On Fri, Mar 1, 2019 at 8:27 PM Steve Sistare <steven.sist...@oracle.com> wrote:
>
> megaraid_sas takes 1+ seconds to load while waiting for firmware:
>
> [2.822603] megaraid_sas 0000:03:00.0: Waiting for FW to come to ready state
> [3.871003] megaraid_sas 0000:03:00.0: FW now in Ready state
>
> This is due to the following loop in megasas_transition_to_ready(), which
> waits a minimum of 1 second, even though the FW becomes ready in tens of
> millisecs:
>
> /*
> * The cur_state should not last for more than max_wait secs
> */
> for (i = 0; i < max_wait; i++) {
> ...
> msleep(1000);
> ...
> dev_info(&instance->pdev->dev, "FW now in Ready state\n");
>
> This is a regression, caused by a change of the msleep granularity from 1 to
> 1000 due to concern about waiting too long on systems with coarse jiffies.
>
> To fix, increase iterations and use msleep(20), which results in:
>
> [2.670627] megaraid_sas 0000:03:00.0: Waiting for FW to come to ready state
> [2.739386] megaraid_sas 0000:03:00.0: FW now in Ready state
>
> Fixes: fb2f3e96d80f ("scsi: megaraid_sas: Fix msleep granularity")
> Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
Acked-by: Sumit Saxena <sumit.sax...@broadcom.com>
> ---
> drivers/scsi/megaraid/megaraid_sas_base.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c
> b/drivers/scsi/megaraid/megaraid_sas_base.c
> index a30c1b3..a707af5 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -3932,12 +3932,12 @@ static irqreturn_t megasas_isr(int irq, void *devp)
> /*
> * The cur_state should not last for more than max_wait secs
> */
> - for (i = 0; i < max_wait; i++) {
> + for (i = 0; i < max_wait * 50; i++) {
> curr_abs_state = instance->instancet->
> read_fw_status_reg(instance);
>
> if (abs_state == curr_abs_state) {
> - msleep(1000);
> + msleep(20);
> } else
> break;
> }
> --
> 1.8.3.1
>
