The function zbd_replay_write_order() is called when a read is
issued by fio verification code to compare the read data with the
previously written data. Any data mismatch is marked as a verification
failure.
Since zbd_adjust_block() may change the i/o offset and length
to comply with i/o constrains that zoned model has set,
zbd_replay_write_order() needs to replicate the same adjustment during
verify. The general flow in this function matches the write processing
done in zbd_adjust_block(), but there are some differences. For
example, z->verify_block acts as the pseudo-write pointer during replay
and it needs to be advanced by buflen every time the function called,
but it is advanced by min_bs in the existing code (the value of this
variable is measured in min_bs units).
Fix the issue with verify_block and add more error logging to simplify
troubleshooting of this tricky part of ZBD code.
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@xxxxxxx>
Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
---
zbd.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/zbd.c b/zbd.c
index 44ecb9e0..1ee238e8 100644
--- a/zbd.c
+++ b/zbd.c
@@ -1239,10 +1239,23 @@ static struct fio_zone_info *zbd_replay_write_order(struct thread_data *td,
assert(z);
}
- if (z->verify_block * min_bs >= z->capacity)
+ if (z->verify_block * min_bs >= z->capacity) {
log_err("%s: %d * %d >= %llu\n", f->file_name, z->verify_block,
min_bs, (unsigned long long)z->capacity);
- io_u->offset = z->start + z->verify_block++ * min_bs;
+ /*
+ * If the assertion below fails during a test run, adding
+ * "--experimental_verify=1" to the command line may help.
+ */
+ assert(false);
+ }
+ io_u->offset = z->start + z->verify_block * min_bs;
+ if (io_u->offset + io_u->buflen >= zbd_zone_capacity_end(z)) {
+ log_err("%s: %llu + %llu >= %lu\n", f->file_name, io_u->offset,
+ io_u->buflen, zbd_zone_capacity_end(z));
+ assert(false);
+ }
+ z->verify_block += io_u->buflen / min_bs;
+
return z;
}
--
2.28.0
