Commit 6981b468 authored by NeilBrown's avatar NeilBrown Committed by ZhaoLong Wang
Browse files

SUNRPC: don't pause on incomplete allocation 

mainline inclusion
from mainline-v5.15-rc1
commit e38b3f20
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7RRY4
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e38b3f20059426a0adbde014ff71071739ab5226



-------------------------------------------------

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: default avatarMike Javorski <mike.javorski@gmail.com>
Reported-and-tested-by: default avatarLothar Paltins <lopa@mailbox.org>
Fixes: f6e70aab ("SUNRPC: refresh rq_pages using a bulk page allocator")
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Acked-by: default avatarMel Gorman <mgorman@suse.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarZhaoLong Wang <wangzhaolong1@huawei.com>

Conflicts:
    net/sunrpc/svc_xprt.c
parent 829ecc1d

net/sunrpc/svc_xprt.c

+7 −6
Original line number Diff line number Diff line
@@ -643,7 +643,7 @@ 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) {
@@ -653,11 +653,12 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) 
		pages = RPCSVC_MAXPAGES;

	}



	for (;;) {

		filled = alloc_pages_bulk_array(GFP_KERNEL, pages,

	for (filled = 0; filled < pages; filled = ret) {

		ret = alloc_pages_bulk_array(GFP_KERNEL, pages,

					     rqstp->rq_pages);

		if (filled == pages)

			break;

		if (ret > filled)

			/* Made progress, don't sleep yet */

			continue;



		set_current_state(TASK_INTERRUPTIBLE);

		if (signalled() || kthread_should_stop()) {