linux-stable/include/linux/node.h
Dave Jiang 6a954e94d0 base/node / acpi: Change 'node_hmem_attrs' to 'access_coordinates'
Dan Williams suggested changing the struct 'node_hmem_attrs' to
'access_coordinates' [1]. The struct is a container of r/w-latency and
r/w-bandwidth numbers. Moving forward, this container will also be used by
CXL to store the performance characteristics of each link hop in
the PCIE/CXL topology. So, where node_hmem_attrs is just the access
parameters of a memory-node, access_coordinates applies more broadly
to hardware topology characteristics. The observation is that seemed like
an exercise in having the application identify "where" it falls on a
spectrum of bandwidth and latency needs. For the tuple of
read/write-latency and read/write-bandwidth, "coordinates" is not a perfect
fit. Sometimes it is just conveying values in isolation and not a
"location" relative to other performance points, but in the end this data
is used to identify the performance operation point of a given memory-node.
[2]

Link: http://lore.kernel.org/r/64471313421f7_1b66294d5@dwillia2-xfh.jf.intel.com.notmuch/
Link: https://lore.kernel.org/linux-cxl/645e6215ee0de_1e6f2945e@dwillia2-xfh.jf.intel.com.notmuch/
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/170319615734.2212653.15319394025985499185.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-12-22 14:23:13 -08:00

172 lines
4.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/node.h - generic node definition
*
* This is mainly for topological representation. We define the
* basic 'struct node' here, which can be embedded in per-arch
* definitions of processors.
*
* Basic handling of the devices is done in drivers/base/node.c
* and system devices are handled in drivers/base/sys.c.
*
* Nodes are exported via driverfs in the class/node/devices/
* directory.
*/
#ifndef _LINUX_NODE_H_
#define _LINUX_NODE_H_
#include <linux/device.h>
#include <linux/cpumask.h>
#include <linux/list.h>
/**
* struct access_coordinate - generic performance coordinates container
*
* @read_bandwidth: Read bandwidth in MB/s
* @write_bandwidth: Write bandwidth in MB/s
* @read_latency: Read latency in nanoseconds
* @write_latency: Write latency in nanoseconds
*/
struct access_coordinate {
unsigned int read_bandwidth;
unsigned int write_bandwidth;
unsigned int read_latency;
unsigned int write_latency;
};
enum cache_indexing {
NODE_CACHE_DIRECT_MAP,
NODE_CACHE_INDEXED,
NODE_CACHE_OTHER,
};
enum cache_write_policy {
NODE_CACHE_WRITE_BACK,
NODE_CACHE_WRITE_THROUGH,
NODE_CACHE_WRITE_OTHER,
};
/**
* struct node_cache_attrs - system memory caching attributes
*
* @indexing: The ways memory blocks may be placed in cache
* @write_policy: Write back or write through policy
* @size: Total size of cache in bytes
* @line_size: Number of bytes fetched on a cache miss
* @level: The cache hierarchy level
*/
struct node_cache_attrs {
enum cache_indexing indexing;
enum cache_write_policy write_policy;
u64 size;
u16 line_size;
u8 level;
};
#ifdef CONFIG_HMEM_REPORTING
void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
unsigned access);
#else
static inline void node_add_cache(unsigned int nid,
struct node_cache_attrs *cache_attrs)
{
}
static inline void node_set_perf_attrs(unsigned int nid,
struct access_coordinate *coord,
unsigned access)
{
}
#endif
struct node {
struct device dev;
struct list_head access_list;
#ifdef CONFIG_HMEM_REPORTING
struct list_head cache_attrs;
struct device *cache_dev;
#endif
};
struct memory_block;
extern struct node *node_devices[];
#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA)
void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
unsigned long end_pfn,
enum meminit_context context);
#else
static inline void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
unsigned long end_pfn,
enum meminit_context context)
{
}
#endif
extern void unregister_node(struct node *node);
#ifdef CONFIG_NUMA
extern void node_dev_init(void);
/* Core of the node registration - only memory hotplug should use this */
extern int __register_one_node(int nid);
/* Registers an online node */
static inline int register_one_node(int nid)
{
int error = 0;
if (node_online(nid)) {
struct pglist_data *pgdat = NODE_DATA(nid);
unsigned long start_pfn = pgdat->node_start_pfn;
unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
error = __register_one_node(nid);
if (error)
return error;
register_memory_blocks_under_node(nid, start_pfn, end_pfn,
MEMINIT_EARLY);
}
return error;
}
extern void unregister_one_node(int nid);
extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
extern int register_memory_node_under_compute_node(unsigned int mem_nid,
unsigned int cpu_nid,
unsigned access);
#else
static inline void node_dev_init(void)
{
}
static inline int __register_one_node(int nid)
{
return 0;
}
static inline int register_one_node(int nid)
{
return 0;
}
static inline int unregister_one_node(int nid)
{
return 0;
}
static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
{
return 0;
}
static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
{
return 0;
}
static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
{
}
#endif
#define to_node(device) container_of(device, struct node, dev)
#endif /* _LINUX_NODE_H_ */