答复： [PATCH 3/3] Revert "MIPS: Flush wrong invalid FTLB entry for huge page"

[黄沛 <huangpei@loongson.cn>]

‎
  原始消息  
发件人： Huacai Chen
已发送： 2020年8月21日星期五 18:37
收件人： Huang Pei
抄送： Thomas Bogendoerfer; Paul Ambrose; Li Xuefeng; Yang Tiezhu; Gao Juxin; Fuxin Zhang; open list:MIPS
主题： Re: [PATCH 3/3] Revert "MIPS: Flush wrong invalid FTLB entry for huge page"

Got it, it is "too late", anything else?
 
I will re-send it next week


On Fri, Aug 21, 2020 at 3:24 PM Huang Pei <huangpei@loongson.cn> wrote:
>
> This reverts commit 0115f6cbf26663c86496bc56eeea293f85b77897.
>
> The fix in 0115f6cbf26663c86496bc56eeea293f85b77897 is two late, since
Do you means "too late"?

> __update_tlb hit the same problem first. So let __update_tlb fix it
>
> Signed-off-by: Huang Pei <huangpei@loongson.cn>
> ---
> arch/mips/mm/tlb-r4k.c | 15 ++++++++++++++-
> arch/mips/mm/tlbex.c | 25 ++++---------------------
> 2 files changed, 18 insertions(+), 22 deletions(-)
>
> diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
> index 38e2894d5fa3..cb8afa326b2c 100644
> --- a/arch/mips/mm/tlb-r4k.c
> +++ b/arch/mips/mm/tlb-r4k.c
> @@ -328,6 +328,7 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte)
> /* this could be a huge page */
> if (pmd_huge(*pmdp)) {
> unsigned long lo;
> + unsigned long entryhi;
> write_c0_pagemask(PM_HUGE_MASK);
> ptep = (pte_t *)pmdp;
> lo = pte_to_entrylo(pte_val(*ptep));
> @@ -335,7 +336,19 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte)
> write_c0_entrylo1(lo + (HPAGE_SIZE >> 7));
>
> mtc0_tlbw_hazard();
> - if (idx < 0)
> + if (idx >= current_cpu_data.tlbsizevtlb) {
> + /* hit in FTLB.
> + * Invalid it then tlbwr, since FTLB hold only base page*/
> + entryhi = read_c0_entryhi();
> + write_c0_entryhi(MIPS_ENTRYHI_EHINV);
> + tlb_write_indexed();
> + tlbw_use_hazard();
> + write_c0_entryhi(entryhi);
> +
> + }
> +
> +
> + if (idx < 0 || idx >= current_cpu_data.tlbsizevtlb)
> tlb_write_random();
> else
> tlb_write_indexed();
> diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
> index 14f8ba93367f..9c4cd08c00d3 100644
> --- a/arch/mips/mm/tlbex.c
> +++ b/arch/mips/mm/tlbex.c
> @@ -762,8 +762,7 @@ static void build_huge_update_entries(u32 **p, unsigned int pte,
> static void build_huge_handler_tail(u32 **p, struct uasm_reloc **r,
> struct uasm_label **l,
> unsigned int pte,
> - unsigned int ptr,
> - unsigned int flush)
> + unsigned int ptr)
> {
> #ifdef CONFIG_SMP
> UASM_i_SC(p, pte, 0, ptr);
> @@ -772,22 +771,6 @@ static void build_huge_handler_tail(u32 **p, struct uasm_reloc **r,
> #else
> UASM_i_SW(p, pte, 0, ptr);
> #endif
> - if (cpu_has_ftlb && flush) {
> - BUG_ON(!cpu_has_tlbinv);
> -
> - UASM_i_MFC0(p, ptr, C0_ENTRYHI);
> - uasm_i_ori(p, ptr, ptr, MIPS_ENTRYHI_EHINV);
> - UASM_i_MTC0(p, ptr, C0_ENTRYHI);
> - build_tlb_write_entry(p, l, r, tlb_indexed);
> -
> - uasm_i_xori(p, ptr, ptr, MIPS_ENTRYHI_EHINV);
> - UASM_i_MTC0(p, ptr, C0_ENTRYHI);
> - build_huge_update_entries(p, pte, ptr);
> - build_huge_tlb_write_entry(p, l, r, pte, tlb_random, 0);
> -
> - return;
> - }
> -
> build_huge_update_entries(p, pte, ptr);
> build_huge_tlb_write_entry(p, l, r, pte, tlb_indexed, 0);
> }
> @@ -2278,7 +2261,7 @@ static void build_r4000_tlb_load_handler(void)
> uasm_l_tlbl_goaround2(&l, p);
> }
> uasm_i_ori(&p, wr.r1, wr.r1, (_PAGE_ACCESSED | _PAGE_VALID));
> - build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 1);
> + build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
> #endif
>
> uasm_l_nopage_tlbl(&l, p);
> @@ -2334,7 +2317,7 @@ static void build_r4000_tlb_store_handler(void)
> build_tlb_probe_entry(&p);
> uasm_i_ori(&p, wr.r1, wr.r1,
> _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
> - build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 1);
> + build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
> #endif
>
> uasm_l_nopage_tlbs(&l, p);
> @@ -2391,7 +2374,7 @@ static void build_r4000_tlb_modify_handler(void)
> build_tlb_probe_entry(&p);
> uasm_i_ori(&p, wr.r1, wr.r1,
> _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
> - build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2, 0);
> + build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
> #endif
>
> uasm_l_nopage_tlbm(&l, p);
> --
> 2.17.1
>