1 /* 2 * Copyright (c) 2016 Wind River Systems, Inc. 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 /* 8 * The purpose of this file is to provide essential/minimal kernel structure 9 * definitions, so that they can be used without including kernel.h. 10 * 11 * The following rules must be observed: 12 * 1. kernel_structs.h shall not depend on kernel.h both directly and 13 * indirectly (i.e. it shall not include any header files that include 14 * kernel.h in their dependency chain). 15 * 2. kernel.h shall imply kernel_structs.h, such that it shall not be 16 * necessary to include kernel_structs.h explicitly when kernel.h is 17 * included. 18 */ 19 20 #ifndef ZEPHYR_KERNEL_INCLUDE_KERNEL_STRUCTS_H_ 21 #define ZEPHYR_KERNEL_INCLUDE_KERNEL_STRUCTS_H_ 22 23 #if !defined(_ASMLANGUAGE) 24 #include <zephyr/sys/atomic.h> 25 #include <zephyr/types.h> 26 #include <zephyr/sys/dlist.h> 27 #include <zephyr/sys/util.h> 28 #include <zephyr/sys/sys_heap.h> 29 #include <zephyr/arch/structs.h> 30 #include <zephyr/kernel/stats.h> 31 #include <zephyr/kernel/obj_core.h> 32 #include <zephyr/sys/rb.h> 33 #endif 34 35 #define K_NUM_THREAD_PRIO (CONFIG_NUM_PREEMPT_PRIORITIES + CONFIG_NUM_COOP_PRIORITIES + 1) 36 #define PRIQ_BITMAP_SIZE (DIV_ROUND_UP(K_NUM_THREAD_PRIO, BITS_PER_LONG)) 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /* 43 * Bitmask definitions for the struct k_thread.thread_state field. 44 * 45 * Must be before kernel_arch_data.h because it might need them to be already 46 * defined. 47 */ 48 49 /* states: common uses low bits, arch-specific use high bits */ 50 51 /* Not a real thread */ 52 #define _THREAD_DUMMY (BIT(0)) 53 54 /* Thread is waiting on an object */ 55 #define _THREAD_PENDING (BIT(1)) 56 57 /* Thread is sleeping */ 58 #define _THREAD_SLEEPING (BIT(2)) 59 60 /* Thread has terminated */ 61 #define _THREAD_DEAD (BIT(3)) 62 63 /* Thread is suspended */ 64 #define _THREAD_SUSPENDED (BIT(4)) 65 66 /* Thread is in the process of aborting */ 67 #define _THREAD_ABORTING (BIT(5)) 68 69 /* Thread is in the process of suspending */ 70 #define _THREAD_SUSPENDING (BIT(6)) 71 72 /* Thread is present in the ready queue */ 73 #define _THREAD_QUEUED (BIT(7)) 74 75 /* end - states */ 76 77 #ifdef CONFIG_STACK_SENTINEL 78 /* Magic value in lowest bytes of the stack */ 79 #define STACK_SENTINEL 0xF0F0F0F0 80 #endif 81 82 /* lowest value of _thread_base.preempt at which a thread is non-preemptible */ 83 #define _NON_PREEMPT_THRESHOLD 0x0080U 84 85 /* highest value of _thread_base.preempt at which a thread is preemptible */ 86 #define _PREEMPT_THRESHOLD (_NON_PREEMPT_THRESHOLD - 1U) 87 88 #if !defined(_ASMLANGUAGE) 89 90 /* Two abstractions are defined here for "thread priority queues". 91 * 92 * One is a "dumb" list implementation appropriate for systems with 93 * small numbers of threads and sensitive to code size. It is stored 94 * in sorted order, taking an O(N) cost every time a thread is added 95 * to the list. This corresponds to the way the original _wait_q_t 96 * abstraction worked and is very fast as long as the number of 97 * threads is small. 98 * 99 * The other is a balanced tree "fast" implementation with rather 100 * larger code size (due to the data structure itself, the code here 101 * is just stubs) and higher constant-factor performance overhead, but 102 * much better O(logN) scaling in the presence of large number of 103 * threads. 104 * 105 * Each can be used for either the wait_q or system ready queue, 106 * configurable at build time. 107 */ 108 109 struct _priq_rb { 110 struct rbtree tree; 111 int next_order_key; 112 }; 113 114 115 /* Traditional/textbook "multi-queue" structure. Separate lists for a 116 * small number (max 32 here) of fixed priorities. This corresponds 117 * to the original Zephyr scheduler. RAM requirements are 118 * comparatively high, but performance is very fast. Won't work with 119 * features like deadline scheduling which need large priority spaces 120 * to represent their requirements. 121 */ 122 struct _priq_mq { 123 sys_dlist_t queues[K_NUM_THREAD_PRIO]; 124 unsigned long bitmask[PRIQ_BITMAP_SIZE]; 125 #ifndef CONFIG_SMP 126 unsigned int cached_queue_index; 127 #endif 128 }; 129 130 struct _ready_q { 131 #ifndef CONFIG_SMP 132 /* always contains next thread to run: cannot be NULL */ 133 struct k_thread *cache; 134 #endif 135 136 #if defined(CONFIG_SCHED_SIMPLE) 137 sys_dlist_t runq; 138 #elif defined(CONFIG_SCHED_SCALABLE) 139 struct _priq_rb runq; 140 #elif defined(CONFIG_SCHED_MULTIQ) 141 struct _priq_mq runq; 142 #endif 143 }; 144 145 typedef struct _ready_q _ready_q_t; 146 147 struct _cpu { 148 /* nested interrupt count */ 149 uint32_t nested; 150 151 /* interrupt stack pointer base */ 152 char *irq_stack; 153 154 /* currently scheduled thread */ 155 struct k_thread *current; 156 157 /* one assigned idle thread per CPU */ 158 struct k_thread *idle_thread; 159 160 #ifdef CONFIG_SCHED_CPU_MASK_PIN_ONLY 161 struct _ready_q ready_q; 162 #endif 163 164 #if (CONFIG_NUM_METAIRQ_PRIORITIES > 0) && \ 165 (CONFIG_NUM_COOP_PRIORITIES > CONFIG_NUM_METAIRQ_PRIORITIES) 166 /* Coop thread preempted by current metairq, or NULL */ 167 struct k_thread *metairq_preempted; 168 #endif 169 170 uint8_t id; 171 172 #if defined(CONFIG_FPU_SHARING) 173 void *fp_ctx; 174 #endif 175 176 #ifdef CONFIG_SMP 177 /* True when _current is allowed to context switch */ 178 uint8_t swap_ok; 179 #endif 180 181 #ifdef CONFIG_SCHED_THREAD_USAGE 182 /* 183 * [usage0] is used as a timestamp to mark the beginning of an 184 * execution window. [0] is a special value indicating that it 185 * has been stopped (but not disabled). 186 */ 187 188 uint32_t usage0; 189 190 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL 191 struct k_cycle_stats *usage; 192 #endif 193 #endif 194 195 #ifdef CONFIG_OBJ_CORE_SYSTEM 196 struct k_obj_core obj_core; 197 #endif 198 199 /* Per CPU architecture specifics */ 200 struct _cpu_arch arch; 201 }; 202 203 typedef struct _cpu _cpu_t; 204 205 struct z_kernel { 206 struct _cpu cpus[CONFIG_MP_MAX_NUM_CPUS]; 207 208 #ifdef CONFIG_PM 209 int32_t idle; /* Number of ticks for kernel idling */ 210 #endif 211 212 /* 213 * ready queue: can be big, keep after small fields, since some 214 * assembly (e.g. ARC) are limited in the encoding of the offset 215 */ 216 #ifndef CONFIG_SCHED_CPU_MASK_PIN_ONLY 217 struct _ready_q ready_q; 218 #endif 219 220 #if defined(CONFIG_THREAD_MONITOR) 221 struct k_thread *threads; /* singly linked list of ALL threads */ 222 #endif 223 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL 224 struct k_cycle_stats usage[CONFIG_MP_MAX_NUM_CPUS]; 225 #endif 226 227 #ifdef CONFIG_OBJ_CORE_SYSTEM 228 struct k_obj_core obj_core; 229 #endif 230 231 #if defined(CONFIG_SMP) && defined(CONFIG_SCHED_IPI_SUPPORTED) 232 /* Identify CPUs to send IPIs to at the next scheduling point */ 233 atomic_t pending_ipi; 234 #endif 235 }; 236 237 typedef struct z_kernel _kernel_t; 238 239 extern struct z_kernel _kernel; 240 241 extern atomic_t _cpus_active; 242 243 #ifdef CONFIG_SMP 244 245 /* True if the current context can be preempted and migrated to 246 * another SMP CPU. 247 */ 248 bool z_smp_cpu_mobile(void); 249 #define _current_cpu ({ __ASSERT_NO_MSG(!z_smp_cpu_mobile()); \ 250 arch_curr_cpu(); }) 251 252 __attribute_const__ struct k_thread *z_smp_current_get(void); 253 #define _current z_smp_current_get() 254 255 #else 256 #define _current_cpu (&_kernel.cpus[0]) 257 #define _current _kernel.cpus[0].current 258 #endif 259 260 /* This is always invoked from a context where preemption is disabled */ 261 #define z_current_thread_set(thread) ({ _current_cpu->current = (thread); }) 262 263 #ifdef CONFIG_ARCH_HAS_CUSTOM_CURRENT_IMPL 264 #undef _current 265 #define _current arch_current_thread() 266 #undef z_current_thread_set 267 #define z_current_thread_set(thread) \ 268 arch_current_thread_set(({ _current_cpu->current = (thread); })) 269 #endif 270 271 /* kernel wait queue record */ 272 #ifdef CONFIG_WAITQ_SCALABLE 273 274 typedef struct { 275 struct _priq_rb waitq; 276 } _wait_q_t; 277 278 /* defined in kernel/priority_queues.c */ 279 bool z_priq_rb_lessthan(struct rbnode *a, struct rbnode *b); 280 281 #define Z_WAIT_Q_INIT(wait_q) { { { .lessthan_fn = z_priq_rb_lessthan } } } 282 283 #else 284 285 typedef struct { 286 sys_dlist_t waitq; 287 } _wait_q_t; 288 289 #define Z_WAIT_Q_INIT(wait_q) { SYS_DLIST_STATIC_INIT(&(wait_q)->waitq) } 290 291 #endif /* CONFIG_WAITQ_SCALABLE */ 292 293 /* kernel timeout record */ 294 struct _timeout; 295 typedef void (*_timeout_func_t)(struct _timeout *t); 296 297 struct _timeout { 298 sys_dnode_t node; 299 _timeout_func_t fn; 300 #ifdef CONFIG_TIMEOUT_64BIT 301 /* Can't use k_ticks_t for header dependency reasons */ 302 int64_t dticks; 303 #else 304 int32_t dticks; 305 #endif 306 }; 307 308 typedef void (*k_thread_timeslice_fn_t)(struct k_thread *thread, void *data); 309 310 #ifdef __cplusplus 311 } 312 #endif 313 314 #endif /* _ASMLANGUAGE */ 315 316 #endif /* ZEPHYR_KERNEL_INCLUDE_KERNEL_STRUCTS_H_ */ 317
