Commit 516b7e52 authored by Sunil Mushran's avatar Sunil Mushran Committed by Mark Fasheh
Browse files

ocfs2/dlm: Do not purge lockres that is being migrated dlm_purge_lockres() 



This patch attempts to fix a fine race between purging and migration.

Signed-off-by: default avatarSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
parent 7141514b

fs/ocfs2/dlm/dlmthread.c

+18 −2
Original line number Diff line number Diff line
@@ -162,12 +162,28 @@ static int dlm_purge_lockres(struct dlm_ctxt *dlm, 


	spin_lock(&res->spinlock);

	if (!__dlm_lockres_unused(res)) {

		spin_unlock(&res->spinlock);

		mlog(0, "%s:%.*s: tried to purge but not unused\n",

		     dlm->name, res->lockname.len, res->lockname.name);

		return -ENOTEMPTY;

		__dlm_print_one_lock_resource(res);

		spin_unlock(&res->spinlock);

		BUG();

	}



	if (res->state & DLM_LOCK_RES_MIGRATING) {

		mlog(0, "%s:%.*s: Delay dropref as this lockres is "

		     "being remastered\n", dlm->name, res->lockname.len,

		     res->lockname.name);

		/* Re-add the lockres to the end of the purge list */

		if (!list_empty(&res->purge)) {

			list_del_init(&res->purge);

			list_add_tail(&res->purge, &dlm->purge_list);

		}

		spin_unlock(&res->spinlock);

		return 0;

	}



	master = (res->owner == dlm->node_num);



	if (!master)

		res->state |= DLM_LOCK_RES_DROPPING_REF;

	spin_unlock(&res->spinlock);