linux/arch/x86/kernel/cpu/intel_rdt.h
Vikas Shivappa de73f38f76 x86/intel_rdt/mba_sc: Feedback loop to dynamically update mem bandwidth
mba_sc is a feedback loop where we periodically read MBM counters and
try to restrict the bandwidth below a max value so the below is always
true:

  "current bandwidth(cur_bw) < user specified bandwidth(user_bw)"

The frequency of these checks is currently 1s and we just tag along the
MBM overflow timer to do the updates. Doing it once in a second also
makes the calculation of bandwidth easy. The steps of increase or
decrease of bandwidth is the minimum granularity specified by the
hardware.

Although the MBA's goal is to restrict the bandwidth below a maximum,
there may be a need to even increase the bandwidth. Since MBA controls
the L2 external bandwidth where as MBM measures the L3 external
bandwidth, we may end up restricting some rdtgroups unnecessarily. This
may happen in the sequence where rdtgroup (set of jobs) had high
"L3 <-> memory traffic" in initial phases -> mba_sc kicks in and reduced
bandwidth percentage values -> but after some it has mostly "L2 <-> L3"
traffic. In this scenario mba_sc increases the bandwidth percentage when
there is lesser memory traffic.

Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: vikas.shivappa@intel.com
Cc: ak@linux.intel.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/1524263781-14267-7-git-send-email-vikas.shivappa@linux.intel.com
2018-05-19 13:16:44 +02:00

472 lines
13 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_INTEL_RDT_H
#define _ASM_X86_INTEL_RDT_H
#include <linux/sched.h>
#include <linux/kernfs.h>
#include <linux/jump_label.h>
#define IA32_L3_QOS_CFG 0xc81
#define IA32_L2_QOS_CFG 0xc82
#define IA32_L3_CBM_BASE 0xc90
#define IA32_L2_CBM_BASE 0xd10
#define IA32_MBA_THRTL_BASE 0xd50
#define L3_QOS_CDP_ENABLE 0x01ULL
#define L2_QOS_CDP_ENABLE 0x01ULL
/*
* Event IDs are used to program IA32_QM_EVTSEL before reading event
* counter from IA32_QM_CTR
*/
#define QOS_L3_OCCUP_EVENT_ID 0x01
#define QOS_L3_MBM_TOTAL_EVENT_ID 0x02
#define QOS_L3_MBM_LOCAL_EVENT_ID 0x03
#define CQM_LIMBOCHECK_INTERVAL 1000
#define MBM_CNTR_WIDTH 24
#define MBM_OVERFLOW_INTERVAL 1000
#define MAX_MBA_BW 100u
#define RMID_VAL_ERROR BIT_ULL(63)
#define RMID_VAL_UNAVAIL BIT_ULL(62)
DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
/**
* struct mon_evt - Entry in the event list of a resource
* @evtid: event id
* @name: name of the event
*/
struct mon_evt {
u32 evtid;
char *name;
struct list_head list;
};
/**
* struct mon_data_bits - Monitoring details for each event file
* @rid: Resource id associated with the event file.
* @evtid: Event id associated with the event file
* @domid: The domain to which the event file belongs
*/
union mon_data_bits {
void *priv;
struct {
unsigned int rid : 10;
unsigned int evtid : 8;
unsigned int domid : 14;
} u;
};
struct rmid_read {
struct rdtgroup *rgrp;
struct rdt_domain *d;
int evtid;
bool first;
u64 val;
};
extern unsigned int intel_cqm_threshold;
extern bool rdt_alloc_capable;
extern bool rdt_mon_capable;
extern unsigned int rdt_mon_features;
enum rdt_group_type {
RDTCTRL_GROUP = 0,
RDTMON_GROUP,
RDT_NUM_GROUP,
};
/**
* struct mongroup - store mon group's data in resctrl fs.
* @mon_data_kn kernlfs node for the mon_data directory
* @parent: parent rdtgrp
* @crdtgrp_list: child rdtgroup node list
* @rmid: rmid for this rdtgroup
*/
struct mongroup {
struct kernfs_node *mon_data_kn;
struct rdtgroup *parent;
struct list_head crdtgrp_list;
u32 rmid;
};
/**
* 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
* @type: indicates type of this rdtgroup - either
* monitor only or ctrl_mon group
* @mon: mongroup related data
*/
struct rdtgroup {
struct kernfs_node *kn;
struct list_head rdtgroup_list;
u32 closid;
struct cpumask cpu_mask;
int flags;
atomic_t waitcount;
enum rdt_group_type type;
struct mongroup mon;
};
/* rdtgroup.flags */
#define RDT_DELETED 1
/* rftype.flags */
#define RFTYPE_FLAGS_CPUS_LIST 1
/*
* Define the file type flags for base and info directories.
*/
#define RFTYPE_INFO BIT(0)
#define RFTYPE_BASE BIT(1)
#define RF_CTRLSHIFT 4
#define RF_MONSHIFT 5
#define RF_TOPSHIFT 6
#define RFTYPE_CTRL BIT(RF_CTRLSHIFT)
#define RFTYPE_MON BIT(RF_MONSHIFT)
#define RFTYPE_TOP BIT(RF_TOPSHIFT)
#define RFTYPE_RES_CACHE BIT(8)
#define RFTYPE_RES_MB BIT(9)
#define RF_CTRL_INFO (RFTYPE_INFO | RFTYPE_CTRL)
#define RF_MON_INFO (RFTYPE_INFO | RFTYPE_MON)
#define RF_TOP_INFO (RFTYPE_INFO | RFTYPE_TOP)
#define RF_CTRL_BASE (RFTYPE_BASE | RFTYPE_CTRL)
/* List of all resource groups */
extern struct list_head rdt_all_groups;
extern int max_name_width, max_data_width;
int __init rdtgroup_init(void);
/**
* struct rftype - describe each file in the resctrl file system
* @name: File name
* @mode: Access mode
* @kf_ops: File operations
* @flags: File specific RFTYPE_FLAGS_* flags
* @fflags: File specific RF_* or RFTYPE_* flags
* @seq_show: Show content of the file
* @write: Write to the file
*/
struct rftype {
char *name;
umode_t mode;
struct kernfs_ops *kf_ops;
unsigned long flags;
unsigned long fflags;
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 mbm_state - status for each MBM counter in each domain
* @chunks: Total data moved (multiply by rdt_group.mon_scale to get bytes)
* @prev_msr Value of IA32_QM_CTR for this RMID last time we read it
* @chunks_bw Total local data moved. Used for bandwidth calculation
* @prev_bw_msr:Value of previous IA32_QM_CTR for bandwidth counting
* @prev_bw The most recent bandwidth in MBps
* @delta_bw Difference between the current and previous bandwidth
* @delta_comp Indicates whether to compute the delta_bw
*/
struct mbm_state {
u64 chunks;
u64 prev_msr;
u64 chunks_bw;
u64 prev_bw_msr;
u32 prev_bw;
u32 delta_bw;
bool delta_comp;
};
/**
* 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
* @rmid_busy_llc:
* bitmap of which limbo RMIDs are above threshold
* @mbm_total: saved state for MBM total bandwidth
* @mbm_local: saved state for MBM local bandwidth
* @mbm_over: worker to periodically read MBM h/w counters
* @cqm_limbo: worker to periodically read CQM h/w counters
* @mbm_work_cpu:
* worker cpu for MBM h/w counters
* @cqm_work_cpu:
* worker cpu for CQM h/w counters
* @ctrl_val: array of cache or mem ctrl values (indexed by CLOSID)
* @mbps_val: When mba_sc is enabled, this holds the bandwidth in MBps
* @new_ctrl: new ctrl value to be loaded
* @have_new_ctrl: did user provide new_ctrl for this domain
*/
struct rdt_domain {
struct list_head list;
int id;
struct cpumask cpu_mask;
unsigned long *rmid_busy_llc;
struct mbm_state *mbm_total;
struct mbm_state *mbm_local;
struct delayed_work mbm_over;
struct delayed_work cqm_limbo;
int mbm_work_cpu;
int cqm_work_cpu;
u32 *ctrl_val;
u32 *mbps_val;
u32 new_ctrl;
bool have_new_ctrl;
};
/**
* 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;
};
/**
* struct rdt_cache - Cache allocation related data
* @cbm_len: Length of the cache bit mask
* @min_cbm_bits: Minimum number of consecutive bits to be set
* @cbm_idx_mult: Multiplier of CBM index
* @cbm_idx_offset: Offset of CBM index. CBM index is computed by:
* closid * cbm_idx_multi + cbm_idx_offset
* in a cache bit mask
* @shareable_bits: Bitmask of shareable resource with other
* executing entities
*/
struct rdt_cache {
unsigned int cbm_len;
unsigned int min_cbm_bits;
unsigned int cbm_idx_mult;
unsigned int cbm_idx_offset;
unsigned int shareable_bits;
};
/**
* struct rdt_membw - Memory bandwidth allocation related data
* @max_delay: Max throttle delay. Delay is the hardware
* representation for memory bandwidth.
* @min_bw: Minimum memory bandwidth percentage user can request
* @bw_gran: Granularity at which the memory bandwidth is allocated
* @delay_linear: True if memory B/W delay is in linear scale
* @mba_sc: True if MBA software controller(mba_sc) is enabled
* @mb_map: Mapping of memory B/W percentage to memory B/W delay
*/
struct rdt_membw {
u32 max_delay;
u32 min_bw;
u32 bw_gran;
u32 delay_linear;
bool mba_sc;
u32 *mb_map;
};
static inline bool is_llc_occupancy_enabled(void)
{
return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
}
static inline bool is_mbm_total_enabled(void)
{
return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
}
static inline bool is_mbm_local_enabled(void)
{
return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
}
static inline bool is_mbm_enabled(void)
{
return (is_mbm_total_enabled() || is_mbm_local_enabled());
}
static inline bool is_mbm_event(int e)
{
return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
e <= QOS_L3_MBM_LOCAL_EVENT_ID);
}
/**
* struct rdt_resource - attributes of an RDT resource
* @rid: The index of the resource
* @alloc_enabled: Is allocation enabled on this machine
* @mon_enabled: Is monitoring enabled for this feature
* @alloc_capable: Is allocation available on this machine
* @mon_capable: Is monitor feature available on this machine
* @name: Name to use in "schemata" file
* @num_closid: Number of CLOSIDs available
* @cache_level: Which cache level defines scope of this resource
* @default_ctrl: Specifies default cache cbm or memory B/W percent.
* @msr_base: Base MSR address for CBMs
* @msr_update: Function pointer to update QOS MSRs
* @data_width: Character width of data when displaying
* @domains: All domains for this resource
* @cache: Cache allocation related data
* @format_str: Per resource format string to show domain value
* @parse_ctrlval: Per resource function pointer to parse control values
* @evt_list: List of monitoring events
* @num_rmid: Number of RMIDs available
* @mon_scale: cqm counter * mon_scale = occupancy in bytes
* @fflags: flags to choose base and info files
*/
struct rdt_resource {
int rid;
bool alloc_enabled;
bool mon_enabled;
bool alloc_capable;
bool mon_capable;
char *name;
int num_closid;
int cache_level;
u32 default_ctrl;
unsigned int msr_base;
void (*msr_update) (struct rdt_domain *d, struct msr_param *m,
struct rdt_resource *r);
int data_width;
struct list_head domains;
struct rdt_cache cache;
struct rdt_membw membw;
const char *format_str;
int (*parse_ctrlval) (char *buf, struct rdt_resource *r,
struct rdt_domain *d);
struct list_head evt_list;
int num_rmid;
unsigned int mon_scale;
unsigned long fflags;
};
int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d);
int parse_bw(char *buf, struct rdt_resource *r, struct rdt_domain *d);
extern struct mutex rdtgroup_mutex;
extern struct rdt_resource rdt_resources_all[];
extern struct rdtgroup rdtgroup_default;
DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
int __init rdtgroup_init(void);
enum {
RDT_RESOURCE_L3,
RDT_RESOURCE_L3DATA,
RDT_RESOURCE_L3CODE,
RDT_RESOURCE_L2,
RDT_RESOURCE_L2DATA,
RDT_RESOURCE_L2CODE,
RDT_RESOURCE_MBA,
/* 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->alloc_capable || r->mon_capable)
#define for_each_alloc_capable_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->alloc_capable)
#define for_each_mon_capable_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->mon_capable)
#define for_each_alloc_enabled_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->alloc_enabled)
#define for_each_mon_enabled_rdt_resource(r) \
for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
r++) \
if (r->mon_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=3).EAX */
union cpuid_0x10_3_eax {
struct {
unsigned int max_delay:12;
} split;
unsigned int full;
};
/* CPUID.(EAX=10H, ECX=ResID).EDX */
union cpuid_0x10_x_edx {
struct {
unsigned int cos_max:16;
} split;
unsigned int full;
};
void rdt_last_cmd_clear(void);
void rdt_last_cmd_puts(const char *s);
void rdt_last_cmd_printf(const char *fmt, ...);
void rdt_ctrl_update(void *arg);
struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
void rdtgroup_kn_unlock(struct kernfs_node *kn);
struct rdt_domain *rdt_find_domain(struct rdt_resource *r, int id,
struct list_head **pos);
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);
struct rdt_domain *get_domain_from_cpu(int cpu, struct rdt_resource *r);
int alloc_rmid(void);
void free_rmid(u32 rmid);
int rdt_get_mon_l3_config(struct rdt_resource *r);
void mon_event_count(void *info);
int rdtgroup_mondata_show(struct seq_file *m, void *arg);
void rmdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
unsigned int dom_id);
void mkdir_mondata_subdir_allrdtgrp(struct rdt_resource *r,
struct rdt_domain *d);
void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
struct rdtgroup *rdtgrp, int evtid, int first);
void mbm_setup_overflow_handler(struct rdt_domain *dom,
unsigned long delay_ms);
void mbm_handle_overflow(struct work_struct *work);
bool is_mba_sc(struct rdt_resource *r);
void setup_default_ctrlval(struct rdt_resource *r, u32 *dc, u32 *dm);
u32 delay_bw_map(unsigned long bw, struct rdt_resource *r);
void cqm_setup_limbo_handler(struct rdt_domain *dom, unsigned long delay_ms);
void cqm_handle_limbo(struct work_struct *work);
bool has_busy_rmid(struct rdt_resource *r, struct rdt_domain *d);
void __check_limbo(struct rdt_domain *d, bool force_free);
#endif /* _ASM_X86_INTEL_RDT_H */