[Devel] [PATCH RHEL7 COMMIT] ms/proc: drop handling non-linear mappings

[Kirill Tkhai]

The commit is pushed to "branch-rh7-3.10.0-327.36.1.vz7.18.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-327.36.1.vz7.18.3
------>
commit ccb36d3460c10fbb868c65237d3bab4ba461f531
Author: Kirill A. Shutemov <kirill.shutemov at linux.intel.com>
Date:   Mon Oct 3 14:38:30 2016 +0000

    ms/proc: drop handling non-linear mappings
    
    We have to handle non-linear mappings for /proc/PID/{smaps,clear_refs}
    which is unused now.  Let's drop it.
    
    Signed-off-by: Kirill A. Shutemov <kirill.shutemov at linux.intel.com>
    Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
    
    https://jira.sw.ru/browse/PSBM-52992
    
    (cherry picked from commit 1da4b35b001481df99a6dcab12d5d39a876f7056)
    Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
    Reviewed-by: Cyrill Gorcunov <gorcunov at openvz.org>
---
 fs/proc/task_mmu.c | 15 ---------------
 1 file changed, 15 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index ca21827..48a7e53 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -442,7 +442,6 @@ struct mem_size_stats {
 	unsigned long anonymous;
 	unsigned long anonymous_thp;
 	unsigned long swap;
-	unsigned long nonlinear;
 	u64 pss;
 };
 
@@ -452,7 +451,6 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr,
 {
 	struct mem_size_stats *mss = walk->private;
 	struct vm_area_struct *vma = mss->vma;
-	pgoff_t pgoff = linear_page_index(vma, addr);
 	struct page *page = NULL;
 	int mapcount;
 
@@ -465,9 +463,6 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr,
 			mss->swap += ptent_size;
 		else if (is_migration_entry(swpent))
 			page = migration_entry_to_page(swpent);
-	} else if (pte_file(ptent)) {
-		if (pte_to_pgoff(ptent) != pgoff)
-			mss->nonlinear += ptent_size;
 	}
 
 	if (!page)
@@ -476,9 +471,6 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr,
 	if (PageAnon(page))
 		mss->anonymous += ptent_size;
 
-	if (page->index != pgoff)
-		mss->nonlinear += ptent_size;
-
 	mss->resident += ptent_size;
 	/* Accumulate the size in pages that have been accessed. */
 	if (pte_young(ptent) || page_is_young(page) || PageReferenced(page))
@@ -560,7 +552,6 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_ACCOUNT)]	= "ac",
 		[ilog2(VM_NORESERVE)]	= "nr",
 		[ilog2(VM_HUGETLB)]	= "ht",
-		[ilog2(VM_NONLINEAR)]	= "nl",
 		[ilog2(VM_ARCH_1)]	= "ar",
 		[ilog2(VM_DONTDUMP)]	= "dd",
 		[ilog2(VM_MIXEDMAP)]	= "mm",
@@ -633,10 +624,6 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		   (vma->vm_flags & VM_LOCKED) ?
 			(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
 
-	if (vma->vm_flags & VM_NONLINEAR)
-		seq_printf(m, "Nonlinear:      %8lu kB\n",
-				mss.nonlinear >> 10);
-
 	show_smap_vma_flags(m, vma);
 
 	if (m->count < m->size)  /* vma is copied successfully */
@@ -740,8 +727,6 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
 		ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
 	} else if (is_swap_pte(ptent)) {
 		ptent = pte_swp_clear_soft_dirty(ptent);
-	} else if (pte_file(ptent)) {
-		ptent = pte_file_clear_soft_dirty(ptent);
 	}
 
 	set_pte_at(vma->vm_mm, addr, pte, ptent);