Btrfs: introduce mark_extent_buffer_accessed
Because an eb can have multiple pages we need to make sure that all pages within
the eb are markes as accessed, since releasepage can be called against any page
in the eb. This will keep us from possibly evicting hot eb's when we're doing
larger than pagesize eb's. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 0ce14369..4a97d8f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3683,6 +3683,17 @@
__free_extent_buffer(eb);
}
+static void mark_extent_buffer_accessed(struct extent_buffer *eb)
+{
+ unsigned long num_pages, i;
+
+ num_pages = num_extent_pages(eb->start, eb->len);
+ for (i = 0; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+ mark_page_accessed(p);
+ }
+}
+
struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
u64 start, unsigned long len)
{
@@ -3700,7 +3711,7 @@
eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
if (eb && atomic_inc_not_zero(&eb->refs)) {
rcu_read_unlock();
- mark_page_accessed(eb->pages[0]);
+ mark_extent_buffer_accessed(eb);
return eb;
}
rcu_read_unlock();
@@ -3729,6 +3740,7 @@
if (atomic_inc_not_zero(&exists->refs)) {
spin_unlock(&mapping->private_lock);
unlock_page(p);
+ mark_extent_buffer_accessed(exists);
goto free_eb;
}
@@ -3771,6 +3783,7 @@
}
spin_unlock(&tree->buffer_lock);
radix_tree_preload_end();
+ mark_extent_buffer_accessed(exists);
goto free_eb;
}
/* add one reference for the tree */
@@ -3820,7 +3833,7 @@
eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
if (eb && atomic_inc_not_zero(&eb->refs)) {
rcu_read_unlock();
- mark_page_accessed(eb->pages[0]);
+ mark_extent_buffer_accessed(eb);
return eb;
}
rcu_read_unlock();