From 085804110aa13eac7f763d8d5cfe3a8220e35222 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Fri, 15 Nov 2024 20:41:02 -0500 Subject: nfs_common: track all open nfsd_files per LOCALIO nfs_client This tracking enables __nfsd_file_cache_purge() to call nfs_localio_invalidate_clients(), upon shutdown or export change, to nfs_close_local_fh() all open nfsd_files that are still cached by the LOCALIO nfs clients associated with nfsd_net that is being shutdown. Now that the client must track all open nfsd_files there was more work than necessary being done with the global nfs_uuids_lock contended. This manifested in various RCU issues, e.g.: hrtimer: interrupt took 47969440 ns rcu: INFO: rcu_sched detected stalls on CPUs/tasks: Use nfs_uuid->lock to protect all nfs_uuid_t members, instead of nfs_uuids_lock, once nfs_uuid_is_local() adds the client to nn->local_clients. Also add 'local_clients_lock' to 'struct nfsd_net' to protect nn->local_clients. And store a pointer to spinlock in the 'list_lock' member of nfs_uuid_t so nfs_localio_disable_client() can use it to avoid taking the global nfs_uuids_lock. In combination, these split out locks eliminate the use of the single nfslocalio.c global nfs_uuids_lock in the IO paths (open and close). Also refactored associated fs/nfs_common/nfslocalio.c methods' locking to reduce work performed with spinlocks held in general. Signed-off-by: Mike Snitzer Reviewed-by: Jeff Layton Signed-off-by: Anna Schumaker --- include/linux/nfslocalio.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/nfslocalio.h b/include/linux/nfslocalio.h index aa2b5c6561ab..c68a529230c1 100644 --- a/include/linux/nfslocalio.h +++ b/include/linux/nfslocalio.h @@ -30,19 +30,23 @@ typedef struct { /* sadly this struct is just over a cacheline, avoid bouncing */ spinlock_t ____cacheline_aligned lock; struct list_head list; + spinlock_t *list_lock; /* nn->local_clients_lock */ struct net __rcu *net; /* nfsd's network namespace */ struct auth_domain *dom; /* auth_domain for localio */ + /* Local files to close when net is shut down or exports change */ + struct list_head files; } nfs_uuid_t; void nfs_uuid_init(nfs_uuid_t *); bool nfs_uuid_begin(nfs_uuid_t *); void nfs_uuid_end(nfs_uuid_t *); -void nfs_uuid_is_local(const uuid_t *, struct list_head *, +void nfs_uuid_is_local(const uuid_t *, struct list_head *, spinlock_t *, struct net *, struct auth_domain *, struct module *); void nfs_localio_enable_client(struct nfs_client *clp); void nfs_localio_disable_client(struct nfs_client *clp); -void nfs_localio_invalidate_clients(struct list_head *list); +void nfs_localio_invalidate_clients(struct list_head *nn_local_clients, + spinlock_t *nn_local_clients_lock); /* localio needs to map filehandle -> struct nfsd_file */ extern struct nfsd_file * -- cgit v1.2.3