There are three flags that control Write Booster Feature:
1. WB ON/OFF
2. WB Hibern Flush ON/OFF (implicitly)
3. WB Flush ON/OFF (explicit)
In the case of "Hibern Flush", one of the conditions for flush WB buffer is
that avail_wb_buff < wb_flush_threshold.
As we know, different users have different requirements for power
consumption and performance. Therefore, we need the ability to manually
set wb_flush_threshold, so that users can easily and flexibly adjust
the wb_flush_threshold value, thereby achieving a balance between power
consumption and performance.
So the sysfs attribute that controls this is necessary.
The meaning of wb_flush_threshold is the percentage of WB's total size,
such as 1 representing 10%, 2 representing 20%, and so on.
Signed-off-by: Lu Hongfei <[email protected]>
---
The modifications made compared to the previous version are as follows:
1. Using 'wb_flush_threshold == 0' insted of 'wb_flush_threshold <= 0'.
drivers/ufs/core/ufs-sysfs.c | 33 +++++++++++++++++++++++++++++++++
1 file changed, 33 insertions(+)
diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c
index cdf3d5f2b77b..347207f4e8ee
--- a/drivers/ufs/core/ufs-sysfs.c
+++ b/drivers/ufs/core/ufs-sysfs.c
@@ -298,6 +298,37 @@ static ssize_t enable_wb_buf_flush_store(struct device *dev,
return res < 0 ? res : count;
}
+static ssize_t wb_flush_threshold_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%u\n", hba->vps->wb_flush_threshold);
+}
+
+static ssize_t wb_flush_threshold_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ufs_hba *hba = dev_get_drvdata(dev);
+ unsigned int wb_flush_threshold;
+
+ if (kstrtouint(buf, 0, &wb_flush_threshold))
+ return -EINVAL;
+
+ /* The range of values for wb_flush_threshold is (0,10] */
+ if (wb_flush_threshold > UFS_WB_BUF_REMAIN_PERCENT(100) ||
+ wb_flush_threshold == 0) {
+ dev_err(dev, "The value of wb_flush_threshold is invalid!\n");
+ return -EINVAL;
+ }
+
+ hba->vps->wb_flush_threshold = wb_flush_threshold;
+
+ return count;
+}
+
static DEVICE_ATTR_RW(rpm_lvl);
static DEVICE_ATTR_RO(rpm_target_dev_state);
static DEVICE_ATTR_RO(rpm_target_link_state);
@@ -307,6 +338,7 @@ static DEVICE_ATTR_RO(spm_target_link_state);
static DEVICE_ATTR_RW(auto_hibern8);
static DEVICE_ATTR_RW(wb_on);
static DEVICE_ATTR_RW(enable_wb_buf_flush);
+static DEVICE_ATTR_RW(wb_flush_threshold);
static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
&dev_attr_rpm_lvl.attr,
@@ -318,6 +350,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
&dev_attr_auto_hibern8.attr,
&dev_attr_wb_on.attr,
&dev_attr_enable_wb_buf_flush.attr,
+ &dev_attr_wb_flush_threshold.attr,
NULL
};
--
2.39.0
>
> There are three flags that control Write Booster Feature:
>
> 1. WB ON/OFF
> 2. WB Hibern Flush ON/OFF (implicitly)
> 3. WB Flush ON/OFF (explicit)
>
> In the case of "Hibern Flush", one of the conditions for flush WB buffer is that
> avail_wb_buff < wb_flush_threshold.
>
> As we know, different users have different requirements for power
> consumption and performance. Therefore, we need the ability to manually
> set wb_flush_threshold, so that users can easily and flexibly adjust the
> wb_flush_threshold value, thereby achieving a balance between power
> consumption and performance.
>
> So the sysfs attribute that controls this is necessary.
>
> The meaning of wb_flush_threshold is the percentage of WB's total size, such
> as 1 representing 10%, 2 representing 20%, and so on.
>
> Signed-off-by: Lu Hongfei <[email protected]>
> ---
> The modifications made compared to the previous version are as follows:
> 1. Using 'wb_flush_threshold == 0' insted of 'wb_flush_threshold <= 0'.
>
> drivers/ufs/core/ufs-sysfs.c | 33 +++++++++++++++++++++++++++++++++
> 1 file changed, 33 insertions(+)
You are missing sysfs documentation.
>
> diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c index
> cdf3d5f2b77b..347207f4e8ee
> --- a/drivers/ufs/core/ufs-sysfs.c
> +++ b/drivers/ufs/core/ufs-sysfs.c
> @@ -298,6 +298,37 @@ static ssize_t enable_wb_buf_flush_store(struct
> device *dev,
> return res < 0 ? res : count;
> }
>
> +static ssize_t wb_flush_threshold_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf) {
> + struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> + return sysfs_emit(buf, "%u\n", hba->vps->wb_flush_threshold); }
> +
> +static ssize_t wb_flush_threshold_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct ufs_hba *hba = dev_get_drvdata(dev);
> + unsigned int wb_flush_threshold;
> +
> + if (kstrtouint(buf, 0, &wb_flush_threshold))
> + return -EINVAL;
Maybe also make note if wb not supported:
if (!ufshcd_is_wb_allowed(hba) {
dev_info(dev, "It is not allowed to configure WB buf flushing!\n");
return -EOPNOTSUPP;
}
Thanks,
Avri
> +
> + /* The range of values for wb_flush_threshold is (0,10] */
> + if (wb_flush_threshold > UFS_WB_BUF_REMAIN_PERCENT(100) ||
> + wb_flush_threshold == 0) {
> + dev_err(dev, "The value of wb_flush_threshold is invalid!\n");
> + return -EINVAL;
> + }
> +
> + hba->vps->wb_flush_threshold = wb_flush_threshold;
> +
> + return count;
> +}
> +
> static DEVICE_ATTR_RW(rpm_lvl);
> static DEVICE_ATTR_RO(rpm_target_dev_state);
> static DEVICE_ATTR_RO(rpm_target_link_state);
> @@ -307,6 +338,7 @@ static DEVICE_ATTR_RO(spm_target_link_state);
> static DEVICE_ATTR_RW(auto_hibern8);
> static DEVICE_ATTR_RW(wb_on);
> static DEVICE_ATTR_RW(enable_wb_buf_flush);
> +static DEVICE_ATTR_RW(wb_flush_threshold);
>
> static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
> &dev_attr_rpm_lvl.attr,
> @@ -318,6 +350,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
> &dev_attr_auto_hibern8.attr,
> &dev_attr_wb_on.attr,
> &dev_attr_enable_wb_buf_flush.attr,
> + &dev_attr_wb_flush_threshold.attr,
> NULL
> };
>
> --
> 2.39.0
> >
> > There are three flags that control Write Booster Feature:
> >
> > 1. WB ON/OFF
> > 2. WB Hibern Flush ON/OFF (implicitly)
> > 3. WB Flush ON/OFF (explicit)
> >
> > In the case of "Hibern Flush", one of the conditions for flush WB
> > buffer is that avail_wb_buff < wb_flush_threshold.
> >
> > As we know, different users have different requirements for power
> > consumption and performance. Therefore, we need the ability to
> > manually set wb_flush_threshold, so that users can easily and flexibly
> > adjust the wb_flush_threshold value, thereby achieving a balance
> > between power consumption and performance.
> >
> > So the sysfs attribute that controls this is necessary.
> >
> > The meaning of wb_flush_threshold is the percentage of WB's total
> > size, such as 1 representing 10%, 2 representing 20%, and so on.
> >
> > Signed-off-by: Lu Hongfei <[email protected]>
> > ---
> > The modifications made compared to the previous version are as follows:
> > 1. Using 'wb_flush_threshold == 0' insted of 'wb_flush_threshold <= 0'.
> >
> > drivers/ufs/core/ufs-sysfs.c | 33 +++++++++++++++++++++++++++++++++
> > 1 file changed, 33 insertions(+)
>
> You are missing sysfs documentation.
> >
> > diff --git a/drivers/ufs/core/ufs-sysfs.c
> > b/drivers/ufs/core/ufs-sysfs.c index cdf3d5f2b77b..347207f4e8ee
> > --- a/drivers/ufs/core/ufs-sysfs.c
> > +++ b/drivers/ufs/core/ufs-sysfs.c
> > @@ -298,6 +298,37 @@ static ssize_t enable_wb_buf_flush_store(struct
> > device *dev,
> > return res < 0 ? res : count;
> > }
> >
> > +static ssize_t wb_flush_threshold_show(struct device *dev,
> > + struct device_attribute *attr,
> > + char *buf) {
> > + struct ufs_hba *hba = dev_get_drvdata(dev);
> > +
> > + return sysfs_emit(buf, "%u\n", hba->vps->wb_flush_threshold);
> > + }
> > +
> > +static ssize_t wb_flush_threshold_store(struct device *dev,
> > + struct device_attribute *attr,
> > + const char *buf, size_t
> > +count) {
> > + struct ufs_hba *hba = dev_get_drvdata(dev);
> > + unsigned int wb_flush_threshold;
> > +
> > + if (kstrtouint(buf, 0, &wb_flush_threshold))
> > + return -EINVAL;
> Maybe also make note if wb not supported:
> if (!ufshcd_is_wb_allowed(hba) {
> dev_info(dev, "It is not allowed to configure WB buf flushing!\n");
> return -EOPNOTSUPP;
> }
I just noticed that Bart asked you to leave it out - sorry. Please ignore.
Thanks,
Avri