If there is a lock resource conflict on multiple nodes, the lock on convert queue may not be granted forever.
EX.) grant queue: node0 grmode NL / rqmode IV node1 grmode NL / rqmode IV convert queue: node2 grmode NL / rqmode EX node3 grmode PR / rqmode EX wait queue: node4 grmode IV / rqmode PR node5 grmode IV / rqmode PR When the lock conversion (node PR -> NL) of node 0 is completed, the lock of node 2 should be grantable. However, __can_be_granted() returns 0 because the grmode of the lock on node 3 in convert queue is PR. When checking the lock at the head of convert queue, exclude queue_conflict() targeting convert queue. Signed-off-by: Tadashi Miyauchi <miyau...@toshiba-tops.co.jp> Signed-off-by: Tsutomu Owa <tsutomu....@toshiba.co.jp> --- fs/dlm/lock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c index 35502d4..dcdd26d 100644 --- a/fs/dlm/lock.c +++ b/fs/dlm/lock.c @@ -2336,7 +2336,8 @@ static int _can_be_granted(struct dlm_rsb *r, struct dlm_lkb *lkb, int now, * locks */ - if (queue_conflict(&r->res_convertqueue, lkb)) + if (!first_in_list(lkb, &r->res_convertqueue) && + queue_conflict(&r->res_convertqueue, lkb)) return 0; /* -- 2.7.4