Re: [PATCH] netfs: Fault in smaller chunks for non-large folio mappings

[Matthew Wilcox <willy@infradead.org>]

On Mon, May 27, 2024 at 09:17:32PM +0100, Matthew Wilcox (Oracle) wrote:
> As in commit 4e527d5841e2 ("iomap: fault in smaller chunks for non-large
> folio mappings"), we can see a performance loss for filesystems
> which have not yet been converted to large folios.

Did this patch get lost?

> Fixes: c38f4e96e605 ("netfs: Provide func to copy data to pagecache for buffered write")
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
>  fs/netfs/buffered_write.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/netfs/buffered_write.c b/fs/netfs/buffered_write.c
> index 07bc1fd43530..3288561e98dd 100644
> --- a/fs/netfs/buffered_write.c
> +++ b/fs/netfs/buffered_write.c
> @@ -184,7 +184,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
>  	unsigned int bdp_flags = (iocb->ki_flags & IOCB_NOWAIT) ? BDP_ASYNC : 0;
>  	ssize_t written = 0, ret, ret2;
>  	loff_t i_size, pos = iocb->ki_pos, from, to;
> -	size_t max_chunk = PAGE_SIZE << MAX_PAGECACHE_ORDER;
> +	size_t max_chunk = mapping_max_folio_size(mapping);
>  	bool maybe_trouble = false;
>  
>  	if (unlikely(test_bit(NETFS_ICTX_WRITETHROUGH, &ctx->flags) ||
> -- 
> 2.43.0
>