On 20.02.24 10:03, David Hildenbrand wrote:
On 16.02.24 18:04, Zi Yan wrote:
From: Zi Yan <ziy@xxxxxxxxxx>
migrate_pages() supports >0 order folio migration and during compaction,
even if compaction_alloc() cannot provide >0 order free pages,
migrate_pages() can split the source page and try to migrate the base
pages from the split. It can be a baseline and start point for adding
support for compacting >0 order folios.
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
Suggested-by: Huang Ying <ying.huang@xxxxxxxxx>
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Tested-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Tested-by: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Adam Manzanares <a.manzanares@xxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yin Fengwei <fengwei.yin@xxxxxxxxx>
---
mm/compaction.c | 66 ++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 52 insertions(+), 14 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index cc801ce099b4..aa6aad805c4d 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -816,6 +816,21 @@ static bool too_many_isolated(struct compact_control *cc)
return too_many;
}
+/*
Can't you add these comments to the respective checks? Like
static bool skip_isolation_on_order(int order, int target_order)
{
/*
* Unless we are performing global compaction (targert_order <
* 0), skip any folios that are larger than the target order: we
* wouldn't be here if we'd have a free folio with the desired
* target_order, so migrating this folio would likely fail
* later.
*/
if (target_order != -1 && order >= target_order)
return true;
I just stumbled over "is_via_compact_memory", likely that should be used
instead of the "!= -1 check.
--
Cheers,
David / dhildenb
