Suspicious warnings during shutdown

[BusyJay]

Bug Report

What version of TiKV are you using?

v4.0.11

What operating system and CPU are you using?

Doesn't matter.

Steps to reproduce

Shutdown the TiKV

What did you expect?

Everything work fine

What did happened?

[2021/05/26 22:55:43.967 +08:00] [WARN] [mod.rs:396] ["async snapshot callback is dropped"] [backtrace="stack backtrace:\n   0: tikv::storage::kv::drop_snapsh
ot_callback\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/tikv/src/storage/kv/mod.rs:395\n      core::ops::function::FnOnce::
call_once\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ops/function.rs:232\n   1: <tikv_util::callback::MustCall<T,C,A> as cor
e::ops::drop::Drop>::drop\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/tikv/components/tikv_util/src/callback.rs:48\n      c
ore::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n      core::ptr::real_drop_in_place\
n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n   2: core::ptr::real_drop_in_place\n             at /rustc/0de96
d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n      core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817
669bc8/src/libcore/ptr/mod.rs:182\n   3: core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs
:182\n      core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n   4: core::ptr::real_d
rop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n      core::ptr::real_drop_in_place\n             at
 /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n   5: core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c
18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n      core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libco
re/ptr/mod.rs:182\n      core::ptr::drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:172\n      alloc::ve
c::Vec<T>::truncate\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/liballoc/vec.rs:746\n      alloc::vec::Vec<T>::clear\n             at
 /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/liballoc/vec.rs:1318\n      raftstore::store::read_queue::ReadIndexQueue::clear_all\n             at comp
onents/raftstore/src/store/read_queue.rs:120\n   6: <raftstore::store::fsm::peer::PeerFsm<E> as core::ops::drop::Drop>::drop\n             at components/rafts
tore/src/store/peer.rs:2779\n      core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n
   7: core::ptr::real_drop_in_place\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ptr/mod.rs:182\n      batch_system::fsm::FsmS
tate<N>::release\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/tikv/components/batch-system/src/fsm.rs:114\n      batch_syste
m::mailbox::BasicMailbox<Owner>::release\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/tikv/components/batch-system/src/mailb
ox.rs:39\n      batch_system::batch::Batch<N,C>::release\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/tikv/components/batch-
system/src/batch.rs:124\n      batch_system::batch::Poller<N,C,Handler>::poll\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v4.0.11/t
ikv/components/batch-system/src/batch.rs:340\n   8: batch_system::batch::BatchSystem<N,C>::spawn::{{closure}}\n             at /home/jenkins/agent/workspace/b
uild_tikv_multi_branch_v4.0.11/tikv/components/batch-system/src/batch.rs:398\n      std::sys_common::backtrace::__rust_begin_short_backtrace\n             at 
/rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/sys_common/backtrace.rs:136\n   9: std::thread::Builder::spawn_unchecked::{{closure}}::{{closure}}\
n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/thread/mod.rs:469\n      <std::panic::AssertUnwindSafe<F> as core::ops::function::
FnOnce<()>>::call_once\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/panic.rs:318\n      std::panicking::try::do_call\n         
    at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/panicking.rs:292\n      std::panicking::try\n             at /rustc/0de96d37fbcc54978458c18f
5067cd9817669bc8//src/libpanic_unwind/lib.rs:78\n      std::panic::catch_unwind\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/pa
nic.rs:394\n      std::thread::Builder::spawn_unchecked::{{closure}}\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libstd/thread/mod.rs
:468\n      core::ops::function::FnOnce::call_once{{vtable.shim}}\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/libcore/ops/function.rs
:232\n  10: <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/liballoc/
boxed.rs:1022\n  11: <alloc::boxed::Box<F> as core::ops::function::FnOnce<A>>::call_once\n             at /rustc/0de96d37fbcc54978458c18f5067cd9817669bc8/src/
liballoc/boxed.rs:1022\n      std::sys_common::thread::start_thread\n             at src/libstd/sys_common/thread.rs:13\n      std::sys::unix::thread::Thread:
:new::thread_start\n             at src/libstd/sys/unix/thread.rs:80\n  12: start_thread\n  13: clone\n"]