mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-24 21:30:53 +07:00
246246cbde
This patch adds initial support for providing processor cache information to userspace through sysfs interface. This is based on already existing implementations(x86, ia64, s390 and powerpc) and hence the interface is intended to be fully compatible. The main purpose of this generic support is to avoid further code duplication to support new architectures and also to unify all the existing different implementations. This implementation maintains the hierarchy of cache objects which reflects the system's cache topology. Cache devices are instantiated as needed as CPUs come online. The cache information is replicated per-cpu even if they are shared. A per-cpu array of cache information maintained is used mainly for sysfs-related book keeping. It also implements the shared_cpu_map attribute, which is essential for enabling both kernel and user-space to discover the system's overall cache topology. This patch also add the missing ABI documentation for the cacheinfo sysfs interface already, which is well defined and widely used. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-api@vger.kernel.org Cc: linux390@de.ibm.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: x86@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
101 lines
3.0 KiB
C
101 lines
3.0 KiB
C
#ifndef _LINUX_CACHEINFO_H
|
|
#define _LINUX_CACHEINFO_H
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/smp.h>
|
|
|
|
struct device_node;
|
|
struct attribute;
|
|
|
|
enum cache_type {
|
|
CACHE_TYPE_NOCACHE = 0,
|
|
CACHE_TYPE_INST = BIT(0),
|
|
CACHE_TYPE_DATA = BIT(1),
|
|
CACHE_TYPE_SEPARATE = CACHE_TYPE_INST | CACHE_TYPE_DATA,
|
|
CACHE_TYPE_UNIFIED = BIT(2),
|
|
};
|
|
|
|
/**
|
|
* struct cacheinfo - represent a cache leaf node
|
|
* @type: type of the cache - data, inst or unified
|
|
* @level: represents the hierarcy in the multi-level cache
|
|
* @coherency_line_size: size of each cache line usually representing
|
|
* the minimum amount of data that gets transferred from memory
|
|
* @number_of_sets: total number of sets, a set is a collection of cache
|
|
* lines sharing the same index
|
|
* @ways_of_associativity: number of ways in which a particular memory
|
|
* block can be placed in the cache
|
|
* @physical_line_partition: number of physical cache lines sharing the
|
|
* same cachetag
|
|
* @size: Total size of the cache
|
|
* @shared_cpu_map: logical cpumask representing all the cpus sharing
|
|
* this cache node
|
|
* @attributes: bitfield representing various cache attributes
|
|
* @of_node: if devicetree is used, this represents either the cpu node in
|
|
* case there's no explicit cache node or the cache node itself in the
|
|
* device tree
|
|
* @disable_sysfs: indicates whether this node is visible to the user via
|
|
* sysfs or not
|
|
* @priv: pointer to any private data structure specific to particular
|
|
* cache design
|
|
*
|
|
* While @of_node, @disable_sysfs and @priv are used for internal book
|
|
* keeping, the remaining members form the core properties of the cache
|
|
*/
|
|
struct cacheinfo {
|
|
enum cache_type type;
|
|
unsigned int level;
|
|
unsigned int coherency_line_size;
|
|
unsigned int number_of_sets;
|
|
unsigned int ways_of_associativity;
|
|
unsigned int physical_line_partition;
|
|
unsigned int size;
|
|
cpumask_t shared_cpu_map;
|
|
unsigned int attributes;
|
|
#define CACHE_WRITE_THROUGH BIT(0)
|
|
#define CACHE_WRITE_BACK BIT(1)
|
|
#define CACHE_WRITE_POLICY_MASK \
|
|
(CACHE_WRITE_THROUGH | CACHE_WRITE_BACK)
|
|
#define CACHE_READ_ALLOCATE BIT(2)
|
|
#define CACHE_WRITE_ALLOCATE BIT(3)
|
|
#define CACHE_ALLOCATE_POLICY_MASK \
|
|
(CACHE_READ_ALLOCATE | CACHE_WRITE_ALLOCATE)
|
|
|
|
struct device_node *of_node;
|
|
bool disable_sysfs;
|
|
void *priv;
|
|
};
|
|
|
|
struct cpu_cacheinfo {
|
|
struct cacheinfo *info_list;
|
|
unsigned int num_levels;
|
|
unsigned int num_leaves;
|
|
};
|
|
|
|
/*
|
|
* Helpers to make sure "func" is executed on the cpu whose cache
|
|
* attributes are being detected
|
|
*/
|
|
#define DEFINE_SMP_CALL_CACHE_FUNCTION(func) \
|
|
static inline void _##func(void *ret) \
|
|
{ \
|
|
int cpu = smp_processor_id(); \
|
|
*(int *)ret = __##func(cpu); \
|
|
} \
|
|
\
|
|
int func(unsigned int cpu) \
|
|
{ \
|
|
int ret; \
|
|
smp_call_function_single(cpu, _##func, &ret, true); \
|
|
return ret; \
|
|
}
|
|
|
|
struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
|
|
int init_cache_level(unsigned int cpu);
|
|
int populate_cache_leaves(unsigned int cpu);
|
|
|
|
const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
|
|
|
|
#endif /* _LINUX_CACHEINFO_H */
|