From ad3e6dabf6f7d9ffd68eb711191ef16cdbdd25f0 Mon Sep 17 00:00:00 2001 From: Stefan Roesch Date: Fri, 18 Nov 2022 16:52:14 -0800 Subject: [PATCH] mm: add /sys/class/bdi//min_ratio_fine knob This adds the min_ratio_fine knob. The knob specifies the values not based on 1 of 100, but instead 1 per million. Link: https://lkml.kernel.org/r/20221119005215.3052436-20-shr@devkernel.io Signed-off-by: Stefan Roesch Cc: Chris Mason Cc: Jens Axboe Signed-off-by: Andrew Morton --- mm/backing-dev.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 94c2382367cf..a53b9360b72e 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -180,6 +180,25 @@ static ssize_t min_ratio_store(struct device *dev, } BDI_SHOW(min_ratio, bdi->min_ratio / BDI_RATIO_SCALE) +static ssize_t min_ratio_fine_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + unsigned int ratio; + ssize_t ret; + + ret = kstrtouint(buf, 10, &ratio); + if (ret < 0) + return ret; + + ret = bdi_set_min_ratio_no_scale(bdi, ratio); + if (!ret) + ret = count; + + return ret; +} +BDI_SHOW(min_ratio_fine, bdi->min_ratio) + static ssize_t max_ratio_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -315,6 +334,7 @@ static DEVICE_ATTR_RW(strict_limit); static struct attribute *bdi_dev_attrs[] = { &dev_attr_read_ahead_kb.attr, &dev_attr_min_ratio.attr, + &dev_attr_min_ratio_fine.attr, &dev_attr_max_ratio.attr, &dev_attr_max_ratio_fine.attr, &dev_attr_min_bytes.attr,