[PATCH 09/11] nfs: add memory barrier before calling wake_up_var on cl_state
From: NeilBrown <hidden>
Date: 2024-12-06 02:19:52
Subsystem:
filesystems (vfs and infrastructure), nfs, sunrpc, and lockd clients, the rest · Maintainers:
Alexander Viro, Christian Brauner, Trond Myklebust, Anna Schumaker, Linus Torvalds
After setting NFS4CLNT_RUN_MANAGER we need a full memory barrier before it is safe to call wake_up_var(). As that setting is "atomic" it is sufficient to use smp_mb__after_atomic(). Signed-off-by: NeilBrown <redacted> --- fs/nfs/nfs4proc.c | 1 + fs/nfs/nfs4state.c | 1 + 2 files changed, 2 insertions(+)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 405f17e6e0b4..37c8aa1f3e1b 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c@@ -10847,6 +10847,7 @@ static void nfs4_disable_swap(struct inode *inode) set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state); clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); + smp_mb__after_atomic(); wake_up_var(&clp->cl_state); }
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 556b521f17eb..189d7b57cb74 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c@@ -1207,6 +1207,7 @@ void nfs4_schedule_state_manager(struct nfs_client *clp) swapon = !test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state); if (!swapon) { + smp_mb__after_atomic(); wake_up_var(&clp->cl_state); return; }
--
2.47.0