On 09/07/2020 06:35 PM, Huang Pei wrote: > On Mon, Sep 07, 2020 at 04:50:45PM +0800, maobibo wrote: >> Sorry for the late reply. >> >> Would you like to remove definition of macro pte_sw_mkyoung in header >> file include/linux/pgtable.h, since it is not used any more. >> >> The others look good to me. >> >> regards >> bibo,mao >> >> On 09/04/2020 04:49 PM, Huang Pei wrote: >>> This version removes pte_sw_mkyoung without polluting MM code and covers >>> both no-RIXI and RIXI MIPS CPUs and makes page fault delay of MIPS on par >>> with other architecture >>> >>> MIPS page fault path take 3 exceptions (1 TLB Miss + 2 TLB Invalid), but >>> the second TLB Invalid exception is just triggered by __update_tlb from >>> do_page_fault writing tlb without _PAGE_VALID set. By making userspace >>> mapping young by default, aka _PAGE_VALID and _PAGE_ACCESSED both set in >>> prot, it only take 1 TLB Miss + 1 TLB Invalid exceptions >>> >>> [1]: https://lkml.kernel.org/lkml/1591416169-26666-1-git-send-email >>> -maobibo@xxxxxxxxxxx/ >>> >>> Co-developed-by: Bibo Mao <maobibo@xxxxxxxxxx> >>> Co-developed-by: Huang Pei <huangpei@xxxxxxxxxxx> >>> Signed-off-by: Huang Pei <huangpei@xxxxxxxxxxx> >>> --- >>> arch/mips/include/asm/pgtable.h | 32 +++++++++++++++----------------- >>> arch/mips/mm/cache.c | 25 +++++++++++++------------ >>> mm/memory.c | 3 --- >>> 3 files changed, 28 insertions(+), 32 deletions(-) >>> >>> diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h >>> index dd7a0f552cac..aaafe3d6a0a1 100644 >>> --- a/arch/mips/include/asm/pgtable.h >>> +++ b/arch/mips/include/asm/pgtable.h >>> @@ -25,22 +25,22 @@ >>> struct mm_struct; >>> struct vm_area_struct; >>> >>> -#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \ >>> - _page_cachable_default) >>> -#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \ >>> - _page_cachable_default) >>> -#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \ >>> - _page_cachable_default) >>> -#define PAGE_READONLY __pgprot(_PAGE_PRESENT | \ >>> - _page_cachable_default) >>> -#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \ >>> - _PAGE_GLOBAL | _page_cachable_default) >>> -#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \ >>> - _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT) >>> -#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \ >>> - _page_cachable_default) >>> +#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \ >>> + _page_cachable_default) >>> +#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \ >>> + __READABLE | _page_cachable_default) >>> +#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \ >>> + __READABLE | _page_cachable_default) >>> +#define PAGE_READONLY __pgprot(_PAGE_PRESENT | __READABLE | \ >>> + _page_cachable_default) >>> +#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \ >>> + _PAGE_GLOBAL | _page_cachable_default) >>> +#define PAGE_KERNEL_NC __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \ >>> + _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT) >>> +#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \ >>> + _page_cachable_default) >>> #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \ >>> - __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED) >>> + __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED) >>> >>> /* >>> * If _PAGE_NO_EXEC is not defined, we can't do page protection for >>> @@ -414,8 +414,6 @@ static inline pte_t pte_mkyoung(pte_t pte) >>> return pte; >>> } >>> >>> -#define pte_sw_mkyoung pte_mkyoung >>> - >>> #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT >>> static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; } >>> >>> diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c >>> index 3e81ba000096..ed75f2871aad 100644 >>> --- a/arch/mips/mm/cache.c >>> +++ b/arch/mips/mm/cache.c >>> @@ -159,22 +159,23 @@ static inline void setup_protection_map(void) >>> { >>> if (cpu_has_rixi) { >>> protection_map[0] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ); >>> - protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC); >>> + protection_map[1] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE); >>> protection_map[2] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ); >>> - protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC); >>> - protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> - protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> - protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> - protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> + protection_map[3] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE); >>> + protection_map[4] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> + protection_map[5] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> + protection_map[6] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> + protection_map[7] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> >>> protection_map[8] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ); >>> - protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC); >>> + protection_map[9] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE); >>> protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ); >>> - protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE); >>> - protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> - protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT); >>> - protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE); >>> - protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE); >>> + protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | __READABLE); >>> + protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> + protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT | __READABLE); >>> + protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE); >>> + protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | __READABLE); >>> + >>> >>> } else { >>> protection_map[0] = PAGE_NONE; >>> diff --git a/mm/memory.c b/mm/memory.c >>> index 602f4283122f..5100ab5bcf77 100644 >>> --- a/mm/memory.c >>> +++ b/mm/memory.c >>> @@ -2705,7 +2705,6 @@ 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 >>> @@ -3386,7 +3385,6 @@ 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)); >>> >>> @@ -3661,7 +3659,6 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct page *page) >>> >>> 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 */ >>> > > I search for pte_sw_mkyoung/pte_{clear,mk,}_savewrite, none of which is > used, do I really need to remove pte_sw_mkyoung in this patch just for > *not used* ? > macro pte_sw_mkyoung is added by me previously, and it is defined as empty excepts mips system. If it is not used any more on mips sytem, I suggest that it should be removed here. regards bibo,mao
