Re: [PATCH 09/13] net: Convert sunrpc from pagevec to folio_batch

[Chuck Lever]

On Wed, Jun 21, 2023 at 05:45:53PM +0100, Matthew Wilcox (Oracle) wrote:
> Remove the last usage of pagevecs.  There is a slight change here; we
> now free the folio_batch as soon as it fills up instead of freeing the
> folio_batch when we try to add a page to a full batch.  This should have
> no effect in practice.
> 
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>

I don't yet have visibility into the folio_batch_* helpers, but this
looks like a wholly mechanical replacement of pagevec. LGTM.

I assume this is going to be merged via another tree, not nfsd-next,
so:

Acked-by: Chuck Lever <chuck.lever@xxxxxxxxxx>


> ---
>  include/linux/sunrpc/svc.h |  2 +-
>  net/sunrpc/svc.c           | 10 +++++-----
>  2 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
> index c2807e301790..f8751118c122 100644
> --- a/include/linux/sunrpc/svc.h
> +++ b/include/linux/sunrpc/svc.h
> @@ -222,7 +222,7 @@ struct svc_rqst {
>  	struct page *		*rq_next_page; /* next reply page to use */
>  	struct page *		*rq_page_end;  /* one past the last page */
>  
> -	struct pagevec		rq_pvec;
> +	struct folio_batch	rq_fbatch;
>  	struct kvec		rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */
>  	struct bio_vec		rq_bvec[RPCSVC_MAXPAGES];
>  
> diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
> index e7c101290425..587811a002c9 100644
> --- a/net/sunrpc/svc.c
> +++ b/net/sunrpc/svc.c
> @@ -640,7 +640,7 @@ svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node)
>  	if (!rqstp)
>  		return rqstp;
>  
> -	pagevec_init(&rqstp->rq_pvec);
> +	folio_batch_init(&rqstp->rq_fbatch);
>  
>  	__set_bit(RQ_BUSY, &rqstp->rq_flags);
>  	rqstp->rq_server = serv;
> @@ -851,9 +851,9 @@ bool svc_rqst_replace_page(struct svc_rqst *rqstp, struct page *page)
>  	}
>  
>  	if (*rqstp->rq_next_page) {
> -		if (!pagevec_space(&rqstp->rq_pvec))
> -			__pagevec_release(&rqstp->rq_pvec);
> -		pagevec_add(&rqstp->rq_pvec, *rqstp->rq_next_page);
> +		if (!folio_batch_add(&rqstp->rq_fbatch,
> +				page_folio(*rqstp->rq_next_page)))
> +			__folio_batch_release(&rqstp->rq_fbatch);
>  	}
>  
>  	get_page(page);
> @@ -887,7 +887,7 @@ void svc_rqst_release_pages(struct svc_rqst *rqstp)
>  void
>  svc_rqst_free(struct svc_rqst *rqstp)
>  {
> -	pagevec_release(&rqstp->rq_pvec);
> +	folio_batch_release(&rqstp->rq_fbatch);
>  	svc_release_buffer(rqstp);
>  	if (rqstp->rq_scratch_page)
>  		put_page(rqstp->rq_scratch_page);
> -- 
> 2.39.2
>