From b6c88d3b9d38f9448e0fcf44847a075ea81d5ca2 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Mon, 23 Sep 2019 15:35:49 -0700 Subject: [PATCH] drivers/base/memory.c: don't store end_section_nr in memory blocks Each memory block spans the same amount of sections/pages/bytes. The size is determined before the first memory block is created. No need to store what we can easily calculate - and the calculations even look simpler now. Michal brought up the idea of variable-sized memory blocks. However, if we ever implement something like this, we will need an API compatibility switch and reworks at various places (most code assumes a fixed memory block size). So let's cleanup what we have right now. While at it, fix the variable naming in register_mem_sect_under_node() - we no longer talk about a single section. Link: http://lkml.kernel.org/r/20190809110200.2746-1-david@redhat.com Signed-off-by: David Hildenbrand Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Pavel Tatashin Cc: Michal Hocko Cc: Dan Williams Cc: Oscar Salvador Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/base/memory.c | 1 - drivers/base/node.c | 10 +++++----- include/linux/memory.h | 1 - mm/memory_hotplug.c | 2 +- 4 files changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 763154c..6bea4f3 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -656,7 +656,6 @@ static int init_memory_block(struct memory_block **memory, return -ENOMEM; mem->start_section_nr = block_id * sections_per_block; - mem->end_section_nr = mem->start_section_nr + sections_per_block - 1; mem->state = state; start_pfn = section_nr_to_pfn(mem->start_section_nr); mem->phys_device = arch_get_memory_phys_device(start_pfn); diff --git a/drivers/base/node.c b/drivers/base/node.c index 840c95b..257449cf 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -756,13 +756,13 @@ static int __ref get_nid_for_pfn(unsigned long pfn) static int register_mem_sect_under_node(struct memory_block *mem_blk, void *arg) { + unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE; + unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); + unsigned long end_pfn = start_pfn + memory_block_pfns - 1; int ret, nid = *(int *)arg; - unsigned long pfn, sect_start_pfn, sect_end_pfn; + unsigned long pfn; - sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); - sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); - sect_end_pfn += PAGES_PER_SECTION - 1; - for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { + for (pfn = start_pfn; pfn <= end_pfn; pfn++) { int page_nid; /* diff --git a/include/linux/memory.h b/include/linux/memory.h index b3d9df0..0ebb105 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -25,7 +25,6 @@ struct memory_block { unsigned long start_section_nr; - unsigned long end_section_nr; unsigned long state; /* serialized by the dev->lock */ int section_count; /* serialized by mem_sysfs_mutex */ int online_type; /* for passing data to online routine */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5b88119..3706a13 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1654,7 +1654,7 @@ static int check_memblock_offlined_cb(struct memory_block *mem, void *arg) phys_addr_t beginpa, endpa; beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr)); - endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1; + endpa = beginpa + memory_block_size_bytes() - 1; pr_warn("removing memory fails, because memory [%pa-%pa] is onlined\n", &beginpa, &endpa); -- 2.7.4