block_write_full_page: Use synchronous writes for WBC_SYNC_ALL writebacks

When doing synchronous writes because wbc->sync_mode is set to
WBC_SYNC_ALL, send the write request using WRITE_SYNC, so that we
don't unduly block system calls such as fsync().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Theodore Ts'o 2009-03-27 22:14:10 -04:00
parent 8e0ee43bc2
commit a64c8610bd

View file

@ -1714,6 +1714,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page,
struct buffer_head *bh, *head;
const unsigned blocksize = 1 << inode->i_blkbits;
int nr_underway = 0;
int write_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE);
BUG_ON(!PageLocked(page));
@ -1805,7 +1806,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page,
do {
struct buffer_head *next = bh->b_this_page;
if (buffer_async_write(bh)) {
submit_bh(WRITE, bh);
submit_bh(write_op, bh);
nr_underway++;
}
bh = next;
@ -1859,7 +1860,7 @@ recover:
struct buffer_head *next = bh->b_this_page;
if (buffer_async_write(bh)) {
clear_buffer_dirty(bh);
submit_bh(WRITE, bh);
submit_bh(write_op, bh);
nr_underway++;
}
bh = next;