> > > > 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 <luhongfei@xxxxxxxx> > > --- > > 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