Hi Jun,
It seems that you have ever posted this patch, If I remember correctly.
My concern is still if you disable dlm recovery via ::migrate_done. Then flag
DLM_LOCK_RES_RECOVERING can't be cleared.
So we can't purge the problematic lock resource since __dlm_lockres_unused()
needs to check that flag.
Finally, umount will run the while loop in dlm_migrate_all_locks() infinitely.
Or if I miss something?
Thanks,
Changwei
On 2018/3/15 21:00, piaojun wrote:
> Wait for dlm recovery done when migrating all lock resources in case that
> new lock resource left after leaving dlm domain. And the left lock
> resource will cause other nodes BUG.
>
> NodeA NodeB NodeC
>
> umount:
> dlm_unregister_domain()
> dlm_migrate_all_locks()
>
> NodeB down
>
> do recovery for NodeB
> and collect a new lockres
> form other live nodes:
>
> dlm_do_recovery
> dlm_remaster_locks
> dlm_request_all_locks:
>
> dlm_mig_lockres_handler
> dlm_new_lockres
> __dlm_insert_lockres
>
> at last NodeA become the
> master of the new lockres
> and leave domain:
> dlm_leave_domain()
>
> mount:
> dlm_join_domain()
>
> touch file and request
> for the owner of the new
> lockres, but all the
> other nodes said 'NO',
> so NodeC decide to be
> the owner, and send do
> assert msg to other
> nodes:
> dlmlock()
> dlm_get_lock_resource()
> dlm_do_assert_master()
>
> other nodes receive the msg
> and found two masters
> exist.
> at last cause BUG in
> dlm_assert_master_handler()
> -->BUG();
>
> Fixes: bc9838c4d44a ("dlm: allow dlm do recovery during shutdown")
>
> Signed-off-by: Jun Piao <piao...@huawei.com>
> Reviewed-by: Alex Chen <alex.c...@huawei.com>
> Reviewed-by: Yiwen Jiang <jiangyi...@huawei.com>
> ---
> fs/ocfs2/dlm/dlmcommon.h | 1 +
> fs/ocfs2/dlm/dlmdomain.c | 15 +++++++++++++++
> fs/ocfs2/dlm/dlmrecovery.c | 13 ++++++++++---
> 3 files changed, 26 insertions(+), 3 deletions(-)
>
> diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
> index 953c200..d06e27e 100644
> --- a/fs/ocfs2/dlm/dlmcommon.h
> +++ b/fs/ocfs2/dlm/dlmcommon.h
> @@ -140,6 +140,7 @@ struct dlm_ctxt
> u8 node_num;
> u32 key;
> u8 joining_node;
> + u8 migrate_done; /* set to 1 means node has migrated all lock resources
> */
> wait_queue_head_t dlm_join_events;
> unsigned long live_nodes_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
> unsigned long domain_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
> diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
> index 25b76f0..425081b 100644
> --- a/fs/ocfs2/dlm/dlmdomain.c
> +++ b/fs/ocfs2/dlm/dlmdomain.c
> @@ -461,6 +461,19 @@ static int dlm_migrate_all_locks(struct dlm_ctxt *dlm)
> cond_resched_lock(&dlm->spinlock);
> num += n;
> }
> +
> + if (!num) {
> + if (dlm->reco.state & DLM_RECO_STATE_ACTIVE) {
> + mlog(0, "%s: perhaps there are more lock resources "
> + "need to be migrated after dlm recovery\n",
> dlm->name);
> + ret = -EAGAIN;
> + } else {
> + mlog(0, "%s: we won't do dlm recovery after migrating "
> + "all lock resources\n", dlm->name);
> + dlm->migrate_done = 1;
> + }
> + }
> +
> spin_unlock(&dlm->spinlock);
> wake_up(&dlm->dlm_thread_wq);
>
> @@ -2038,6 +2051,8 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char
> *domain,
> dlm->joining_node = DLM_LOCK_RES_OWNER_UNKNOWN;
> init_waitqueue_head(&dlm->dlm_join_events);
>
> + dlm->migrate_done = 0;
> +
> dlm->reco.new_master = O2NM_INVALID_NODE_NUM;
> dlm->reco.dead_node = O2NM_INVALID_NODE_NUM;
>
> diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
> index 505ab42..d4336a5 100644
> --- a/fs/ocfs2/dlm/dlmrecovery.c
> +++ b/fs/ocfs2/dlm/dlmrecovery.c
> @@ -423,12 +423,11 @@ void dlm_wait_for_recovery(struct dlm_ctxt *dlm)
>
> static void dlm_begin_recovery(struct dlm_ctxt *dlm)
> {
> - spin_lock(&dlm->spinlock);
> + assert_spin_locked(&dlm->spinlock);
> BUG_ON(dlm->reco.state & DLM_RECO_STATE_ACTIVE);
> printk(KERN_NOTICE "o2dlm: Begin recovery on domain %s for node %u\n",
> dlm->name, dlm->reco.dead_node);
> dlm->reco.state |= DLM_RECO_STATE_ACTIVE;
> - spin_unlock(&dlm->spinlock);
> }
>
> static void dlm_end_recovery(struct dlm_ctxt *dlm)
> @@ -456,6 +455,13 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
>
> spin_lock(&dlm->spinlock);
>
> + if (dlm->migrate_done) {
> + mlog(0, "%s: no need do recovery after migrating all "
> + "lock resources\n", dlm->name);
> + spin_unlock(&dlm->spinlock);
> + return 0;
> + }
> +
> /* check to see if the new master has died */
> if (dlm->reco.new_master != O2NM_INVALID_NODE_NUM &&
> test_bit(dlm->reco.new_master, dlm->recovery_map)) {
> @@ -490,12 +496,13 @@ static int dlm_do_recovery(struct dlm_ctxt *dlm)
> mlog(0, "%s(%d):recovery thread found node %u in the recovery map!\n",
> dlm->name, task_pid_nr(dlm->dlm_reco_thread_task),
> dlm->reco.dead_node);
> - spin_unlock(&dlm->spinlock);
>
> /* take write barrier */
> /* (stops the list reshuffling thread, proxy ast handling) */
> dlm_begin_recovery(dlm);
>
> + spin_unlock(&dlm->spinlock);
> +
> if (dlm->reco.new_master == dlm->node_num)
> goto master_here;
>
_______________________________________________
Ocfs2-devel mailing list
Ocfs2-devel@oss.oracle.com
https://oss.oracle.com/mailman/listinfo/ocfs2-devel
