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 has not yet started */ 58 #define _THREAD_PRESTART (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 }; 126 127 struct _ready_q { 128 #ifndef CONFIG_SMP 129 /* always contains next thread to run: cannot be NULL */ 130 struct k_thread *cache; 131 #endif 132 133 #if defined(CONFIG_SCHED_DUMB) 134 sys_dlist_t runq; 135 #elif defined(CONFIG_SCHED_SCALABLE) 136 struct _priq_rb runq; 137 #elif defined(CONFIG_SCHED_MULTIQ) 138 struct _priq_mq runq; 139 #endif 140 }; 141 142 typedef struct _ready_q _ready_q_t; 143 144 struct _cpu { 145 /* nested interrupt count */ 146 uint32_t nested; 147 148 /* interrupt stack pointer base */ 149 char *irq_stack; 150 151 /* currently scheduled thread */ 152 struct k_thread *current; 153 154 /* one assigned idle thread per CPU */ 155 struct k_thread *idle_thread; 156 157 #ifdef CONFIG_SCHED_CPU_MASK_PIN_ONLY 158 struct _ready_q ready_q; 159 #endif 160 161 #if (CONFIG_NUM_METAIRQ_PRIORITIES > 0) && \ 162 (CONFIG_NUM_COOP_PRIORITIES > CONFIG_NUM_METAIRQ_PRIORITIES) 163 /* Coop thread preempted by current metairq, or NULL */ 164 struct k_thread *metairq_preempted; 165 #endif 166 167 uint8_t id; 168 169 #if defined(CONFIG_FPU_SHARING) 170 void *fp_ctx; 171 #endif 172 173 #ifdef CONFIG_SMP 174 /* True when _current is allowed to context switch */ 175 uint8_t swap_ok; 176 #endif 177 178 #ifdef CONFIG_SCHED_THREAD_USAGE 179 /* 180 * [usage0] is used as a timestamp to mark the beginning of an 181 * execution window. [0] is a special value indicating that it 182 * has been stopped (but not disabled). 183 */ 184 185 uint32_t usage0; 186 187 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL 188 struct k_cycle_stats *usage; 189 #endif 190 #endif 191 192 #ifdef CONFIG_OBJ_CORE_SYSTEM 193 struct k_obj_core obj_core; 194 #endif 195 196 /* Per CPU architecture specifics */ 197 struct _cpu_arch arch; 198 }; 199 200 typedef struct _cpu _cpu_t; 201 202 struct z_kernel { 203 struct _cpu cpus[CONFIG_MP_MAX_NUM_CPUS]; 204 205 #ifdef CONFIG_PM 206 int32_t idle; /* Number of ticks for kernel idling */ 207 #endif 208 209 /* 210 * ready queue: can be big, keep after small fields, since some 211 * assembly (e.g. ARC) are limited in the encoding of the offset 212 */ 213 #ifndef CONFIG_SCHED_CPU_MASK_PIN_ONLY 214 struct _ready_q ready_q; 215 #endif 216 217 #ifdef CONFIG_FPU_SHARING 218 /* 219 * A 'current_sse' field does not exist in addition to the 'current_fp' 220 * field since it's not possible to divide the IA-32 non-integer 221 * registers into 2 distinct blocks owned by differing threads. In 222 * other words, given that the 'fxnsave/fxrstor' instructions 223 * save/restore both the X87 FPU and XMM registers, it's not possible 224 * for a thread to only "own" the XMM registers. 225 */ 226 227 /* thread that owns the FP regs */ 228 struct k_thread *current_fp; 229 #endif 230 231 #if defined(CONFIG_THREAD_MONITOR) 232 struct k_thread *threads; /* singly linked list of ALL threads */ 233 #endif 234 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL 235 struct k_cycle_stats usage[CONFIG_MP_MAX_NUM_CPUS]; 236 #endif 237 238 #ifdef CONFIG_OBJ_CORE_SYSTEM 239 struct k_obj_core obj_core; 240 #endif 241 242 #if defined(CONFIG_SMP) && defined(CONFIG_SCHED_IPI_SUPPORTED) 243 /* Identify CPUs to send IPIs to at the next scheduling point */ 244 atomic_t pending_ipi; 245 #endif 246 }; 247 248 typedef struct z_kernel _kernel_t; 249 250 extern struct z_kernel _kernel; 251 252 extern atomic_t _cpus_active; 253 254 #ifdef CONFIG_SMP 255 256 /* True if the current context can be preempted and migrated to 257 * another SMP CPU. 258 */ 259 bool z_smp_cpu_mobile(void); 260 261 #define _current_cpu ({ __ASSERT_NO_MSG(!z_smp_cpu_mobile()); \ 262 arch_curr_cpu(); }) 263 #define _current k_sched_current_thread_query() 264 265 #else 266 #define _current_cpu (&_kernel.cpus[0]) 267 #define _current _kernel.cpus[0].current 268 #endif 269 270 /* kernel wait queue record */ 271 #ifdef CONFIG_WAITQ_SCALABLE 272 273 typedef struct { 274 struct _priq_rb waitq; 275 } _wait_q_t; 276 277 /* defined in kernel/priority_queues.c */ 278 bool z_priq_rb_lessthan(struct rbnode *a, struct rbnode *b); 279 280 #define Z_WAIT_Q_INIT(wait_q) { { { .lessthan_fn = z_priq_rb_lessthan } } } 281 282 #else 283 284 typedef struct { 285 sys_dlist_t waitq; 286 } _wait_q_t; 287 288 #define Z_WAIT_Q_INIT(wait_q) { SYS_DLIST_STATIC_INIT(&(wait_q)->waitq) } 289 290 #endif /* CONFIG_WAITQ_SCALABLE */ 291 292 /* kernel timeout record */ 293 struct _timeout; 294 typedef void (*_timeout_func_t)(struct _timeout *t); 295 296 struct _timeout { 297 sys_dnode_t node; 298 _timeout_func_t fn; 299 #ifdef CONFIG_TIMEOUT_64BIT 300 /* Can't use k_ticks_t for header dependency reasons */ 301 int64_t dticks; 302 #else 303 int32_t dticks; 304 #endif 305 }; 306 307 typedef void (*k_thread_timeslice_fn_t)(struct k_thread *thread, void *data); 308 309 #ifdef __cplusplus 310 } 311 #endif 312 313 #endif /* _ASMLANGUAGE */ 314 315 #endif /* ZEPHYR_KERNEL_INCLUDE_KERNEL_STRUCTS_H_ */ 316
