Move checks and accounting updates from __delete_from_page_cache() into
a separate function. We will reuse it when batching page cache
truncation operations.
Acked-by: Mel Gorman <mgorman@xxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
mm/filemap.c | 72 ++++++++++++++++++++++++++++++++++--------------------------
1 file changed, 41 insertions(+), 31 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index c866a84bd45c..6fb01b2404a7 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -181,17 +181,11 @@ static void page_cache_tree_delete(struct address_space *mapping,
mapping->nrpages -= nr;
}
-/*
- * Delete a page from the page cache and free it. Caller has to make
- * sure the page is locked and that nobody else uses it - or that usage
- * is safe. The caller must hold the mapping's tree_lock.
- */
-void __delete_from_page_cache(struct page *page, void *shadow)
+static void unaccount_page_cache_page(struct address_space *mapping,
+ struct page *page)
{
- struct address_space *mapping = page->mapping;
- int nr = hpage_nr_pages(page);
+ int nr;
- trace_mm_filemap_delete_from_page_cache(page);
/*
* if we're uptodate, flush out into the cleancache, otherwise
* invalidate any existing cleancache entries. We can't leave
@@ -228,30 +222,46 @@ void __delete_from_page_cache(struct page *page, void *shadow)
}
/* hugetlb pages do not participate in page cache accounting. */
- if (!PageHuge(page)) {
- __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, -nr);
- if (PageSwapBacked(page)) {
- __mod_node_page_state(page_pgdat(page), NR_SHMEM, -nr);
- if (PageTransHuge(page))
- __dec_node_page_state(page, NR_SHMEM_THPS);
- } else {
- VM_BUG_ON_PAGE(PageTransHuge(page), page);
- }
+ if (PageHuge(page))
+ return;
- /*
- * At this point page must be either written or cleaned by
- * truncate. Dirty page here signals a bug and loss of
- * unwritten data.
- *
- * This fixes dirty accounting after removing the page entirely
- * but leaves PageDirty set: it has no effect for truncated
- * page and anyway will be cleared before returning page into
- * buddy allocator.
- */
- if (WARN_ON_ONCE(PageDirty(page)))
- account_page_cleaned(page, mapping,
- inode_to_wb(mapping->host));
+ nr = hpage_nr_pages(page);
+
+ __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, -nr);
+ if (PageSwapBacked(page)) {
+ __mod_node_page_state(page_pgdat(page), NR_SHMEM, -nr);
+ if (PageTransHuge(page))
+ __dec_node_page_state(page, NR_SHMEM_THPS);
+ } else {
+ VM_BUG_ON_PAGE(PageTransHuge(page), page);
}
+
+ /*
+ * At this point page must be either written or cleaned by
+ * truncate. Dirty page here signals a bug and loss of
+ * unwritten data.
+ *
+ * This fixes dirty accounting after removing the page entirely
+ * but leaves PageDirty set: it has no effect for truncated
+ * page and anyway will be cleared before returning page into
+ * buddy allocator.
+ */
+ if (WARN_ON_ONCE(PageDirty(page)))
+ account_page_cleaned(page, mapping, inode_to_wb(mapping->host));
+}
+
+/*
+ * Delete a page from the page cache and free it. Caller has to make
+ * sure the page is locked and that nobody else uses it - or that usage
+ * is safe. The caller must hold the mapping's tree_lock.
+ */
+void __delete_from_page_cache(struct page *page, void *shadow)
+{
+ struct address_space *mapping = page->mapping;
+
+ trace_mm_filemap_delete_from_page_cache(page);
+
+ unaccount_page_cache_page(mapping, page);
page_cache_tree_delete(mapping, page, shadow);
}
--
2.12.3
