Commit 6a0cdf56 authored by Chuck Lever's avatar Chuck Lever
Browse files

SUNRPC: Be even lazier about releasing pages 



A single RPC transaction that touches only a couple of pages means
rq_pvec will not be even close to full in svc_xpt_release(). This is
a common case.

Instead, just leave the pages in rq_pvec until it is completely
full. This improves the efficiency of the batch release mechanism
on workloads that involve small RPC messages.

The rq_pvec is also fully emptied just before thread exit.

Reviewed-by: default avatarCalum Mackay <calum.mackay@oracle.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 647a2a64

net/sunrpc/svc.c

+3 −0
Original line number Diff line number Diff line
@@ -649,6 +649,8 @@ svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node) 
	if (!rqstp)

		return rqstp;



	pagevec_init(&rqstp->rq_pvec);



	__set_bit(RQ_BUSY, &rqstp->rq_flags);

	rqstp->rq_server = serv;

	rqstp->rq_pool = pool;
@@ -894,6 +896,7 @@ void svc_rqst_release_pages(struct svc_rqst *rqstp) 
void

svc_rqst_free(struct svc_rqst *rqstp)

{

	pagevec_release(&rqstp->rq_pvec);

	svc_release_buffer(rqstp);

	if (rqstp->rq_scratch_page)

		put_page(rqstp->rq_scratch_page);

net/sunrpc/svc_xprt.c

+0 −3
Original line number Diff line number Diff line
@@ -541,7 +541,6 @@ static void svc_xprt_release(struct svc_rqst *rqstp) 
	kfree(rqstp->rq_deferred);

	rqstp->rq_deferred = NULL;



	pagevec_release(&rqstp->rq_pvec);

	svc_rqst_release_pages(rqstp);

	rqstp->rq_res.page_len = 0;

	rqstp->rq_res.page_base = 0;
@@ -667,8 +666,6 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) 
	struct xdr_buf *arg = &rqstp->rq_arg;

	unsigned long pages, filled, ret;



	pagevec_init(&rqstp->rq_pvec);



	pages = (serv->sv_max_mesg + 2 * PAGE_SIZE) >> PAGE_SHIFT;

	if (pages > RPCSVC_MAXPAGES) {

		pr_warn_once("svc: warning: pages=%lu > RPCSVC_MAXPAGES=%lu\n",