Module Name: src
Committed By: jdolecek
Date: Wed Jun 24 16:16:01 UTC 2020
Modified Files:
src/external/cddl/osnet/dist/uts/common/fs/zfs: vdev_queue.c
Log Message:
reduce stack usage in vdev_queue_io_to_issue() - zio_t is about 1KB, and
the function potentially recurses into itself
part of fix for PR kern/55402 by Frank Kardel
To generate a diff of this commit:
cvs rdiff -u -r1.1.1.3 -r1.2 \
src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c
diff -u src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c:1.1.1.3 src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c:1.2
--- src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c:1.1.1.3 Mon May 28 20:52:59 2018
+++ src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_queue.c Wed Jun 24 16:16:01 2020
@@ -798,7 +798,7 @@ vdev_queue_io_to_issue(vdev_queue_t *vq)
zio_priority_t p;
avl_index_t idx;
avl_tree_t *tree;
- zio_t search;
+ zio_t *search;
again:
ASSERT(MUTEX_HELD(&vq->vq_lock));
@@ -817,10 +817,16 @@ again:
* For FIFO queues (sync), issue the i/o with the lowest timestamp.
*/
tree = vdev_queue_class_tree(vq, p);
- search.io_timestamp = 0;
- search.io_offset = vq->vq_last_offset + 1;
- VERIFY3P(avl_find(tree, &search, &idx), ==, NULL);
- zio = avl_nearest(tree, idx, AVL_AFTER);
+ search = kmem_zalloc(sizeof (*search), KM_NOSLEEP);
+ if (search) {
+ search->io_offset = vq->vq_last_offset + 1;
+ VERIFY3P(avl_find(tree, &search, &idx), ==, NULL);
+ kmem_free(search, sizeof (*search));
+ zio = avl_nearest(tree, idx, AVL_AFTER);
+ } else {
+ /* Can't find nearest, fallback to first */
+ zio = NULL;
+ }
if (zio == NULL)
zio = avl_first(tree);
ASSERT3U(zio->io_priority, ==, p);
