commit 3deb9fa1b539063c61d28c6939cfd000858f80ac
author Greg Reid <greid@codeaurora.org> Fri Oct 12 12:07:37 2012 -0400
committer Ethan Chen <intervigil@gmail.com> Mon Oct 28 15:12:31 2013 -0700
tree 973f05e01d35bd6a4c3af3fa14560833169a7989
parent 9584f632fb2dac1d1ef5bc5e7ebe904f7b9aab71

kernel: Add hooks for user-accessible timers in the kernel.

Hooks for user-accessible timers allow implementation of a
more efficient gettimeofday in user-space.

Change-Id: If2f63d010c1cf142eb84f3745617e756913e46f7
Signed-off-by: Brent DeGraaf <bdegraaf@codeaurora.org>

mm/mlock.c

diff --git a/mm/mlock.c b/mm/mlock.c
index ef726e8..38c77ab 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -229,7 +229,9 @@
 
 	if (!((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) ||
 			is_vm_hugetlb_page(vma) ||
-			vma == get_gate_vma(current->mm))) {
+			vma == get_gate_vma(current->mm) ||
+			((use_user_accessible_timers() &&
+				(vma == get_user_timers_vma(current->mm)))))) {
 
 		__mlock_vma_pages_range(vma, start, end, NULL);
 
@@ -324,7 +326,9 @@
 	int lock = !!(newflags & VM_LOCKED);
 
 	if (newflags == vma->vm_flags || (vma->vm_flags & VM_SPECIAL) ||
-	    is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm))
+	    is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm) ||
+	    ((use_user_accessible_timers()) &&
+		(vma == get_user_timers_vma(current->mm))))
 		goto out;	/* don't set VM_LOCKED,  don't count */
 
 	pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);