mm: remove the memory isolate notifier

Luckily, we have no users left, so we can get rid of it.  Cleanup
set_migratetype_isolate() a little bit.

Link: http://lkml.kernel.org/r/20191114131911.11783-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Qian Cai <cai@lca.pw>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Hildenbrand 2020-01-30 22:14:01 -08:00 committed by Linus Torvalds
parent 3f1353552e
commit 3f9903b9ca
3 changed files with 4 additions and 80 deletions

View file

@ -70,20 +70,6 @@ void unregister_memory_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(unregister_memory_notifier);
static ATOMIC_NOTIFIER_HEAD(memory_isolate_chain);
int register_memory_isolate_notifier(struct notifier_block *nb)
{
return atomic_notifier_chain_register(&memory_isolate_chain, nb);
}
EXPORT_SYMBOL(register_memory_isolate_notifier);
void unregister_memory_isolate_notifier(struct notifier_block *nb)
{
atomic_notifier_chain_unregister(&memory_isolate_chain, nb);
}
EXPORT_SYMBOL(unregister_memory_isolate_notifier);
static void memory_block_release(struct device *dev)
{
struct memory_block *mem = to_memory_block(dev);
@ -175,11 +161,6 @@ int memory_notify(unsigned long val, void *v)
return blocking_notifier_call_chain(&memory_chain, val, v);
}
int memory_isolate_notify(unsigned long val, void *v)
{
return atomic_notifier_call_chain(&memory_isolate_chain, val, v);
}
/*
* The probe routines leave the pages uninitialized, just as the bootmem code
* does. Make sure we do not access them, but instead use only information from

View file

@ -55,19 +55,6 @@ struct memory_notify {
int status_change_nid;
};
/*
* During pageblock isolation, count the number of pages within the
* range [start_pfn, start_pfn + nr_pages) which are owned by code
* in the notifier chain.
*/
#define MEM_ISOLATE_COUNT (1<<0)
struct memory_isolate_notify {
unsigned long start_pfn; /* Start of range to check */
unsigned int nr_pages; /* # pages in range to check */
unsigned int pages_found; /* # pages owned found by callbacks */
};
struct notifier_block;
struct mem_section;
@ -94,27 +81,13 @@ static inline int memory_notify(unsigned long val, void *v)
{
return 0;
}
static inline int register_memory_isolate_notifier(struct notifier_block *nb)
{
return 0;
}
static inline void unregister_memory_isolate_notifier(struct notifier_block *nb)
{
}
static inline int memory_isolate_notify(unsigned long val, void *v)
{
return 0;
}
#else
extern int register_memory_notifier(struct notifier_block *nb);
extern void unregister_memory_notifier(struct notifier_block *nb);
extern int register_memory_isolate_notifier(struct notifier_block *nb);
extern void unregister_memory_isolate_notifier(struct notifier_block *nb);
int create_memory_block_devices(unsigned long start, unsigned long size);
void remove_memory_block_devices(unsigned long start, unsigned long size);
extern void memory_dev_init(void);
extern int memory_notify(unsigned long val, void *v);
extern int memory_isolate_notify(unsigned long val, void *v);
extern struct memory_block *find_memory_block(struct mem_section *);
typedef int (*walk_memory_blocks_func_t)(struct memory_block *, void *);
extern int walk_memory_blocks(unsigned long start, unsigned long size,

View file

@ -18,9 +18,7 @@
static int set_migratetype_isolate(struct page *page, int migratetype, int isol_flags)
{
struct zone *zone;
unsigned long flags, pfn;
struct memory_isolate_notify arg;
int notifier_ret;
unsigned long flags;
int ret = -EBUSY;
zone = page_zone(page);
@ -35,41 +33,11 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
if (is_migrate_isolate_page(page))
goto out;
pfn = page_to_pfn(page);
arg.start_pfn = pfn;
arg.nr_pages = pageblock_nr_pages;
arg.pages_found = 0;
/*
* It may be possible to isolate a pageblock even if the
* migratetype is not MIGRATE_MOVABLE. The memory isolation
* notifier chain is used by balloon drivers to return the
* number of pages in a range that are held by the balloon
* driver to shrink memory. If all the pages are accounted for
* by balloons, are free, or on the LRU, isolation can continue.
* Later, for example, when memory hotplug notifier runs, these
* pages reported as "can be isolated" should be isolated(freed)
* by the balloon driver through the memory notifier chain.
*/
notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
notifier_ret = notifier_to_errno(notifier_ret);
if (notifier_ret)
goto out;
/*
* FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
* We just check MOVABLE pages.
*/
if (!has_unmovable_pages(zone, page, arg.pages_found, migratetype,
isol_flags))
ret = 0;
/*
* immobile means "not-on-lru" pages. If immobile is larger than
* removable-by-driver pages reported by notifier, we'll fail.
*/
out:
if (!ret) {
if (!has_unmovable_pages(zone, page, 0, migratetype, isol_flags)) {
unsigned long nr_pages;
int mt = get_pageblock_migratetype(page);
@ -79,8 +47,10 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
NULL);
__mod_zone_freepage_state(zone, -nr_pages, mt);
ret = 0;
}
out:
spin_unlock_irqrestore(&zone->lock, flags);
if (!ret)
drain_all_pages(zone);