The patch titled
Subject: mm/memory_hotplug: don't check for "all holes" in shrink_zone_span()
has been added to the -mm tree. Its filename is
mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory_hotplug: don't check for "all holes" in shrink_zone_span()
If we have holes, the holes will automatically get detected and removed
once we remove the next bigger/smaller section. The extra checks can go.
Link: http://lkml.kernel.org/r/20191006085646.5768-9-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Cc: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: Damian Tometzki <damian.tometzki@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Halil Pasic <pasic@xxxxxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Jun Yao <yaojun8558363@xxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Pankaj Gupta <pagupta@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Pavel Tatashin <pavel.tatashin@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Rich Felker <dalias@xxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Steve Capper <steve.capper@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 34 +++++++---------------------------
1 file changed, 7 insertions(+), 27 deletions(-)
--- a/mm/memory_hotplug.c~mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span
+++ a/mm/memory_hotplug.c
@@ -411,6 +411,9 @@ static void shrink_zone_span(struct zone
if (pfn) {
zone->zone_start_pfn = pfn;
zone->spanned_pages = zone_end_pfn - pfn;
+ } else {
+ zone->zone_start_pfn = 0;
+ zone->spanned_pages = 0;
}
} else if (zone_end_pfn == end_pfn) {
/*
@@ -423,34 +426,11 @@ static void shrink_zone_span(struct zone
start_pfn);
if (pfn)
zone->spanned_pages = pfn - zone_start_pfn + 1;
+ else {
+ zone->zone_start_pfn = 0;
+ zone->spanned_pages = 0;
+ }
}
-
- /*
- * The section is not biggest or smallest mem_section in the zone, it
- * only creates a hole in the zone. So in this case, we need not
- * change the zone. But perhaps, the zone has only hole data. Thus
- * it check the zone has only hole or not.
- */
- pfn = zone_start_pfn;
- for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) {
- if (unlikely(!pfn_to_online_page(pfn)))
- continue;
-
- if (page_zone(pfn_to_page(pfn)) != zone)
- continue;
-
- /* Skip range to be removed */
- if (pfn >= start_pfn && pfn < end_pfn)
- continue;
-
- /* If we find valid section, we have nothing to do */
- zone_span_writeunlock(zone);
- return;
- }
-
- /* The zone has no valid section */
- zone->zone_start_pfn = 0;
- zone->spanned_pages = 0;
zone_span_writeunlock(zone);
}
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-memory_hotplug-export-generic_online_page.patch
hv_balloon-use-generic_online_page.patch
mm-memory_hotplug-remove-__online_page_free-and-__online_page_increment_counters.patch
mm-memory_hotplug-dont-access-uninitialized-memmaps-in-shrink_pgdat_span.patch
mm-memory_hotplug-dont-access-uninitialized-memmaps-in-shrink_zone_span.patch
mm-memory_hotplug-shrink-zones-when-offlining-memory.patch
mm-memory_hotplug-poison-memmap-in-remove_pfn_range_from_zone.patch
mm-memory_hotplug-we-always-have-a-zone-in-find_smallestbiggest_section_pfn.patch
mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span.patch
mm-memory_hotplug-drop-local-variables-in-shrink_zone_span.patch
mm-memory_hotplug-cleanup-__remove_pages.patch
