From mboxrd@z Thu Jan 1 00:00:00 1970 From: Selvin Xavier Subject: [PATCH for-rc 6/6] RDMA/bnxt_re: Avoid system hang during device un-reg Date: Thu, 15 Feb 2018 21:20:13 -0800 Message-ID: <1518758413-20850-7-git-send-email-selvin.xavier@broadcom.com> References: <1518758413-20850-1-git-send-email-selvin.xavier@broadcom.com> Return-path: In-Reply-To: <1518758413-20850-1-git-send-email-selvin.xavier-dY08KVG/lbpWk0Htik3J/w@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jgg-uk2M96/98Pc@public.gmane.org Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Selvin Xavier List-Id: linux-rdma@vger.kernel.org BNXT_RE_FLAG_TASK_IN_PROG doesn't handle multiple work requests posted together. Track schedule of multiple workqueue items by maintaining a per device counter and proceed with IB dereg only if this counter is zero. flush_workqueue is no longer required from NETDEV_UNREGISTER path. Signed-off-by: Selvin Xavier --- drivers/infiniband/hw/bnxt_re/bnxt_re.h | 2 +- drivers/infiniband/hw/bnxt_re/main.c | 7 +++---- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/hw/bnxt_re/bnxt_re.h b/drivers/infiniband/hw/bnxt_re/bnxt_re.h index 5692335..7463067 100644 --- a/drivers/infiniband/hw/bnxt_re/bnxt_re.h +++ b/drivers/infiniband/hw/bnxt_re/bnxt_re.h @@ -121,7 +121,6 @@ struct bnxt_re_dev { #define BNXT_RE_FLAG_HAVE_L2_REF 3 #define BNXT_RE_FLAG_RCFW_CHANNEL_EN 4 #define BNXT_RE_FLAG_QOS_WORK_REG 5 -#define BNXT_RE_FLAG_TASK_IN_PROG 6 #define BNXT_RE_FLAG_ISSUE_ROCE_STATS 29 struct net_device *netdev; unsigned int version, major, minor; @@ -159,6 +158,7 @@ struct bnxt_re_dev { atomic_t srq_count; atomic_t mr_count; atomic_t mw_count; + atomic_t sched_count; /* Max of 2 lossless traffic class supported per port */ u16 cosq[2]; diff --git a/drivers/infiniband/hw/bnxt_re/main.c b/drivers/infiniband/hw/bnxt_re/main.c index 560520c..b1aa5a7 100644 --- a/drivers/infiniband/hw/bnxt_re/main.c +++ b/drivers/infiniband/hw/bnxt_re/main.c @@ -656,7 +656,6 @@ static void bnxt_re_dev_remove(struct bnxt_re_dev *rdev) mutex_unlock(&bnxt_re_dev_lock); synchronize_rcu(); - flush_workqueue(bnxt_re_wq); kfree(rdev->gid_map); ib_dealloc_device(&rdev->ibdev); @@ -1454,7 +1453,7 @@ static void bnxt_re_task(struct work_struct *work) break; } smp_mb__before_atomic(); - clear_bit(BNXT_RE_FLAG_TASK_IN_PROG, &rdev->flags); + atomic_dec(&rdev->sched_count); kfree(re_work); } @@ -1516,7 +1515,7 @@ static int bnxt_re_netdev_event(struct notifier_block *notifier, /* netdev notifier will call NETDEV_UNREGISTER again later since * we are still holding the reference to the netdev */ - if (test_bit(BNXT_RE_FLAG_TASK_IN_PROG, &rdev->flags)) + if (atomic_read(&rdev->sched_count) > 0) goto exit; bnxt_re_ib_unreg(rdev, false); bnxt_re_remove_one(rdev); @@ -1536,7 +1535,7 @@ static int bnxt_re_netdev_event(struct notifier_block *notifier, re_work->vlan_dev = (real_dev == netdev ? NULL : netdev); INIT_WORK(&re_work->work, bnxt_re_task); - set_bit(BNXT_RE_FLAG_TASK_IN_PROG, &rdev->flags); + atomic_inc(&rdev->sched_count); queue_work(bnxt_re_wq, &re_work->work); } } -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html