_file_lfsr(f));
if (lfsr_next(&f->lfsr, &off))
return 1;
*b = off;
}
/*
* if we are not maintaining a random map, we are done.
*/
if (!file_randommap(td, f))
goto ret;
/*
* calculate map offset and check if it's free
*/
if (random_map_free(f, *b))
goto ret;
dprint(FD_RANDOM, "get_next_rand_offset: offset %llu busy\n",
(unsigned long long) *b);
*b = axmap_next_free(f->io_axmap, *b);
if (*b == (uint64_t) -1ULL)
return 1;
ret:
return 0;
}
static int __get_next_rand_offset_zipf(struct thread_data *td,
struct fio_file *f, enum fio_ddir ddir,
uint64_t *b)
{
*b = zipf_next(&f->zipf);
return 0;
}
static int __get_next_rand_offset_pareto(struct thread_data *td,
struct fio_file *f, enum fio_ddir ddir,
uint64_t *b)
{
*b = pareto_next(&f->zipf);
return 0;
}
static int flist_cmp(void *data, struct flist_head *a, struct flist_head *b)
{
struct rand_off *r1 = flist_entry(a, struct rand_off, list);
struct rand_off *r2 = flist_entry(b, struct rand_off, list);
return r1->off - r2->off;
}
static int get_off_from_method(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir, uint64_t *b)
{
if (td->o.random_distribution == FIO_RAND_DIST_RANDOM)
return __get_next_rand_offset(td, f, ddir, b);
else if (td->o.random_distribution == FIO_RAND_DIST_ZIPF)
return __get_next_rand_offset_zipf(td, f, ddir, b);
else if (td->o.random_distribution == FIO_RAND_DIST_PARETO)
return __get_next_rand_offset_pareto(td, f, ddir, b);
log_err("fio: unknown random distribution: %d\n", td->o.random_distribution);
return 1;
}
/*
* Sort the reads for a verify phase in batches of verifysort_nr, if
* specified.
*/
static inline int should_sort_io(struct thread_data *td)
{
if (!td->o.verifysort_nr || !td->o.do_verify)
return 0;
if (!td_random(td))
return 0;
if (td->runstate != TD_VERIFYING)
return 0;
if (td->o.random_generator == FIO_RAND_GEN_TAUSWORTHE)
return 0;
return 1;
}
static int should_do_random(struct thread_data *td, enum fio_ddir ddir)
{
unsigned int v;
unsigned long r;
if (td->o.perc_rand[ddir] == 100)
return 1;
r = __rand(&td->seq_rand_state[ddir]);
v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
return v <= td->o.perc_rand[ddir];
}
static int get_next_rand_offset(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir, uint64_t *b)
{
struct rand_off *r;
int i, ret = 1;
if (!should_sort_io(td))
return get_off_from_method(td, f, ddir, b);
if (!flist_empty(&td->next_rand_list)) {
fetch:
r = flist_first_entry(&td->next_rand_list, struct rand_off, list);
flist_del(&r->list);
*b = r->off;
free(r);
return 0;
}
for (i = 0; i < td->o.verifysort_nr; i++) {
r = malloc(sizeof(*r));
ret = get_off_from_method(td, f, ddir, &r->off);
if (ret) {
free(r);
break;
}
flist_add(&r->list, &td->next_rand_list);
}
if (ret && !i)
return ret;
assert(!flist_empty(&td->next_rand_list));
flist_sort(NULL, &td->next_rand_list, flist_cmp);
goto fetch;
}
static int get_next_rand_block(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir, uint64_t *b)
{
if (!get_next_rand_offset(td, f, ddir, b))
return 0;
if (td->o.time_based) {
fio_file_reset(td, f);
if (!get_next_rand_offset(td, f, ddir, b))
return 0;
}
dprint(FD_IO, "%s: rand offset failed, last=%llu, size=%llu\n",
f->file_name, (unsigned long long) f->last_pos[ddir],
(unsigned long long) f->real_file_size);
return 1;
}
static int get_next_seq_offset(struct thread_data *td, struct fio_file *f,
enum fio_ddir ddir, uint64_t *offset)
{
struct thread_options *o = &td->o;
assert(ddir_rw(ddir));
if (f->last_pos[ddir] >= f->io_size + get_start_offset(td, f) &&
o->time_based)
f->last_pos[ddir] = f->last_pos[ddir] - f->io_size;
if (f->last_pos[ddir] < f->real_file_size) {
uint64_t pos;
if (f->last_pos[ddir] == f->file_offset && o->ddir_seq_add < 0)
f->last_pos[ddir] = f->real_file_size;
pos = f->last_pos[ddir] - f->file_offset;
if (pos && o->ddir_seq_add) {
pos += o->ddir_seq_add;
/*
* If we reach beyond the end of the file
* with holed IO, wrap around to the
* beginning again.
*/
if (pos >= f->real_file_size)
pos = f->file_offset;
}
*offset = pos;
return 0;
}
return 1;
}
static int get_next_block(struct thread_data *td, struct io_u *io_u,
enum fio_ddir ddir, int rw_seq,
unsigned int *is_random)
{
struct fio_file *f = io_u->file;
uint64_t b, offset;
int ret;
assert(ddir_rw(ddir));
b = offset = -1ULL;
if (rw_seq) {
if (td_random(td)) {
if (should_do_random(td, ddir)) {
ret = get_next_rand_block(td, f, ddir, &b);
*is_random = 1;
} else {
*is_random = 0;
io_u->flags |= IO_U_F_BUSY_OK;
ret = get_next_seq_offset(td, f, ddir, &offset);
if (ret)
ret = get_next_rand_block(td, f, ddir, &b);
}
} else {
*is_random = 0;
ret = get_next_seq_offset(td, f, ddir, &offset);
}
} else {
io_u->flags |= IO_U_F_BUSY_OK;
*is_random = 0;
if (td->o.rw_seq == RW_SEQ_SEQ) {
ret = get_next_seq_offset(td, f, ddir, &offset);
if (ret) {
ret = get_next_rand_block(td, f, ddir, &b);
*is_random = 0;
}
} else if (td->o.rw_seq == RW_SEQ_IDENT) {
if (f->last_start[ddir] != -1ULL)
offset = f->last_start[ddir] - f->file_offset;
else
offset = 0;
ret = 0;
} else {
log_err("fio: unknown rw_seq=%d\n", td->o.rw_seq);
ret = 1;
}
}
if (!ret) {
if (offset != -1ULL)
io_u->offset = offset;
else if (b != -1ULL)
io_u->offset = b * td->o.ba[ddir];
else {
log_err("fio: bug in offset generation: offset=%llu, b=%llu\n", (unsigned long long) offset, (unsigned long long) b);
ret = 1;
}
}
return ret;
}
/*
* For random io, generate a random new block and see if it's used. Repeat
* until we find a free one. For sequential io, just return the end of
* the last io issued.
*/
static int __get_next_offset(struct thread_data *td, struct io_u *io_u,
unsigned int *is_random)
{
struct fio_file *f = io_u->file;
enum fio_ddir ddir = io_u->ddir;
int rw_seq_hit = 0;
assert(ddir_rw(ddir));
if (td->o.ddir_seq_nr && !--td->ddir_seq_nr) {
rw_seq_hit = 1;
td->ddir_seq_nr = td->o.ddir_seq_nr;
}
if (get_next_block(td, io_u, ddir, rw_seq_hit, is_random))
return 1;
if (io_u->offset >= f->io_size) {
dprint(FD_IO, "get_next_offset: offset %llu >= io_size %llu\n",
(unsigned long long) io_u->offset,
(unsigned long long) f->io_size);
return 1;
}
io_u->offset += f->file_offset;
if (io_u->offset >= f->real_file_size) {
dprint(FD_IO, "get_next_offset: offset %llu >= size %llu\n",
(unsigned long long) io_u->offset,
(unsigned long long) f->real_file_size);
return 1;
}
return 0;
}
static int get_next_offset(struct thread_data *td, struct io_u *io_u,
unsigned int *is_random)
{
if (td->flags & TD_F_PROFILE_OPS) {
struct prof_io_ops *ops = &td->prof_io_ops;
if (ops->fill_io_u_off)
return ops->fill_io_u_off(td, io_u, is_random);
}
return __get_next_offset(td, io_u, is_random);
}
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 + get_start_offset(td, f);
}
static unsigned int __get_next_buflen(struct thread_data *td, struct io_u *io_u,
unsigned int is_random)
{
int ddir = io_u->ddir;
unsigned int buflen = 0;
unsigned int minbs, maxbs;
unsigned long r;
assert(ddir_rw(ddir));
if (td->o.bs_is_seq_rand)
ddir = is_random ? DDIR_WRITE: DDIR_READ;
minbs = td->o.min_bs[ddir];
maxbs = td->o.max_bs[ddir];
if (minbs == maxbs)
return minbs;
/*
* If we can't satisfy the min block size from here, then fail
*/
if (!io_u_fits(td, io_u, minbs))
return 0;
do {
r = __rand(&td->bsrange_state);
if (!td->o.bssplit_nr[ddir]) {
buflen = 1 + (unsigned int) ((double) maxbs *
(r / (FRAND_MAX + 1.0)));
if (buflen < minbs)
buflen = minbs;
} else {
long perc = 0;
unsigned int i;
for (i = 0; i < td->o.bssplit_nr[ddir]; i++) {
struct bssplit *bsp = &td->o.bssplit[ddir][i];
buflen = bsp->bs;
perc += bsp->perc;
if ((r <= ((FRAND_MAX / 100L) * perc)) &&
io_u_fits(td, io_u, buflen))
break;
}
}
if (td->o.do_verify && td->o.verify != VERIFY_NONE)
buflen = (buflen + td->o.verify_interval - 1) &
~(td->o.verify_interval - 1);
if (!td->o.bs_unaligned && is_power_of_2(minbs))
buflen = (buflen + minbs - 1) & ~(minbs - 1);
} while (!io_u_fits(td, io_u, buflen));
return buflen;
}
static unsigned int get_next_buflen(struct thread_data *td, struct io_u *io_u,
unsigned int is_random)
{
if (td->flags & TD_F_PROFILE_OPS) {
struct prof_io_ops *ops = &td->prof_io_ops;
if (ops->fill_io_u_size)
return ops->fill_io_u_size(td, io_u, is_random);
}
return __get_next_buflen(td, io_u, is_random);
}
static void set_rwmix_bytes(struct thread_data *td)
{
unsigned int diff;
/*
* we do time or byte based switch. this is needed because
* buffered writes may issue a lot quicker than they complete,
* whereas reads do not.
*/
diff = td->o.rwmix[td->rwmix_ddir ^ 1];
td->rwmix_issues = (td->io_issues[td->rwmix_ddir] * diff) / 100;
}
static inline enum fio_ddir get_rand_ddir(struct thread_data *td)
{
unsigned int v;
unsigned long r;
r = __rand(&td->rwmix_state);
v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
if (v <= td->o.rwmix[DDIR_READ])
return DDIR_READ;
return DDIR_WRITE;
}
void io_u_quiesce(struct thread_data *td)
{
/*
* We are going to sleep, ensure that we flush anything pending as
* not to skew our latency numbers.
*
* Changed to only monitor 'in flight' requests here instead of the
* td->cur_depth, b/c td->cur_depth does not accurately represent
* io's that have been actually submitted to an async engine,
* and cur_depth is meaningless for sync engines.
*/
if (td->io_u_queued || td->cur_depth) {
int fio_unused ret;
ret = td_io_commit(td);
}
while (td->io_u_in_flight) {
int fio_unused ret;
ret = io_u_queued_complete(td, 1, NULL);
}
}
static enum fio_ddir rate_ddir(struct thread_data *td, enum fio_ddir ddir)
{
enum fio_ddir odir = ddir ^ 1;
long usec;
assert(ddir_rw(ddir));
if (td->rate_pending_usleep[ddir] <= 0)
return ddir;
/*
* We have too much pending sleep in this direction. See if we
* should switch.
*/
if (td_rw(td) && td->o.rwmix[odir]) {
/*
* Other direction does not have too much pending, switch
*/
if (td->rate_pending_usleep[odir] < 100000)
return odir;
/*
* Both directions have pending sleep. Sleep the minimum time
* and deduct from both.
*/
if (td->rate_pending_usleep[ddir] <=
td->rate_pending_usleep[odir]) {
usec = td->rate_pending_usleep[ddir];
} else {
usec = td->rate_pending_usleep[odir];
ddir = odir;
}
} else
usec = td->rate_pending_usleep[ddir];
io_u_quiesce(td);
usec = usec_sleep(td, usec);
td->rate_pending_usleep[ddir] -= usec;
odir = ddir ^ 1;
if (td_rw(td) && __should_check_rate(td, odir))
td->rate_pending_usleep[odir] -= usec;
if (ddir == DDIR_TRIM)
return DDIR_TRIM;
return ddir;
}
/*
* Return the data direction for the next io_u. If the job is a
* mixed read/write workload, check the rwmix cycle and switch if
* necessary.
*/
static enum fio_ddir get_rw_ddir(struct thread_data *td)
{
enum fio_ddir ddir;
/*
* see if it's time to fsync
*/
if (td->o.fsync_blocks &&
!(td->io_issues[DDIR_WRITE] % td->o.fsync_blocks) &&
td->io_issues[DDIR_WRITE] && should_fsync(td))
return DDIR_SYNC;
/*
* see if it's time to fdatasync
*/
if (td->o.fdatasync_blocks &&
!(td->io_issues[DDIR_WRITE] % td->o.fdatasync_blocks) &&
td->io_issues[DDIR_WRITE] && should_fsync(td))
return DDIR_DATASYNC;
/*
* see if it's time to sync_file_range
*/
if (td->sync_file_range_nr &&
!(td->io_issues[DDIR_WRITE] % td->sync_file_range_nr) &&
td->io_issues[DDIR_WRITE] && should_fsync(td))
return DDIR_SYNC_FILE_RANGE;
if (td_rw(td)) {
/*
* Check if it's time to seed a new data direction.
*/
if (td->io_issues[td->rwmix_ddir] >= td->rwmix_issues) {
/*
* Put a top limit on how many bytes we do for
* one data direction, to avoid overflowing the
* ranges too much
*/
ddir = get_rand_ddir(td);
if (ddir != td->rwmix_ddir)
set_rwmix_bytes(td);
td->rwmix_ddir = ddir;
}
ddir = td->rwmix_ddir;
} else if (td_read(td))
ddir = DDIR_READ;
else if (td_write(td))
ddir = DDIR_WRITE;
else
ddir = DDIR_TRIM;
td->rwmix_ddir = rate_ddir(td, ddir);
return td->rwmix_ddir;
}
static void set_rw_ddir(struct thread_data *td, struct io_u *io_u)
{
io_u->ddir = io_u->acct_ddir = get_rw_ddir(td);
if (io_u->ddir == DDIR_WRITE && (td->io_ops->flags & FIO_BARRIER) &&
td->o.barrier_blocks &&
!(td->io_issues[DDIR_WRITE] % td->o.barrier_blocks) &&
td->io_issues[DDIR_WRITE])
io_u->flags |= IO_U_F_BARRIER;
}
void put_file_log(struct thread_data *td, struct fio_file *f)
{
unsigned int ret = put_file(td, f);
if (ret)
td_verror(td, ret, "file close");
}
void put_io_u(struct thread_data *td, struct io_u *io_u)
{
td_io_u_lock(td);
if (io_u->file && !(io_u->flags & IO_U_F_NO_FILE_PUT))
put_file_log(td, io_u->file);
io_u->file = NULL;
io_u->flags |= IO_U_F_FREE;
if (io_u->flags & IO_U_F_IN_CUR_DEPTH)
td->cur_depth--;
io_u_qpush(&td->io_u_freelist, io_u);
td_io_u_unlock(td);
td_io_u_free_notify(td);
}
void clear_io_u(struct thread_data *td, struct io_u *io_u)
{
io_u->flags &= ~IO_U_F_FLIGHT;
put_io_u(td, io_u);
}
void requeue_io_u(struct thread_data *td, struct io_u **io_u)
{
struct io_u *__io_u = *io_u;
enum fio_ddir ddir = acct_ddir(__io_u);
dprint(FD_IO, "requeue %p\n", __io_u);
td_io_u_lock(td);
__io_u->flags |= IO_U_F_FREE;
if ((__io_u->flags & IO_U_F_FLIGHT) && ddir_rw(ddir))
td->io_issues[ddir]--;
__io_u->flags &= ~IO_U_F_FLIGHT;
if (__io_u->flags & IO_U_F_IN_CUR_DEPTH)
td->cur_depth--;
io_u_rpush(&td->io_u_requeues, __io_u);
td_io_u_unlock(td);
*io_u = NULL;
}
static int fill_io_u(struct thread_data *td, struct io_u *io_u)
{
unsigned int is_random;
if (td->io_ops->flags & FIO_NOIO)
goto out;
set_rw_ddir(td, io_u);
/*
* fsync() or fdatasync() or trim etc, we are done
*/
if (!ddir_rw(io_u->ddir))
goto out;
/*
* See if it's time to switch to a new zone
*/
if (td->zone_bytes >= td->o.zone_size && td->o.zone_skip) {
struct fio_file *f = io_u->file;
td->zone_bytes = 0;
f->file_offset += td->o.zone_range + td->o.zone_skip;
/*
* Wrap from the beginning, if we exceed the file size
*/
if (f->file_offset >= f->real_file_size)
f->file_offset = f->real_file_size - f->file_offset;
f->last_pos[io_u->ddir] = f->file_offset;
td->io_skip_bytes += td->o.zone_skip;
}
/*
* No log, let the seq/rand engine retrieve the next buflen and
* position.
*/
if (get_next_offset(td, io_u, &is_random)) {
dprint(FD_IO, "io_u %p, failed getting offset\n", io_u);
return 1;
}
io_u->buflen = get_next_buflen(td, io_u, is_random);
if (!io_u->buflen) {
dprint(FD_IO, "io_u %p, failed getting buflen\n", io_u);
return 1;
}
if (io_u->offset + io_u->buflen > io_u->file->real_file_size) {
dprint(FD_IO, "io_u %p, offset too large\n", io_u);
dprint(FD_IO, " off=%llu/%lu > %llu\n",
(unsigned long long) io_u->offset, io_u->buflen,
(unsigned long long) io_u->file->real_file_size);
return 1;
}
/*
* mark entry before potentially trimming io_u
*/
if (td_random(td) && file_randommap(td, io_u->file))
mark_random_map(td, io_u);
out:
dprint_io_u(io_u, "fill_io_u");
td->zone_bytes += io_u->buflen;
return 0;
}
static void __io_u_mark_map(unsigned int *map, unsigned int nr)
{
int idx = 0;
switch (nr) {
default:
idx = 6;
break;
case 33 ... 64:
idx = 5;
break;
case 17 ... 32:
idx = 4;
break;
case 9 ... 16:
idx = 3;
break;
case 5 ... 8:
idx = 2;
break;
case 1 ... 4:
idx = 1;
case 0:
break;
}
map[idx]++;
}
void io_u_mark_submit(struct thread_data *td, unsigned int nr)
{
__io_u_mark_map(td->ts.io_u_submit, nr);
td->ts.total_submit++;
}
void io_u_mark_complete(struct thread_data *td, unsigned int nr)
{
__io_u_mark_map(td->ts.io_u_complete, nr);
td->ts.total_complete++;
}
void io_u_mark_depth(struct thread_data *td, unsigned int nr)
{
int idx = 0;
switch (td->cur_depth) {
default:
idx = 6;
break;
case 32 ... 63:
idx = 5;
break;
case 16 ... 31:
idx = 4;
break;
case 8 ... 15:
idx = 3;
break;
case 4 ... 7:
idx = 2;
break;
case 2 ... 3:
idx = 1;
case 1:
break;
}
td->ts.io_u_map[idx] += nr;
}
static void io_u_mark_lat_usec(struct thread_data *td, unsigned long usec)
{
int idx = 0;
assert(usec < 1000);
switch (usec) {
case 750 ... 999:
idx = 9;
break;
case 500 ... 749:
idx = 8;
break;
case 250 ... 499:
idx = 7;
break;
case 100 ... 249:
idx = 6;
break;
case 50 ... 99:
idx = 5;
break;
case 20 ... 49:
idx = 4;
break;
case 10 ... 19:
idx = 3;
break;
case 4 ... 9:
idx = 2;
break;
case 2 ... 3:
idx = 1;
case 0 ... 1:
break;
}
assert(idx < FIO_IO_U_LAT_U_NR);
td->ts.io_u_lat_u[idx]++;
}
static void io_u_mark_lat_msec(struct thread_data *td, unsigned long msec)
{
int idx = 0;
switch (msec) {
default:
idx = 11;
break;
case 1000 ... 1999:
idx = 10;
break;
case 750 ... 999:
idx = 9;
break;
case 500 ... 749:
idx = 8;
break;
case 250 ... 499:
idx = 7;
break;
case 100 ... 249:
idx = 6;
break;
case 50 ... 99:
idx = 5;
break;
case 20 ... 49:
idx = 4;
break;
case 10 ... 19:
idx = 3;
break;
case 4 ... 9:
idx = 2;
break;
case 2 ... 3:
idx = 1;
case 0 ... 1:
break;
}
assert(idx < FIO_IO_U_LAT_M_NR);
td->ts.io_u_lat_m[idx]++;
}
static void io_u_mark_latency(struct thread_data *td, unsigned long usec)
{
if (usec < 1000)
io_u_mark_lat_usec(td, usec);
else
io_u_mark_lat_msec(td, usec / 1000);
}
/*
* Get next file to service by choosing one at random
*/
static struct fio_file *get_next_file_rand(struct thread_data *td,
enum fio_file_flags goodf,
enum fio_file_flags badf)
{
struct fio_file *f;
int fno;
do {
int opened = 0;
unsigned long r;
r = __rand(&td->next_file_state);
fno = (unsigned int) ((double) td->o.nr_files
* (r / (FRAND_MAX + 1.0)));
f = td->files[fno];
if (fio_file_done(f))
continue;
if (!fio_file_open(f)) {
int err;
if (td->nr_open_files >= td->o.open_files)
return ERR_PTR(-EBUSY);
err = td_io_open_file(td, f);
if (err)
continue;
opened = 1;
}
if ((!goodf || (f->flags & goodf)) && !(f->flags & badf)) {
dprint(FD_FILE, "get_next_file_rand: %p\n", f);
return f;
}
if (opened)
td_io_close_file(td, f);
} while (1);
}
/*
* Get next file to service by doing round robin between all available ones
*/
static struct fio_file *get_next_file_rr(struct thread_data *td, int goodf,
int badf)
{
unsigned int old_next_file = td->next_file;
struct fio_file *f;
do {
int opened = 0;
f = td->files[td->next_file];
td->next_file++;
if (td->next_file >= td->o.nr_files)
td->next_file = 0;
dprint(FD_FILE, "trying file %s %x\n", f->file_name, f->flags);
if (fio_file_done(f)) {
f = NULL;
continue;
}
if (!fio_file_open(f)) {
int err;
if (td->nr_open_files >= td->o.open_files)
return ERR_PTR(-EBUSY);
err = td_io_open_file(td, f);
if (err) {
dprint(FD_FILE, "error %d on open of %s\n",
err, f->file_name);
f = NULL;
continue;
}
opened = 1;
}
dprint(FD_FILE, "goodf=%x, badf=%x, ff=%x\n", goodf, badf,
f->flags);
if ((!goodf || (f->flags & goodf)) && !(f->flags & badf))
break;
if (opened)
td_io_close_file(td, f);
f = NULL;
} while (td->next_file != old_next_file);
dprint(FD_FILE, "get_next_file_rr: %p\n", f);
return f;
}
static struct fio_file *__get_next_file(struct thread_data *td)
{
struct fio_file *f;
assert(td->o.nr_files <= td->files_index);
if (td->nr_done_files >= td->o.nr_files) {
dprint(FD_FILE, "get_next_file: nr_open=%d, nr_done=%d,"
" nr_files=%d\n", td->nr_open_files,
td->nr_done_files,
td->o.nr_files);
return NULL;
}
f = td->file_service_file;
if (f && fio_file_open(f) && !fio_file_closing(f)) {
if (td->o.file_service_type == FIO_FSERVICE_SEQ)
goto out;
if (td->file_service_left--)
goto out;
}
if (td->o.file_service_type == FIO_FSERVICE_RR ||
td->o.file_service_type == FIO_FSERVICE_SEQ)
f = get_next_file_rr(td, FIO_FILE_open, FIO_FILE_closing);
else
f = get_next_file_rand(td, FIO_FILE_open, FIO_FILE_closing);
if (IS_ERR(f))
return f;
td->file_service_file = f;
td->file_service_left = td->file_service_nr - 1;
out:
if (f)
dprint(FD_FILE, "get_next_file: %p [%s]\n", f, f->file_name);
else
dprint(FD_FILE, "get_next_file: NULL\n");
return f;
}
static struct fio_file *get_next_file(struct thread_data *td)
{
if (td->flags & TD_F_PROFILE_OPS) {
struct prof_io_ops *ops = &td->prof_io_ops;
if (ops->get_next_file)
return ops->get_next_file(td);
}
return __get_next_file(td);
}
static long set_io_u_file(struct thread_data *td, struct io_u *io_u)
{
struct fio_file *f;
do {
f = get_next_file(td);
if (IS_ERR_OR_NULL(f))
return PTR_ERR(f);
io_u->file = f;
get_file(f);
if (!fill_io_u(td, io_u))
break;
put_file_log(td, f);
td_io_close_file(td, f);
io_u->file = NULL;
fio_file_set_done(f);
td->nr_done_files++;
dprint(FD_FILE, "%s: is done (%d of %d)\n", f->file_name,
td->nr_done_files, td->o.nr_files);
} while (1);
return 0;
}
static void lat_fatal(struct thread_data *td, struct io_completion_data *icd,
unsigned long tusec, unsigned long max_usec)
{
if (!td->error)
log_err("fio: latency of %lu usec exceeds specified max (%lu usec)\n", tusec, max_usec);
td_verror(td, ETIMEDOUT, "max latency exceeded");
icd->error = ETIMEDOUT;
}
static void lat_new_cycle(struct thread_data *td)
{
fio_gettime(&td->latency_ts, NULL);
td->latency_ios = ddir_rw_sum(td->io_blocks);
td->latency_failed = 0;
}
/*
* We had an IO outside the latency target. Reduce the queue depth. If we
* are at QD=1, then it's time to give up.
*/
static int __lat_target_failed(struct thread_data *td)
{
if (td->latency_qd == 1)
return 1;
td->latency_qd_high = td->latency_qd;
if (td->latency_qd == td->latency_qd_low)
td->latency_qd_low--;
td->latency_qd = (td->latency_qd + td->latency_qd_low) / 2;
dprint(FD_RATE, "Ramped down: %d %d %d\n", td->latency_qd_low, td->latency_qd, td->latency_qd_high);
/*
* When we ramp QD down, quiesce existing IO to prevent
* a storm of ramp downs due to pending higher depth.
*/
io_u_quiesce(td);
lat_new_cycle(td);
return 0;
}
static int lat_target_failed(struct thread_data *td)
{
if (td->o.latency_percentile.u.f == 100.0)
return __lat_target_failed(td);
td->latency_failed++;
return 0;
}
void lat_target_init(struct thread_data *td)
{
td->latency_end_run = 0;
if (td->o.latency_target) {
dprint(FD_RATE, "Latency target=%llu\n", td->o.latency_target);
fio_gettime(&td->latency_ts, NULL);
td->latency_qd = 1;
td->latency_qd_high = td->o.iodepth;
td->latency_qd_low = 1;
td->latency_ios = ddir_rw_sum(td->io_blocks);
} else
td->latency_qd = td->o.iodepth;
}
void lat_target_reset(struct thread_data *td)
{
if (!td->latency_end_run)
lat_target_init(td);
}
static void lat_target_success(struct thread_data *td)
{
const unsigned int qd = td->latency_qd;
struct thread_options *o = &td->o;
td->latency_qd_low = td->latency_qd;
/*
* If we haven't failed yet, we double up to a failing value instead
* of bisecting from highest possible queue depth. If we have set
* a limit other than td->o.iodepth, bisect between that.
*/
if (td->latency_qd_high != o->iodepth)
td->latency_qd = (td->latency_qd + td->latency_qd_high) / 2;
else
td->latency_qd *= 2;
if (td->latency_qd > o->iodepth)
td->latency_qd = o->iodepth;
dprint(FD_RATE, "Ramped up: %d %d %d\n", td->latency_qd_low, td->latency_qd, td->latency_qd_high);
/*
* Same as last one, we are done. Let it run a latency cycle, so
* we get only the results from the targeted depth.
*/
if (td->latency_qd == qd) {
if (td->latency_end_run) {
dprint(FD_RATE, "We are done\n");
td->done = 1;
} else {
dprint(FD_RATE, "Quiesce and final run\n");
io_u_quiesce(td);
td->latency_end_run = 1;
reset_all_stats(td);
reset_io_stats(td);
}
}
lat_new_cycle(td);
}
/*
* Check if we can bump the queue depth
*/
void lat_target_check(struct thread_data *td)
{
uint64_t usec_window;
uint64_t ios;
double success_ios;
usec_window = utime_since_now(&td->latency_ts);
if (usec_window < td->o.latency_window)
return;
ios = ddir_rw_sum(td->io_blocks) - td->latency_ios;
success_ios = (double) (ios - td->latency_failed) / (double) ios;
success_ios *= 100.0;
dprint(FD_RATE, "Success rate: %.2f%% (target %.2f%%)\n", success_ios, td->o.latency_percentile.u.f);
if (success_ios >= td->o.latency_percentile.u.f)
lat_target_success(td);
else
__lat_target_failed(td);
}
/*
* If latency target is enabled, we might be ramping up or down and not
* using the full queue depth available.
*/
int queue_full(const struct thread_data *td)
{
const int qempty = io_u_qempty(&td->io_u_freelist);
if (qempty)
return 1;
if (!td->o.latency_target)
return 0;
return td->cur_depth >= td->latency_qd;
}
struct io_u *__get_io_u(struct thread_data *td)
{
struct io_u *io_u = NULL;
if (td->stop_io)
return NULL;
td_io_u_lock(td);
again:
if (!io_u_rempty(&td->io_u_requeues))
io_u = io_u_rpop(&td->io_u_requeues);
else if (!queue_full(td)) {
io_u = io_u_qpop(&td->io_u_freelist);
io_u->file = NULL;
io_u->buflen = 0;
io_u->resid = 0;
io_u->end_io = NULL;
}
if (io_u) {
assert(io_u->flags & IO_U_F_FREE);
io_u->flags &= ~(IO_U_F_FREE | IO_U_F_NO_FILE_PUT |
IO_U_F_TRIMMED | IO_U_F_BARRIER |
IO_U_F_VER_LIST);
io_u->error = 0;
io_u->acct_ddir = -1;
td->cur_depth++;
io_u->flags |= IO_U_F_IN_CUR_DEPTH;
io_u->ipo = NULL;
} else if (td->o.verify_async) {
/*
* We ran out, wait for async verify threads to finish and
* return one
*/
pthread_cond_wait(&td->free_cond, &td->io_u_lock);
goto again;
}
td_io_u_unlock(td);
return io_u;
}
static int check_get_trim(struct thread_data *td, struct io_u *io_u)
{
if (!(td->flags & TD_F_TRIM_BACKLOG))
return 0;
if (td->trim_entries) {
int get_trim = 0;
if (td->trim_batch) {
td->trim_batch--;
get_trim = 1;
} else if (!(td->io_hist_len % td->o.trim_backlog) &&
td->last_ddir != DDIR_READ) {
td->trim_batch = td->o.trim_batch;
if (!td->trim_batch)
td->trim_batch = td->o.trim_backlog;
get_trim = 1;
}
if (get_trim && !get_next_trim(td, io_u))
return 1;
}
return 0;
}
static int check_get_verify(struct thread_data *td, struct io_u *io_u)
{
if (!(td->flags & TD_F_VER_BACKLOG))
return 0;
if (td->io_hist_len) {
int get_verify = 0;
if (td->verify_batch)
get_verify = 1;
else if (!(td->io_hist_len % td->o.verify_backlog) &&
td->last_ddir != DDIR_READ) {
td->verify_batch = td->o.verify_batch;
if (!td->verify_batch)
td->verify_batch = td->o.verify_backlog;
get_verify = 1;
}
if (get_verify && !get_next_verify(td, io_u)) {
td->verify_batch--;
return 1;
}
}
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;
uint64_t boffset;
unsigned int offset;
void *p, *end;
if (!nr_blocks)
return;
p = io_u->xfer_buf;
boffset = io_u->offset;
io_u->buf_filled_len = 0;
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(uint64_t) - 1);
if (offset >= 512 - sizeof(uint64_t))
offset -= sizeof(uint64_t);
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 io_u *get_io_u(struct thread_data *td)
{
struct fio_file *f;
struct io_u *io_u;
int do_scramble = 0;
long ret = 0;
io_u = __get_io_u(td);
if (!io_u) {
dprint(FD_IO, "__get_io_u failed\n");
return NULL;
}
if (check_get_verify(td, io_u))
goto out;
if (check_get_trim(td, io_u))
goto out;
/*
* from a requeue, io_u already setup
*/
if (io_u->file)
goto out;
/*
* If using an iolog, grab next piece if any available.
*/
if (td->flags & TD_F_READ_IOLOG) {
if (read_iolog_get(td, io_u))
goto err_put;
} else if (set_io_u_file(td, io_u)) {
ret = -EBUSY;
dprint(FD_IO, "io_u %p, setting file failed\n", io_u);
goto err_put;
}
f = io_u->file;
if (!f) {
dprint(FD_IO, "io_u %p, setting file failed\n", io_u);
goto err_put;
}
assert(fio_file_open(f));
if (ddir_rw(io_u->ddir)) {
if (!io_u->buflen && !(td->io_ops->flags & FIO_NOIO)) {
dprint(FD_IO, "get_io_u: zero buflen on %p\n", io_u);
goto err_put;
}
f->last_start[io_u->ddir] = io_u->offset;
f->last_pos[io_u->ddir] = io_u->offset + io_u->buflen;
if (io_u->ddir == DDIR_WRITE) {
if (td->flags & TD_F_REFILL_BUFFERS) {
io_u_fill_buffer(td, io_u,
td->o.min_bs[DDIR_WRITE],
io_u->xfer_buflen);
} else if ((td->flags & TD_F_SCRAMBLE_BUFFERS) &&
!(td->flags & TD_F_COMPRESS))
do_scramble = 1;
if (td->flags & TD_F_VER_NONE) {
populate_verify_io_u(td, io_u);
do_scramble = 0;
}
} 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.
*/
io_u->buf_filled_len = 0;
}
}
/*
* Set io data pointers.
*/
io_u->xfer_buf = io_u->buf;
io_u->xfer_buflen = io_u->buflen;
out:
assert(io_u->file);
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:
dprint(FD_IO, "get_io_u failed\n");
put_io_u(td, io_u);
return ERR_PTR(ret);
}
void io_u_log_error(struct thread_data *td, struct io_u *io_u)
{
enum error_type_bit eb = td_error_type(io_u->ddir, io_u->error);
if (td_non_fatal_error(td, eb, io_u->error) && !td->o.error_dump)
return;
log_err("fio: io_u error%s%s: %s: %s offset=%llu, buflen=%lu\n",
io_u->file ? " on file " : "",
io_u->file ? io_u->file->file_name : "",
strerror(io_u->error),
io_ddir_name(io_u->ddir),
io_u->offset, io_u->xfer_buflen);
if (!td->error)
td_verror(td, io_u->error, "io_u error");
}
static inline int gtod_reduce(struct thread_data *td)
{
return td->o.disable_clat && td->o.disable_lat && td->o.disable_slat
&& td->o.disable_bw;
}
static void account_io_completion(struct thread_data *td, struct io_u *io_u,
struct io_completion_data *icd,
const enum fio_ddir idx, unsigned int bytes)
{
unsigned long lusec = 0;
if (!gtod_reduce(td))
lusec = utime_since(&io_u->issue_time, &icd->time);
if (!td->o.disable_lat) {
unsigned long tusec;
tusec = utime_since(&io_u->start_time, &icd->time);
add_lat_sample(td, idx, tusec, bytes, io_u->offset);
if (td->flags & TD_F_PROFILE_OPS) {
struct prof_io_ops *ops = &td->prof_io_ops;
if (ops->io_u_lat)
icd->error = ops->io_u_lat(td, tusec);
}
if (td->o.max_latency && tusec > td->o.max_latency)
lat_fatal(td, icd, tusec, td->o.max_latency);
if (td->o.latency_target && tusec > td->o.latency_target) {
if (lat_target_failed(td))
lat_fatal(td, icd, tusec, td->o.latency_target);
}
}
if (!td->o.disable_clat) {
add_clat_sample(td, idx, lusec, bytes, io_u->offset);
io_u_mark_latency(td, lusec);
}
if (!td->o.disable_bw)
add_bw_sample(td, idx, bytes, &icd->time);
if (!gtod_reduce(td))
add_iops_sample(td, idx, bytes, &icd->time);
}
static long long usec_for_io(struct thread_data *td, enum fio_ddir ddir)
{
uint64_t secs, remainder, bps, bytes;
bytes = td->this_io_bytes[ddir];
bps = td->rate_bps[ddir];
secs = bytes / bps;
remainder = bytes % bps;
return remainder * 1000000 / bps + secs * 1000000;
}
static void io_completed(struct thread_data *td, struct io_u **io_u_ptr,
struct io_completion_data *icd)
{
struct io_u *io_u = *io_u_ptr;
enum fio_ddir ddir = io_u->ddir;
struct fio_file *f = io_u->file;
dprint_io_u(io_u, "io complete");
td_io_u_lock(td);
assert(io_u->flags & IO_U_F_FLIGHT);
io_u->flags &= ~(IO_U_F_FLIGHT | IO_U_F_BUSY_OK);
/*
* Mark IO ok to verify
*/
if (io_u->ipo) {
/*
* Remove errored entry from the verification list
*/
if (io_u->error)
unlog_io_piece(td, io_u);
else {
io_u->ipo->flags &= ~IP_F_IN_FLIGHT;
write_barrier();
}
}
td_io_u_unlock(td);
if (ddir_sync(ddir)) {
td->last_was_sync = 1;
if (f) {
f->first_write = -1ULL;
f->last_write = -1ULL;
}
return;
}
td->last_was_sync = 0;
td->last_ddir = ddir;
if (!io_u->error && ddir_rw(ddir)) {
unsigned int bytes = io_u->buflen - io_u->resid;
const enum fio_ddir oddir = ddir ^ 1;
int ret;
td->io_blocks[ddir]++;
td->this_io_blocks[ddir]++;
td->io_bytes[ddir] += bytes;
if (!(io_u->flags & IO_U_F_VER_LIST))
td->this_io_bytes[ddir] += bytes;
if (ddir == DDIR_WRITE) {
if (f) {
if (f->first_write == -1ULL ||
io_u->offset < f->first_write)
f->first_write = io_u->offset;
if (f->last_write == -1ULL ||
((io_u->offset + bytes) > f->last_write))
f->last_write = io_u->offset + bytes;
}
if (td->last_write_comp) {
int idx = td->last_write_idx++;
td->last_write_comp[idx] = io_u->offset;
if (td->last_write_idx == td->o.iodepth)
td->last_write_idx = 0;
}
}
if (ramp_time_over(td) && (td->runstate == TD_RUNNING ||
td->runstate == TD_VERIFYING)) {
account_io_completion(td, io_u, icd, ddir, bytes);
if (__should_check_rate(td, ddir)) {
td->rate_pending_usleep[ddir] =
(usec_for_io(td, ddir) -
utime_since_now(&td->start));
}
if (ddir != DDIR_TRIM &&
__should_check_rate(td, oddir)) {
td->rate_pending_usleep[oddir] =
(usec_for_io(td, oddir) -
utime_since_now(&td->start));
}
}
icd->bytes_done[ddir] += bytes;
if (io_u->end_io) {
ret = io_u->end_io(td, io_u_ptr);
io_u = *io_u_ptr;
if (ret && !icd->error)
icd->error = ret;
}
} else if (io_u->error) {
icd->error = io_u->error;
io_u_log_error(td, io_u);
}
if (icd->error) {
enum error_type_bit eb = td_error_type(ddir, icd->error);
if (!td_non_fatal_error(td, eb, icd->error))
return;
/*
* If there is a non_fatal error, then add to the error count
* and clear all the errors.
*/
update_error_count(td, icd->error);
td_clear_error(td);
icd->error = 0;
if (io_u)
io_u->error = 0;
}
}
static void init_icd(struct thread_data *td, struct io_completion_data *icd,
int nr)
{
int ddir;
if (!gtod_reduce(td))
fio_gettime(&icd->time, NULL);
icd->nr = nr;
icd->error = 0;
for (ddir = DDIR_READ; ddir < DDIR_RWDIR_CNT; ddir++)
icd->bytes_done[ddir] = 0;
}
static void ios_completed(struct thread_data *td,
struct io_completion_data *icd)
{
struct io_u *io_u;
int i;
for (i = 0; i < icd->nr; i++) {
io_u = td->io_ops->event(td, i);
io_completed(td, &io_u, icd);
if (io_u)
put_io_u(td, io_u);
}
}
/*
* Complete a single io_u for the sync engines.
*/
int io_u_sync_complete(struct thread_data *td, struct io_u *io_u,
uint64_t *bytes)
{
struct io_completion_data icd;
init_icd(td, &icd, 1);
io_completed(td, &io_u, &icd);
if (io_u)
put_io_u(td, io_u);
if (icd.error) {
td_verror(td, icd.error, "io_u_sync_complete");
return -1;
}
if (bytes) {
int ddir;
for (ddir = DDIR_READ; ddir < DDIR_RWDIR_CNT; ddir++)
bytes[ddir] += icd.bytes_done[ddir];
}
return 0;
}
/*
* Called to complete min_events number of io for the async engines.
*/
int io_u_queued_complete(struct thread_data *td, int min_evts,
uint64_t *bytes)
{
struct io_completion_data icd;
struct timespec *tvp = NULL;
int ret;
struct timespec ts = { .tv_sec = 0, .tv_nsec = 0, };
dprint(FD_IO, "io_u_queued_completed: min=%d\n", min_evts);
if (!min_evts)
tvp = &ts;
else if (min_evts > td->cur_depth)
min_evts = td->cur_depth;
ret = td_io_getevents(td, min_evts, td->o.iodepth_batch_complete, tvp);
if (ret < 0) {
td_verror(td, -ret, "td_io_getevents");
return ret;
} else if (!ret)
return ret;
init_icd(td, &icd, ret);
ios_completed(td, &icd);
if (icd.error) {
td_verror(td, icd.error, "io_u_queued_complete");
return -1;
}
if (bytes) {
int ddir;
for (ddir = DDIR_READ; ddir < DDIR_RWDIR_CNT; ddir++)
bytes[ddir] += icd.bytes_done[ddir];
}
return 0;
}
/*
* Call when io_u is really queued, to update the submission latency.
*/
void io_u_queued(struct thread_data *td, struct io_u *io_u)
{
if (!td->o.disable_slat) {
unsigned long slat_time;
slat_time = utime_since(&io_u->start_time, &io_u->issue_time);
add_slat_sample(td, io_u->ddir, slat_time, io_u->xfer_buflen,
io_u->offset);
}
}
/*
* See if we should reuse the last seed, if dedupe is enabled
*/
static struct frand_state *get_buf_state(struct thread_data *td)
{
unsigned int v;
unsigned long r;
if (!td->o.dedupe_percentage)
return &td->buf_state;
else if (td->o.dedupe_percentage == 100)
return &td->buf_state_prev;
r = __rand(&td->dedupe_state);
v = 1 + (int) (100.0 * (r / (FRAND_MAX + 1.0)));
if (v <= td->o.dedupe_percentage)
return &td->buf_state_prev;
return &td->buf_state;
}
static void save_buf_state(struct thread_data *td, struct frand_state *rs)
{
if (rs == &td->buf_state)
frand_copy(&td->buf_state_prev, rs);
}
void fill_io_buffer(struct thread_data *td, void *buf, unsigned int min_write,
unsigned int max_bs)
{
struct thread_options *o = &td->o;
if (o->compress_percentage || o->dedupe_percentage) {
unsigned int perc = td->o.compress_percentage;
struct frand_state *rs;
unsigned int left = max_bs;
do {
rs = get_buf_state(td);
min_write = min(min_write, left);
if (perc) {
unsigned int seg = min_write;
seg = min(min_write, td->o.compress_chunk);
if (!seg)
seg = min_write;
fill_random_buf_percentage(rs, buf, perc, seg,
min_write, o->buffer_pattern,
o->buffer_pattern_bytes);
} else
fill_random_buf(rs, buf, min_write);
buf += min_write;
left -= min_write;
save_buf_state(td, rs);
} while (left);
} else if (o->buffer_pattern_bytes)
fill_buffer_pattern(td, buf, max_bs);
else
memset(buf, 0, max_bs);
}
/*
* "randomly" fill the buffer contents
*/
void io_u_fill_buffer(struct thread_data *td, struct io_u *io_u,
unsigned int min_write, unsigned int max_bs)
{
io_u->buf_filled_len = 0;
fill_io_buffer(td, io_u->buf, min_write, max_bs);
}