While implementing the AIO parts of the qemu-kvm driver I realized that
for every call to rados_aio_write the callback is called twice. The first
time, when the write is complete (committed to journal?) and the second
time, when the write is safe (committed to the object store?).
Usually I would think that a complete call is sufficient in most use
cases. However when I call rados_aio_release on the first callback, I get
an error message (on the second callback):
common/Mutex.h: In function 'void Mutex::Lock(bool)':
common/Mutex.h:97: FAILED assert(r == 0)
1: (RadosClient::C_aio_Safe::finish(int)+0x7f) [0x3ea0262e0f]
2: (Objecter::handle_osd_op_reply(MOSDOpReply*)+0x5cb) [0x3ea027fc2b]
3: (RadosClient::_dispatch(Message*)+0x7c) [0x3ea0250bac]
4: (RadosClient::ms_dispatch(Message*)+0x33) [0x3ea0250ee3]
5: (SimpleMessenger::dispatch_entry()+0x6a2) [0x3ea0268aa2]
6: (SimpleMessenger::DispatchThread::entry()+0x51) [0x3ea025db41]
7: (Thread::_entry_func(void*)+0xc) [0x3ea027645c]
8: /lib64/libpthread.so.0() [0x3293406a3a]
9: (clone()+0x6d) [0x3292cde67d]
NOTE: a copy of the executable, or `objdump -rdS <executable>` is needed to interpret this.
common/Mutex.h: In function 'void Mutex::Lock(bool)':
common/Mutex.h:97: FAILED assert(r == 0)
1: (RadosClient::C_aio_Safe::finish(int)+0x7f) [0x3ea0262e0f]
2: (Objecter::handle_osd_op_reply(MOSDOpReply*)+0x5cb) [0x3ea027fc2b]
3: (RadosClient::_dispatch(Message*)+0x7c) [0x3ea0250bac]
4: (RadosClient::ms_dispatch(Message*)+0x33) [0x3ea0250ee3]
5: (SimpleMessenger::dispatch_entry()+0x6a2) [0x3ea0268aa2]
6: (SimpleMessenger::DispatchThread::entry()+0x51) [0x3ea025db41]
7: (Thread::_entry_func(void*)+0xc) [0x3ea027645c]
8: /lib64/libpthread.so.0() [0x3293406a3a]
9: (clone()+0x6d) [0x3292cde67d]
NOTE: a copy of the executable, or `objdump -rdS <executable>` is needed to interpret this.
terminate called after throwing an instance of 'ceph::FailedAssertion*'
Aborted (core dumped)
To work around this, I’d suggest to re-enable rados_aio_set_callback.
This way it would possible to clear (cb=NULL) or change the callback
handler.
Regards,
Christian
---
src/librados.cc | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/src/librados.cc b/src/librados.cc
index 76d4a53..c3a34d7 100644
--- a/src/librados.cc
+++ b/src/librados.cc
@@ -1811,6 +1811,11 @@ extern "C" int rados_aio_create_completion(rados_callback_t cb, void *cba, rados
return 0;
}
+extern "C" int rados_aio_set_callback(rados_completion_t c, rados_callback_t cb, void *cba)
+{
+ return ((RadosClient::AioCompletion *)c)->set_callback(cb, cba);
+}
+
extern "C" int rados_aio_wait_for_complete(rados_completion_t c)
{
return ((RadosClient::AioCompletion *)c)->wait_for_complete();
--
1.6.6.1
--
Christian Brunner MUC.DE e.V.
Joseph-Dollinger-Bogen 14
D-80807 Muenchen
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
