For what it's worth, another positive report on this patch: https://bugzilla.kernel.org/show_bug.cgi?id=213869#c10 --b. On Mon, Aug 30, 2021 at 08:36:34AM +1000, NeilBrown wrote: > > alloc_pages_bulk_array() attempts to allocate at least one page based on > the provided pages, and then opportunistically allocates more if that > can be done without dropping the spinlock. > > So if it returns fewer than requested, that could just mean that it > needed to drop the lock. In that case, try again immediately. > > Only pause for a time if no progress could be made. > > Reported-and-tested-by: Mike Javorski <mike.javorski@xxxxxxxxx> > Reported-and-tested-by: Lothar Paltins <lopa@xxxxxxxxxxx> > Fixes: f6e70aab9dfe ("SUNRPC: refresh rq_pages using a bulk page allocator") > Signed-off-by: NeilBrown <neilb@xxxxxxx> > --- > > I decided I would resend, as I thought the for() loops could be clearer. > This patch should perform exactly the same as the previous one. > > > net/sunrpc/svc_xprt.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c > index d66a8e44a1ae..e74d5cf3cbb4 100644 > --- a/net/sunrpc/svc_xprt.c > +++ b/net/sunrpc/svc_xprt.c > @@ -662,7 +662,7 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) > { > struct svc_serv *serv = rqstp->rq_server; > struct xdr_buf *arg = &rqstp->rq_arg; > - unsigned long pages, filled; > + unsigned long pages, filled, ret; > > pages = (serv->sv_max_mesg + 2 * PAGE_SIZE) >> PAGE_SHIFT; > if (pages > RPCSVC_MAXPAGES) { > @@ -672,11 +672,12 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) > pages = RPCSVC_MAXPAGES; > } > > - for (;;) { > - filled = alloc_pages_bulk_array(GFP_KERNEL, pages, > - rqstp->rq_pages); > - if (filled == pages) > - break; > + for (filled = 0; filled < pages; filled = ret) { > + ret = alloc_pages_bulk_array(GFP_KERNEL, pages, > + rqstp->rq_pages); > + if (ret > filled) > + /* Made progress, don't sleep yet */ > + continue; > > set_current_state(TASK_INTERRUPTIBLE); > if (signalled() || kthread_should_stop()) { > -- > 2.32.0
