RE: [PATCH v6 3/8] scsi: ufs-qcom: Fix schedule while atomic error in ufs_qcom_dump_dbg_regs

From: Avri Altman
Date: Mon Jul 27 2020 - 09:05:52 EST


> Dumping testbus registers needs to sleep a bit intermittently as there are
> too many of them. Skip them for those contexts where sleep is not allowed.
>
> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> ---
> drivers/scsi/ufs/ufs-qcom.c | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
> index 7da27ee..7831b2b 100644
> --- a/drivers/scsi/ufs/ufs-qcom.c
> +++ b/drivers/scsi/ufs/ufs-qcom.c
> @@ -1651,13 +1651,16 @@ static void ufs_qcom_dump_dbg_regs(struct
> ufs_hba *hba)
> ufshcd_dump_regs(hba, REG_UFS_SYS1CLK_1US, 16 * 4,
> "HCI Vendor Specific Registers ");
>
> - /* sleep a bit intermittently as we are dumping too much data */
> ufs_qcom_print_hw_debug_reg_all(hba, NULL,
> ufs_qcom_dump_regs_wrapper);
> - udelay(1000);
> - ufs_qcom_testbus_read(hba);
> - udelay(1000);
> - ufs_qcom_print_unipro_testbus(hba);
> - udelay(1000);
> +
> + if (in_task()) {
> + /* sleep a bit intermittently as we are dumping too much data */
> + usleep_range(1000, 1100);
> + ufs_qcom_testbus_read(hba);
> + usleep_range(1000, 1100);
> + ufs_qcom_print_unipro_testbus(hba);
> + usleep_range(1000, 1100);
> + }
> }
How about moving the intermittent sleep out of the check if preemption is disabled?
And maybe then you need to switch back to uedlay?