Re: [PATCH v5 5/5] fuse: remove tmp folio for writebacks and internal rb tree

[Jingbo Xu <jefflexu@linux.alibaba.com>]

On 11/16/24 6:44 AM, Joanne Koong wrote:




> @@ -1838,7 +1748,7 @@ static void fuse_writepage_finish_stat(struct inode *inode, struct folio *folio)
>  	struct backing_dev_info *bdi = inode_to_bdi(inode);
>  
>  	dec_wb_stat(&bdi->wb, WB_WRITEBACK);
> -	node_stat_sub_folio(folio, NR_WRITEBACK_TEMP);
> +	node_stat_sub_folio(folio, NR_WRITEBACK);

Now fuse_writepage_finish_stat() has only one caller and we could make
it embedded into its only caller.


>  static void fuse_writepage_args_page_fill(struct fuse_writepage_args *wpa, struct folio *folio,
> -					  struct folio *tmp_folio, uint32_t folio_index)
> +					  uint32_t folio_index)
>  {
>  	struct inode *inode = folio->mapping->host;
>  	struct fuse_args_pages *ap = &wpa->ia.ap;
>  
> -	folio_copy(tmp_folio, folio);
> -
> -	ap->folios[folio_index] = tmp_folio;
> +	ap->folios[folio_index] = folio;
>  	ap->descs[folio_index].offset = 0;
>  	ap->descs[folio_index].length = PAGE_SIZE;
>  
>  	inc_wb_stat(&inode_to_bdi(inode)->wb, WB_WRITEBACK);
> -	node_stat_add_folio(tmp_folio, NR_WRITEBACK_TEMP);
> +	node_stat_add_folio(folio, NR_WRITEBACK);

This inc NR_WRITEBACK counter along with the corresponding dec
NR_WRITEBACK counter in fuse_writepage_finish_stat() seems unnecessary,
as folio_start_writeback() will increase the NR_WRITEBACK counter, while
folio_end_writeback() will decrease the NR_WRITEBACK counter.





-- 
Thanks,
Jingbo