On Thu, Jun 24, 2021 at 06:55:13AM -0700, Alexander Duyck wrote: > On Tue, Jun 22, 2021 at 5:34 PM Gavin Shan <gshan@xxxxxxxxxx> wrote: > > > > The macro PAGE_REPORTING_MIN_ORDER is defined as the page reporting > > threshold. It can't be adjusted at runtime. > > > > This introduces a variable (@page_reporting_order) to replace the > > marcro (PAGE_REPORTING_MIN_ORDER). It's also exported so that the > > page reporting order can be adjusted at runtime. > > > > Suggested-by: David Hildenbrand <david@xxxxxxxxxx> > > Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx> > > --- > > Documentation/admin-guide/kernel-parameters.txt | 6 ++++++ > > mm/page_reporting.c | 8 ++++++-- > > mm/page_reporting.h | 5 ++--- > > 3 files changed, 14 insertions(+), 5 deletions(-) > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > > index cb89dbdedc46..566c4b9af3cd 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -3566,6 +3566,12 @@ > > off: turn off poisoning (default) > > on: turn on poisoning > > > > + page_reporting.page_reporting_order= > > + [KNL] Minimal page reporting order > > + Format: <integer> > > + Adjust the minimal page reporting order. The page > > + reporting is disabled when it exceeds (MAX_ORDER-1). > > + > > Based on the issue found by Stephen I think we may need to tweak this > a bit. I think we may want to just default this value to MAX_ORDER. We > can override this value at registration time with the value provided > either by the reporting device or pageblock_order if prdev->order is > not set. > > > diff --git a/mm/page_reporting.c b/mm/page_reporting.c > > index df9c5054e1b4..293a8713ef7c 100644 > > --- a/mm/page_reporting.c > > +++ b/mm/page_reporting.c > > @@ -10,6 +10,10 @@ > > #include "page_reporting.h" > > #include "internal.h" > > > > +unsigned int page_reporting_order = pageblock_order; > > Rather than setting this to pageblock_order directly you can set this > to MAX_ORDER which should be constant. Then we can just add some > checks in page_reporting_register to update it when pageblock_order is > less than page_reporting_order. > > Then in the next patch you could tweak it so that it will use > "prdev->order ? : pageblock_order" instead of just pageblock_order. I like that! Much cleaner ... the patch is in -mm now, I think it's a good idea to drop it and update to use this idea. -- MST
