Instead of invoking put_page() one-at-a-time, pass the "response"
portion of rq_pages directly to release_pages() to reduce the number
of times each nfsd thread invokes a page allocator API.
Since svc_xprt_release() is not invoked while a client is waiting
for an RPC Reply, this is not expected to directly impact mean
request latencies on a lightly or moderately loaded server. However
as workload intensity increases, I expect somewhat better
scalability: the same number of server threads should be able to
handle more work.
Reviewed-by: Calum Mackay <calum.mackay@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
*/
void svc_rqst_release_pages(struct svc_rqst *rqstp)
{
- while (rqstp->rq_next_page != rqstp->rq_respages) {
- struct page **pp = --rqstp->rq_next_page;
+ int i, count = rqstp->rq_next_page - rqstp->rq_respages;
- if (*pp) {
- put_page(*pp);
- *pp = NULL;
- }
+ if (count) {
+ release_pages(rqstp->rq_respages, count);
+ for (i = 0; i < count; i++)
+ rqstp->rq_respages[i] = NULL;
}
}