Documentation/admin-guide/mm/transhuge.rst (originally in Documentation/vm/transhuge.txt)
states that TRANSPARENT_HUGEPAGE_MADVISE is the default option for THP config:
"
madvise
will enter direct reclaim like ``always`` but only for regions
that are have used madvise(MADV_HUGEPAGE). This is the default
behaviour.
"
This patch changes mm/Kconfig to reflect that fact, accordingly.
Besides keeping consistency between documentation and the code behavior,
other reasons to perform this minor adjustment are noted at:
https://bugzilla.redhat.com/show_bug.cgi?id=1772133
Signed-off-by: Rafael Aquini <[email protected]>
---
mm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/Kconfig b/mm/Kconfig
index a5dae9a7eb51..c12a559aa1e5 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -385,7 +385,7 @@ config TRANSPARENT_HUGEPAGE
choice
prompt "Transparent Hugepage Support sysfs defaults"
depends on TRANSPARENT_HUGEPAGE
- default TRANSPARENT_HUGEPAGE_ALWAYS
+ default TRANSPARENT_HUGEPAGE_MADVISE
help
Selects the sysfs defaults for Transparent Hugepage Support.
--
2.17.2
On Mon, Nov 18, 2019 at 10:01:02PM -0500, Rafael Aquini wrote:
> Documentation/admin-guide/mm/transhuge.rst (originally in Documentation/vm/transhuge.txt)
> states that TRANSPARENT_HUGEPAGE_MADVISE is the default option for THP config:
>
> "
> madvise
> will enter direct reclaim like ``always`` but only for regions
> that are have used madvise(MADV_HUGEPAGE). This is the default
> behaviour.
> "
>
> This patch changes mm/Kconfig to reflect that fact, accordingly.
No. You've read it incorrectly.
The documentation describes default behaviour wrt defragmentaton ("defrag"
file), not page fault ("enabled" file). We don't have any Kconfig option
to set default behaviour for "defrag".
> Besides keeping consistency between documentation and the code behavior,
> other reasons to perform this minor adjustment are noted at:
> https://bugzilla.redhat.com/show_bug.cgi?id=1772133
>
> Signed-off-by: Rafael Aquini <[email protected]>
> ---
> mm/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/Kconfig b/mm/Kconfig
> index a5dae9a7eb51..c12a559aa1e5 100644
> --- a/mm/Kconfig
> +++ b/mm/Kconfig
> @@ -385,7 +385,7 @@ config TRANSPARENT_HUGEPAGE
> choice
> prompt "Transparent Hugepage Support sysfs defaults"
> depends on TRANSPARENT_HUGEPAGE
> - default TRANSPARENT_HUGEPAGE_ALWAYS
> + default TRANSPARENT_HUGEPAGE_MADVISE
> help
> Selects the sysfs defaults for Transparent Hugepage Support.
>
> --
> 2.17.2
>
>
--
Kirill A. Shutemov
On Tue, Nov 19, 2019 at 01:47:41PM +0300, Kirill A. Shutemov wrote:
> On Mon, Nov 18, 2019 at 10:01:02PM -0500, Rafael Aquini wrote:
> > Documentation/admin-guide/mm/transhuge.rst (originally in Documentation/vm/transhuge.txt)
> > states that TRANSPARENT_HUGEPAGE_MADVISE is the default option for THP config:
> >
> > "
> > madvise
> > will enter direct reclaim like ``always`` but only for regions
> > that are have used madvise(MADV_HUGEPAGE). This is the default
> > behaviour.
> > "
> >
> > This patch changes mm/Kconfig to reflect that fact, accordingly.
>
> No. You've read it incorrectly.
>
Fair enough.
I'll reform the log message then, and repost.
> The documentation describes default behaviour wrt defragmentaton ("defrag"
> file), not page fault ("enabled" file). We don't have any Kconfig option
> to set default behaviour for "defrag".
>
> > Besides keeping consistency between documentation and the code behavior,
> > other reasons to perform this minor adjustment are noted at:
> > https://bugzilla.redhat.com/show_bug.cgi?id=1772133
> >
> > Signed-off-by: Rafael Aquini <[email protected]>
> > ---
> > mm/Kconfig | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/mm/Kconfig b/mm/Kconfig
> > index a5dae9a7eb51..c12a559aa1e5 100644
> > --- a/mm/Kconfig
> > +++ b/mm/Kconfig
> > @@ -385,7 +385,7 @@ config TRANSPARENT_HUGEPAGE
> > choice
> > prompt "Transparent Hugepage Support sysfs defaults"
> > depends on TRANSPARENT_HUGEPAGE
> > - default TRANSPARENT_HUGEPAGE_ALWAYS
> > + default TRANSPARENT_HUGEPAGE_MADVISE
> > help
> > Selects the sysfs defaults for Transparent Hugepage Support.
> >
> > --
> > 2.17.2
> >
> >
>
> --
> Kirill A. Shutemov
>