[sheepdog] [PATCH 6/6] sheep: don't read epoch log from local in epoch_log_read_remote

[MORITA Kazutaka]

This patch uses get_vnode_info to get the current node membership in
epoch_log_read_remote.  It is because the delayed nodes don't have
epoch log in local store.  This also moves epoch_log_read_remote to
group.c since it is not a function to access local store.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 sheep/group.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 sheep/store.c | 39 ---------------------------------------
 2 files changed, 43 insertions(+), 39 deletions(-)

diff --git a/sheep/group.c b/sheep/group.c
index 49ba642..c2070b4 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -390,6 +390,11 @@ static bool add_delayed_node(uint32_t epoch, const struct sd_node *node)
 	return true;
 }
 
+static bool is_delayed_node(const struct sd_node *node)
+{
+	return !!find_entry_list(node, &sys->delayed_nodes);
+}
+
 /*
  * For a node that failed to join check if was part of the original
  * epoch, and if so add it to the list of node expected to be present
@@ -448,6 +453,44 @@ static void clear_exceptional_node_lists(void)
 		list_del(&n->list);
 }
 
+int epoch_log_read_remote(uint32_t epoch, struct sd_node *nodes, int len)
+{
+	int i, nr, ret;
+	struct vnode_info *vinfo = get_vnode_info();
+
+	nr = vinfo->nr_vnodes;
+	for (i = 0; i < nr; i++) {
+		struct sd_req hdr;
+		struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
+		const struct sd_node *node = vinfo->nodes + i;
+
+		if (node_is_local(node))
+			continue;
+
+		/* delayed nodes don't have epoch log */
+		if (is_delayed_node(node))
+			continue;
+
+		sd_init_req(&hdr, SD_OP_GET_EPOCH);
+		hdr.data_length = len;
+		hdr.obj.tgt_epoch = epoch;
+		hdr.epoch = sys_epoch();
+		ret = sheep_exec_req(&node->nid, &hdr, nodes);
+		if (ret != SD_RES_SUCCESS)
+			continue;
+
+		put_vnode_info(vinfo);
+		return rsp->data_length / sizeof(*nodes);
+	}
+
+	/*
+	 * If no node has targeted epoch log, return 0 here to at least
+	 * allow reading older epoch logs.
+	 */
+	put_vnode_info(vinfo);
+	return 0;
+}
+
 static int cluster_sanity_check(struct join_message *jm)
 {
 	uint64_t local_ctime = get_cluster_ctime();
diff --git a/sheep/store.c b/sheep/store.c
index 7f3b5cd..dbc687b 100644
--- a/sheep/store.c
+++ b/sheep/store.c
@@ -75,45 +75,6 @@ err_open:
 	return -1;
 }
 
-int epoch_log_read_remote(uint32_t epoch, struct sd_node *nodes, int len)
-{
-	int i, ret;
-	unsigned int nr, le;
-	struct sd_node local_nodes[SD_MAX_NODES];
-
-	le = get_latest_epoch();
-	if (!le)
-		return 0;
-
-	nr = epoch_log_read(le, local_nodes, sizeof(local_nodes));
-	if (nr < 0)
-		return -1;
-
-	for (i = 0; i < nr; i++) {
-		struct sd_req hdr;
-		struct sd_rsp *rsp = (struct sd_rsp *)&hdr;
-
-		if (node_is_local(&local_nodes[i]))
-			continue;
-
-		sd_init_req(&hdr, SD_OP_GET_EPOCH);
-		hdr.data_length = len;
-		hdr.obj.tgt_epoch = epoch;
-		hdr.epoch = sys_epoch();
-		ret = sheep_exec_req(&local_nodes[i].nid, &hdr, nodes);
-		if (ret != SD_RES_SUCCESS)
-			continue;
-
-		return rsp->data_length / sizeof(*nodes);
-	}
-
-	/*
-	 * If no node has targeted epoch log, return 0 here to at least
-	 * allow reading older epoch logs.
-	 */
-	return 0;
-}
-
 int epoch_log_read(uint32_t epoch, struct sd_node *nodes, int len)
 {
 	int fd;
-- 
1.8.1.3.566.gaa39828