Re: [PATCH 3/7] pm80xx: Add sysfs attribute to track iop0 count

From: Jinpu Wang <jinpu.wang@cloud.ionos.com>
To: Viswas G <Viswas.G@microchip.com>
Cc: Linux SCSI Mailinglist <linux-scsi@vger.kernel.org>,
	Vasanthalakshmi.Tharmarajan@microchip.com,
	Ruksar.devadi@microchip.com,
	Vishakha Channapattan <vishakhavc@google.com>,
	Radha Ramachandran <radha@google.com>
Subject: Re: [PATCH 3/7] pm80xx: Add sysfs attribute to track iop0 count
Date: Thu, 4 Mar 2021 10:28:33 +0100	[thread overview]
Message-ID: <CAMGffEmfiAaXPi3B+8SrLHEhByCMrdO-EwUp=e87y==+rmL=Jw@mail.gmail.com> (raw)
In-Reply-To: <20210224155802.13292-4-Viswas.G@microchip.com>

On Wed, Feb 24, 2021 at 4:48 PM Viswas G <Viswas.G@microchip.com> wrote:
>
> From: Vishakha Channapattan <vishakhavc@google.com>
>
> A new sysfs variable 'ctl_iop0_count' is being introduced that tells if
> the controller is alive by indicating controller ticks. If on subsequent
> run we see the ticks changing that indicates that controller is not
> dead.
>
> Tested: Using 'ctl_iop0_count' sysfs variable we can see ticks
> incrementing
> mvae14:~# cat  /sys/class/scsi_host/host*/ctl_iop0_count
> IOP0TCNT=0x000000a3
> IOP0TCNT=0x000001db
> IOP0TCNT=0x000001e4
> IOP0TCNT=0x000001e7
>
> Signed-off-by: Vishakha Channapattan <vishakhavc@google.com>
> Signed-off-by: Viswas G <Viswas.G@microchip.com>
> Signed-off-by: Ruksar Devadi <Ruksar.devadi@microchip.com>
> Signed-off-by: Ashokkumar N <Ashokkumar.N@microchip.com>
> Signed-off-by: Radha Ramachandran <radha@google.com>
> ---
>  drivers/scsi/pm8001/pm8001_ctl.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>
> diff --git a/drivers/scsi/pm8001/pm8001_ctl.c b/drivers/scsi/pm8001/pm8001_ctl.c
> index d415bb12718c..8470bce2cee1 100644
> --- a/drivers/scsi/pm8001/pm8001_ctl.c
> +++ b/drivers/scsi/pm8001/pm8001_ctl.c
> @@ -943,6 +943,30 @@ static ssize_t ctl_raae_count_show(struct device *cdev,
>  }
>  static DEVICE_ATTR_RO(ctl_raae_count);
>
> +/**
> + * ctl_iop0_count_show - controller iop0 count check
> + * @cdev: pointer to embedded class device
> + * @buf: the buffer returned
> + *
> + * A sysfs 'read-only' shost attribute.
> + */
> +
> +static ssize_t ctl_iop0_count_show(struct device *cdev,
> +               struct device_attribute *attr, char *buf)
> +{
> +       struct Scsi_Host *shost = class_to_shost(cdev);
> +       struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
> +       struct pm8001_hba_info *pm8001_ha = sha->lldd_ha;
> +       unsigned int iop0cnt = 0;
> +       int c;
> +
> +       pm8001_dbg(pm8001_ha, IOCTL, "%s\n", __func__);
> +       iop0cnt = pm8001_mr32(pm8001_ha->general_stat_tbl_addr, 16);
> +       c = sprintf(buf, "IOP0TCNT=0x%08x\n", iop0cnt);
> +       return c;
> +}
New file should use  sysfs_emit instead of sprintf.
> +static DEVICE_ATTR_RO(ctl_iop0_count);
> +
>  struct device_attribute *pm8001_host_attrs[] = {
>         &dev_attr_interface_rev,
>         &dev_attr_controller_fatal_error,
> @@ -968,6 +992,7 @@ struct device_attribute *pm8001_host_attrs[] = {
>         &dev_attr_inc_fw_ver,
>         &dev_attr_ctl_mpi_state,
>         &dev_attr_ctl_raae_count,
> +       &dev_attr_ctl_iop0_count,
>         NULL,
>  };
>
> --
> 2.16.3
>