xfs: prepare xfs_btree_cur for dynamic cursor heights
Split out the btree level information into a separate struct and put it
at the end of the cursor structure as a VLA. Files with huge data forks
(and in the future, the realtime rmap btree) will require the ability to
support many more levels than a per-AG btree cursor, which means that
we're going to create per-btree type cursor caches to conserve memory
for the more common case.
Note that a subsequent patch actually introduces dynamic cursor heights.
This one merely rearranges the structure to prepare for that.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandan.babu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 1033a95..4a8076e 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -2476,7 +2476,7 @@ DECLARE_EVENT_CLASS(xfs_btree_cur_class,
__entry->btnum = cur->bc_btnum;
__entry->level = level;
__entry->nlevels = cur->bc_nlevels;
- __entry->ptr = cur->bc_ptrs[level];
+ __entry->ptr = cur->bc_levels[level].ptr;
__entry->daddr = bp ? xfs_buf_daddr(bp) : -1;
),
TP_printk("dev %d:%d btree %s level %d/%d ptr %d daddr 0x%llx",