Re: [RFC PATCH 1/5] hugetlb: add hugetlb helpers for soft dirty support
From: Peter Xu <peterx@redhat.com>
Date: 2021-02-17 16:25:53
Also in:
linux-s390, lkml
On Wed, Feb 10, 2021 at 04:03:18PM -0800, Mike Kravetz wrote:
quoted hunk ↗ jump to hunk
Add interfaces to set and clear soft dirty in hugetlb ptes. Make hugetlb interfaces needed for /proc clear_refs available outside hugetlb.c. arch/s390 has it's own version of most routines in asm-generic/hugetlb.h, so add new routines there as well. Signed-off-by: Mike Kravetz <redacted> --- arch/s390/include/asm/hugetlb.h | 30 ++++++++++++++++++++++++++++++ include/asm-generic/hugetlb.h | 30 ++++++++++++++++++++++++++++++ include/linux/hugetlb.h | 1 + mm/hugetlb.c | 10 +--------- 4 files changed, 62 insertions(+), 9 deletions(-)diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h index 60f9241e5e4a..b7d26248fb1c 100644 --- a/arch/s390/include/asm/hugetlb.h +++ b/arch/s390/include/asm/hugetlb.h@@ -105,6 +105,11 @@ static inline pte_t huge_pte_mkdirty(pte_t pte) return pte_mkdirty(pte); } +static inline pte_t huge_pte_mkyoung(pte_t pte) +{ + return pte_mkyoung(pte); +} + static inline pte_t huge_pte_wrprotect(pte_t pte) { return pte_wrprotect(pte);@@ -115,9 +120,34 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot) return pte_modify(pte, newprot); } +static inline bool huge_pte_soft_dirty(pte_t pte) +{ + return pte_soft_dirty(pte); +} + +static inline pte_t huge_pte_clear_soft_dirty(pte_t pte) +{ + return pte_clear_soft_dirty(pte); +} + +static inline pte_t huge_pte_swp_clear_soft_dirty(pte_t pte) +{ + return pte_swp_clear_soft_dirty(pte); +} +
Indeed asm/hugetlb.h of s390 didn't include asm-generic/hugetlb.h as what was normally done by asm/hugetlb.h of other archs. Do you know why it's special? E.g. huge_pte_wrprotect() of s390 version is actually the same of the default version. When I looked at the huge_pte_wrprotect() I also see that there seems to have no real user of __HAVE_ARCH_HUGE_PTE_WRPROTECT. Not sure whether it can be dropped. My gut feeling is that s390 should also include asm-generic/hugetlb.h but only redefine the helper only if necessary, since I see no point defining the same helper multiple times.
static inline bool gigantic_page_runtime_supported(void)
{
return true;
}
+#if !defined(__HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE) && !defined(MODULE)
+#include <asm/tlbflush.h>
+
+static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ flush_tlb_range(vma, start, end);
+}
+#endifSimilar question here, only ppc defined __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE, so IIUC it means s390 should simply use the default version, and it'll be great if we don't need to redefine it here. Thanks, -- Peter Xu