On 17 Dec 2024, at 1:43, Ryan Roberts wrote: > On 17/12/2024 04:18, Matthew Wilcox wrote: >> On Mon, Dec 16, 2024 at 10:20:54PM +0530, Dev Jain wrote: >>> -static int hpage_collapse_scan_pmd(struct mm_struct *mm, >>> +static int hpage_collapse_scan_ptes(struct mm_struct *mm, >> >> i don't think this is necessary at all. you're scanning a pmd. >> you might not be scanning in order to collapse to a pmd, but pmd >> is the level you're scanning at. >> > > Sorry Matthew, I don't really understand this statement. Prior to the change we > were scanning all PTE entries in a PTE table with the aim of collapsing to a PMD > entry. After the change we are scanning some PTE entries in a PTE table with the > aim of collapsing to either to a multi-PTE-mapped folio or a single-PMD-mapped > folio. > > So personally I think "scan_pmd" was a misnomer even before the change - we are > scanning the ptes. But there are still a lot of scan_pmd code in the function, for example, VM_BUG_ON(address & ~HPAGE_PMD_MASK), _pte < pte + HPAGE_PMD_NR in the function. These need to be changed along with function renaming. If after the change only a subset of PTEs are scanned within a PMD, maybe a scan_range parameter can be added. Best Regards, Yan, Zi
