From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Mon, 18 Dec 2017 19:39:13 +0000 (-0500)
Subject: NFS: Add a cond_resched() to nfs_commit_release_pages()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3d03af006438b91dab7c1feb474a5c899554acac;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

NFS: Add a cond_resched() to nfs_commit_release_pages()

commit 7f1bda447c9bd48b415acedba6b830f61591601f upstream.

The commit list can get very large, and so we need a cond_resched()
in nfs_commit_release_pages() in order to ensure we don't hog the CPU
for excessive periods of time.

Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index de325804941d..76da415be39a 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1836,6 +1836,8 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data)
 		set_bit(NFS_CONTEXT_RESEND_WRITES, &req->wb_context->flags);
 	next:
 		nfs_unlock_and_release_request(req);
+		/* Latency breaker */
+		cond_resched();
 	}
 	nfss = NFS_SERVER(data->inode);
 	if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)