arm64: tlb: Adjust stride and type of TLBI according to mmu_gather

Now that the core mmu_gather code keeps track of both the levels of page
table cleared and also whether or not these entries correspond to
intermediate entries, we can use this in our tlb_flush() callback to
reduce the number of invalidations we issue as well as their scope.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h
index bd00017..b078fde 100644 (file)
--- a/arch/arm64/include/asm/tlb.h
+++ b/arch/arm64/include/asm/tlb.h
@@ -34,20 +34,21 @@ static void tlb_flush(struct mmu_gather *tlb);
 static inline void tlb_flush(struct mmu_gather *tlb)
 {
        struct vm_area_struct vma = TLB_FLUSH_VMA(tlb->mm, 0);
+       bool last_level = !tlb->freed_tables;
+       unsigned long stride = tlb_get_unmap_size(tlb);
 
        /*
-        * The ASID allocator will either invalidate the ASID or mark
-        * it as used.
+        * If we're tearing down the address space then we only care about
+        * invalidating the walk-cache, since the ASID allocator won't
+        * reallocate our ASID without invalidating the entire TLB.
         */
-       if (tlb->fullmm)
+       if (tlb->fullmm) {
+               if (!last_level)
+                       flush_tlb_mm(tlb->mm);
                return;
+       }
 
-       /*
-        * The intermediate page table levels are already handled by
-        * the __(pte|pmd|pud)_free_tlb() functions, so last level
-        * TLBI is sufficient here.
-        */
-       __flush_tlb_range(&vma, tlb->start, tlb->end, PAGE_SIZE, true);
+       __flush_tlb_range(&vma, tlb->start, tlb->end, stride, last_level);
 }
 
 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,