From: Stefan Roesch shr@devkernel.io
mainline inclusion from mainline-v6.2-rc1 commit 4e230b406eda9bdf7f8a71e2cc3df18a824abcb0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAN96I
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
This introduces bdi_set_max_ratio_no_scale(). It uses the max granularity for the ratio. This function by the new sysfs knob max_ratio_fine.
Link: https://lkml.kernel.org/r/20221119005215.3052436-16-shr@devkernel.io Signed-off-by: Stefan Roesch shr@devkernel.io Cc: Chris Mason clm@meta.com Cc: Jens Axboe axboe@kernel.dk Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Yifan Qiao qiaoyifan4@huawei.com --- include/linux/backing-dev.h | 1 + mm/page-writeback.c | 11 ++++++++--- 2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index d8da5391f3d5..e2a09835d736 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -111,6 +111,7 @@ u64 bdi_get_min_bytes(struct backing_dev_info *bdi); u64 bdi_get_max_bytes(struct backing_dev_info *bdi); int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio); int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); +int bdi_set_max_ratio_no_scale(struct backing_dev_info *bdi, unsigned int max_ratio); int bdi_set_min_bytes(struct backing_dev_info *bdi, u64 min_bytes); int bdi_set_max_bytes(struct backing_dev_info *bdi, u64 max_bytes); int bdi_set_strict_limit(struct backing_dev_info *bdi, unsigned int strict_limit); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index e1cd2930853b..42a9b2664c10 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -752,6 +752,9 @@ static int __bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ra { int ret = 0;
+ if (max_ratio > 100 * BDI_RATIO_SCALE) + return -EINVAL; + spin_lock_bh(&bdi_lock); if (bdi->min_ratio > max_ratio) { ret = -EINVAL; @@ -764,6 +767,11 @@ static int __bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ra return ret; }
+int bdi_set_max_ratio_no_scale(struct backing_dev_info *bdi, unsigned int max_ratio) +{ + return __bdi_set_max_ratio(bdi, max_ratio); +} + int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio) { return __bdi_set_min_ratio(bdi, min_ratio * BDI_RATIO_SCALE); @@ -771,9 +779,6 @@ int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio)
int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio) { - if (max_ratio > 100) - return -EINVAL; - return __bdi_set_max_ratio(bdi, max_ratio * BDI_RATIO_SCALE); } EXPORT_SYMBOL(bdi_set_max_ratio);