Revert "MIPS: Remove race window in page fault handling"

Revert commit 2a4a8b1e5d9d ("MIPS: Remove race window in page fault
handling") because it increased the number of flushed dcache pages and
became a performance problem for some workloads.

Signed-off-by: Lars Persson <larper@axis.com>
Cc: linux-mips@linux-mips.org
Cc: paul.burton@imgtec.com
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9345/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h
index bffd46ca3694..819af9d057a8 100644
--- a/arch/mips/include/asm/pgtable.h
+++ b/arch/mips/include/asm/pgtable.h
@@ -127,10 +127,6 @@ do {									\
         }                                                               \
 } while(0)
 
-
-extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
-        pte_t pteval);
-
 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 
 #define pte_none(pte)           (!(((pte).pte_high) & ~_PAGE_GLOBAL))
@@ -152,6 +148,7 @@ static inline void set_pte(pte_t *ptep, pte_t pte)
                         buddy->pte_high |= _PAGE_GLOBAL;
         }
 }
+#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
 
 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
@@ -190,6 +187,7 @@ static inline void set_pte(pte_t *ptep, pte_t pteval)
         }
 #endif
 }
+#define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
 
 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 {
@@ -399,12 +397,15 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 
 extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
         pte_t pte);
+extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
+        pte_t pte);
 
 static inline void update_mmu_cache(struct vm_area_struct *vma,
         unsigned long address, pte_t *ptep)
 {
         pte_t pte = *ptep;
         __update_tlb(vma, address, pte);
+        __update_cache(vma, address, pte);
 }
 
 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,