diff mbox series

[v4] arm64: hugetlb: enable __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE

Message ID 20230802012731.62512-1-wangkefeng.wang@huawei.com (mailing list archive)
State New, archived
Headers show
Series [v4] arm64: hugetlb: enable __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE | expand

Commit Message

Kefeng Wang Aug. 2, 2023, 1:27 a.m. UTC
It is better to use huge page size instead of PAGE_SIZE
for stride when flush hugepage, which reduces the loop
in __flush_tlb_range().

Let's support arch's flush_hugetlb_tlb_range(), which is
used in hugetlb_unshare_all_pmds(), move_hugetlb_page_tables()
and hugetlb_change_protection() for now.

Note, for hugepages based on contiguous bit, it has to be
invalidated individually since the contiguous PTE bit is
just a hint, the hardware may or may not take it into account.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
v4: directly pass tlb_level to __flush_tlb_range() with PMD/PUD size,
    suggested by Catalin
v3: add tlb_level hint by using flush_pud/pmd_tlb_range, 
    suggested by Catalin

 arch/arm64/include/asm/hugetlb.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Comments

Muchun Song Aug. 2, 2023, 1:40 a.m. UTC | #1
> On Aug 2, 2023, at 09:27, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> 
> It is better to use huge page size instead of PAGE_SIZE
> for stride when flush hugepage, which reduces the loop
> in __flush_tlb_range().
> 
> Let's support arch's flush_hugetlb_tlb_range(), which is
> used in hugetlb_unshare_all_pmds(), move_hugetlb_page_tables()
> and hugetlb_change_protection() for now.
> 
> Note, for hugepages based on contiguous bit, it has to be
> invalidated individually since the contiguous PTE bit is
> just a hint, the hardware may or may not take it into account.
> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Catalin Marinas Aug. 2, 2023, 10:41 a.m. UTC | #2
On Wed, Aug 02, 2023 at 09:27:31AM +0800, Kefeng Wang wrote:
> It is better to use huge page size instead of PAGE_SIZE
> for stride when flush hugepage, which reduces the loop
> in __flush_tlb_range().
> 
> Let's support arch's flush_hugetlb_tlb_range(), which is
> used in hugetlb_unshare_all_pmds(), move_hugetlb_page_tables()
> and hugetlb_change_protection() for now.
> 
> Note, for hugepages based on contiguous bit, it has to be
> invalidated individually since the contiguous PTE bit is
> just a hint, the hardware may or may not take it into account.
> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index 6a4a1ab8eb23..a91d6219aa78 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -60,4 +60,19 @@  extern void huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
 
 #include <asm-generic/hugetlb.h>
 
+#define __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE
+static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
+					   unsigned long start,
+					   unsigned long end)
+{
+	unsigned long stride = huge_page_size(hstate_vma(vma));
+
+	if (stride == PMD_SIZE)
+		__flush_tlb_range(vma, start, end, stride, false, 2);
+	else if (stride == PUD_SIZE)
+		__flush_tlb_range(vma, start, end, stride, false, 1);
+	else
+		__flush_tlb_range(vma, start, end, PAGE_SIZE, false, 0);
+}
+
 #endif /* __ASM_HUGETLB_H */