The patch titled
Subject: mm: page_alloc: trace type pollution from compaction capturing
has been added to the -mm mm-unstable branch. Its filename is
mm-page_alloc-trace-type-pollution-from-compaction-capturing.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-trace-type-pollution-from-compaction-capturing.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Johannes Weiner <hannes@xxxxxxxxxxx>
Subject: mm: page_alloc: trace type pollution from compaction capturing
Date: Thu, 13 Mar 2025 17:05:33 -0400
When the page allocator places pages of a certain migratetype into blocks
of another type, it has lasting effects on the ability to compact and
defragment down the line. For improving placement and compaction,
visibility into such events is crucial.
The most common case, allocator fallbacks, is already annotated, but
compaction capturing is also allowed to grab pages of a different type.
Extend the tracepoint to cover this case.
Link: https://lkml.kernel.org/r/20250313210647.1314586-3-hannes@xxxxxxxxxxx
Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/mm/page_alloc.c~mm-page_alloc-trace-type-pollution-from-compaction-capturing
+++ a/mm/page_alloc.c
@@ -614,6 +614,10 @@ compaction_capture(struct capture_contro
capc->cc->migratetype != MIGRATE_MOVABLE)
return false;
+ if (migratetype != capc->cc->migratetype)
+ trace_mm_page_alloc_extfrag(page, capc->cc->order, order,
+ capc->cc->migratetype, migratetype);
+
capc->page = page;
return true;
}
_
Patches currently in -mm which might be from hannes@xxxxxxxxxxx are
mm-memcontrol-unshare-v2-only-charge-api-bits-again.patch
mm-memcontrol-move-stray-ratelimit-bits-to-v1.patch
mm-memcontrol-move-memsw-charge-callbacks-to-v1.patch
mm-page_alloc-dont-steal-single-pages-from-biggest-buddy.patch
mm-page_alloc-remove-remnants-of-unlocked-migratetype-updates.patch
mm-page_alloc-group-fallback-functions-together.patch
mm-swap_cgroup-remove-double-initialization-of-locals.patch
mm-compaction-push-watermark-into-compaction_suitable-callers.patch
mm-page_alloc-trace-type-pollution-from-compaction-capturing.patch
mm-page_alloc-defrag_mode.patch
mm-page_alloc-defrag_mode-kswapd-kcompactd-assistance.patch
mm-page_alloc-defrag_mode-kswapd-kcompactd-watermarks.patch
