From c4b382c19c372b307beb23335483a4507357888f Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Wed, 25 Jan 2017 10:52:43 +1100 Subject: mm: prepare for hot-{add, remove} of sub-section ranges Prepare the memory hot-{add,remove} paths for handling sub-section ranges by plumbing the starting page frame and number of pages being handled through arch_{add,remove}_memory() to sparse_{add,remove}_one_section(). This is simply plumbing, small cleanups, and some identifier renames. No intended functional changes. Link: http://lkml.kernel.org/r/148486364991.19694.14012559642668647057.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Cc: Michal Hocko Cc: Vlastimil Babka Cc: Johannes Weiner Cc: Logan Gunthorpe Cc: Mel Gorman Cc: Stephen Bates Signed-off-by: Andrew Morton --- mm/memory_hotplug.c | 85 +++++++++++++++++++++++++++++------------------------ mm/sparse.c | 6 ++-- 2 files changed, 50 insertions(+), 41 deletions(-) (limited to 'mm') diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 1515ed7ee8c3..5700fa216a40 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -468,10 +468,10 @@ static void __meminit grow_pgdat_span(struct pglist_data *pgdat, unsigned long s pgdat->node_start_pfn; } -static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn) +static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn, + unsigned long nr_pages) { struct pglist_data *pgdat = zone->zone_pgdat; - int nr_pages = PAGES_PER_SECTION; int nid = pgdat->node_id; int zone_type; unsigned long flags, pfn; @@ -501,24 +501,21 @@ static int __meminit __add_zone(struct zone *zone, unsigned long phys_start_pfn) } static int __meminit __add_section(int nid, struct zone *zone, - unsigned long phys_start_pfn) + unsigned long pfn, unsigned long nr_pages) { int ret; - if (pfn_valid(phys_start_pfn)) - return -EEXIST; - - ret = sparse_add_one_section(zone, phys_start_pfn); + ret = sparse_add_section(zone, pfn, nr_pages); if (ret < 0) return ret; - ret = __add_zone(zone, phys_start_pfn); + ret = __add_zone(zone, pfn, nr_pages); if (ret < 0) return ret; - return register_new_memory(zone, nid, __pfn_to_section(phys_start_pfn)); + return register_new_memory(zone, nid, __pfn_to_section(pfn)); } /* @@ -527,7 +524,7 @@ static int __meminit __add_section(int nid, struct zone *zone, * call this function after deciding the zone to which to * add the new pages. */ -int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, +int __ref __add_pages(int nid, struct zone *zone, unsigned long pfn, unsigned long nr_pages) { int err = 0, i, start_sec, end_sec; @@ -535,16 +532,12 @@ int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, clear_zone_contiguous(zone); - /* during initialize mem_map, align hot-added range to section */ - start_sec = pfn_to_section_nr(phys_start_pfn); - end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1); - - altmap = to_vmem_altmap((unsigned long) pfn_to_page(phys_start_pfn)); + altmap = to_vmem_altmap((unsigned long) pfn_to_page(pfn)); if (altmap) { /* * Validate altmap is within bounds of the total request */ - if (altmap->base_pfn != phys_start_pfn + if (altmap->base_pfn != pfn || vmem_altmap_offset(altmap) > nr_pages) { pr_warn_once("memory add fail, invalid altmap\n"); err = -EINVAL; @@ -553,8 +546,16 @@ int __ref __add_pages(int nid, struct zone *zone, unsigned long phys_start_pfn, altmap->alloc = 0; } + start_sec = pfn_to_section_nr(pfn); + end_sec = pfn_to_section_nr(pfn + nr_pages - 1); for (i = start_sec; i <= end_sec; i++) { - err = __add_section(nid, zone, section_nr_to_pfn(i)); + unsigned long pfns; + + pfns = min(nr_pages, PAGES_PER_SECTION + - (pfn & ~PAGE_SECTION_MASK)); + err = __add_section(nid, zone, pfn, pfns); + pfn += pfns; + nr_pages -= pfns; /* * EEXIST is finally dealt with by ioresource collision @@ -760,10 +761,10 @@ static void shrink_pgdat_span(struct pglist_data *pgdat, pgdat->node_spanned_pages = 0; } -static void __remove_zone(struct zone *zone, unsigned long start_pfn) +static void __remove_zone(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages) { struct pglist_data *pgdat = zone->zone_pgdat; - int nr_pages = PAGES_PER_SECTION; int zone_type; unsigned long flags; @@ -775,11 +776,10 @@ static void __remove_zone(struct zone *zone, unsigned long start_pfn) pgdat_resize_unlock(zone->zone_pgdat, &flags); } -static int __remove_section(struct zone *zone, struct mem_section *ms, - unsigned long map_offset) +static int __remove_section(struct zone *zone, unsigned long pfn, + unsigned long nr_pages, unsigned long map_offset) { - unsigned long start_pfn; - int scn_nr; + struct mem_section *ms = __nr_to_section(pfn_to_section_nr(pfn)); int ret = -EINVAL; if (!valid_section(ms)) @@ -789,11 +789,9 @@ static int __remove_section(struct zone *zone, struct mem_section *ms, if (ret) return ret; - scn_nr = __section_nr(ms); - start_pfn = section_nr_to_pfn(scn_nr); - __remove_zone(zone, start_pfn); + __remove_zone(zone, pfn, nr_pages); - sparse_remove_one_section(zone, ms, map_offset); + sparse_remove_section(zone, ms, pfn, nr_pages, map_offset); return 0; } @@ -808,16 +806,15 @@ static int __remove_section(struct zone *zone, struct mem_section *ms, * sure that pages are marked reserved and zones are adjust properly by * calling offline_pages(). */ -int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, +int __remove_pages(struct zone *zone, unsigned long pfn, unsigned long nr_pages) { - unsigned long i; unsigned long map_offset = 0; - int sections_to_remove, ret = 0; + int i, start_sec, end_sec, ret = 0; /* In the ZONE_DEVICE case device driver owns the memory region */ if (is_dev_zone(zone)) { - struct page *page = pfn_to_page(phys_start_pfn); + struct page *page = pfn_to_page(pfn); struct vmem_altmap *altmap; altmap = to_vmem_altmap((unsigned long) page); @@ -826,7 +823,7 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, } else { resource_size_t start, size; - start = phys_start_pfn << PAGE_SHIFT; + start = pfn << PAGE_SHIFT; size = nr_pages * PAGE_SIZE; ret = release_mem_region_adjustable(&iomem_resource, start, @@ -842,16 +839,26 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, clear_zone_contiguous(zone); /* - * We can only remove entire sections + * Only ZONE_DEVICE memory is enabled to remove + * section-unaligned ranges. See register_new_memory() which + * assumes section alignment and is skipped for ZONE_DEVICE + * ranges. */ - BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK); - BUG_ON(nr_pages % PAGES_PER_SECTION); + if (!is_dev_zone(zone) && ((pfn | nr_pages) & ~PAGE_SECTION_MASK)) { + WARN(1, "section unaligned removal not supported\n"); + return -EINVAL; + } - sections_to_remove = nr_pages / PAGES_PER_SECTION; - for (i = 0; i < sections_to_remove; i++) { - unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION; + start_sec = pfn_to_section_nr(pfn); + end_sec = pfn_to_section_nr(pfn + nr_pages - 1); + for (i = start_sec; i <= end_sec; i++) { + unsigned long pfns; - ret = __remove_section(zone, __pfn_to_section(pfn), map_offset); + pfns = min(nr_pages, PAGES_PER_SECTION + - (pfn & ~PAGE_SECTION_MASK)); + ret = __remove_section(zone, pfn, pfns, map_offset); + pfn += pfns; + nr_pages -= pfns; map_offset = 0; if (ret) break; diff --git a/mm/sparse.c b/mm/sparse.c index 2f571e371ec1..ba5b30d6e076 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -753,7 +753,8 @@ static void free_map_bootmem(struct page *memmap) #endif /* CONFIG_MEMORY_HOTREMOVE */ #endif /* CONFIG_SPARSEMEM_VMEMMAP */ -int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn) +int __meminit sparse_add_section(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages) { unsigned long section_nr = pfn_to_section_nr(start_pfn); struct pglist_data *pgdat = zone->zone_pgdat; @@ -855,7 +856,8 @@ static void free_section_usage(struct page *memmap, free_map_bootmem(memmap); } -void sparse_remove_one_section(struct zone *zone, struct mem_section *ms, +void sparse_remove_section(struct zone *zone, struct mem_section *ms, + unsigned long pfn, unsigned long nr_pages, unsigned long map_offset) { unsigned long flags; -- cgit v1.2.3