NFS: remove l_pid field from nfs_lockowner

this field is not used in any important way and probably should
have been removed by

Commit: 8003d3c4aaa5 ("nfs4: treat lock owners as opaque values")

which removed the pid argument from nfs4_get_lock_state.

Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5321183..4d5897e 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1151,8 +1151,7 @@ int nfs_flush_incompatible(struct file *file, struct page *page)
 		if (l_ctx && flctx &&
 		    !(list_empty_careful(&flctx->flc_posix) &&
 		      list_empty_careful(&flctx->flc_flock))) {
-			do_flush |= l_ctx->lockowner.l_owner != current->files
-				|| l_ctx->lockowner.l_pid != current->tgid;
+			do_flush |= l_ctx->lockowner.l_owner != current->files;
 		}
 		nfs_release_request(req);
 		if (!do_flush)