linux-kernel - [PATCH 2/3] iomap: Use bitmap ops to set uptodate bits

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Date:   Fri, 21 Aug 2020 13:46:05 +0100
From:   "Matthew Wilcox (Oracle)" <willy@...radead.org>
To:     Yu Kuai <yukuai3@...wei.com>, hch@...radead.org,
        darrick.wong@...cle.com, david@...morbit.com,
        linux-xfs@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-kernel@...r.kernel.org, yi.zhang@...wei.com
Cc:     "Matthew Wilcox (Oracle)" <willy@...radead.org>
Subject: [PATCH 2/3] iomap: Use bitmap ops to set uptodate bits

Now that the bitmap is protected by a spinlock, we can use the
more efficient bitmap ops instead of individual test/set bit ops.

Signed-off-by: Matthew Wilcox (Oracle) <willy@...radead.org>
---
 fs/iomap/buffered-io.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 639d54a4177e..dbf9572dabe9 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -134,19 +134,11 @@ iomap_iop_set_range_uptodate(struct page *page, unsigned off, unsigned len)
 	struct inode *inode = page->mapping->host;
 	unsigned first = off >> inode->i_blkbits;
 	unsigned last = (off + len - 1) >> inode->i_blkbits;
-	bool uptodate = true;
 	unsigned long flags;
-	unsigned int i;
 
 	spin_lock_irqsave(&iop->uptodate_lock, flags);
-	for (i = 0; i < i_blocks_per_page(inode, page); i++) {
-		if (i >= first && i <= last)
-			set_bit(i, iop->uptodate);
-		else if (!test_bit(i, iop->uptodate))
-			uptodate = false;
-	}
-
-	if (uptodate)
+	bitmap_set(iop->uptodate, first, last - first + 1);
+	if (bitmap_full(iop->uptodate, i_blocks_per_page(inode, page)))
 		SetPageUptodate(page);
 	spin_unlock_irqrestore(&iop->uptodate_lock, flags);
 }
-- 
2.28.0