libceph: prevent the race of incoming work during teardown
Add an atomic variable 'stopping' as flag in struct ceph_messenger,
set this flag to 1 in function ceph_destroy_client(), and add the condition code
in function ceph_data_ready() to test the flag value, if true(1), just return.
Signed-off-by: Guanjun He <gjhe@suse.com>
Reviewed-by: Sage Weil <sage@inktank.com>
diff --git a/include/linux/ceph/messenger.h b/include/linux/ceph/messenger.h
index cfb1bbd..a310d7f 100644
--- a/include/linux/ceph/messenger.h
+++ b/include/linux/ceph/messenger.h
@@ -50,6 +50,7 @@
struct ceph_entity_inst inst; /* my name+address */
struct ceph_entity_addr my_enc_addr;
+ atomic_t stopping;
bool nocrc;
/*
diff --git a/net/ceph/ceph_common.c b/net/ceph/ceph_common.c
index 58b09ef..3b45e01 100644
--- a/net/ceph/ceph_common.c
+++ b/net/ceph/ceph_common.c
@@ -495,6 +495,8 @@
{
dout("destroy_client %p\n", client);
+ atomic_set(&client->msgr.stopping, 1);
+
/* unmount */
ceph_osdc_stop(&client->osdc);
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 16814d1..63e1252 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -254,6 +254,9 @@
static void ceph_sock_data_ready(struct sock *sk, int count_unused)
{
struct ceph_connection *con = sk->sk_user_data;
+ if (atomic_read(&con->msgr->stopping)) {
+ return;
+ }
if (sk->sk_state != TCP_CLOSE_WAIT) {
dout("%s on %p state = %lu, queueing work\n", __func__,
@@ -2413,6 +2416,8 @@
encode_my_addr(msgr);
msgr->nocrc = nocrc;
+ atomic_set(&msgr->stopping, 0);
+
dout("%s %p\n", __func__, msgr);
}
EXPORT_SYMBOL(ceph_messenger_init);
