linux-kernel - [patch 2/3 take2] smaps: add pages referenced count to smaps

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 6 Feb 2007 22:15:52 -0800 (PST)
From:	David Rientjes <rientjes@...gle.com>
To:	Andrew Morton <akpm@...l.org>
cc:	Hugh Dickins <hugh@...itas.com>, Paul Mundt <lethal@...ux-sh.org>,
	Christoph Lameter <clameter@....com>,
	linux-kernel@...r.kernel.org
Subject: [patch 2/3 take2] smaps: add pages referenced count to smaps

Adds an additional unsigned long field to struct mem_size_stats:
referenced.  For each page table entry that is walked for the VMA in the
smaps code, this field is incremented by PAGE_SIZE if it has pte-reference
bits.

An additional line was added to the /proc/pid/smaps output for each VMA
to indicate how many pages within it are currently marked as accessed
(referenced).

Cc: Hugh Dickins <hugh@...itas.com>
Cc: Paul Mundt <lethal@...ux-sh.org>
Cc: Christoph Lameter <clameter@....com>
Signed-off-by: David Rientjes <rientjes@...gle.com>
---
 fs/proc/task_mmu.c |   20 +++++++++++++-------
 1 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e87824b..50bd004 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -120,6 +120,7 @@ struct mem_size_stats
 	unsigned long shared_dirty;
 	unsigned long private_clean;
 	unsigned long private_dirty;
+	unsigned long referenced;
 };
 
 struct pte_walker {
@@ -190,18 +191,20 @@ static int show_map_internal(struct seq_file *m, void *v, struct mem_size_stats
 
 	if (mss)
 		seq_printf(m,
-			   "Size:          %8lu kB\n"
-			   "Rss:           %8lu kB\n"
-			   "Shared_Clean:  %8lu kB\n"
-			   "Shared_Dirty:  %8lu kB\n"
-			   "Private_Clean: %8lu kB\n"
-			   "Private_Dirty: %8lu kB\n",
+			   "Size:           %8lu kB\n"
+			   "Rss:            %8lu kB\n"
+			   "Shared_Clean:   %8lu kB\n"
+			   "Shared_Dirty:   %8lu kB\n"
+			   "Private_Clean:  %8lu kB\n"
+			   "Private_Dirty:  %8lu kB\n"
+			   "Pgs_Referenced: %8lu kB\n",
 			   (vma->vm_end - vma->vm_start) >> 10,
 			   mss->resident >> 10,
 			   mss->shared_clean  >> 10,
 			   mss->shared_dirty  >> 10,
 			   mss->private_clean >> 10,
-			   mss->private_dirty >> 10);
+			   mss->private_dirty >> 10,
+			   mss->referenced >> 10);
 
 	if (m->count < m->size)  /* vma is copied successfully */
 		m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
@@ -302,6 +305,9 @@ static void smaps_pte_func(struct pte_walker *walker, pte_t *pte,
 	if (!page)
 		return;
 
+	/* Accumulate the number of pages that have been accessed. */
+	if (pte_young(ptent) || PageReferenced(page))
+		mss->referenced += PAGE_SIZE;
 	if (page_mapcount(page) >= 2) {
 		if (pte_dirty(ptent))
 			mss->shared_dirty += PAGE_SIZE;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/