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#ifndef _ASM_X86_INTEL_RDT_H
#define _ASM_X86_INTEL_RDT_H
#ifdef CONFIG_INTEL_RDT_A
#include <linux/sched.h>
#include <linux/kernfs.h>
#include <linux/jump_label.h>
#include <asm/intel_rdt_common.h>
#define IA32_L3_QOS_CFG 0xc81
#define IA32_L3_CBM_BASE 0xc90
#define IA32_L2_CBM_BASE 0xd10
#define L3_QOS_CDP_ENABLE 0x01ULL
/**
* struct rdtgroup - store rdtgroup's data in resctrl file system.
* @kn: kernfs node
* @rdtgroup_list: linked list for all rdtgroups
* @closid: closid for this rdtgroup
* @cpu_mask: CPUs assigned to this rdtgroup
* @flags: status bits
* @waitcount: how many cpus expect to find this
* group when they acquire rdtgroup_mutex
*/
struct rdtgroup {
struct kernfs_node *kn;
struct list_head rdtgroup_list;
int closid;
struct cpumask cpu_mask;
int flags;
atomic_t waitcount;
};
/* rdtgroup.flags */
#define RDT_DELETED 1
/* List of all resource groups */
extern struct list_head rdt_all_groups;
int __init rdtgroup_init(void);
/**
* struct rftype - describe each file in the resctrl file system
* @name: file name
* @mode: access mode
* @kf_ops: operations
* @seq_show: show content of the file
* @write: write to the file
*/
struct rftype {
char *name;
umode_t mode;
struct kernfs_ops *kf_ops;
int (*seq_show)(struct kernfs_open_file *of,
struct seq_file *sf, void *v);
/*
* write() is the generic write callback which maps directly to
* kernfs write operation and overrides all other operations.
* Maximum write size is determined by ->max_write_len.
*/
ssize_t (*write)(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off);
};
/**
* struct rdt_resource - attributes of an RDT resource
* @enabled: Is this feature enabled on this machine
* @capable: Is this feature available on this machine
* @name: Name to use in "schemata" file
* @num_closid: Number of CLOSIDs available
* @max_cbm: Largest Cache Bit Mask allowed
* @min_cbm_bits: Minimum number of consecutive bits to be set
* in a cache bit mask
* @domains: All domains for this resource
* @msr_base: Base MSR address for CBMs
* @cache_level: Which cache level defines scope of this domain
* @cbm_idx_multi: Multiplier of CBM index
* @cbm_idx_offset: Offset of CBM index. CBM index is computed by:
* closid * cbm_idx_multi + cbm_idx_offset
*/
struct rdt_resource {
bool enabled;
bool capable;
char *name;
int num_closid;
int cbm_len;
int min_cbm_bits;
u32 max_cbm;
struct list_head domains;
int msr_base;
int cache_level;
int cbm_idx_multi;
int cbm_idx_offset;
};
/**
* struct rdt_domain - group of cpus sharing an RDT resource
* @list: all instances of this resource
* @id: unique id for this instance
* @cpu_mask: which cpus share this resource
* @cbm: array of cache bit masks (indexed by CLOSID)
* @new_cbm: new cbm value to be loaded
* @have_new_cbm: did user provide new_cbm for this domain
*/
struct rdt_domain {
struct list_head list;
int id;
struct cpumask cpu_mask;
u32 *cbm;
u32 new_cbm;
bool have_new_cbm;
};
/**
* struct msr_param - set a range of MSRs from a domain
* @res: The resource to use
* @low: Beginning index from base MSR
* @high: End index
*/
struct msr_param {
struct rdt_resource *res;
int low;
int high;
};
extern struct mutex rdtgroup_mutex;
extern struct rdt_resource rdt_resources_all[];
extern struct rdtgroup rdtgroup_default;
DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
int __init rdtgroup_init(void);
enum {
RDT_RESOURCE_L3,
RDT_RESOURCE_L3DATA,
RDT_RESOURCE_L3CODE,
RDT_RESOURCE_L2,
/* Must be the last */
RDT_NUM_RESOURCES,
};
#define for_each_capable_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->capable)
#define for_each_enabled_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->enabled)
/* CPUID.(EAX=10H, ECX=ResID=1).EAX */
union cpuid_0x10_1_eax {
struct {
unsigned int cbm_len:5;
} split;
unsigned int full;
};
/* CPUID.(EAX=10H, ECX=ResID=1).EDX */
union cpuid_0x10_1_edx {
struct {
unsigned int cos_max:16;
} split;
unsigned int full;
};
DECLARE_PER_CPU_READ_MOSTLY(int, cpu_closid);
void rdt_cbm_update(void *arg);
struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
void rdtgroup_kn_unlock(struct kernfs_node *kn);
ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off);
int rdtgroup_schemata_show(struct kernfs_open_file *of,
struct seq_file *s, void *v);
/*
* intel_rdt_sched_in() - Writes the task's CLOSid to IA32_PQR_MSR
*
* Following considerations are made so that this has minimal impact
* on scheduler hot path:
* - This will stay as no-op unless we are running on an Intel SKU
* which supports resource control and we enable by mounting the
* resctrl file system.
* - Caches the per cpu CLOSid values and does the MSR write only
* when a task with a different CLOSid is scheduled in.
*
* Must be called with preemption disabled.
*/
static inline void intel_rdt_sched_in(void)
{
if (static_branch_likely(&rdt_enable_key)) {
struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
int closid;
/*
* If this task has a closid assigned, use it.
* Else use the closid assigned to this cpu.
*/
closid = current->closid;
if (closid == 0)
closid = this_cpu_read(cpu_closid);
if (closid != state->closid) {
state->closid = closid;
wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, closid);
}
}
}
#else
static inline void intel_rdt_sched_in(void) {}
#endif /* CONFIG_INTEL_RDT_A */
#endif /* _ASM_X86_INTEL_RDT_H */
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