68c3a6ac65
Patch series "mm: drop superfluous section checks when onlining/offlining". Let's drop some superfluous section checks on the onlining/offlining path. This patch (of 3): Since commitc5e79ef561("mm/memory_hotplug.c: don't allow to online/offline memory blocks with holes") we have a generic check in offline_pages() that disallows offlining memory blocks with holes. Memory blocks with missing sections are just another variant of these type of blocks. We can stop checking (and especially storing) present sections. A proper error message is now printed why offlining failed. section_count was initially introduced in commit0768121597("Driver core: Add section count to memory_block struct") in order to detect when it is okay to remove a memory block. It was used in commit26bbe7ef6d("drivers/base/memory.c: prohibit offlining of memory blocks with missing sections") to disallow offlining memory blocks with missing sections. As we refactored creation/removal of memory devices and have a proper check for holes in place, we can drop the section_count. This also removes a leftover comment regarding the mem_sysfs_mutex, which was removed in commit848e19ad3c("drivers/base/memory.c: drop the mem_sysfs_mutex"). Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Link: http://lkml.kernel.org/r/20200127110424.5757-2-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
118 lines
3.7 KiB
C
118 lines
3.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* 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/node.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/notifier.h>
|
|
|
|
#define MIN_MEMORY_BLOCK_SIZE (1UL << SECTION_SIZE_BITS)
|
|
|
|
struct memory_block {
|
|
unsigned long start_section_nr;
|
|
unsigned long state; /* serialized by the dev->lock */
|
|
int online_type; /* for passing data to online routine */
|
|
int phys_device; /* to which fru does this belong? */
|
|
struct device dev;
|
|
int nid; /* NID for this memory block */
|
|
};
|
|
|
|
int arch_get_memory_phys_device(unsigned long start_pfn);
|
|
unsigned long memory_block_size_bytes(void);
|
|
int set_memory_block_size_order(unsigned int order);
|
|
|
|
/* 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_normal;
|
|
int status_change_nid_high;
|
|
int status_change_nid;
|
|
};
|
|
|
|
struct notifier_block;
|
|
struct mem_section;
|
|
|
|
/*
|
|
* Priorities for the hotplug memory callback routines (stored in decreasing
|
|
* order in the callback chain)
|
|
*/
|
|
#define SLAB_CALLBACK_PRI 1
|
|
#define IPC_CALLBACK_PRI 10
|
|
|
|
#ifndef CONFIG_MEMORY_HOTPLUG_SPARSE
|
|
static inline void memory_dev_init(void)
|
|
{
|
|
return;
|
|
}
|
|
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);
|
|
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 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,
|
|
void *arg, walk_memory_blocks_func_t func);
|
|
extern int for_each_memory_block(void *arg, walk_memory_blocks_func_t func);
|
|
#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 __meminitdata struct notifier_block fn##_mem_nb =\
|
|
{ .notifier_call = fn, .priority = pri };\
|
|
register_memory_notifier(&fn##_mem_nb); \
|
|
})
|
|
#define register_hotmemory_notifier(nb) register_memory_notifier(nb)
|
|
#define unregister_hotmemory_notifier(nb) unregister_memory_notifier(nb)
|
|
#else
|
|
#define hotplug_memory_notifier(fn, pri) ({ 0; })
|
|
/* These aren't inline functions due to a GCC bug. */
|
|
#define register_hotmemory_notifier(nb) ({ (void)(nb); 0; })
|
|
#define unregister_hotmemory_notifier(nb) ({ (void)(nb); })
|
|
#endif
|
|
|
|
/*
|
|
* Kernel text modification mutex, used for code patching. Users of this lock
|
|
* can sleep.
|
|
*/
|
|
extern struct mutex text_mutex;
|
|
|
|
#endif /* _LINUX_MEMORY_H_ */
|