mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-13 16:47:05 +07:00
c04fc586c1
Show node to memory section relationship with symlinks in sysfs
Add /sys/devices/system/node/nodeX/memoryY symlinks for all
the memory sections located on nodeX. For example:
/sys/devices/system/node/node1/memory135 -> ../../memory/memory135
indicates that memory section 135 resides on node1.
Also revises documentation to cover this change as well as updating
Documentation/ABI/testing/sysfs-devices-memory to include descriptions
of memory hotremove files 'phys_device', 'phys_index', and 'state'
that were previously not described there.
In addition to it always being a good policy to provide users with
the maximum possible amount of physical location information for
resources that can be hot-added and/or hot-removed, the following
are some (but likely not all) of the user benefits provided by
this change.
Immediate:
- Provides information needed to determine the specific node
on which a defective DIMM is located. This will reduce system
downtime when the node or defective DIMM is swapped out.
- Prevents unintended onlining of a memory section that was
previously offlined due to a defective DIMM. This could happen
during node hot-add when the user or node hot-add assist script
onlines _all_ offlined sections due to user or script inability
to identify the specific memory sections located on the hot-added
node. The consequences of reintroducing the defective memory
could be ugly.
- Provides information needed to vary the amount and distribution
of memory on specific nodes for testing or debugging purposes.
Future:
- Will provide information needed to identify the memory
sections that need to be offlined prior to physical removal
of a specific node.
Symlink creation during boot was tested on 2-node x86_64, 2-node
ppc64, and 2-node ia64 systems. Symlink creation during physical
memory hot-add tested on a 2-node x86_64 system.
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
103 lines
3.0 KiB
C
103 lines
3.0 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 <linux/mutex.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 mutex state_mutex;
|
|
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;
|
|
|
|
/*
|
|
* 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 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(int, 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);
|
|
extern struct memory_block *find_memory_block(struct mem_section *);
|
|
#define CONFIG_MEM_BLOCK_SIZE (PAGES_PER_SECTION<<PAGE_SHIFT)
|
|
enum mem_add_context { BOOT, HOTPLUG };
|
|
#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); \
|
|
}
|
|
#else
|
|
#define hotplug_memory_notifier(fn, pri) do { } while (0)
|
|
#endif
|
|
|
|
#endif /* _LINUX_MEMORY_H_ */
|