From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/page_isolation: simplify return value of start_isolate_page_range() Callers no longer need the number of isolated pageblocks. Let's simplify. Link: https://lkml.kernel.org/r/20200819175957.28465-7-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Cc: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx> 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> --- mm/memory_hotplug.c | 2 +- mm/page_alloc.c | 2 +- mm/page_isolation.c | 7 ++----- 3 files changed, 4 insertions(+), 7 deletions(-) --- a/mm/memory_hotplug.c~mm-page_isolation-simplify-return-value-of-start_isolate_page_range +++ a/mm/memory_hotplug.c @@ -1514,7 +1514,7 @@ int __ref offline_pages(unsigned long st ret = start_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE, MEMORY_OFFLINE | REPORT_FAILURE); - if (ret < 0) { + if (ret) { reason = "failure to isolate range"; goto failed_removal; } --- a/mm/page_alloc.c~mm-page_isolation-simplify-return-value-of-start_isolate_page_range +++ a/mm/page_alloc.c @@ -8468,7 +8468,7 @@ int alloc_contig_range(unsigned long sta ret = start_isolate_page_range(pfn_max_align_down(start), pfn_max_align_up(end), migratetype, 0); - if (ret < 0) + if (ret) return ret; /* --- a/mm/page_isolation.c~mm-page_isolation-simplify-return-value-of-start_isolate_page_range +++ a/mm/page_isolation.c @@ -173,8 +173,7 @@ __first_valid_page(unsigned long pfn, un * (e.g. __offline_pages will need to call it after check for isolated range for * a next retry). * - * Return: the number of isolated pageblocks on success and -EBUSY if any part - * of range cannot be isolated. + * Return: 0 on success and -EBUSY if any part of range cannot be isolated. */ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn, unsigned migratetype, int flags) @@ -182,7 +181,6 @@ int start_isolate_page_range(unsigned lo unsigned long pfn; unsigned long undo_pfn; struct page *page; - int nr_isolate_pageblock = 0; BUG_ON(!IS_ALIGNED(start_pfn, pageblock_nr_pages)); BUG_ON(!IS_ALIGNED(end_pfn, pageblock_nr_pages)); @@ -196,10 +194,9 @@ int start_isolate_page_range(unsigned lo undo_pfn = pfn; goto undo; } - nr_isolate_pageblock++; } } - return nr_isolate_pageblock; + return 0; undo: for (pfn = start_pfn; pfn < undo_pfn; _
