From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/memory_hotplug: drop valid_start/valid_end from test_pages_in_a_zone() The callers are only interested in the actual zone, they don't care about boundaries. Return the zone instead to simplify. Link: http://lkml.kernel.org/r/20200110183308.11849-1-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/base/memory.c | 9 ++++----- include/linux/memory_hotplug.h | 4 ++-- mm/memory_hotplug.c | 31 +++++++++---------------------- 3 files changed, 15 insertions(+), 29 deletions(-) --- a/drivers/base/memory.c~mm-memory_hotplug-drop-valid_start-valid_end-from-test_pages_in_a_zone +++ a/drivers/base/memory.c @@ -376,7 +376,6 @@ static ssize_t valid_zones_show(struct d struct memory_block *mem = to_memory_block(dev); unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr); unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block; - unsigned long valid_start_pfn, valid_end_pfn; struct zone *default_zone; int nid; @@ -389,11 +388,11 @@ static ssize_t valid_zones_show(struct d * The block contains more than one zone can not be offlined. * This can happen e.g. for ZONE_DMA and ZONE_DMA32 */ - if (!test_pages_in_a_zone(start_pfn, start_pfn + nr_pages, - &valid_start_pfn, &valid_end_pfn)) + default_zone = test_pages_in_a_zone(start_pfn, + start_pfn + nr_pages); + if (!default_zone) return sprintf(buf, "none\n"); - start_pfn = valid_start_pfn; - strcat(buf, page_zone(pfn_to_page(start_pfn))->name); + strcat(buf, default_zone->name); goto out; } --- a/include/linux/memory_hotplug.h~mm-memory_hotplug-drop-valid_start-valid_end-from-test_pages_in_a_zone +++ a/include/linux/memory_hotplug.h @@ -96,8 +96,8 @@ extern int add_one_highpage(struct page /* VM interface that may be used by firmware interface */ extern int online_pages(unsigned long pfn, unsigned long nr_pages, int online_type, int nid); -extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, - unsigned long *valid_start, unsigned long *valid_end); +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); --- a/mm/memory_hotplug.c~mm-memory_hotplug-drop-valid_start-valid_end-from-test_pages_in_a_zone +++ a/mm/memory_hotplug.c @@ -1172,14 +1172,13 @@ bool is_mem_section_removable(unsigned l } /* - * Confirm all pages in a range [start, end) belong to the same zone. - * When true, return its valid [start, end). + * Confirm all pages in a range [start, end) belong to the same zone (skipping + * memory holes). When true, return the zone. */ -int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, - unsigned long *valid_start, unsigned long *valid_end) +struct zone *test_pages_in_a_zone(unsigned long start_pfn, + unsigned long end_pfn) { unsigned long pfn, sec_end_pfn; - unsigned long start, end; struct zone *zone = NULL; struct page *page; int i; @@ -1200,24 +1199,15 @@ int test_pages_in_a_zone(unsigned long s continue; /* Check if we got outside of the zone */ if (zone && !zone_spans_pfn(zone, pfn + i)) - return 0; + return NULL; page = pfn_to_page(pfn + i); if (zone && page_zone(page) != zone) - return 0; - if (!zone) - start = pfn + i; + return NULL; zone = page_zone(page); - end = pfn + MAX_ORDER_NR_PAGES; } } - if (zone) { - *valid_start = start; - *valid_end = min(end, end_pfn); - return 1; - } else { - return 0; - } + return zone; } /* @@ -1462,7 +1452,6 @@ static int __ref __offline_pages(unsigne unsigned long offlined_pages = 0; int ret, node, nr_isolate_pageblock; unsigned long flags; - unsigned long valid_start, valid_end; struct zone *zone; struct memory_notify arg; char *reason; @@ -1487,14 +1476,12 @@ static int __ref __offline_pages(unsigne /* This makes hotplug much easier...and readable. we assume this for now. .*/ - if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, - &valid_end)) { + zone = test_pages_in_a_zone(start_pfn, end_pfn); + if (!zone) { ret = -EINVAL; reason = "multizone range"; goto failed_removal; } - - zone = page_zone(pfn_to_page(valid_start)); node = zone_to_nid(zone); /* set above range as isolated */ _
