diff options
| author | Huang Ying <[email protected]> | 2018-08-17 15:49:41 -0700 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2018-08-17 16:20:32 -0700 |
| commit | 14fef28414c365a979311821bbf1018a8290cc0f (patch) | |
| tree | acf988e3dce9ab19c6285a56d8266cf7698b3209 | |
| parent | 2a3cb8baef71e4dad4a6ec17f5f0db9e05f46a01 (diff) | |
mm, swap: make CONFIG_THP_SWAP depend on CONFIG_SWAP
CONFIG_THP_SWAP should depend on CONFIG_SWAP, because it's unreasonable
to optimize swapping for THP (Transparent Huge Page) without basic
swapping support.
In original code, when CONFIG_SWAP=n and CONFIG_THP_SWAP=y,
split_swap_cluster() will not be built because it is in swapfile.c, but
it will be called in huge_memory.c. This doesn't trigger a build error
in practice because the call site is enclosed by PageSwapCache(), which
is defined to be constant 0 when CONFIG_SWAP=n. But this is fragile and
should be fixed.
The comments are fixed too to reflect the latest progress.
Link: http://lkml.kernel.org/r/[email protected]
Fixes: 38d8b4e6bdc8 ("mm, THP, swap: delay splitting THP during swap out")
Signed-off-by: "Huang, Ying" <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
Reviewed-by: Naoya Horiguchi <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Shaohua Li <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Zi Yan <[email protected]>
Cc: Daniel Jordan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
| -rw-r--r-- | mm/Kconfig | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index adfeae4decb4..a550635ea5c3 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -419,10 +419,11 @@ config ARCH_WANTS_THP_SWAP config THP_SWAP def_bool y - depends on TRANSPARENT_HUGEPAGE && ARCH_WANTS_THP_SWAP + depends on TRANSPARENT_HUGEPAGE && ARCH_WANTS_THP_SWAP && SWAP help Swap transparent huge pages in one piece, without splitting. - XXX: For now this only does clustered swap space allocation. + XXX: For now, swap cluster backing transparent huge page + will be split after swapout. For selection by architectures with reasonable THP sizes. |