[PATCHv3, RESEND 0/8] thp/khugepaged improvements and CoW semantics

From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: akpm@linux-foundation.org, Andrea Arcangeli <aarcange@redhat.com>
Cc: Zi Yan <ziy@nvidia.com>, Yang Shi <yang.shi@linux.alibaba.com>,
	Ralph Campbell <rcampbell@nvidia.com>,
	John Hubbard <jhubbard@nvidia.com>,
	William Kucharski <william.kucharski@oracle.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org,
	"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: [PATCHv3, RESEND 0/8] thp/khugepaged improvements and CoW semantics
Date: Mon, 13 Apr 2020 15:52:12 +0300	[thread overview]
Message-ID: <20200413125220.663-1-kirill.shutemov@linux.intel.com> (raw)

The patchset adds khugepaged selftest (anon-THP only for now), expands
cases khugepaged can handle and switches anon-THP copy-on-write handling
to 4k.

Please review and consider applying.

v3:
 - Fix handling compound pages in swap cache;
 - Rework swaped vs. referenced check;
 - Fix refcounting for compound pages;
 - Drop Reviewed-by/Acked-by as patchset changed non-trivially;
 - Typos;
v2:
 - Fix race in compound page handling;
 - Add one more test-case for compound page case;
 - Rework LRU add cache draining;
 - Typos;

Kirill A. Shutemov (8):
  khugepaged: Add self test
  khugepaged: Do not stop collapse if less than half PTEs are referenced
  khugepaged: Drain all LRU caches before scanning pages
  khugepaged: Drain LRU add pagevec after swapin
  khugepaged: Allow to collapse a page shared across fork
  khugepaged: Allow to collapse PTE-mapped compound pages
  thp: Change CoW semantics for anon-THP
  khugepaged: Introduce 'max_ptes_shared' tunable

 Documentation/admin-guide/mm/transhuge.rst |   7 +
 include/trace/events/huge_memory.h         |   3 +-
 mm/huge_memory.c                           | 249 +-----
 mm/khugepaged.c                            | 218 +++--
 tools/testing/selftests/vm/Makefile        |   1 +
 tools/testing/selftests/vm/khugepaged.c    | 982 +++++++++++++++++++++
 6 files changed, 1174 insertions(+), 286 deletions(-)
 create mode 100644 tools/testing/selftests/vm/khugepaged.c

-- 
2.26.0