1 /*
2  * Copyright (c) 2016, Wind River Systems, Inc.
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #ifndef ZEPHYR_INCLUDE_KERNEL_THREAD_H_
8 #define ZEPHYR_INCLUDE_KERNEL_THREAD_H_
9 
10 #ifdef CONFIG_DEMAND_PAGING_THREAD_STATS
11 #include <zephyr/kernel/mm/demand_paging.h>
12 #endif /* CONFIG_DEMAND_PAGING_THREAD_STATS */
13 
14 #include <zephyr/kernel/stats.h>
15 #include <zephyr/arch/arch_interface.h>
16 
17 /**
18  * @typedef k_thread_entry_t
19  * @brief Thread entry point function type.
20  *
21  * A thread's entry point function is invoked when the thread starts executing.
22  * Up to 3 argument values can be passed to the function.
23  *
24  * The thread terminates execution permanently if the entry point function
25  * returns. The thread is responsible for releasing any shared resources
26  * it may own (such as mutexes and dynamically allocated memory), prior to
27  * returning.
28  *
29  * @param p1 First argument.
30  * @param p2 Second argument.
31  * @param p3 Third argument.
32  */
33 
34 #ifdef CONFIG_THREAD_MONITOR
35 struct __thread_entry {
36 	k_thread_entry_t pEntry;
37 	void *parameter1;
38 	void *parameter2;
39 	void *parameter3;
40 };
41 #endif /* CONFIG_THREAD_MONITOR */
42 
43 struct k_thread;
44 
45 /*
46  * This _pipe_desc structure is used by the pipes kernel module when
47  * CONFIG_PIPES has been selected.
48  */
49 
50 struct _pipe_desc {
51 	sys_dnode_t      node;
52 	unsigned char   *buffer;         /* Position in src/dest buffer */
53 	size_t           bytes_to_xfer;  /* # bytes left to transfer */
54 	struct k_thread *thread;         /* Back pointer to pended thread */
55 };
56 
57 /* can be used for creating 'dummy' threads, e.g. for pending on objects */
58 struct _thread_base {
59 
60 	/* this thread's entry in a ready/wait queue */
61 	union {
62 		sys_dnode_t qnode_dlist;
63 		struct rbnode qnode_rb;
64 	};
65 
66 	/* wait queue on which the thread is pended (needed only for
67 	 * trees, not dumb lists)
68 	 */
69 	_wait_q_t *pended_on;
70 
71 	/* user facing 'thread options'; values defined in include/kernel.h */
72 	uint8_t user_options;
73 
74 	/* thread state */
75 	uint8_t thread_state;
76 
77 	/*
78 	 * scheduler lock count and thread priority
79 	 *
80 	 * These two fields control the preemptibility of a thread.
81 	 *
82 	 * When the scheduler is locked, sched_locked is decremented, which
83 	 * means that the scheduler is locked for values from 0xff to 0x01. A
84 	 * thread is coop if its prio is negative, thus 0x80 to 0xff when
85 	 * looked at the value as unsigned.
86 	 *
87 	 * By putting them end-to-end, this means that a thread is
88 	 * non-preemptible if the bundled value is greater than or equal to
89 	 * 0x0080.
90 	 */
91 	union {
92 		struct {
93 #ifdef CONFIG_BIG_ENDIAN
94 			uint8_t sched_locked;
95 			int8_t prio;
96 #else /* Little Endian */
97 			int8_t prio;
98 			uint8_t sched_locked;
99 #endif /* CONFIG_BIG_ENDIAN */
100 		};
101 		uint16_t preempt;
102 	};
103 
104 #ifdef CONFIG_SCHED_DEADLINE
105 	int prio_deadline;
106 #endif /* CONFIG_SCHED_DEADLINE */
107 
108 	uint32_t order_key;
109 
110 #ifdef CONFIG_SMP
111 	/* True for the per-CPU idle threads */
112 	uint8_t is_idle;
113 
114 	/* CPU index on which thread was last run */
115 	uint8_t cpu;
116 
117 	/* Recursive count of irq_lock() calls */
118 	uint8_t global_lock_count;
119 
120 #endif /* CONFIG_SMP */
121 
122 #ifdef CONFIG_SCHED_CPU_MASK
123 	/* "May run on" bits for each CPU */
124 #if CONFIG_MP_MAX_NUM_CPUS <= 8
125 	uint8_t cpu_mask;
126 #else
127 	uint16_t cpu_mask;
128 #endif /* CONFIG_MP_MAX_NUM_CPUS */
129 #endif /* CONFIG_SCHED_CPU_MASK */
130 
131 	/* data returned by APIs */
132 	void *swap_data;
133 
134 #ifdef CONFIG_SYS_CLOCK_EXISTS
135 	/* this thread's entry in a timeout queue */
136 	struct _timeout timeout;
137 #endif /* CONFIG_SYS_CLOCK_EXISTS */
138 
139 #ifdef CONFIG_TIMESLICE_PER_THREAD
140 	int32_t slice_ticks;
141 	k_thread_timeslice_fn_t slice_expired;
142 	void *slice_data;
143 #endif /* CONFIG_TIMESLICE_PER_THREAD */
144 
145 #ifdef CONFIG_SCHED_THREAD_USAGE
146 	struct k_cycle_stats  usage;   /* Track thread usage statistics */
147 #endif /* CONFIG_SCHED_THREAD_USAGE */
148 };
149 
150 typedef struct _thread_base _thread_base_t;
151 
152 #if defined(CONFIG_THREAD_STACK_INFO)
153 /* Contains the stack information of a thread */
154 struct _thread_stack_info {
155 	/* Stack start - Represents the start address of the thread-writable
156 	 * stack area.
157 	 */
158 	uintptr_t start;
159 
160 	/* Thread writable stack buffer size. Represents the size of the actual
161 	 * buffer, starting from the 'start' member, that should be writable by
162 	 * the thread. This comprises of the thread stack area, any area reserved
163 	 * for local thread data storage, as well as any area left-out due to
164 	 * random adjustments applied to the initial thread stack pointer during
165 	 * thread initialization.
166 	 */
167 	size_t size;
168 
169 	/* Adjustment value to the size member, removing any storage
170 	 * used for TLS or random stack base offsets. (start + size - delta)
171 	 * is the initial stack pointer for a thread. May be 0.
172 	 */
173 	size_t delta;
174 
175 #if defined(CONFIG_THREAD_STACK_MEM_MAPPED)
176 	struct {
177 		/** Base address of the memory mapped thread stack */
178 		k_thread_stack_t *addr;
179 
180 		/** Size of whole mapped stack object */
181 		size_t sz;
182 	} mapped;
183 #endif /* CONFIG_THREAD_STACK_MEM_MAPPED */
184 };
185 
186 typedef struct _thread_stack_info _thread_stack_info_t;
187 #endif /* CONFIG_THREAD_STACK_INFO */
188 
189 #if defined(CONFIG_USERSPACE)
190 struct _mem_domain_info {
191 	/** memory domain queue node */
192 	sys_dnode_t mem_domain_q_node;
193 	/** memory domain of the thread */
194 	struct k_mem_domain *mem_domain;
195 };
196 
197 #endif /* CONFIG_USERSPACE */
198 
199 #ifdef CONFIG_THREAD_USERSPACE_LOCAL_DATA
200 struct _thread_userspace_local_data {
201 #if defined(CONFIG_ERRNO) && !defined(CONFIG_ERRNO_IN_TLS) && !defined(CONFIG_LIBC_ERRNO)
202 	int errno_var;
203 #endif /* CONFIG_ERRNO && !CONFIG_ERRNO_IN_TLS && !CONFIG_LIBC_ERRNO */
204 };
205 #endif /* CONFIG_THREAD_USERSPACE_LOCAL_DATA */
206 
207 typedef struct k_thread_runtime_stats {
208 #ifdef CONFIG_SCHED_THREAD_USAGE
209 	/*
210 	 * For CPU stats, execution_cycles is the sum of non-idle + idle cycles.
211 	 * For thread stats, execution_cycles = total_cycles.
212 	 */
213 	uint64_t execution_cycles;    /* total # of cycles (cpu: non-idle + idle) */
214 	uint64_t total_cycles;        /* total # of non-idle cycles */
215 #endif /* CONFIG_SCHED_THREAD_USAGE */
216 
217 #ifdef CONFIG_SCHED_THREAD_USAGE_ANALYSIS
218 	/*
219 	 * For threads, the following fields refer to the time spent executing
220 	 * as bounded by when the thread was scheduled in and scheduled out.
221 	 * For CPUs, the same fields refer to the time spent executing
222 	 * non-idle threads as bounded by the idle thread(s).
223 	 */
224 
225 	uint64_t current_cycles;      /* current # of non-idle cycles */
226 	uint64_t peak_cycles;         /* peak # of non-idle cycles */
227 	uint64_t average_cycles;      /* average # of non-idle cycles */
228 #endif /* CONFIG_SCHED_THREAD_USAGE_ANALYSIS */
229 
230 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL
231 	/*
232 	 * This field is always zero for individual threads. It only comes
233 	 * into play when gathering statistics for the CPU. In that case it
234 	 * represents the total number of cycles spent idling.
235 	 */
236 
237 	uint64_t idle_cycles;
238 #endif /* CONFIG_SCHED_THREAD_USAGE_ALL */
239 
240 #if defined(__cplusplus) && !defined(CONFIG_SCHED_THREAD_USAGE) &&                                 \
241 	!defined(CONFIG_SCHED_THREAD_USAGE_ANALYSIS) && !defined(CONFIG_SCHED_THREAD_USAGE_ALL)
242 	/* If none of the above Kconfig values are defined, this struct will have a size 0 in C
243 	 * which is not allowed in C++ (it'll have a size 1). To prevent this, we add a 1 byte dummy
244 	 * variable when the struct would otherwise be empty.
245 	 */
246 	uint8_t dummy;
247 #endif
248 }  k_thread_runtime_stats_t;
249 
250 struct z_poller {
251 	bool is_polling;
252 	uint8_t mode;
253 };
254 
255 /**
256  * @ingroup thread_apis
257  * Thread Structure
258  */
259 struct k_thread {
260 
261 	struct _thread_base base;
262 
263 	/** defined by the architecture, but all archs need these */
264 	struct _callee_saved callee_saved;
265 
266 	/** static thread init data */
267 	void *init_data;
268 
269 	/** threads waiting in k_thread_join() */
270 	_wait_q_t join_queue;
271 
272 #if defined(CONFIG_POLL)
273 	struct z_poller poller;
274 #endif /* CONFIG_POLL */
275 
276 #if defined(CONFIG_EVENTS)
277 	struct k_thread *next_event_link;
278 
279 	uint32_t   events;
280 	uint32_t   event_options;
281 
282 	/** true if timeout should not wake the thread */
283 	bool no_wake_on_timeout;
284 #endif /* CONFIG_EVENTS */
285 
286 #if defined(CONFIG_THREAD_MONITOR)
287 	/** thread entry and parameters description */
288 	struct __thread_entry entry;
289 
290 	/** next item in list of all threads */
291 	struct k_thread *next_thread;
292 #endif /* CONFIG_THREAD_MONITOR */
293 
294 #if defined(CONFIG_THREAD_NAME)
295 	/** Thread name */
296 	char name[CONFIG_THREAD_MAX_NAME_LEN];
297 #endif /* CONFIG_THREAD_NAME */
298 
299 #ifdef CONFIG_THREAD_CUSTOM_DATA
300 	/** crude thread-local storage */
301 	void *custom_data;
302 #endif /* CONFIG_THREAD_CUSTOM_DATA */
303 
304 #ifdef CONFIG_THREAD_USERSPACE_LOCAL_DATA
305 	struct _thread_userspace_local_data *userspace_local_data;
306 #endif /* CONFIG_THREAD_USERSPACE_LOCAL_DATA */
307 
308 #if defined(CONFIG_ERRNO) && !defined(CONFIG_ERRNO_IN_TLS) && !defined(CONFIG_LIBC_ERRNO)
309 #ifndef CONFIG_USERSPACE
310 	/** per-thread errno variable */
311 	int errno_var;
312 #endif /* CONFIG_USERSPACE */
313 #endif /* CONFIG_ERRNO && !CONFIG_ERRNO_IN_TLS && !CONFIG_LIBC_ERRNO */
314 
315 #if defined(CONFIG_THREAD_STACK_INFO)
316 	/** Stack Info */
317 	struct _thread_stack_info stack_info;
318 #endif /* CONFIG_THREAD_STACK_INFO */
319 
320 #if defined(CONFIG_USERSPACE)
321 	/** memory domain info of the thread */
322 	struct _mem_domain_info mem_domain_info;
323 
324 	/**
325 	 * Base address of thread stack.
326 	 *
327 	 * If memory mapped stack (CONFIG_THREAD_STACK_MEM_MAPPED)
328 	 * is enabled, this is the physical address of the stack.
329 	 */
330 	k_thread_stack_t *stack_obj;
331 
332 	/** current syscall frame pointer */
333 	void *syscall_frame;
334 #endif /* CONFIG_USERSPACE */
335 
336 
337 #if defined(CONFIG_USE_SWITCH)
338 	/* When using __switch() a few previously arch-specific items
339 	 * become part of the core OS
340 	 */
341 
342 	/** z_swap() return value */
343 	int swap_retval;
344 
345 	/** Context handle returned via arch_switch() */
346 	void *switch_handle;
347 #endif /* CONFIG_USE_SWITCH */
348 	/** resource pool */
349 	struct k_heap *resource_pool;
350 
351 #if defined(CONFIG_THREAD_LOCAL_STORAGE)
352 	/* Pointer to arch-specific TLS area */
353 	uintptr_t tls;
354 #endif /* CONFIG_THREAD_LOCAL_STORAGE */
355 
356 #ifdef CONFIG_DEMAND_PAGING_THREAD_STATS
357 	/** Paging statistics */
358 	struct k_mem_paging_stats_t paging_stats;
359 #endif /* CONFIG_DEMAND_PAGING_THREAD_STATS */
360 
361 #ifdef CONFIG_PIPES
362 	/** Pipe descriptor used with blocking k_pipe operations */
363 	struct _pipe_desc pipe_desc;
364 #endif /* CONFIG_PIPES */
365 
366 #ifdef CONFIG_OBJ_CORE_THREAD
367 	struct k_obj_core  obj_core;
368 #endif /* CONFIG_OBJ_CORE_THREAD */
369 
370 #ifdef CONFIG_SMP
371 	/** threads waiting in k_thread_suspend() */
372 	_wait_q_t  halt_queue;
373 #endif /* CONFIG_SMP */
374 
375 	/** arch-specifics: must always be at the end */
376 	struct _thread_arch arch;
377 };
378 
379 typedef struct k_thread _thread_t;
380 typedef struct k_thread *k_tid_t;
381 
382 #endif /* ZEPHYR_INCLUDE_KERNEL_THREAD_H_ */
383