Re: [PATCH 2/3] iomap: Use bitmap ops to set uptodate bits

From: Christoph Hellwig
Date: Sat Aug 22 2020 - 02:00:05 EST


On Fri, Aug 21, 2020 at 01:46:05PM +0100, Matthew Wilcox (Oracle) wrote:
> 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@xxxxxxxxxxxxx>
> ---
> 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);

Can you respin this to be based on current Linus' tree without
i_blocks_per_page? With that it looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>