linux-stable/include/linux/memory.h
Yasunori Goto b9049e2344 memory hotplug: make kmem_cache_node for SLUB on memory online avoid panic
Fix a panic due to access NULL pointer of kmem_cache_node at discard_slab()
after memory online.

When memory online is called, kmem_cache_nodes are created for all SLUBs
for new node whose memory are available.

slab_mem_going_online_callback() is called to make kmem_cache_node() in
callback of memory online event.  If it (or other callbacks) fails, then
slab_mem_offline_callback() is called for rollback.

In memory offline, slab_mem_going_offline_callback() is called to shrink
all slub cache, then slab_mem_offline_callback() is called later.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: locking fix]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-22 08:13:17 -07:00

96 lines
2.7 KiB
C

/*
* include/linux/memory.h - generic memory definition
*
* This is mainly for topological representation. We define the
* basic "struct memory_block" here, which can be embedded in per-arch
* definitions or NUMA information.
*
* Basic handling of the devices is done in drivers/base/memory.c
* and system devices are handled in drivers/base/sys.c.
*
* Memory block are exported via sysfs in the class/memory/devices/
* directory.
*
*/
#ifndef _LINUX_MEMORY_H_
#define _LINUX_MEMORY_H_
#include <linux/sysdev.h>
#include <linux/node.h>
#include <linux/compiler.h>
#include <asm/semaphore.h>
struct memory_block {
unsigned long phys_index;
unsigned long state;
/*
* This serializes all state change requests. It isn't
* held during creation because the control files are
* created long after the critical areas during
* initialization.
*/
struct semaphore state_sem;
int phys_device; /* to which fru does this belong? */
void *hw; /* optional pointer to fw/hw data */
int (*phys_callback)(struct memory_block *);
struct sys_device sysdev;
};
/* These states are exposed to userspace as text strings in sysfs */
#define MEM_ONLINE (1<<0) /* exposed to userspace */
#define MEM_GOING_OFFLINE (1<<1) /* exposed to userspace */
#define MEM_OFFLINE (1<<2) /* exposed to userspace */
#define MEM_GOING_ONLINE (1<<3)
#define MEM_CANCEL_ONLINE (1<<4)
#define MEM_CANCEL_OFFLINE (1<<5)
struct memory_notify {
unsigned long start_pfn;
unsigned long nr_pages;
int status_change_nid;
};
struct notifier_block;
struct mem_section;
#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
static inline int memory_dev_init(void)
{
return 0;
}
static inline int register_memory_notifier(struct notifier_block *nb)
{
return 0;
}
static inline void unregister_memory_notifier(struct notifier_block *nb)
{
}
static inline int memory_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_new_memory(struct mem_section *);
extern int unregister_memory_section(struct mem_section *);
extern int memory_dev_init(void);
extern int remove_memory_block(unsigned long, struct mem_section *, int);
extern int memory_notify(unsigned long val, void *v);
#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
#ifdef CONFIG_MEMORY_HOTPLUG
#define hotplug_memory_notifier(fn, pri) { \
static struct notifier_block fn##_mem_nb = \
{ .notifier_call = fn, .priority = pri }; \
register_memory_notifier(&fn##_mem_nb); \
}
#else
#define hotplug_memory_notifier(fn, pri) do { } while (0)
#endif
#endif /* _LINUX_MEMORY_H_ */