diff options
| author | Ingo Molnar <mingo@kernel.org> | 2015-04-08 09:01:54 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-04-08 09:01:54 +0200 |
| commit | 4bcc7827b02feea2c762fa6d46a1bffb300d7403 (patch) | |
| tree | 45fd2b64247cd44201fe519720494d4bf01b7014 /mm/memory.c | |
| parent | 3f705dfdf85a6416f5f12e52b7610144a99cbedc (diff) | |
| parent | f22e6e847115abc3a0e2ad7bb18d243d42275af1 (diff) | |
Merge tag 'v4.0-rc7' into x86/asm, to resolve conflicts
Conflicts:
arch/x86/kernel/entry_64.S
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/mm/memory.c b/mm/memory.c index 411144f977b1..97839f5c8c30 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3035,6 +3035,7 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma, int last_cpupid; int target_nid; bool migrated = false; + bool was_writable = pte_write(pte); int flags = 0; /* A PROT_NONE fault should not end up here */ @@ -3059,6 +3060,8 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma, /* Make it present again */ pte = pte_modify(pte, vma->vm_page_prot); pte = pte_mkyoung(pte); + if (was_writable) + pte = pte_mkwrite(pte); set_pte_at(mm, addr, ptep, pte); update_mmu_cache(vma, addr, ptep); @@ -3069,16 +3072,14 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma, } /* - * Avoid grouping on DSO/COW pages in specific and RO pages - * in general, RO pages shouldn't hurt as much anyway since - * they can be in shared cache state. - * - * FIXME! This checks "pmd_dirty()" as an approximation of - * "is this a read-only page", since checking "pmd_write()" - * is even more broken. We haven't actually turned this into - * a writable page, so pmd_write() will always be false. + * Avoid grouping on RO pages in general. RO pages shouldn't hurt as + * much anyway since they can be in shared cache state. This misses + * the case where a mapping is writable but the process never writes + * to it but pte_write gets cleared during protection updates and + * pte_dirty has unpredictable behaviour between PTE scan updates, + * background writeback, dirty balancing and application behaviour. */ - if (!pte_dirty(pte)) + if (!(vma->vm_flags & VM_WRITE)) flags |= TNF_NO_GROUP; /* @@ -3102,7 +3103,8 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma, if (migrated) { page_nid = target_nid; flags |= TNF_MIGRATED; - } + } else + flags |= TNF_MIGRATE_FAIL; out: if (page_nid != -1) |