Ceph » CephFS

#0  0x00007fecc1c5bfcb in raise () from /lib64/libpthread.so.0
#1  0x00007fecc316a1b5 in reraise_fatal (signum=6) at global/signal_handler.cc:71
#2  handle_fatal_signal (signum=6) at global/signal_handler.cc:133
#3  <signal handler called>
#4  0x00007fecc0a7b5f7 in raise () from /lib64/libc.so.6
#5  0x00007fecc0a7cce8 in abort () from /lib64/libc.so.6
#6  0x00007fecc3265957 in ceph::__ceph_assert_fail (assertion=assertion@entry=0x7fecc33f2daf "in->oset.objects.empty()",
    file=file@entry=0x7fecc33f1373 "client/Client.cc", line=line@entry=3136,
    func=func@entry=0x7fecc33f6a20 <Client::put_inode(Inode*, int)::__PRETTY_FUNCTION__> "void Client::put_inode(Inode*, int)") at common/assert.cc:78
#7  0x00007fecc30863a4 in Client::put_inode (this=this@entry=0x7fecce02c000, in=in@entry=0x7fecf5792d00, n=n@entry=1) at client/Client.cc:3136
#8  0x00007fecc30b9766 in Client::_ll_put (this=this@entry=0x7fecce02c000, in=in@entry=0x7fecf5792d00, num=num@entry=4) at client/Client.cc:9859
#9  0x00007fecc30ba106 in Client::ll_forget (this=0x7fecce02c000, in=0x7fecf5792d00, count=count@entry=4) at client/Client.cc:9900
#10 0x00007fecc30572d1 in fuse_ll_forget (req=0x7fed1a37bf00, ino=1099512610042, nlookup=3) at client/fuse_ll.cc:136
#11 0x00007fecc2a72054 in do_batch_forget () from /lib64/libfuse.so.2
#12 0x00007fecc2a71bdb in fuse_ll_process_buf () from /lib64/libfuse.so.2
#13 0x00007fecc2a6e471 in fuse_do_work () from /lib64/libfuse.so.2
#14 0x00007fecc1c54dc5 in start_thread () from /lib64/libpthread.so.0
#15 0x00007fecc0b3c28d in clone () from /lib64/libc.so.6

When we write a file, probably can be summarized as the following steps:

But sometimes the client will dropped inode's FILE_BUFFER | FILE_CACHE caps before the write of bh
callback, and then if the last one who have ref the anode start put_inode will found the set of the
inode can't be emptied. When client found one indoe's size smaller than mds have recorded, it will
do invalidate_inode_cache operation.

Code Path:

handle_client_replay -> insert_trace -> add_update_inode -> update_inode_file_bits -> _invalidate_inode_cache -> discard_set -> ObjectCacher::bh_remove

When we write a bh will increase its object's ref and decrease the ref in callback function.So if the writer hasn't callback and we delete the Tx bh may
lead the Object's data be empty but we can't do lru_unpin because the Object's ref is not equal to 1. When the inode's ref is decrease to zero by others
want empty the oset of the inode int put_inode. But due to have one object can't be closed, so will lead a assert fail.