Commit fb0259fb ("zbd: Ensure first I/O is write for random read/write to
sequential zones") introduced a step to change direction of io_u from
read to write when that is the first I/O of the random read/write
workload to zoned block devices. However, such direction adjustment
results in inconsistent I/O length when read block size and write block
size are different.
To avoid the inconsistency between I/O direction and I/O length,
adjust the I/O direction before the I/O length is set. Move the step
from zbd_adjust_block() to set_rw_ddir(). To minimize changes in
set_rw_ddir(), introduce zbd_adjust_ddir() helper function.
Fixes: fb0259fb ("zbd: Ensure first I/O is write for random read/write to sequential zones")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
---
io_u.c | 2 ++
zbd.c | 40 ++++++++++++++++++++++++++++++----------
zbd.h | 2 ++
3 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/io_u.c b/io_u.c
index 5d62a76c..18e94617 100644
--- a/io_u.c
+++ b/io_u.c
@@ -746,6 +746,8 @@ static void set_rw_ddir(struct thread_data *td, struct io_u *io_u)
{
enum fio_ddir ddir = get_rw_ddir(td);
+ ddir = zbd_adjust_ddir(td, io_u, ddir);
+
if (td_trimwrite(td)) {
struct fio_file *f = io_u->file;
if (f->last_pos[DDIR_WRITE] == f->last_pos[DDIR_TRIM])
diff --git a/zbd.c b/zbd.c
index de0c5bf4..8dc3c397 100644
--- a/zbd.c
+++ b/zbd.c
@@ -1331,6 +1331,36 @@ void setup_zbd_zone_mode(struct thread_data *td, struct io_u *io_u)
}
}
+/**
+ * zbd_adjust_ddir - Adjust an I/O direction for zonedmode=zbd.
+ *
+ * @td: FIO thread data.
+ * @io_u: FIO I/O unit.
+ * @ddir: I/O direction before adjustment.
+ *
+ * Return adjusted I/O direction.
+ */
+enum fio_ddir zbd_adjust_ddir(struct thread_data *td, struct io_u *io_u,
+ enum fio_ddir ddir)
+{
+ /*
+ * In case read direction is chosen for the first random I/O, fio with
+ * zonemode=zbd stops because no data can be read from zoned block
+ * devices with all empty zones. Overwrite the first I/O direction as
+ * write to make sure data to read exists.
+ */
+ if (td->o.zone_mode != ZONE_MODE_ZBD ||
+ ddir != DDIR_READ ||
+ !td_rw(td))
+ return ddir;
+
+ if (io_u->file->zbd_info->sectors_with_data ||
+ td->o.read_beyond_wp)
+ return DDIR_READ;
+
+ return DDIR_WRITE;
+}
+
/**
* zbd_adjust_block - adjust the offset and length as necessary for ZBD drives
* @td: FIO thread data.
@@ -1364,16 +1394,6 @@ enum io_u_action zbd_adjust_block(struct thread_data *td, struct io_u *io_u)
if (!zbd_zone_swr(zb))
return io_u_accept;
- /*
- * In case read direction is chosen for the first random I/O, fio with
- * zonemode=zbd stops because no data can be read from zoned block
- * devices with all empty zones. Overwrite the first I/O direction as
- * write to make sure data to read exists.
- */
- if (td_rw(td) && !f->zbd_info->sectors_with_data
- && !td->o.read_beyond_wp)
- io_u->ddir = DDIR_WRITE;
-
/*
* Accept the I/O offset for reads if reading beyond the write pointer
* is enabled.
diff --git a/zbd.h b/zbd.h
index 4eaf902e..5a660399 100644
--- a/zbd.h
+++ b/zbd.h
@@ -82,6 +82,8 @@ int zbd_init(struct thread_data *td);
void zbd_file_reset(struct thread_data *td, struct fio_file *f);
bool zbd_unaligned_write(int error_code);
void setup_zbd_zone_mode(struct thread_data *td, struct io_u *io_u);
+enum fio_ddir zbd_adjust_ddir(struct thread_data *td, struct io_u *io_u,
+ enum fio_ddir ddir);
enum io_u_action zbd_adjust_block(struct thread_data *td, struct io_u *io_u);
char *zbd_write_status(const struct thread_stat *ts);
--
2.25.2
