librados: add rados_aio_create_completion2()

rados_aio_create_completion2() is almost identical to
rados_aio_create_completion(). the only difference is that the former
does not accept the `safe` callback. as it's an alias of `complete`
callback since af01db76f6

Signed-off-by: Kefu Chai <kchai@redhat.com>

src/include/rados/librados.h

@@ -1857,7 +1857,7 @@ typedef void (*rados_callback_t)(rados_completion_t cb, void *arg);
  *
  * @param cb_arg application-defined data passed to the callback functions
  * @param cb_complete the function to be called when the operation is
- * in memory on all relpicas
+ * in memory on all replicas
  * @param cb_safe the function to be called when the operation is on
  * stable storage on all replicas
  * @param pc where to store the completion
@@ -1868,6 +1868,23 @@ CEPH_RADOS_API int rados_aio_create_completion(void *cb_arg,
                                                rados_callback_t cb_safe,
 				               rados_completion_t *pc);
 
+/**
+ * Constructs a completion to use with asynchronous operations
+ *
+ * The complete callback corresponds to operation being acked.
+ *
+ * @note BUG: this should check for ENOMEM instead of throwing an exception
+ *
+ * @param cb_arg application-defined data passed to the callback functions
+ * @param cb_complete the function to be called when the operation is committed
+ * on all replicas
+ * @param pc where to store the completion
+ * @returns 0
+ */
+CEPH_RADOS_API int rados_aio_create_completion2(void *cb_arg,
+						rados_callback_t cb_complete,
+						rados_completion_t *pc);
+
 /**
  * Block until an operation completes
  *

src/librados/librados_c.cc

@@ -2240,6 +2240,20 @@ extern "C" int _rados_aio_create_completion(void *cb_arg,
 }
 LIBRADOS_C_API_BASE_DEFAULT(rados_aio_create_completion);
 
+extern "C" int _rados_aio_create_completion2(void *cb_arg,
+					     rados_callback_t cb_complete,
+					     rados_completion_t *pc)
+{
+  tracepoint(librados, rados_aio_create_completion2_enter, cb_arg, cb_complete);
+  librados::AioCompletionImpl *c = new librados::AioCompletionImpl;
+  if (cb_complete)
+    c->set_complete_callback(cb_arg, cb_complete);
+  *pc = c;
+  tracepoint(librados, rados_aio_create_completion2_exit, 0, *pc);
+  return 0;
+}
+LIBRADOS_C_API_BASE_DEFAULT(rados_aio_create_completion2);
+
 extern "C" int _rados_aio_wait_for_complete(rados_completion_t c)
 {
   tracepoint(librados, rados_aio_wait_for_complete_enter, c);

src/tracing/librados.tp

@@ -1991,6 +1991,26 @@ TRACEPOINT_EVENT(librados, rados_aio_create_completion_exit,
     )
 )
 
+TRACEPOINT_EVENT(librados, rados_aio_create_completion2_enter,
+    TP_ARGS(
+        void*, cb_arg,
+        rados_callback_t, cb_complete),
+    TP_FIELDS(
+        ctf_integer_hex(void*, cb_arg, cb_arg)
+        ctf_integer_hex(rados_callback_t, cb_complete, cb_complete)
+    )
+)
+
+TRACEPOINT_EVENT(librados, rados_aio_create_completion2_exit,
+    TP_ARGS(
+        int, retval,
+        rados_completion_t, completion),
+    TP_FIELDS(
+        ctf_integer(int, retval, retval)
+        ctf_integer_hex(rados_completion_t, completion, completion)
+    )
+)
+
 TRACEPOINT_EVENT(librados, rados_aio_wait_for_complete_enter,
     TP_ARGS(
         rados_completion_t, completion),