1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_RESCTRL_H 3 #define _ASM_X86_RESCTRL_H 4 5 #ifdef CONFIG_X86_CPU_RESCTRL 6 7 #include <linux/jump_label.h> 8 #include <linux/percpu.h> 9 #include <linux/resctrl_types.h> 10 #include <linux/sched.h> 11 12 /* 13 * This value can never be a valid CLOSID, and is used when mapping a 14 * (closid, rmid) pair to an index and back. On x86 only the RMID is 15 * needed. The index is a software defined value. 16 */ 17 #define X86_RESCTRL_EMPTY_CLOSID ((u32)~0) 18 19 /** 20 * struct resctrl_pqr_state - State cache for the PQR MSR 21 * @cur_rmid: The cached Resource Monitoring ID 22 * @cur_closid: The cached Class Of Service ID 23 * @default_rmid: The user assigned Resource Monitoring ID 24 * @default_closid: The user assigned cached Class Of Service ID 25 * 26 * The upper 32 bits of MSR_IA32_PQR_ASSOC contain closid and the 27 * lower 10 bits rmid. The update to MSR_IA32_PQR_ASSOC always 28 * contains both parts, so we need to cache them. This also 29 * stores the user configured per cpu CLOSID and RMID. 30 * 31 * The cache also helps to avoid pointless updates if the value does 32 * not change. 33 */ 34 struct resctrl_pqr_state { 35 u32 cur_rmid; 36 u32 cur_closid; 37 u32 default_rmid; 38 u32 default_closid; 39 }; 40 41 DECLARE_PER_CPU(struct resctrl_pqr_state, pqr_state); 42 43 extern bool rdt_alloc_capable; 44 extern bool rdt_mon_capable; 45 extern unsigned int rdt_mon_features; 46 47 DECLARE_STATIC_KEY_FALSE(rdt_enable_key); 48 DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key); 49 DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key); 50 51 static inline bool resctrl_arch_alloc_capable(void) 52 { 53 return rdt_alloc_capable; 54 } 55 56 static inline void resctrl_arch_enable_alloc(void) 57 { 58 static_branch_enable_cpuslocked(&rdt_alloc_enable_key); 59 static_branch_inc_cpuslocked(&rdt_enable_key); 60 } 61 62 static inline void resctrl_arch_disable_alloc(void) 63 { 64 static_branch_disable_cpuslocked(&rdt_alloc_enable_key); 65 static_branch_dec_cpuslocked(&rdt_enable_key); 66 } 67 68 static inline bool resctrl_arch_mon_capable(void) 69 { 70 return rdt_mon_capable; 71 } 72 73 static inline void resctrl_arch_enable_mon(void) 74 { 75 static_branch_enable_cpuslocked(&rdt_mon_enable_key); 76 static_branch_inc_cpuslocked(&rdt_enable_key); 77 } 78 79 static inline void resctrl_arch_disable_mon(void) 80 { 81 static_branch_disable_cpuslocked(&rdt_mon_enable_key); 82 static_branch_dec_cpuslocked(&rdt_enable_key); 83 } 84 85 static inline bool resctrl_arch_is_llc_occupancy_enabled(void) 86 { 87 return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID)); 88 } 89 90 static inline bool resctrl_arch_is_mbm_total_enabled(void) 91 { 92 return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID)); 93 } 94 95 static inline bool resctrl_arch_is_mbm_local_enabled(void) 96 { 97 return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID)); 98 } 99 100 /* 101 * __resctrl_sched_in() - Writes the task's CLOSid/RMID to IA32_PQR_MSR 102 * 103 * Following considerations are made so that this has minimal impact 104 * on scheduler hot path: 105 * - This will stay as no-op unless we are running on an Intel SKU 106 * which supports resource control or monitoring and we enable by 107 * mounting the resctrl file system. 108 * - Caches the per cpu CLOSid/RMID values and does the MSR write only 109 * when a task with a different CLOSid/RMID is scheduled in. 110 * - We allocate RMIDs/CLOSids globally in order to keep this as 111 * simple as possible. 112 * Must be called with preemption disabled. 113 */ 114 static inline void __resctrl_sched_in(struct task_struct *tsk) 115 { 116 struct resctrl_pqr_state *state = this_cpu_ptr(&pqr_state); 117 u32 closid = READ_ONCE(state->default_closid); 118 u32 rmid = READ_ONCE(state->default_rmid); 119 u32 tmp; 120 121 /* 122 * If this task has a closid/rmid assigned, use it. 123 * Else use the closid/rmid assigned to this cpu. 124 */ 125 if (static_branch_likely(&rdt_alloc_enable_key)) { 126 tmp = READ_ONCE(tsk->closid); 127 if (tmp) 128 closid = tmp; 129 } 130 131 if (static_branch_likely(&rdt_mon_enable_key)) { 132 tmp = READ_ONCE(tsk->rmid); 133 if (tmp) 134 rmid = tmp; 135 } 136 137 if (closid != state->cur_closid || rmid != state->cur_rmid) { 138 state->cur_closid = closid; 139 state->cur_rmid = rmid; 140 wrmsr(MSR_IA32_PQR_ASSOC, rmid, closid); 141 } 142 } 143 144 static inline unsigned int resctrl_arch_round_mon_val(unsigned int val) 145 { 146 unsigned int scale = boot_cpu_data.x86_cache_occ_scale; 147 148 /* h/w works in units of "boot_cpu_data.x86_cache_occ_scale" */ 149 val /= scale; 150 return val * scale; 151 } 152 153 static inline void resctrl_arch_set_cpu_default_closid_rmid(int cpu, u32 closid, 154 u32 rmid) 155 { 156 WRITE_ONCE(per_cpu(pqr_state.default_closid, cpu), closid); 157 WRITE_ONCE(per_cpu(pqr_state.default_rmid, cpu), rmid); 158 } 159 160 static inline void resctrl_arch_set_closid_rmid(struct task_struct *tsk, 161 u32 closid, u32 rmid) 162 { 163 WRITE_ONCE(tsk->closid, closid); 164 WRITE_ONCE(tsk->rmid, rmid); 165 } 166 167 static inline bool resctrl_arch_match_closid(struct task_struct *tsk, u32 closid) 168 { 169 return READ_ONCE(tsk->closid) == closid; 170 } 171 172 static inline bool resctrl_arch_match_rmid(struct task_struct *tsk, u32 ignored, 173 u32 rmid) 174 { 175 return READ_ONCE(tsk->rmid) == rmid; 176 } 177 178 static inline void resctrl_sched_in(struct task_struct *tsk) 179 { 180 if (static_branch_likely(&rdt_enable_key)) 181 __resctrl_sched_in(tsk); 182 } 183 184 static inline void resctrl_arch_rmid_idx_decode(u32 idx, u32 *closid, u32 *rmid) 185 { 186 *rmid = idx; 187 *closid = X86_RESCTRL_EMPTY_CLOSID; 188 } 189 190 static inline u32 resctrl_arch_rmid_idx_encode(u32 ignored, u32 rmid) 191 { 192 return rmid; 193 } 194 195 /* x86 can always read an rmid, nothing needs allocating */ 196 struct rdt_resource; 197 static inline void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid) 198 { 199 might_sleep(); 200 return NULL; 201 }; 202 203 static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid, 204 void *ctx) { }; 205 206 u64 resctrl_arch_get_prefetch_disable_bits(void); 207 int resctrl_arch_pseudo_lock_fn(void *_plr); 208 int resctrl_arch_measure_cycles_lat_fn(void *_plr); 209 int resctrl_arch_measure_l2_residency(void *_plr); 210 int resctrl_arch_measure_l3_residency(void *_plr); 211 void resctrl_cpu_detect(struct cpuinfo_x86 *c); 212 213 #else 214 215 static inline void resctrl_sched_in(struct task_struct *tsk) {} 216 static inline void resctrl_cpu_detect(struct cpuinfo_x86 *c) {} 217 218 #endif /* CONFIG_X86_CPU_RESCTRL */ 219 220 #endif /* _ASM_X86_RESCTRL_H */ 221