docs/vm: rename documentation files to .rst

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

1 files changed, 0 insertions, 90 deletions

diff --git a/Documentation/vm/page_owner.txt b/Documentation/vm/page_owner.txt
deleted file mode 100644
index 0ed5ab8c7ab4..000000000000
--- a/Documentation/vm/page_owner.txt
+++ /dev/null
@@ -1,90 +0,0 @@
-.. _page_owner:
-
-==================================================
-page owner: Tracking about who allocated each page
-==================================================
-
-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.
-When allocation happens, information about allocation such as call stack
-and order of pages is stored into certain storage for each page.
-When we need to know about status of all pages, we can get and analyze
-this information.
-
-Although we already have tracepoint for tracing page allocation/free,
-using it for analyzing who allocate each page is rather complex. We need
-to enlarge the trace buffer for preventing overlapping until userspace
-program launched. And, launched program continually dump out the trace
-buffer for later analysis and it would change system behviour with more
-possibility rather than just keeping it in memory, so bad for debugging.
-
-page owner can also be used for various purposes. For example, accurate
-fragmentation statistics can be obtained through gfp flag information of
-each page. It is already implemented and activated if page owner is
-enabled. Other usages are more than welcome.
-
-page owner is disabled in default. So, if you'd like to use it, you need
-to add "page_owner=on" into your boot cmdline. If the kernel is built
-with page owner and page owner is disabled in runtime due to no enabling
-boot option, runtime overhead is marginal. If disabled in runtime, it
-doesn't require memory to store owner information, so there is no runtime
-memory overhead. And, page owner inserts just two unlikely branches into
-the page allocator hotpath and if not enabled, then allocation is done
-like as the kernel without page owner. These two unlikely branches should
-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::
-
-   text    data     bss     dec     hex filename
-   40662   1493     644   42799    a72f mm/page_alloc.o
-
-- 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
-   2722      50       0    2772     ad4 mm/page_owner.o
-
-Although, roughly, 4 KB code is added in total, page_alloc.o increase by
-230 bytes and only half of it is in hotpath. Building the kernel with
-page owner and turning it on if needed would be great option to debug
-kernel memory problem.
-
-There is one notice that is caused by implementation detail. page owner
-stores information into the memory from struct page extension. This memory
-is initialized some time later than that page allocator starts in sparse
-memory system, so, until initialization, many pages can be allocated and
-they would have no owner information. To fix it up, these early allocated
-pages are investigated and marked as allocated in initialization phase.
-Although it doesn't mean that they have the right owner information,
-at least, we can tell whether the page is allocated or not,
-more accurately. On 2GB memory x86-64 VM box, 13343 early allocated pages
-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
-=====
-
-1) Build user-space helper::
-
-	cd tools/vm
-	make page_owner_sort
-
-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::
-
-	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``.