libceph: preallocate message data items
Currently message data items are allocated with ceph_msg_data_create()
in setup_request_data() inside send_request(). send_request() has never
been allowed to fail, so each allocation is followed by a BUG_ON:
data = ceph_msg_data_create(...);
BUG_ON(!data);
It's been this way since support for multiple message data items was
added in commit 6644ed7b7e04 ("libceph: make message data be a pointer")
in 3.10.
There is no reason to delay the allocation of message data items until
the last possible moment and we certainly don't need a linked list of
them as they are only ever appended to the end and never erased. Make
ceph_msg_new2() take max_data_items and adapt the rest of the code.
Reported-by: Jerry Lee <leisurelysw24@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/include/linux/ceph/msgpool.h b/include/linux/ceph/msgpool.h
index 76c98a5..729cdf7 100644
--- a/include/linux/ceph/msgpool.h
+++ b/include/linux/ceph/msgpool.h
@@ -13,14 +13,15 @@ struct ceph_msgpool {
mempool_t *pool;
int type; /* preallocated message type */
int front_len; /* preallocated payload size */
+ int max_data_items;
};
-extern int ceph_msgpool_init(struct ceph_msgpool *pool, int type,
- int front_len, int size, bool blocking,
- const char *name);
+int ceph_msgpool_init(struct ceph_msgpool *pool, int type,
+ int front_len, int max_data_items, int size,
+ const char *name);
extern void ceph_msgpool_destroy(struct ceph_msgpool *pool);
-extern struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *,
- int front_len);
+struct ceph_msg *ceph_msgpool_get(struct ceph_msgpool *pool, int front_len,
+ int max_data_items);
extern void ceph_msgpool_put(struct ceph_msgpool *, struct ceph_msg *);
#endif
