Merge branch 'vm-cleanups' (unmap_vma() interface cleanup)

This series sanitizes the interface to unmap_vma().  The crazy interface
annoyed me no end when I was looking at unmap_single_vma(), which we can
spend quite a lot of time in (especially with loads that have a lot of
small fork/exec's: shell scripts etc).

Moving the nr_accounted calculations to where they belong at least
clarifies things a little.  I hope to come back to look at the
performance of this later, but if/when I get back to it I at least don't
have to see the crazy interfaces any more.

* vm-cleanups:
  vm: remove 'nr_accounted' calculations from the unmap_vmas() interfaces
  vm: simplify unmap_vmas() calling convention

2 files changed, 23 insertions, 23 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 6105f475fa86..1e77da6d82c1 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1295,7 +1295,7 @@ static void unmap_page_range(struct mmu_gather *tlb,
 
 static void unmap_single_vma(struct mmu_gather *tlb,
                 struct vm_area_struct *vma, unsigned long start_addr,
-                unsigned long end_addr, unsigned long *nr_accounted,
+                unsigned long end_addr,
                 struct zap_details *details)
 {
         unsigned long start = max(vma->vm_start, start_addr);
@@ -1307,9 +1307,6 @@ static void unmap_single_vma(struct mmu_gather *tlb,
         if (end <= vma->vm_start)
                 return;
 
-        if (vma->vm_flags & VM_ACCOUNT)
-                *nr_accounted += (end - start) >> PAGE_SHIFT;
-
         if (unlikely(is_pfn_mapping(vma)))
                 untrack_pfn_vma(vma, 0, 0);
 
@@ -1339,8 +1336,6 @@ static void unmap_single_vma(struct mmu_gather *tlb,
  * @vma: the starting vma
  * @start_addr: virtual address at which to start unmapping
  * @end_addr: virtual address at which to end unmapping
- * @nr_accounted: Place number of unmapped pages in vm-accountable vma's here
- * @details: details of nonlinear truncation or shared cache invalidation
  *
  * Unmap all pages in the vma list.
  *
@@ -1355,15 +1350,13 @@ static void unmap_single_vma(struct mmu_gather *tlb,
  */
 void unmap_vmas(struct mmu_gather *tlb,
                 struct vm_area_struct *vma, unsigned long start_addr,
-                unsigned long end_addr, unsigned long *nr_accounted,
-                struct zap_details *details)
+                unsigned long end_addr)
 {
         struct mm_struct *mm = vma->vm_mm;
 
         mmu_notifier_invalidate_range_start(mm, start_addr, end_addr);
         for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next)
-                unmap_single_vma(tlb, vma, start_addr, end_addr, nr_accounted,
-                                 details);
+                unmap_single_vma(tlb, vma, start_addr, end_addr, NULL);
         mmu_notifier_invalidate_range_end(mm, start_addr, end_addr);
 }
 
@@ -1376,19 +1369,21 @@ void unmap_vmas(struct mmu_gather *tlb,
  *
  * Caller must protect the VMA list
  */
-void zap_page_range(struct vm_area_struct *vma, unsigned long address,
+void zap_page_range(struct vm_area_struct *vma, unsigned long start,
                 unsigned long size, struct zap_details *details)
 {
         struct mm_struct *mm = vma->vm_mm;
         struct mmu_gather tlb;
-        unsigned long end = address + size;
-        unsigned long nr_accounted = 0;
+        unsigned long end = start + size;
 
         lru_add_drain();
         tlb_gather_mmu(&tlb, mm, 0);
         update_hiwater_rss(mm);
-        unmap_vmas(&tlb, vma, address, end, &nr_accounted, details);
-        tlb_finish_mmu(&tlb, address, end);
+        mmu_notifier_invalidate_range_start(mm, start, end);
+        for ( ; vma && vma->vm_start < end; vma = vma->vm_next)
+                unmap_single_vma(&tlb, vma, start, end, details);
+        mmu_notifier_invalidate_range_end(mm, start, end);
+        tlb_finish_mmu(&tlb, start, end);
 }
 
 /**
@@ -1406,13 +1401,12 @@ static void zap_page_range_single(struct vm_area_struct *vma, unsigned long addr
         struct mm_struct *mm = vma->vm_mm;
         struct mmu_gather tlb;
         unsigned long end = address + size;
-        unsigned long nr_accounted = 0;
 
         lru_add_drain();
         tlb_gather_mmu(&tlb, mm, 0);
         update_hiwater_rss(mm);
         mmu_notifier_invalidate_range_start(mm, address, end);
-        unmap_single_vma(&tlb, vma, address, end, &nr_accounted, details);
+        unmap_single_vma(&tlb, vma, address, end, details);
         mmu_notifier_invalidate_range_end(mm, address, end);
         tlb_finish_mmu(&tlb, address, end);
 }
diff --git a/mm/mmap.c b/mm/mmap.c
index 848ef52d9603..69a1889f3790 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1889,15 +1889,20 @@ find_extend_vma(struct mm_struct * mm, unsigned long addr)
  */
 static void remove_vma_list(struct mm_struct *mm, struct vm_area_struct *vma)
 {
+        unsigned long nr_accounted = 0;
+
         /* Update high watermark before we lower total_vm */
         update_hiwater_vm(mm);
         do {
                 long nrpages = vma_pages(vma);
 
+                if (vma->vm_flags & VM_ACCOUNT)
+                        nr_accounted += nrpages;
                 mm->total_vm -= nrpages;
                 vm_stat_account(mm, vma->vm_flags, vma->vm_file, -nrpages);
                 vma = remove_vma(vma);
         } while (vma);
+        vm_unacct_memory(nr_accounted);
         validate_mm(mm);
 }
 
@@ -1912,13 +1917,11 @@ static void unmap_region(struct mm_struct *mm,
 {
         struct vm_area_struct *next = prev? prev->vm_next: mm->mmap;
         struct mmu_gather tlb;
-        unsigned long nr_accounted = 0;
 
         lru_add_drain();
         tlb_gather_mmu(&tlb, mm, 0);
         update_hiwater_rss(mm);
-        unmap_vmas(&tlb, vma, start, end, &nr_accounted, NULL);
-        vm_unacct_memory(nr_accounted);
+        unmap_vmas(&tlb, vma, start, end);
         free_pgtables(&tlb, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS,
                                  next ? next->vm_start : 0);
         tlb_finish_mmu(&tlb, start, end);
@@ -2305,8 +2308,7 @@ void exit_mmap(struct mm_struct *mm)
         tlb_gather_mmu(&tlb, mm, 1);
         /* update_hiwater_rss(mm) here? but nobody should be looking */
         /* Use -1 here to ensure all VMAs in the mm are unmapped */
-        unmap_vmas(&tlb, vma, 0, -1, &nr_accounted, NULL);
-        vm_unacct_memory(nr_accounted);
+        unmap_vmas(&tlb, vma, 0, -1);
 
         free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, 0);
         tlb_finish_mmu(&tlb, 0, -1);
@@ -2315,8 +2317,12 @@ void exit_mmap(struct mm_struct *mm)
          * Walk the list again, actually closing and freeing it,
          * with preemption enabled, without holding any MM locks.
          */
-        while (vma)
+        while (vma) {
+                if (vma->vm_flags & VM_ACCOUNT)
+                        nr_accounted += vma_pages(vma);
                 vma = remove_vma(vma);
+        }
+        vm_unacct_memory(nr_accounted);
 
         BUG_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT);
 }