NFS: Convert lookups of the open context to RCU
Reduce contention on the inode->i_lock by ensuring that we use RCU
when looking up the NFS open context.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 40a08cd4..be92ce4 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1437,8 +1437,8 @@ void nfs_inode_find_state_and_recover(struct inode *inode,
struct nfs4_state *state;
bool found = false;
- spin_lock(&inode->i_lock);
- list_for_each_entry(ctx, &nfsi->open_files, list) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
state = ctx->state;
if (state == NULL)
continue;
@@ -1456,7 +1456,7 @@ void nfs_inode_find_state_and_recover(struct inode *inode,
nfs4_state_mark_reclaim_nograce(clp, state))
found = true;
}
- spin_unlock(&inode->i_lock);
+ rcu_read_unlock();
nfs_inode_find_delegation_state_and_recover(inode, stateid);
if (found)
@@ -1469,13 +1469,13 @@ static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *ctx;
- spin_lock(&inode->i_lock);
- list_for_each_entry(ctx, &nfsi->open_files, list) {
+ rcu_read_lock();
+ list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
if (ctx->state != state)
continue;
set_bit(NFS_CONTEXT_BAD, &ctx->flags);
}
- spin_unlock(&inode->i_lock);
+ rcu_read_unlock();
}
static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)