On 9/24/21 12:08 AM, Aneesh Kumar K.V wrote: > Mike Kravetz <mike.kravetz@xxxxxxxxxx> writes: > >> Two new sysfs files are added to demote hugtlb pages. These files are >> both per-hugetlb page size and per node. Files are: >> demote_size - The size in Kb that pages are demoted to. (read-write) >> demote - The number of huge pages to demote. (write-only) >> >> By default, demote_size is the next smallest huge page size. Valid huge >> page sizes less than huge page size may be written to this file. When >> huge pages are demoted, they are demoted to this size. >> >> Writing a value to demote will result in an attempt to demote that >> number of hugetlb pages to an appropriate number of demote_size pages. >> >> NOTE: Demote interfaces are only provided for huge page sizes if there >> is a smaller target demote huge page size. For example, on x86 1GB huge >> pages will have demote interfaces. 2MB huge pages will not have demote >> interfaces. > > Should we also check if the platform allows for > gigantic_page_runtime_supported() ? > Yes, thanks! Looks like this may only be an issue for giganitc pages on power managed by firmware. Still, needs to be checked. Will update. Thanks, -- Mike Kravetz
