On 2020/04/24 6:38, Alexey Dobriyan wrote:
> Currently threads tap into each other zones even if their working areas
> as defined by [f->file_offset, f->file_offset + f->io_size) don't intersect.
>
> This should remove unnecessary quiescing in iodepth > 1 workloads.
>
> Signed-off-by: Alexey Dobriyan (SK hynix) <adobriyan@xxxxxxxxx>
> ---
>
> file.h | 3 +++
> zbd.c | 42 ++++++++++++++++++++++++++++++++----------
> 2 files changed, 35 insertions(+), 10 deletions(-)
>
> --- a/file.h
> +++ b/file.h
> @@ -104,6 +104,9 @@ struct fio_file {
> * Zoned block device information. See also zonemode=zbd.
> */
> struct zoned_block_device_info *zbd_info;
> + /* zonemode=zbd working area */
> + uint32_t min_zone; /* inclusive */
> + uint32_t max_zone; /* exclusive */
For simplicity, what about having both inclusive ?
>
> /*
> * Track last end and last start of IO for a given data direction
> --- a/zbd.c
> +++ b/zbd.c
> @@ -156,8 +156,14 @@ static bool zbd_zone_full(const struct fio_file *f, struct fio_zone_info *z,
> z->wp + required > z->start + f->zbd_info->zone_size;
> }
>
> -static void zone_lock(struct thread_data *td, struct fio_zone_info *z)
> +static void zone_lock(struct thread_data *td, struct fio_file *f, struct fio_zone_info *z)
> {
> + struct zoned_block_device_info *zbd = f->zbd_info;
> + uint32_t nz = z - zbd->zone_info;
> +
> + /* Thread should never lock zones outside its working area. */
> + assert(f->min_zone <= nz && nz < f->max_zone);
> +
> /*
> * Lock the io_u target zone. The zone will be unlocked if io_u offset
> * is changed or when io_u completes and zbd_put_io() executed.
> @@ -289,6 +295,9 @@ static bool zbd_verify_sizes(void)
> (unsigned long long) new_end - f->file_offset);
> f->io_size = new_end - f->file_offset;
> }
> +
> + f->min_zone = zbd_zone_idx(f, f->file_offset);
> + f->max_zone = zbd_zone_idx(f, f->file_offset + f->io_size);
"- 1" to make it inclusive ?
> }
> }
>
> @@ -332,6 +341,17 @@ static int ilog2(uint64_t i)
> return log;
> }
>
> +static uint32_t clamp_u32(uint32_t x, uint32_t min, uint32_t max)
> +{
> + if (x < min) {
> + return min;
> + } else if (x > max) {
> + return max;
> + } else {
> + return x;
> + }
> +}
See below comment.
> +
> /*
> * Initialize f->zbd_info for devices that are not zoned block devices. This
> * allows to execute a ZBD workload against a non-ZBD device.
> @@ -735,7 +755,7 @@ static int zbd_reset_zones(struct thread_data *td, struct fio_file *f,
>
> if (!zbd_zone_swr(z))
> continue;
> - zone_lock(td, z);
> + zone_lock(td, f, z);
> if (all_zones) {
> unsigned int i;
>
> @@ -958,7 +978,7 @@ static struct fio_zone_info *zbd_convert_to_open_zone(struct thread_data *td,
> struct io_u *io_u)
> {
> const uint32_t min_bs = td->o.min_bs[io_u->ddir];
> - const struct fio_file *f = io_u->file;
> + struct fio_file *f = io_u->file;
> struct fio_zone_info *z;
> unsigned int open_zone_idx = -1;
> uint32_t zone_idx, new_zone_idx;
> @@ -975,6 +995,7 @@ static struct fio_zone_info *zbd_convert_to_open_zone(struct thread_data *td,
> } else {
> zone_idx = zbd_zone_idx(f, io_u->offset);
> }
> + zone_idx = clamp_u32(zone_idx, f->min_zone, f->max_zone - 1);
Since this is the only place clamp_u32 is used, I think you could just open code
it here. That plus a comment would make it easier to follow what is going on.
E.g.:
/*
* Limit candidate zones to those contained in the thread working area.
*/
if (zone_idx < f->min_zone)
zone_idx = f->min_zone;
else if (zone_idx > f->max_zone)
zone_idx = f->max_zone;
> dprint(FD_ZBD, "%s(%s): starting from zone %d (offset %lld, buflen %lld)\n",
> __func__, f->file_name, zone_idx, io_u->offset, io_u->buflen);
>
> @@ -989,7 +1010,7 @@ static struct fio_zone_info *zbd_convert_to_open_zone(struct thread_data *td,
>
> z = &f->zbd_info->zone_info[zone_idx];
>
> - zone_lock(td, z);
> + zone_lock(td, f, z);
> pthread_mutex_lock(&f->zbd_info->mutex);
> if (td->o.max_open_zones == 0)
> goto examine_zone;
> @@ -1015,8 +1036,7 @@ static struct fio_zone_info *zbd_convert_to_open_zone(struct thread_data *td,
> if (tmp_idx >= f->zbd_info->num_open_zones)
> tmp_idx = 0;
> tmpz = f->zbd_info->open_zones[tmp_idx];
> -
> - if (is_valid_offset(f, f->zbd_info->zone_info[tmpz].start)) {
> + if (f->min_zone <= tmpz && tmpz < f->max_zone) {
> open_zone_idx = tmp_idx;
> goto found_candidate_zone;
> }
> @@ -1061,11 +1081,11 @@ examine_zone:
> z++;
> if (!is_valid_offset(f, z->start)) {
> /* Wrap-around. */
> - zone_idx = zbd_zone_idx(f, f->file_offset);
> + zone_idx = f->min_zone;
> z = &f->zbd_info->zone_info[zone_idx];
> }
> assert(is_valid_offset(f, z->start));
> - zone_lock(td, z);
> + zone_lock(td, f, z);
> if (z->open)
> continue;
> if (zbd_open_zone(td, io_u, zone_idx))
> @@ -1078,12 +1098,14 @@ examine_zone:
> pthread_mutex_lock(&f->zbd_info->mutex);
> for (i = 0; i < f->zbd_info->num_open_zones; i++) {
> zone_idx = f->zbd_info->open_zones[i];
> + if (!(f->min_zone <= zone_idx && zone_idx < f->max_zone))
> + continue;
if (zone_idx < f->min_zone || zone_idx >= f->max_zone))
continue;
is I think easier to read.
> pthread_mutex_unlock(&f->zbd_info->mutex);
> pthread_mutex_unlock(&z->mutex);
>
> z = &f->zbd_info->zone_info[zone_idx];
>
> - zone_lock(td, z);
> + zone_lock(td, f, z);
> if (z->wp + min_bs <= (z+1)->start)
> goto out;
> pthread_mutex_lock(&f->zbd_info->mutex);
> @@ -1409,7 +1431,7 @@ enum io_u_action zbd_adjust_block(struct thread_data *td, struct io_u *io_u)
>
> zbd_check_swd(f);
>
> - zone_lock(td, zb);
> + zone_lock(td, f, zb);
>
> switch (io_u->ddir) {
> case DDIR_READ:
>
--
Damien Le Moal
Western Digital Research
