mm: account the total_vm in the vm_stat_account()

vm_stat_account() accounts the shared_vm, stack_vm and reserved_vm now.
But we can also account for total_vm in the vm_stat_account() which makes
the code tidy.

Even for mprotect_fixup(), we can get the right result in the end.

Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: zyzii

arch/ia64/kernel/perfmon.c

@@ -2353,7 +2353,6 @@ pfm_smpl_buffer_alloc(struct task_struct *task, struct file *filp, pfm_context_t
 	 */
 	insert_vm_struct(mm, vma);
 
-	mm->total_vm  += size >> PAGE_SHIFT;
 	vm_stat_account(vma->vm_mm, vma->vm_flags, vma->vm_file,
 							vma_pages(vma));
 	up_write(&task->mm->mmap_sem);

include/linux/mm.h

@@ -1528,6 +1528,7 @@ void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long);
 static inline void vm_stat_account(struct mm_struct *mm,
 			unsigned long flags, struct file *file, long pages)
 {
+	mm->total_vm += pages;
 }
 #endif /* CONFIG_PROC_FS */
 

kernel/fork.c

@@ -381,10 +381,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 		struct file *file;
 
 		if (mpnt->vm_flags & VM_DONTCOPY) {
-			long pages = vma_pages(mpnt);
-			mm->total_vm -= pages;
 			vm_stat_account(mm, mpnt->vm_flags, mpnt->vm_file,
-								-pages);
+							-vma_pages(mpnt));
 			continue;
 		}
 		charge = 0;

mm/mmap.c

@@ -943,6 +943,8 @@ void vm_stat_account(struct mm_struct *mm, unsigned long flags,
 	const unsigned long stack_flags
 		= VM_STACK_FLAGS & (VM_GROWSUP|VM_GROWSDOWN);
 
+	mm->total_vm += pages;
+
 	if (file) {
 		mm->shared_vm += pages;
 		if ((flags & (VM_EXEC|VM_WRITE)) == VM_EXEC)
@@ -1347,7 +1349,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 out:
 	perf_event_mmap(vma);
 
-	mm->total_vm += len >> PAGE_SHIFT;
 	vm_stat_account(mm, vm_flags, file, len >> PAGE_SHIFT);
 	if (vm_flags & VM_LOCKED) {
 		if (!mlock_vma_pages_range(vma, addr, addr + len))
@@ -1707,7 +1708,6 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
 		return -ENOMEM;
 
 	/* Ok, everything looks good - let it rip */
-	mm->total_vm += grow;
 	if (vma->vm_flags & VM_LOCKED)
 		mm->locked_vm += grow;
 	vm_stat_account(mm, vma->vm_flags, vma->vm_file, grow);
@@ -1889,7 +1889,6 @@ static void remove_vma_list(struct mm_struct *mm, struct vm_area_struct *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);

mm/mremap.c

@@ -260,7 +260,6 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 	 * If this were a serious issue, we'd add a flag to do_munmap().
 	 */
 	hiwater_vm = mm->hiwater_vm;
-	mm->total_vm += new_len >> PAGE_SHIFT;
 	vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT);
 
 	if (do_munmap(mm, old_addr, old_len) < 0) {
@@ -497,7 +496,6 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
 				goto out;
 			}
 
-			mm->total_vm += pages;
 			vm_stat_account(mm, vma->vm_flags, vma->vm_file, pages);
 			if (vma->vm_flags & VM_LOCKED) {
 				mm->locked_vm += pages;