[PATCH RFC 4/8] Set WQ_SYSFS on key NFS-related workqueues

[Chuck Lever <cel@kernel.org>]

WQ_SYSFS exposes settable workqueue attributes under
/sys/devices/virtual/workqueue/. For NFS workloads, this is useful
for tuning affinity scope at runtime without reloading modules.

Signed-off-by: Chuck Lever <cel@kernel.org>
---
 fs/nfs/inode.c     | 3 ++-
 net/sunrpc/sched.c | 5 +++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 3022454f7698..107a2135029d 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -2619,7 +2619,8 @@ static void nfsiod_stop(void)
 static int nfsiod_start(void)
 {
 	dprintk("RPC:       creating workqueue nfsiod\n");
-	nfsiod_workqueue = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
+	nfsiod_workqueue = alloc_workqueue("nfsiod",
+				WQ_MEM_RECLAIM | WQ_UNBOUND | WQ_SYSFS, 0);
 	if (nfsiod_workqueue == NULL)
 		return -ENOMEM;
 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 9b2800f6bfc7..c31cf55b933f 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -1271,16 +1271,17 @@ void rpciod_down(void)
  */
 static int rpciod_start(void)
 {
+	const unsigned int wq_flags = WQ_MEM_RECLAIM | WQ_UNBOUND | WQ_SYSFS;
 	struct workqueue_struct *wq;
 
 	/*
 	 * Create the rpciod thread and wait for it to start.
 	 */
-	wq = alloc_workqueue("rpciod", WQ_MEM_RECLAIM | WQ_UNBOUND, 0);
+	wq = alloc_workqueue("rpciod", wq_flags, 0);
 	if (!wq)
 		goto out_failed;
 	rpciod_workqueue = wq;
-	wq = alloc_workqueue("xprtiod", WQ_UNBOUND | WQ_MEM_RECLAIM, 0);
+	wq = alloc_workqueue("xprtiod", wq_flags, 0);
 	if (!wq)
 		goto free_rpciod;
 	xprtiod_workqueue = wq;

-- 
2.55.0