[Sheepdog] [PATCH 4/5] sheep: access local objects directly

[MORITA Kazutaka]

This patch fixes a dead lock which happens when sending vdi
creation/deletion requests continuously.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 sheep/sdnet.c      |   39 +++++++++++++++++++++++++++++++++++++++
 sheep/sheep_priv.h |    4 ++++
 sheep/store.c      |   48 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+), 0 deletions(-)

diff --git a/sheep/sdnet.c b/sheep/sdnet.c
index 4cfa6df..0040945 100644
--- a/sheep/sdnet.c
+++ b/sheep/sdnet.c
@@ -591,6 +591,19 @@ int write_object(struct sheepdog_node_list_entry *e,
 
 		n = obj_to_sheep(e, nodes, oid, i);
 
+		if (memcmp(e[n].addr, sys->this_node.addr, sizeof(e[n].addr)) == 0 &&
+		    e[n].port == sys->this_node.port) {
+			ret = write_object_local(oid, data, datalen, offset, nr,
+						 node_version, create);
+
+			if (ret != 0)
+				eprintf("fail %"PRIx64" %"PRIx32"\n", oid, ret);
+			else
+				success++;
+
+			continue;
+		}
+
 		addr_to_str(name, sizeof(name), e[n].addr, 0);
 
 		fd = connect_to(name, e[n].port);
@@ -637,6 +650,32 @@ int read_object(struct sheepdog_node_list_entry *e,
 	if (nr > nodes)
 		nr = nodes;
 
+	/* search a local object first */
+	for (i = 0; i < nr; i++) {
+		n = obj_to_sheep(e, nodes, oid, i);
+
+		if (memcmp(e[n].addr, sys->this_node.addr, sizeof(e[n].addr)) == 0 &&
+		    e[n].port == sys->this_node.port) {
+			ret = read_object_local(oid, data, datalen, offset, nr,
+						node_version);
+
+			if (ret < 0) {
+				eprintf("fail %"PRIx64" %"PRId32"\n", oid, ret);
+				return ret;
+			}
+
+			/* fix replication consistency */
+			if (nr > 1) {
+				if (write_object(e, nodes, node_version, oid,
+						 data, datalen, offset, nr, 0))
+					eprintf("failed to fix obj consistency\n");
+			}
+
+			return ret;
+		}
+
+	}
+
 	for (i = 0; i < nr; i++) {
 		unsigned wlen = 0, rlen = datalen;
 
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index d91e572..9b21e0f 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -162,6 +162,10 @@ int create_cluster(int port);
 
 void start_cpg_event_work(void);
 void store_queue_request(struct work *work, int idx);
+int write_object_local(uint64_t oid, char *data, unsigned int datalen,
+		       uint64_t offset, int copies, uint32_t epoch, int create);
+int read_object_local(uint64_t oid, char *data, unsigned int datalen,
+		      uint64_t offset, int copies, uint32_t epoch);
 
 int read_epoch(uint32_t *epoch, uint64_t *ctime,
 	       struct sheepdog_node_list_entry *entries, int *nr_entries);
diff --git a/sheep/store.c b/sheep/store.c
index 4b685f2..8fa4d9e 100644
--- a/sheep/store.c
+++ b/sheep/store.c
@@ -568,6 +568,54 @@ int update_epoch_store(uint32_t epoch)
 	return 0;
 }
 
+int write_object_local(uint64_t oid, char *data, unsigned int datalen,
+		       uint64_t offset, int copies, uint32_t epoch, int create)
+{
+	struct request req;
+	struct sd_obj_req *hdr = (struct sd_obj_req *)&req.rq;
+
+	memset(&req, 0, sizeof(req));
+
+	hdr->oid = oid;
+	if (create)
+		hdr->opcode = SD_OP_CREATE_AND_WRITE_OBJ;
+	else
+		hdr->opcode = SD_OP_WRITE_OBJ;
+	hdr->copies = copies;
+	hdr->flags = SD_FLAG_CMD_WRITE;
+	hdr->offset = offset;
+	hdr->data_length = datalen;
+	req.data = data;
+
+	return store_queue_request_local(&req, epoch);
+}
+
+int read_object_local(uint64_t oid, char *data, unsigned int datalen,
+		      uint64_t offset, int copies, uint32_t epoch)
+{
+	int ret;
+	struct request req;
+	struct sd_obj_req *hdr = (struct sd_obj_req *)&req.rq;
+	struct sd_obj_rsp *rsp = (struct sd_obj_rsp *)&req.rp;
+
+	memset(&req, 0, sizeof(req));
+
+	hdr->oid = oid;
+	hdr->opcode = SD_OP_READ_OBJ;
+	hdr->copies = copies;
+	hdr->flags = 0;
+	hdr->offset = offset;
+	hdr->data_length = datalen;
+	req.data = data;
+
+	ret = store_queue_request_local(&req, epoch);
+
+	if (ret != 0 || rsp->data_length != datalen)
+		return -rsp->result;
+
+	return rsp->data_length;
+}
+
 static int store_queue_request_local(struct request *req, uint32_t epoch)
 {
 	int fd = -1, copies;
-- 
1.5.6.5