mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-02 09:40:27 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

ext4: pipeline buffer reads in mext_page_mkuptodate()

Browse source 
Instead of synchronously reading one buffer at a time, submit reads
as we walk the buffers in the first loop, then wait for them in the
second loop.  This should be significantly more efficient, particularly
on HDDs, but I have not measured.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://patch.msgid.link/20240718223005.568869-2-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Matthew Wilcox (Oracle) 2024-07-18 23:30:00 +01:00 committed by Theodore Ts'o
parent e37c9e173b
commit 368a83cebb
1 changed files with 15 additions and 8 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

23
fs/ext4/move_extent.c
View file

@ -174,7 +174,9 @@ mext_page_mkuptodate(struct folio *folio, unsigned from, unsigned to)
sector_t block;
struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
unsigned int blocksize, block_start, block_end;
int i, err, nr = 0, partial = 0;
int i, nr = 0;
bool partial = false;
BUG_ON(!folio_test_locked(folio));
BUG_ON(folio_test_writeback(folio));
@ -192,13 +194,13 @@ mext_page_mkuptodate(struct folio *folio, unsigned from, unsigned to)
block_end = block_start + blocksize;
if (block_end <= from || block_start >= to) {
if (!buffer_uptodate(bh))
partial = 1;
partial = true;
continue;
}
if (buffer_uptodate(bh))
continue;
if (!buffer_mapped(bh)) {
err = ext4_get_block(inode, block, bh, 0);
int err = ext4_get_block(inode, block, bh, 0);
if (err)
return err;
if (!buffer_mapped(bh)) {
@ -207,6 +209,12 @@ mext_page_mkuptodate(struct folio *folio, unsigned from, unsigned to)
continue;
}
}
lock_buffer(bh);
if (buffer_uptodate(bh)) {
unlock_buffer(bh);
continue;
}
ext4_read_bh_nowait(bh, 0, NULL);
BUG_ON(nr >= MAX_BUF_PER_PAGE);
arr[nr++] = bh;
}
@ -216,11 +224,10 @@ mext_page_mkuptodate(struct folio *folio, unsigned from, unsigned to)
for (i = 0; i < nr; i++) {
bh = arr[i];
if (!bh_uptodate_or_lock(bh)) {
err = ext4_read_bh(bh, 0, NULL);
if (err)
return err;
}
wait_on_buffer(bh);
if (buffer_uptodate(bh))
continue;
return -EIO;
}
out:
if (!partial)