Commit 1bce63d1 authored by Shaohua Li's avatar Shaohua Li Committed by Theodore Ts'o
Browse files

ext4: add block plug for .writepages 



Add block plug for ext4 .writepages. Though ext4 .writepages
already handles request merge very well, block plug is still
helpful to reduce block lock contention.

Signed-off-by: default avatarShaohua Li <shaohua.li@intel.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent f6f96fdb

fs/ext4/inode.c

+3 −0
Original line number Diff line number Diff line
@@ -2160,6 +2160,7 @@ static int ext4_da_writepages(struct address_space *mapping, 
	struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);

	pgoff_t done_index = 0;

	pgoff_t end;

	struct blk_plug plug;



	trace_ext4_da_writepages(inode, wbc);
@@ -2238,6 +2239,7 @@ retry: 
	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)

		tag_pages_for_writeback(mapping, index, end);



	blk_start_plug(&plug);

	while (!ret && wbc->nr_to_write > 0) {



		/*
@@ -2302,6 +2304,7 @@ retry: 
			 */

			break;

	}

	blk_finish_plug(&plug);

	if (!io_done && !cycled) {

		cycled = 1;

		index = 0;