On Fri, 5 Jun 2020 17:11:05 +0800 Bibo Mao <maobibo@xxxxxxxxxxx> wrote: > On MIPS system which has rixi hardware bit, page access bit is not > set in pgrot. For memory reading, there will be one page fault to > allocate physical page; however valid bit is not set, there will > be the second fast tlb-miss fault handling to set valid/access bit. > > This patch set page access/valid bit with pgrot if there is reading > access privilege. It will reduce one tlb-miss handling for memory > reading access. > > The valid/access bit will be cleared in order to track memory > accessing activity. If the page is accessed, tlb-miss fast handling > will set valid/access bit, pte_sw_mkyoung is not necessary in slow > page fault path. This patch removes pte_sw_mkyoung function which > is defined as empty function except MIPS system. > > ... > > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -2704,7 +2704,6 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) > } > flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte)); > entry = mk_pte(new_page, vma->vm_page_prot); > - entry = pte_sw_mkyoung(entry); > entry = maybe_mkwrite(pte_mkdirty(entry), vma); > /* > * Clear the pte entry and flush it first, before updating the > @@ -3379,7 +3378,6 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) > __SetPageUptodate(page); > > entry = mk_pte(page, vma->vm_page_prot); > - entry = pte_sw_mkyoung(entry); > if (vma->vm_flags & VM_WRITE) > entry = pte_mkwrite(pte_mkdirty(entry)); > > @@ -3662,7 +3660,6 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg, > > flush_icache_page(vma, page); > entry = mk_pte(page, vma->vm_page_prot); > - entry = pte_sw_mkyoung(entry); > if (write) > entry = maybe_mkwrite(pte_mkdirty(entry), vma); > /* copy-on-write page */ Only affects mips, so cheerily Acked-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>