diff mbox series

[7/8] erofs: adapt folios for z_erofs_readahead()

Message ID 20230817082813.81180-7-hsiangkao@linux.alibaba.com
State New
Headers
Series [1/8] erofs: simplify z_erofs_read_fragment() |

Commit Message

Gao Xiang Aug. 17, 2023, 8:28 a.m. UTC 
  It's a straight-forward conversion except that readahead_folio()
will do folio_put() in advance but it doesn't matter since folios
are still locked.

As before, since file-backed folios (pages for now) are locked, so
we could temporarily use folio->private as an internal counter to
indicate split parts of each folio for the corresponding pclusters
to decompress.

When such counter becomes zero, the folio will be finally unlocked
(see compress.h and z_erofs_onlinepage_endio()).

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
 fs/erofs/zdata.c | 32 +++++++++++++++-----------------
 1 file changed, 15 insertions(+), 17 deletions(-)

Comments

Chao Yu Aug. 23, 2023, 3:22 p.m. UTC | #1 
On 2023/8/17 16:28, Gao Xiang wrote:
> It's a straight-forward conversion except that readahead_folio()
> will do folio_put() in advance but it doesn't matter since folios
> are still locked.
> 
> As before, since file-backed folios (pages for now) are locked, so
> we could temporarily use folio->private as an internal counter to
> indicate split parts of each folio for the corresponding pclusters
> to decompress.
> 
> When such counter becomes zero, the folio will be finally unlocked
> (see compress.h and z_erofs_onlinepage_endio()).
> 
> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,
diff mbox series

Patch

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index c28945532a02..79cadb88e8bf 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1852,37 +1852,35 @@  static void z_erofs_readahead(struct readahead_control *rac)
 	struct inode *const inode = rac->mapping->host;
 	struct erofs_sb_info *const sbi = EROFS_I_SB(inode);
 	struct z_erofs_decompress_frontend f = DECOMPRESS_FRONTEND_INIT(inode);
-	struct page *head = NULL, *page;
-	unsigned int nr_pages;
+	struct folio *head = NULL, *folio;
+	unsigned int nr_folios;
+	int err;
 
 	f.headoffset = readahead_pos(rac);
 
 	z_erofs_pcluster_readmore(&f, rac, true);
-	nr_pages = readahead_count(rac);
-	trace_erofs_readpages(inode, readahead_index(rac), nr_pages, false);
+	nr_folios = readahead_count(rac);
+	trace_erofs_readpages(inode, readahead_index(rac), nr_folios, false);
 
-	while ((page = readahead_page(rac))) {
-		set_page_private(page, (unsigned long)head);
-		head = page;
+	while ((folio = readahead_folio(rac))) {
+		folio->private = head;
+		head = folio;
 	}
 
+	/* traverse in reverse order for best metadata I/O performance */
 	while (head) {
-		struct page *page = head;
-		int err;
-
-		/* traversal in reverse order */
-		head = (void *)page_private(page);
+		folio = head;
+		head = folio_get_private(folio);
 
-		err = z_erofs_do_read_page(&f, page);
+		err = z_erofs_do_read_page(&f, &folio->page);
 		if (err && err != -EINTR)
-			erofs_err(inode->i_sb, "readahead error %d @ %lu of nid %llu",
-				  err, page->index, EROFS_I(inode)->nid);
-		put_page(page);
+			erofs_err(inode->i_sb, "readahead error at folio %lu @ nid %llu",
+				  folio->index, EROFS_I(inode)->nid);
 	}
 	z_erofs_pcluster_readmore(&f, rac, false);
 	z_erofs_pcluster_end(&f);
 
-	z_erofs_runqueue(&f, z_erofs_is_sync_decompress(sbi, nr_pages), true);
+	z_erofs_runqueue(&f, z_erofs_is_sync_decompress(sbi, nr_folios), true);
 	erofs_put_metabuf(&f.map.buf);
 	erofs_release_pages(&f.pagepool);
 }