diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-07-26 15:26:35 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-26 16:19:19 -0700 |
| commit | e496cf3d782135c1cca0d154d4b924517ff58de0 (patch) | |
| tree | 884ae0082c0b344dd9200b28ca087a3cc0973fed /mm/Kconfig | |
| parent | f3f0e1d2150b2b99da2cbdfaad000089efe9bf30 (diff) | |
| download | lwn-e496cf3d782135c1cca0d154d4b924517ff58de0.tar.gz lwn-e496cf3d782135c1cca0d154d4b924517ff58de0.zip | |
thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
For file mappings, we don't deposit page tables on THP allocation
because it's not strictly required to implement split_huge_pmd(): we can
just clear pmd and let following page faults to reconstruct the page
table.
But Power makes use of deposited page table to address MMU quirk.
Let's hide THP page cache, including huge tmpfs, under separate config
option, so it can be forbidden on Power.
We can revert the patch later once solution for Power found.
Link: http://lkml.kernel.org/r/1466021202-61880-36-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 3e2daef3c946..3c81803b00a3 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -440,6 +440,14 @@ choice endchoice # +# We don't deposit page tables on file THP mapping, +# but Power makes use of them to address MMU quirk. +# +config TRANSPARENT_HUGE_PAGECACHE + def_bool y + depends on TRANSPARENT_HUGEPAGE && !PPC + +# # UP and nommu archs use km based percpu allocator # config NEED_PER_CPU_KM |