doc: THP CoW fault no longer allocate THP

Since commit 3917c80280c9 ("thp: change CoW semantics for anon-THP"),
THP CoW page fault is rewritten.  Now it just splits pmd then fallback
to base page fault, it doesn't try to allocate THP anymore.  So it is no
longer counted in THP_FAULT_ALLOC.

Remove the obsolete statement in documentation about THP CoW allocation
to avoid confusion.

Link: http://lkml.kernel.org/r/1592424895-5421-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index ce3e05e41724ae18fb0a3b8d3ae4be79538840a2..d09471aa74434ba6d2cd07e01afc3ab3a503849d 100644 (file)
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1356,8 +1356,8 @@ PAGE_SIZE multiple when read back.
 
          thp_fault_alloc
                Number of transparent hugepages which were allocated to satisfy
-               a page fault, including COW faults. This counter is not present
-               when CONFIG_TRANSPARENT_HUGEPAGE is not set.
+               a page fault. This counter is not present when CONFIG_TRANSPARENT_HUGEPAGE
+                is not set.
 
          thp_collapse_alloc
                Number of transparent hugepages which were allocated to allow

diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst
index 6a233e42be08080f552a3280ecb996cd988d4f29..b2acd0d395ca425f6c7130776db2cb619f303c12 100644 (file)
--- a/Documentation/admin-guide/mm/transhuge.rst
+++ b/Documentation/admin-guide/mm/transhuge.rst
@@ -305,8 +305,7 @@ monitor how successfully the system is providing huge pages for use.
 
 thp_fault_alloc
        is incremented every time a huge page is successfully
-       allocated to handle a page fault. This applies to both the
-       first time a page is faulted and for COW faults.
+       allocated to handle a page fault.
 
 thp_collapse_alloc
        is incremented by khugepaged when it has found