[Sheepdog] [PATCH v4 5/6] force some callbacks of cluster request running in worker thread

[levin li]

add a flag SD_FLAG_CMD_WORKER to vdi_req, when a node receives a
notified request with this flag, it will force process_main()
running in the __sd_notify() which is running in worker thread,
sometimes we need to notify a request to all the node, but we need
it to run in worker thread, in this case it's useful.

Signed-off-by: levin li <xingke.lwp at taobao.com>
---
 include/sheep.h |    1 +
 sheep/group.c   |   14 +++++++++++++-
 sheep/ops.c     |    3 ++-
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/include/sheep.h b/include/sheep.h
index 7e287c4..f72460d 100644
--- a/include/sheep.h
+++ b/include/sheep.h
@@ -60,6 +60,7 @@
 #define SD_FLAG_CMD_CREAT    0x0100
 #define SD_FLAG_CMD_EXCL     0x0200
 #define SD_FLAG_CMD_DEL      0x0400
+#define SD_FLAG_CMD_WORKER   0x0800
 
 #define SD_RES_OLD_NODE_VER  0x41 /* Remote node has an old epoch */
 #define SD_RES_NEW_NODE_VER  0x42 /* Remote node has a new epoch */
diff --git a/sheep/group.c b/sheep/group.c
index f2a62f9..93efb5f 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -613,6 +613,17 @@ static void update_cluster_info(struct join_message *msg,
 
 static void __sd_notify(struct event_struct *cevent)
 {
+	struct work_notify *w = container_of(cevent, struct work_notify, cev);
+	struct vdi_op_message *msg = w->msg;
+	const struct sd_req *req = (const struct sd_req *)&msg->req;
+	int ret = msg->rsp.result;
+	struct sd_op_template *op = get_sd_op(req->opcode);
+
+	if (ret == SD_RES_SUCCESS && has_process_bottom(op) &&
+			req->flags & SD_FLAG_CMD_WORKER) {
+		ret = do_process_bottom(op, req, (struct sd_rsp *)&msg->rsp, msg->data);
+		msg->rsp.result = ret;
+	}
 }
 
 static void __sd_notify_done(struct event_struct *cevent)
@@ -623,7 +634,8 @@ static void __sd_notify_done(struct event_struct *cevent)
 	int ret = msg->rsp.result;
 	struct sd_op_template *op = get_sd_op(msg->req.opcode);
 
-	if (ret == SD_RES_SUCCESS && has_process_bottom(op))
+	if (ret == SD_RES_SUCCESS && has_process_bottom(op) &&
+			!(msg->req.flags & SD_FLAG_CMD_WORKER))
 		ret = do_process_bottom(op, (const struct sd_req *)&msg->req,
 				      (struct sd_rsp *)&msg->rsp, msg->data);
 
diff --git a/sheep/ops.c b/sheep/ops.c
index ab5449e..439b714 100644
--- a/sheep/ops.c
+++ b/sheep/ops.c
@@ -40,7 +40,8 @@ struct sd_op_template {
 
 	/*
 	 * process_top() will be called in the worker thread, and
-	 * process_bottom() will be called in the main thread.
+	 * process_bottom() will be called in the main thread, except the
+	 * case that SD_FLAG_CMD_WORKER is set for the cluster request.
 	 *
 	 * If type is SD_OP_TYPE_CLUSTER, it is guaranteed that only
 	 * one node processes a cluster operation at the same time.
-- 
1.7.10