The patch titled
Subject: mm/page_alloc: simplify __offline_isolated_pages()
has been added to the -mm tree. Its filename is
mm-page_alloc-simplify-__offline_isolated_pages.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-page_alloc-simplify-__offline_isolated_pages.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_alloc-simplify-__offline_isolated_pages.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/page_alloc: simplify __offline_isolated_pages()
offline_pages() is the only user. __offline_isolated_pages() never gets
called with ranges that contain memory holes and we no longer care about
the return value. Drop the return value handling and all pfn_valid()
checks.
Update the documentation.
Link: https://lkml.kernel.org/r/20200819175957.28465-5-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx>
Cc: Baoquan He <bhe@xxxxxxxxxx>
Cc: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Charan Teja Reddy <charante@xxxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michel Lespinasse <walken@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/memory_hotplug.h | 4 ++--
mm/page_alloc.c | 27 ++++-----------------------
2 files changed, 6 insertions(+), 25 deletions(-)
--- a/include/linux/memory_hotplug.h~mm-page_alloc-simplify-__offline_isolated_pages
+++ a/include/linux/memory_hotplug.h
@@ -103,8 +103,8 @@ extern int online_pages(unsigned long pf
int online_type, int nid);
extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
unsigned long end_pfn);
-extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
- unsigned long end_pfn);
+extern void __offline_isolated_pages(unsigned long start_pfn,
+ unsigned long end_pfn);
typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
--- a/mm/page_alloc.c~mm-page_alloc-simplify-__offline_isolated_pages
+++ a/mm/page_alloc.c
@@ -8685,35 +8685,21 @@ void zone_pcp_reset(struct zone *zone)
#ifdef CONFIG_MEMORY_HOTREMOVE
/*
- * All pages in the range must be in a single zone and isolated
- * before calling this.
+ * All pages in the range must be in a single zone, must not contain holes,
+ * must span full sections, and must be isolated before calling this function.
*/
-unsigned long
-__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
+void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
{
+ unsigned long pfn = start_pfn;
struct page *page;
struct zone *zone;
unsigned int order;
- unsigned long pfn;
unsigned long flags;
- unsigned long offlined_pages = 0;
-
- /* find the first valid pfn */
- for (pfn = start_pfn; pfn < end_pfn; pfn++)
- if (pfn_valid(pfn))
- break;
- if (pfn == end_pfn)
- return offlined_pages;
offline_mem_sections(pfn, end_pfn);
zone = page_zone(pfn_to_page(pfn));
spin_lock_irqsave(&zone->lock, flags);
- pfn = start_pfn;
while (pfn < end_pfn) {
- if (!pfn_valid(pfn)) {
- pfn++;
- continue;
- }
page = pfn_to_page(pfn);
/*
* The HWPoisoned page may be not in buddy system, and
@@ -8721,7 +8707,6 @@ __offline_isolated_pages(unsigned long s
*/
if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
pfn++;
- offlined_pages++;
continue;
}
/*
@@ -8732,20 +8717,16 @@ __offline_isolated_pages(unsigned long s
BUG_ON(page_count(page));
BUG_ON(PageBuddy(page));
pfn++;
- offlined_pages++;
continue;
}
BUG_ON(page_count(page));
BUG_ON(!PageBuddy(page));
order = page_order(page);
- offlined_pages += 1 << order;
del_page_from_free_list(page, zone, order);
pfn += (1 << order);
}
spin_unlock_irqrestore(&zone->lock, flags);
-
- return offlined_pages;
}
#endif
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-page_alloc-tweak-comments-in-has_unmovable_pages.patch
mm-page_isolation-exit-early-when-pageblock-is-isolated-in-set_migratetype_isolate.patch
mm-page_isolation-drop-warn_on_once-in-set_migratetype_isolate.patch
mm-page_isolation-cleanup-set_migratetype_isolate.patch
virtio-mem-dont-special-case-zone_movable.patch
mm-document-semantics-of-zone_movable.patch
mm-memory_hotplug-inline-__offline_pages-into-offline_pages.patch
mm-memory_hotplug-enforce-section-granularity-when-onlining-offlining.patch
mm-memory_hotplug-simplify-page-offlining.patch
mm-page_alloc-simplify-__offline_isolated_pages.patch
mm-memory_hotplug-drop-nr_isolate_pageblock-in-offline_pages.patch
mm-page_isolation-simplify-return-value-of-start_isolate_page_range.patch
mm-memory_hotplug-simplify-page-onlining.patch
mm-page_alloc-drop-stale-pageblock-comment-in-memmap_init_zone.patch
mm-pass-migratetype-into-memmap_init_zone-and-move_pfn_range_to_zone.patch
mm-memory_hotplug-mark-pageblocks-migrate_isolate-while-onlining-memory.patch
