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Rebase master to b117

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This commit is contained in:
Brian Behlendorf
2009-07-02 15:44:48 -07:00
parent d164b20935
commit 9babb37438
103 changed files with 7629 additions and 4093 deletions
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module/zfs/vdev_queue.c
+23 -19
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@@ -48,10 +48,11 @@ int zfs_vdev_time_shift = 6;
int zfs_vdev_ramp_rate = 2;
/*
* i/os will be aggregated into a single large i/o up to
* zfs_vdev_aggregation_limit bytes long.
* To reduce IOPs, we aggregate small adjacent i/os into one large i/o.
* For read i/os, we also aggregate across small adjacency gaps.
*/
int zfs_vdev_aggregation_limit = SPA_MAXBLOCKSIZE;
int zfs_vdev_read_gap_limit = 32 << 10;
/*
* Virtual device vector for disk I/O scheduling.
@@ -159,16 +160,23 @@ vdev_queue_agg_io_done(zio_t *aio)
zio_buf_free(aio->io_data, aio->io_size);
}
#define IS_ADJACENT(io, nio) \
((io)->io_offset + (io)->io_size == (nio)->io_offset)
/*
* Compute the range spanned by two i/os, which is the endpoint of the last
* (lio->io_offset + lio->io_size) minus start of the first (fio->io_offset).
* Conveniently, the gap between fio and lio is given by -IO_SPAN(lio, fio);
* thus fio and lio are adjacent if and only if IO_SPAN(lio, fio) == 0.
*/
#define IO_SPAN(fio, lio) ((lio)->io_offset + (lio)->io_size - (fio)->io_offset)
#define IO_GAP(fio, lio) (-IO_SPAN(lio, fio))
static zio_t *
vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit)
{
zio_t *fio, *lio, *aio, *dio, *nio;
avl_tree_t *t;
uint64_t size;
int flags;
uint64_t maxspan = zfs_vdev_aggregation_limit;
uint64_t maxgap;
ASSERT(MUTEX_HELD(&vq->vq_lock));
@@ -179,8 +187,8 @@ vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit)
fio = lio = avl_first(&vq->vq_deadline_tree);
t = fio->io_vdev_tree;
size = fio->io_size;
flags = fio->io_flags & ZIO_FLAG_AGG_INHERIT;
maxgap = (t == &vq->vq_read_tree) ? zfs_vdev_read_gap_limit : 0;
if (!(flags & ZIO_FLAG_DONT_AGGREGATE)) {
/*
@@ -191,22 +199,18 @@ vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit)
* scrub/resilver, can be preserved in the aggregate.
*/
while ((dio = AVL_PREV(t, fio)) != NULL &&
IS_ADJACENT(dio, fio) &&
(dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags &&
size + dio->io_size <= zfs_vdev_aggregation_limit) {
IO_SPAN(dio, lio) <= maxspan && IO_GAP(dio, fio) <= maxgap)
fio = dio;
size += dio->io_size;
}
while ((dio = AVL_NEXT(t, lio)) != NULL &&
IS_ADJACENT(lio, dio) &&
(dio->io_flags & ZIO_FLAG_AGG_INHERIT) == flags &&
size + dio->io_size <= zfs_vdev_aggregation_limit) {
IO_SPAN(fio, dio) <= maxspan && IO_GAP(lio, dio) <= maxgap)
lio = dio;
size += dio->io_size;
}
}
if (fio != lio) {
uint64_t size = IO_SPAN(fio, lio);
ASSERT(size <= zfs_vdev_aggregation_limit);
aio = zio_vdev_delegated_io(fio->io_vd, fio->io_offset,
@@ -214,9 +218,10 @@ vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit)
flags | ZIO_FLAG_DONT_CACHE | ZIO_FLAG_DONT_QUEUE,
vdev_queue_agg_io_done, NULL);
/* We want to process lio, then stop */
lio = AVL_NEXT(t, lio);
for (dio = fio; dio != lio; dio = nio) {
nio = fio;
do {
dio = nio;
nio = AVL_NEXT(t, dio);
ASSERT(dio->io_type == aio->io_type);
ASSERT(dio->io_vdev_tree == t);
@@ -224,13 +229,12 @@ vdev_queue_io_to_issue(vdev_queue_t *vq, uint64_t pending_limit)
bcopy(dio->io_data, (char *)aio->io_data +
(dio->io_offset - aio->io_offset),
dio->io_size);
nio = AVL_NEXT(t, dio);
zio_add_child(dio, aio);
vdev_queue_io_remove(vq, dio);
zio_vdev_io_bypass(dio);
zio_execute(dio);
}
} while (dio != lio);
avl_add(&vq->vq_pending_tree, aio);