[PATCH v2 03/10] mm/memory_hotplug: simplify page offlining
From: David Hildenbrand <hidden>
Date: 2020-08-19 18:01:32
Also in:
lkml
Subsystem:
memory hot(un)plug, memory management, the rest · Maintainers:
David Hildenbrand, Oscar Salvador, Andrew Morton, Linus Torvalds
We make sure that we cannot have any memory holes right at the beginning of offline_pages(). We no longer need walk_system_ram_range() and can call test_pages_isolated() and __offline_isolated_pages() directly. offlined_pages always corresponds to nr_pages, so we can simplify that. Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Wei Yang <redacted> Cc: Baoquan He <redacted> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: David Hildenbrand <redacted> --- mm/memory_hotplug.c | 46 ++++++++++----------------------------------- 1 file changed, 10 insertions(+), 36 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 6856702af68d9..50aa5df696e9d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c@@ -1373,28 +1373,6 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) return ret; } -/* Mark all sections offline and remove all free pages from the buddy. */ -static int -offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages, - void *data) -{ - unsigned long *offlined_pages = (unsigned long *)data; - - *offlined_pages += __offline_isolated_pages(start, start + nr_pages); - return 0; -} - -/* - * Check all pages in range, recorded as memory resource, are isolated. - */ -static int -check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages, - void *data) -{ - return test_pages_isolated(start_pfn, start_pfn + nr_pages, - MEMORY_OFFLINE); -} - static int __init cmdline_parse_movable_node(char *p) { movable_node_enabled = true;
@@ -1481,7 +1459,7 @@ static int count_system_ram_pages_cb(unsigned long start_pfn, int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages) { const unsigned long end_pfn = start_pfn + nr_pages; - unsigned long pfn, system_ram_pages = 0, offlined_pages = 0; + unsigned long pfn, system_ram_pages = 0; int ret, node, nr_isolate_pageblock; unsigned long flags; struct zone *zone;
@@ -1579,16 +1557,12 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages) reason = "failure to dissolve huge pages"; goto failed_removal_isolated; } - /* check again */ - ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, - NULL, check_pages_isolated_cb); - } while (ret); - - /* Ok, all of our target is isolated. - We cannot do rollback at this point. */ - walk_system_ram_range(start_pfn, end_pfn - start_pfn, - &offlined_pages, offline_isolated_pages_cb); - pr_info("Offlined Pages %ld\n", offlined_pages); + } while (test_pages_isolated(start_pfn, end_pfn, MEMORY_OFFLINE)); + + /* Mark all sections offline and remove free pages from the buddy. */ + __offline_isolated_pages(start_pfn, end_pfn); + pr_info("Offlined Pages %ld\n", nr_pages); + /* * Onlining will reset pagetype flags and makes migrate type * MOVABLE, so just need to decrease the number of isolated
@@ -1599,11 +1573,11 @@ int __ref offline_pages(unsigned long start_pfn, unsigned long nr_pages) spin_unlock_irqrestore(&zone->lock, flags); /* removal success */ - adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages); - zone->present_pages -= offlined_pages; + adjust_managed_page_count(pfn_to_page(start_pfn), -nr_pages); + zone->present_pages -= nr_pages; pgdat_resize_lock(zone->zone_pgdat, &flags); - zone->zone_pgdat->node_present_pages -= offlined_pages; + zone->zone_pgdat->node_present_pages -= nr_pages; pgdat_resize_unlock(zone->zone_pgdat, &flags); init_per_zone_wmark_min();
--
2.26.2