Thread (67 messages) 67 messages, 4 authors, 2017-02-13

Re: [PATCHv6 13/37] mm: make write_cache_pages() work on huge pages

From: Matthew Wilcox <willy@infradead.org>
Date: 2017-02-10 17:46:10
Also in: linux-block, linux-fsdevel, linux-mm, lkml

On Thu, Jan 26, 2017 at 02:57:55PM +0300, Kirill A. Shutemov wrote:
We writeback whole huge page a time. Let's adjust iteration this way.

Signed-off-by: Kirill A. Shutemov <redacted>
I think a lot of the complexity in this patch is from pagevec_lookup_tag
giving you subpages rather than head pages...
quoted hunk ↗ jump to hunk
@@ -2268,7 +2273,8 @@ int write_cache_pages(struct address_space *mapping,
 					 * not be suitable for data integrity
 					 * writeout).
 					 */
-					done_index = page->index + 1;
+					done_index = compound_head(page)->index
+						+ hpage_nr_pages(page);
 					done = 1;
 					break;
 				}
you'd still need this line, but it'd only be:

					done_index = page->index +
						(1 << compound_order(page));

I think we want:

#define	nr_pages(page)	(1 << compound_order(page))

because we seem to be repeating that idiom quite a lot in these patches.

					done_index = page->index +
								nr_pages(page);

Still doesn't quite fit on one line, but it's closer, and it's the
ridiculous indentation in that function that's the real problem.

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help