kernel_optimize_test/mm/memory_hotplug.c
Yasunori Goto 25a6df9525 [PATCH] spanned_pages is not updated at a case of memory hot-add
From: Yasunori Goto <y-goto@jp.fujitsu.com>

If hot-added memory's address is smaller than old area, spanned_pages will
not be updated.  It must be fixed.

example) Old zone_start_pfn = 0x60000, and spanned_pages = 0x10000
         Added new memory's start_pfn = 0x50000, and end_pfn = 0x60000

  new spanned_pages will be still 0x10000 by old code.
  (It should be updated to 0x20000.) Because old_zone_end_pfn will be
  0x70000, and end_pfn smaller than it. So, spanned_pages will not be
  updated.

In current code, spanned_pages is updated only when end_pfn is updated.
But, it should be updated by subtraction between bigger end_pfn and new
zone_start_pfn.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-31 16:27:10 -07:00

143 lines
3.5 KiB
C

/*
* linux/mm/memory_hotplug.c
*
* Copyright (C)
*/
#include <linux/config.h>
#include <linux/stddef.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/interrupt.h>
#include <linux/pagemap.h>
#include <linux/bootmem.h>
#include <linux/compiler.h>
#include <linux/module.h>
#include <linux/pagevec.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/cpu.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include <linux/highmem.h>
#include <linux/vmalloc.h>
#include <asm/tlbflush.h>
extern void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,
unsigned long size);
static void __add_zone(struct zone *zone, unsigned long phys_start_pfn)
{
struct pglist_data *pgdat = zone->zone_pgdat;
int nr_pages = PAGES_PER_SECTION;
int nid = pgdat->node_id;
int zone_type;
zone_type = zone - pgdat->node_zones;
memmap_init_zone(nr_pages, nid, zone_type, phys_start_pfn);
zonetable_add(zone, nid, zone_type, phys_start_pfn, nr_pages);
}
extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
int nr_pages);
static int __add_section(struct zone *zone, unsigned long phys_start_pfn)
{
int nr_pages = PAGES_PER_SECTION;
int ret;
ret = sparse_add_one_section(zone, phys_start_pfn, nr_pages);
if (ret < 0)
return ret;
__add_zone(zone, phys_start_pfn);
return register_new_memory(__pfn_to_section(phys_start_pfn));
}
/*
* Reasonably generic function for adding memory. It is
* expected that archs that support memory hotplug will
* call this function after deciding the zone to which to
* add the new pages.
*/
int __add_pages(struct zone *zone, unsigned long phys_start_pfn,
unsigned long nr_pages)
{
unsigned long i;
int err = 0;
for (i = 0; i < nr_pages; i += PAGES_PER_SECTION) {
err = __add_section(zone, phys_start_pfn + i);
/* We want to keep adding the rest of the
* sections if the first ones already exist
*/
if (err && (err != -EEXIST))
break;
}
return err;
}
EXPORT_SYMBOL_GPL(__add_pages);
static void grow_zone_span(struct zone *zone,
unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long old_zone_end_pfn;
zone_span_writelock(zone);
old_zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
if (start_pfn < zone->zone_start_pfn)
zone->zone_start_pfn = start_pfn;
zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
zone->zone_start_pfn;
zone_span_writeunlock(zone);
}
static void grow_pgdat_span(struct pglist_data *pgdat,
unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long old_pgdat_end_pfn =
pgdat->node_start_pfn + pgdat->node_spanned_pages;
if (start_pfn < pgdat->node_start_pfn)
pgdat->node_start_pfn = start_pfn;
pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
pgdat->node_start_pfn;
}
int online_pages(unsigned long pfn, unsigned long nr_pages)
{
unsigned long i;
unsigned long flags;
unsigned long onlined_pages = 0;
struct zone *zone;
/*
* This doesn't need a lock to do pfn_to_page().
* The section can't be removed here because of the
* memory_block->state_sem.
*/
zone = page_zone(pfn_to_page(pfn));
pgdat_resize_lock(zone->zone_pgdat, &flags);
grow_zone_span(zone, pfn, pfn + nr_pages);
grow_pgdat_span(zone->zone_pgdat, pfn, pfn + nr_pages);
pgdat_resize_unlock(zone->zone_pgdat, &flags);
for (i = 0; i < nr_pages; i++) {
struct page *page = pfn_to_page(pfn + i);
online_page(page);
onlined_pages++;
}
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
setup_per_zone_pages_min();
return 0;
}