mm: cleanup add_to_page_cache_locked()
Make add_to_page_cache_locked() cleaner:
- unindent most code of the function by inverting one condition;
- streamline code no-error path;
- move insert error path outside normal code path;
- call radix_tree_preload_end() earlier;
No functional changes.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Hugh Dickins <hughd@google.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/filemap.c b/mm/filemap.c
index e3b6fc8c..1e6aec4 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -467,32 +467,34 @@
error = mem_cgroup_cache_charge(page, current->mm,
gfp_mask & GFP_RECLAIM_MASK);
if (error)
- goto out;
+ return error;
error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM);
- if (error == 0) {
- page_cache_get(page);
- page->mapping = mapping;
- page->index = offset;
-
- spin_lock_irq(&mapping->tree_lock);
- error = radix_tree_insert(&mapping->page_tree, offset, page);
- if (likely(!error)) {
- mapping->nrpages++;
- __inc_zone_page_state(page, NR_FILE_PAGES);
- spin_unlock_irq(&mapping->tree_lock);
- trace_mm_filemap_add_to_page_cache(page);
- } else {
- page->mapping = NULL;
- /* Leave page->index set: truncation relies upon it */
- spin_unlock_irq(&mapping->tree_lock);
- mem_cgroup_uncharge_cache_page(page);
- page_cache_release(page);
- }
- radix_tree_preload_end();
- } else
+ if (error) {
mem_cgroup_uncharge_cache_page(page);
-out:
+ return error;
+ }
+
+ page_cache_get(page);
+ page->mapping = mapping;
+ page->index = offset;
+
+ spin_lock_irq(&mapping->tree_lock);
+ error = radix_tree_insert(&mapping->page_tree, offset, page);
+ radix_tree_preload_end();
+ if (unlikely(error))
+ goto err_insert;
+ mapping->nrpages++;
+ __inc_zone_page_state(page, NR_FILE_PAGES);
+ spin_unlock_irq(&mapping->tree_lock);
+ trace_mm_filemap_add_to_page_cache(page);
+ return 0;
+err_insert:
+ page->mapping = NULL;
+ /* Leave page->index set: truncation relies upon it */
+ spin_unlock_irq(&mapping->tree_lock);
+ mem_cgroup_uncharge_cache_page(page);
+ page_cache_release(page);
return error;
}
EXPORT_SYMBOL(add_to_page_cache_locked);