arch/x86/include/asm/intel_rdt.h

   1 #ifndef _ASM_X86_INTEL_RDT_H
   2 #define _ASM_X86_INTEL_RDT_H
   3
   4 #ifdef CONFIG_INTEL_RDT_A
   5
   6 #include <linux/sched.h>
   7 #include <linux/kernfs.h>
   8 #include <linux/jump_label.h>
   9
  10 #include <asm/intel_rdt_common.h>
  11
  12 #define IA32_L3_QOS_CFG         0xc81
  13 #define IA32_L3_CBM_BASE        0xc90
  14 #define IA32_L2_CBM_BASE        0xd10
  15
  16 #define L3_QOS_CDP_ENABLE       0x01ULL
  17
  18 /**
  19  * struct rdtgroup - store rdtgroup's data in resctrl file system.
  20  * @kn:                         kernfs node
  21  * @rdtgroup_list:              linked list for all rdtgroups
  22  * @closid:                     closid for this rdtgroup
  23  * @cpu_mask:                   CPUs assigned to this rdtgroup
  24  * @flags:                      status bits
  25  * @waitcount:                  how many cpus expect to find this
  26  *                              group when they acquire rdtgroup_mutex
  27  */
  28 struct rdtgroup {
  29         struct kernfs_node      *kn;
  30         struct list_head        rdtgroup_list;
  31         int                     closid;
  32         struct cpumask          cpu_mask;
  33         int                     flags;
  34         atomic_t                waitcount;
  35 };
  36
  37 /* rdtgroup.flags */
  38 #define RDT_DELETED             1
  39
  40 /* List of all resource groups */
  41 extern struct list_head rdt_all_groups;
  42
  43 int __init rdtgroup_init(void);
  44
  45 /**
  46  * struct rftype - describe each file in the resctrl file system
  47  * @name: file name
  48  * @mode: access mode
  49  * @kf_ops: operations
  50  * @seq_show: show content of the file
  51  * @write: write to the file
  52  */
  53 struct rftype {
  54         char                    *name;
  55         umode_t                 mode;
  56         struct kernfs_ops       *kf_ops;
  57
  58         int (*seq_show)(struct kernfs_open_file *of,
  59                         struct seq_file *sf, void *v);
  60         /*
  61          * write() is the generic write callback which maps directly to
  62          * kernfs write operation and overrides all other operations.
  63          * Maximum write size is determined by ->max_write_len.
  64          */
  65         ssize_t (*write)(struct kernfs_open_file *of,
  66                          char *buf, size_t nbytes, loff_t off);
  67 };
  68
  69 /**
  70  * struct rdt_resource - attributes of an RDT resource
  71  * @enabled:                    Is this feature enabled on this machine
  72  * @capable:                    Is this feature available on this machine
  73  * @name:                       Name to use in "schemata" file
  74  * @num_closid:                 Number of CLOSIDs available
  75  * @max_cbm:                    Largest Cache Bit Mask allowed
  76  * @min_cbm_bits:               Minimum number of consecutive bits to be set
  77  *                              in a cache bit mask
  78  * @domains:                    All domains for this resource
  79  * @num_domains:                Number of domains active
  80  * @msr_base:                   Base MSR address for CBMs
  81  * @tmp_cbms:                   Scratch space when updating schemata
  82  * @num_tmp_cbms:               Number of CBMs in tmp_cbms
  83  * @cache_level:                Which cache level defines scope of this domain
  84  * @cbm_idx_multi:              Multiplier of CBM index
  85  * @cbm_idx_offset:             Offset of CBM index. CBM index is computed by:
  86  *                              closid * cbm_idx_multi + cbm_idx_offset
  87  */
  88 struct rdt_resource {
  89         bool                    enabled;
  90         bool                    capable;
  91         char                    *name;
  92         int                     num_closid;
  93         int                     cbm_len;
  94         int                     min_cbm_bits;
  95         u32                     max_cbm;
  96         struct list_head        domains;
  97         int                     num_domains;
  98         int                     msr_base;
  99         u32                     *tmp_cbms;
 100         int                     num_tmp_cbms;
 101         int                     cache_level;
 102         int                     cbm_idx_multi;
 103         int                     cbm_idx_offset;
 104 };
 105
 106 /**
 107  * struct rdt_domain - group of cpus sharing an RDT resource
 108  * @list:       all instances of this resource
 109  * @id:         unique id for this instance
 110  * @cpu_mask:   which cpus share this resource
 111  * @cbm:        array of cache bit masks (indexed by CLOSID)
 112  */
 113 struct rdt_domain {
 114         struct list_head        list;
 115         int                     id;
 116         struct cpumask          cpu_mask;
 117         u32                     *cbm;
 118 };
 119
 120 /**
 121  * struct msr_param - set a range of MSRs from a domain
 122  * @res:       The resource to use
 123  * @low:       Beginning index from base MSR
 124  * @high:      End index
 125  */
 126 struct msr_param {
 127         struct rdt_resource     *res;
 128         int                     low;
 129         int                     high;
 130 };
 131
 132 extern struct mutex rdtgroup_mutex;
 133
 134 extern struct rdt_resource rdt_resources_all[];
 135 extern struct rdtgroup rdtgroup_default;
 136 DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
 137
 138 int __init rdtgroup_init(void);
 139
 140 enum {
 141         RDT_RESOURCE_L3,
 142         RDT_RESOURCE_L3DATA,
 143         RDT_RESOURCE_L3CODE,
 144         RDT_RESOURCE_L2,
 145
 146         /* Must be the last */
 147         RDT_NUM_RESOURCES,
 148 };
 149
 150 #define for_each_capable_rdt_resource(r)                                      \
 151         for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
 152              r++)                                                             \
 153                 if (r->capable)
 154
 155 #define for_each_enabled_rdt_resource(r)                                      \
 156         for (r = rdt_resources_all; r < rdt_resources_all + RDT_NUM_RESOURCES;\
 157              r++)                                                             \
 158                 if (r->enabled)
 159
 160 /* CPUID.(EAX=10H, ECX=ResID=1).EAX */
 161 union cpuid_0x10_1_eax {
 162         struct {
 163                 unsigned int cbm_len:5;
 164         } split;
 165         unsigned int full;
 166 };
 167
 168 /* CPUID.(EAX=10H, ECX=ResID=1).EDX */
 169 union cpuid_0x10_1_edx {
 170         struct {
 171                 unsigned int cos_max:16;
 172         } split;
 173         unsigned int full;
 174 };
 175
 176 DECLARE_PER_CPU_READ_MOSTLY(int, cpu_closid);
 177
 178 void rdt_cbm_update(void *arg);
 179 struct rdtgroup *rdtgroup_kn_lock_live(struct kernfs_node *kn);
 180 void rdtgroup_kn_unlock(struct kernfs_node *kn);
 181 ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
 182                                 char *buf, size_t nbytes, loff_t off);
 183 int rdtgroup_schemata_show(struct kernfs_open_file *of,
 184                            struct seq_file *s, void *v);
 185
 186 /*
 187  * intel_rdt_sched_in() - Writes the task's CLOSid to IA32_PQR_MSR
 188  *
 189  * Following considerations are made so that this has minimal impact
 190  * on scheduler hot path:
 191  * - This will stay as no-op unless we are running on an Intel SKU
 192  *   which supports resource control and we enable by mounting the
 193  *   resctrl file system.
 194  * - Caches the per cpu CLOSid values and does the MSR write only
 195  *   when a task with a different CLOSid is scheduled in.
 196  *
 197  * Must be called with preemption disabled.
 198  */
 199 static inline void intel_rdt_sched_in(void)
 200 {
 201         if (static_branch_likely(&rdt_enable_key)) {
 202                 struct intel_pqr_state *state = this_cpu_ptr(&pqr_state);
 203                 int closid;
 204
 205                 /*
 206                  * If this task has a closid assigned, use it.
 207                  * Else use the closid assigned to this cpu.
 208                  */
 209                 closid = current->closid;
 210                 if (closid == 0)
 211                         closid = this_cpu_read(cpu_closid);
 212
 213                 if (closid != state->closid) {
 214                         state->closid = closid;
 215                         wrmsr(MSR_IA32_PQR_ASSOC, state->rmid, closid);
 216                 }
 217         }
 218 }
 219
 220 #else
 221
 222 static inline void intel_rdt_sched_in(void) {}
 223
 224 #endif /* CONFIG_INTEL_RDT_A */
 225 #endif /* _ASM_X86_INTEL_RDT_H */