From 8e59ceed9f2fdb5bcb25657f3385bc8d658df6f1 Mon Sep 17 00:00:00 2001 From: MigeljanImeri Date: Wed, 1 Nov 2023 11:13:33 -0600 Subject: [PATCH] Fix accounting error for pending sync IO ops in zpool iostat Currently vdev_queue_class_length is responsible for checking how long the queue length is, however, it doesn't check the length when a list is used, rather it just returns whether it is empty or not. To fix this I added a counter variable to vdev_queue_t to keep track of the sync IO ops, and changed vdev_queue_class_length to reference this variable instead. Signed-off-by: MigeljanImeri --- include/sys/vdev_impl.h | 1 + module/zfs/vdev_queue.c | 7 +++++-- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/include/sys/vdev_impl.h b/include/sys/vdev_impl.h index ad9dc3aefd8e..45636a5a1be5 100644 --- a/include/sys/vdev_impl.h +++ b/include/sys/vdev_impl.h @@ -138,6 +138,7 @@ typedef union vdev_queue_class { struct vdev_queue { vdev_t *vq_vdev; vdev_queue_class_t vq_class[ZIO_PRIORITY_NUM_QUEUEABLE]; + ulong_t vq_sync_pending_count[ZIO_PRIORITY_NUM_QUEUEABLE]; avl_tree_t vq_read_offset_tree; avl_tree_t vq_write_offset_tree; uint64_t vq_last_offset; diff --git a/module/zfs/vdev_queue.c b/module/zfs/vdev_queue.c index 08d918467d03..00e23170118b 100644 --- a/module/zfs/vdev_queue.c +++ b/module/zfs/vdev_queue.c @@ -273,8 +273,10 @@ vdev_queue_class_add(vdev_queue_t *vq, zio_t *zio) { zio_priority_t p = zio->io_priority; vq->vq_cqueued |= 1U << p; - if (vdev_queue_class_fifo(p)) + if (vdev_queue_class_fifo(p)) { list_insert_tail(&vq->vq_class[p].vqc_list, zio); + vq->vq_sync_pending_count[p]++; + } else avl_add(&vq->vq_class[p].vqc_tree, zio); } @@ -288,6 +290,7 @@ vdev_queue_class_remove(vdev_queue_t *vq, zio_t *zio) list_t *list = &vq->vq_class[p].vqc_list; list_remove(list, zio); empty = list_is_empty(list); + vq->vq_sync_pending_count[p]--; } else { avl_tree_t *tree = &vq->vq_class[p].vqc_tree; avl_remove(tree, zio); @@ -1069,7 +1072,7 @@ vdev_queue_class_length(vdev_t *vd, zio_priority_t p) { vdev_queue_t *vq = &vd->vdev_queue; if (vdev_queue_class_fifo(p)) - return (list_is_empty(&vq->vq_class[p].vqc_list) == 0); + return (vq->vq_sync_pending_count[p]); else return (avl_numnodes(&vq->vq_class[p].vqc_tree)); }