docs/vm: page_owner: convert to ReST format

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/vm/page_owner.txt

+.. _page_owner:
+
+==================================================
 page owner: Tracking about who allocated each page
------------------------------------------------------------
+==================================================
 
-* Introduction
+Introduction
+============
 
 page owner is for the tracking about who allocated each page.
 It can be used to debug memory leak or to find a memory hogger.
@@ -34,11 +38,13 @@ not affect to allocation performance, especially if the static keys jump
 label patching functionality is available. Following is the kernel's code
 size change due to this facility.
 
-- Without page owner
+- Without page owner::
+
    text    data     bss     dec     hex filename
    40662   1493     644   42799    a72f mm/page_alloc.o
 
-- With page owner
+- With page owner::
+
    text    data     bss     dec     hex filename
    40892   1493     644   43029    a815 mm/page_alloc.o
    1427      24       8    1459     5b3 mm/page_ext.o
@@ -62,21 +68,23 @@ are catched and marked, although they are mostly allocated from struct
 page extension feature. Anyway, after that, no page is left in
 un-tracking state.
 
-* Usage
+Usage
+=====
+
+1) Build user-space helper::
 
-1) Build user-space helper
 	cd tools/vm
 	make page_owner_sort
 
-2) Enable page owner
-	Add "page_owner=on" to boot cmdline.
+2) Enable page owner: add "page_owner=on" to boot cmdline.
 
 3) Do the job what you want to debug
 
-4) Analyze information from page owner
+4) Analyze information from page owner::
+
 	cat /sys/kernel/debug/page_owner > page_owner_full.txt
 	grep -v ^PFN page_owner_full.txt > page_owner.txt
 	./page_owner_sort page_owner.txt sorted_page_owner.txt
 
    See the result about who allocated each page
-	in the sorted_page_owner.txt.
+   in the ``sorted_page_owner.txt``.