x86: mremap speedup - Enable HAVE_MOVE_PUD

HAVE_MOVE_PUD enables remapping pages at the PUD level if both the
source and destination addresses are PUD-aligned.

With HAVE_MOVE_PUD enabled it can be inferred that there is
approximately a 13x improvement in performance on x86.  (See data
below).

------- Test Results ---------

The following results were obtained using a 5.4 kernel, by remapping
a PUD-aligned, 1GB sized region to a PUD-aligned destination.
The results from 10 iterations of the test are given below:

Total mremap times for 1GB data on x86. All times are in nanoseconds.

  Control        HAVE_MOVE_PUD

  180394         15089
  235728         14056
  238931         25741
  187330         13838
  241742         14187
  177925         14778
  182758         14728
  160872         14418
  205813         15107
  245722         13998

  205721.5       15594    <-- Mean time in nanoseconds

A 1GB mremap completion time drops from ~205 microseconds
to ~15 microseconds on x86. (~13x speed up).

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Kalesh Singh <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Acked-by: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Anshuman Khandual <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Brian Geffon <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Gavin Shan <[email protected]>
Cc: Hassan Naveed <[email protected]>
Cc: Jia He <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Krzysztof Kozlowski <[email protected]>
Cc: Lokesh Gidra <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Masahiro Yamada <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Mina Almasry <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: Ram Pai <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Sandipan Das <[email protected]>
Cc: SeongJae Park <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Steven Price <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index fbf26e0f7a6a..46393177ce73 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -199,6 +199,7 @@ config X86
 	select HAVE_MIXED_BREAKPOINTS_REGS
 	select HAVE_MOD_ARCH_SPECIFIC
 	select HAVE_MOVE_PMD
+	select HAVE_MOVE_PUD
 	select HAVE_NMI
 	select HAVE_OPROFILE
 	select HAVE_OPTPROBES