> On Mar 8, 2022, at 12:20 AM, Nilesh Javali <njavali@xxxxxxxxxxx> wrote:
>
> From: Quinn Tran <qutran@xxxxxxxxxxx>
>
> For session recovery, driver relies on the dpc thread to
> initiate certain operation. The dpc thread runs exclusively
> without the Mailbox interface being occupied. Recent code change
> for heartbeat check via mailbox cmd 0 is causing the dpc thread
> from carrying out its operation. This patch allows the higher
> priority error recovery to run first before running the lower priority
> heartbeat check.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: d94d8158e184 ("scsi: qla2xxx: Add heartbeat check")
> Signed-off-by: Quinn Tran <qutran@xxxxxxxxxxx>
> Signed-off-by: Nilesh Javali <njavali@xxxxxxxxxxx>
> ---
> drivers/scsi/qla2xxx/qla_def.h | 1 +
> drivers/scsi/qla2xxx/qla_os.c | 20 +++++++++++++++++---
> 2 files changed, 18 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
> index b0579bce5b88..80b02b077753 100644
> --- a/drivers/scsi/qla2xxx/qla_def.h
> +++ b/drivers/scsi/qla2xxx/qla_def.h
> @@ -4621,6 +4621,7 @@ struct qla_hw_data {
> struct workqueue_struct *wq;
> struct work_struct heartbeat_work;
> struct qlfc_fw fw_buf;
> + unsigned long last_heartbeat_run_jiffies;
>
> /* FCP_CMND priority support */
> struct qla_fcp_prio_cfg *fcp_prio_cfg;
> diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
> index d572a76d0fa0..89c7ac36a41a 100644
> --- a/drivers/scsi/qla2xxx/qla_os.c
> +++ b/drivers/scsi/qla2xxx/qla_os.c
> @@ -7218,7 +7218,7 @@ static bool qla_do_heartbeat(struct scsi_qla_host *vha)
> return do_heartbeat;
> }
>
> -static void qla_heart_beat(struct scsi_qla_host *vha)
> +static void qla_heart_beat(struct scsi_qla_host *vha, u16 dpc_started)
> {
> struct qla_hw_data *ha = vha->hw;
>
> @@ -7228,8 +7228,19 @@ static void qla_heart_beat(struct scsi_qla_host *vha)
> if (vha->hw->flags.eeh_busy || qla2x00_chip_is_down(vha))
> return;
>
> - if (qla_do_heartbeat(vha))
> + /*
> + * dpc thread cannot run if heartbeat is running at the same time.
> + * We also do not want to starve heartbeat task. Therefore, do
> + * heartbeat task at least once every 5 seconds.
> + */
> + if (dpc_started &&
> + time_before(jiffies, ha->last_heartbeat_run_jiffies + 5 * HZ))
> + return;
> +
> + if (qla_do_heartbeat(vha)) {
> + ha->last_heartbeat_run_jiffies = jiffies;
> queue_work(ha->wq, &ha->heartbeat_work);
> + }
> }
>
> /**************************************************************************
> @@ -7420,6 +7431,8 @@ qla2x00_timer(struct timer_list *t)
> start_dpc++;
> }
>
> + /* borrowing w to signify dpc will run */
> + w = 0;
> /* Schedule the DPC routine if needed */
> if ((test_bit(ISP_ABORT_NEEDED, &vha->dpc_flags) ||
> test_bit(LOOP_RESYNC_NEEDED, &vha->dpc_flags) ||
> @@ -7452,9 +7465,10 @@ qla2x00_timer(struct timer_list *t)
> test_bit(RELOGIN_NEEDED, &vha->dpc_flags),
> test_bit(PROCESS_PUREX_IOCB, &vha->dpc_flags));
> qla2xxx_wake_dpc(vha);
> + w = 1;
> }
>
> - qla_heart_beat(vha);
> + qla_heart_beat(vha, w);
>
> qla2x00_restart_timer(vha, WATCH_INTERVAL);
> }
> --
> 2.19.0.rc0
>
Looks Good.
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
--
Himanshu Madhani Oracle Linux Engineering
