diff options
| author | Trond Myklebust <trond.myklebust@hammerspace.com> | 2018-09-02 15:57:01 -0400 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2018-09-30 15:35:17 -0400 |
| commit | 0de43976fbe716379084f954b1e370c35aa87bf0 (patch) | |
| tree | 64a6ea935fc8015c7369b9ece308771585cd3053 /fs/nfs/delegation.c | |
| parent | 6ba0c4e5bb08cc929662588aa2015e0ee7ee9376 (diff) | |
| download | lwn-0de43976fbe716379084f954b1e370c35aa87bf0.tar.gz lwn-0de43976fbe716379084f954b1e370c35aa87bf0.zip | |
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>
Diffstat (limited to 'fs/nfs/delegation.c')
| -rw-r--r-- | fs/nfs/delegation.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index f033f3a69a3b..76d205d1c7bc 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -136,8 +136,8 @@ static int nfs_delegation_claim_opens(struct inode *inode, int err; again: - 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; @@ -147,8 +147,9 @@ again: continue; if (!nfs4_stateid_match(&state->stateid, stateid)) continue; - get_nfs_open_context(ctx); - spin_unlock(&inode->i_lock); + if (!get_nfs_open_context(ctx)) + continue; + rcu_read_unlock(); sp = state->owner; /* Block nfs4_proc_unlck */ mutex_lock(&sp->so_delegreturn_mutex); @@ -164,7 +165,7 @@ again: return err; goto again; } - spin_unlock(&inode->i_lock); + rcu_read_unlock(); return 0; } |