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pigweed / third_party / github / zephyrproject-rtos / zephyr / 44e8b69ecd97ed7e9792097b751a802a5dbe137c / . / include / kernel.h
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/*
* Copyright (c) 2016, Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
*
* @brief Public kernel APIs.
*/
#ifndef _kernel__h_
#define _kernel__h_
#if !defined(_ASMLANGUAGE)
#include <stddef.h>
#include <zephyr/types.h>
#include <limits.h>
#include <toolchain.h>
#include <linker/sections.h>
#include <atomic.h>
#include <errno.h>
#include <misc/__assert.h>
#include <misc/dlist.h>
#include <misc/slist.h>
#include <misc/util.h>
#include <kernel_version.h>
#include <drivers/rand32.h>
#include <kernel_arch_thread.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Kernel APIs
* @defgroup kernel_apis Kernel APIs
* @{
* @}
*/
#ifdef CONFIG_KERNEL_DEBUG
#include <misc/printk.h>
#define K_DEBUG(fmt, ...) printk("[%s] " fmt, __func__, ##__VA_ARGS__)
#else
#define K_DEBUG(fmt, ...)
#endif
#if defined(CONFIG_COOP_ENABLED) && defined(CONFIG_PREEMPT_ENABLED)
#define _NUM_COOP_PRIO (CONFIG_NUM_COOP_PRIORITIES)
#define _NUM_PREEMPT_PRIO (CONFIG_NUM_PREEMPT_PRIORITIES + 1)
#elif defined(CONFIG_COOP_ENABLED)
#define _NUM_COOP_PRIO (CONFIG_NUM_COOP_PRIORITIES + 1)
#define _NUM_PREEMPT_PRIO (0)
#elif defined(CONFIG_PREEMPT_ENABLED)
#define _NUM_COOP_PRIO (0)
#define _NUM_PREEMPT_PRIO (CONFIG_NUM_PREEMPT_PRIORITIES + 1)
#else
#error "invalid configuration"
#endif
#define K_PRIO_COOP(x) (-(_NUM_COOP_PRIO - (x)))
#define K_PRIO_PREEMPT(x) (x)
#define K_ANY NULL
#define K_END NULL
#if defined(CONFIG_COOP_ENABLED) && defined(CONFIG_PREEMPT_ENABLED)
#define K_HIGHEST_THREAD_PRIO (-CONFIG_NUM_COOP_PRIORITIES)
#elif defined(CONFIG_COOP_ENABLED)
#define K_HIGHEST_THREAD_PRIO (-CONFIG_NUM_COOP_PRIORITIES - 1)
#elif defined(CONFIG_PREEMPT_ENABLED)
#define K_HIGHEST_THREAD_PRIO 0
#else
#error "invalid configuration"
#endif
#ifdef CONFIG_PREEMPT_ENABLED
#define K_LOWEST_THREAD_PRIO CONFIG_NUM_PREEMPT_PRIORITIES
#else
#define K_LOWEST_THREAD_PRIO -1
#endif
#define K_IDLE_PRIO K_LOWEST_THREAD_PRIO
#define K_HIGHEST_APPLICATION_THREAD_PRIO (K_HIGHEST_THREAD_PRIO)
#define K_LOWEST_APPLICATION_THREAD_PRIO (K_LOWEST_THREAD_PRIO - 1)
typedef sys_dlist_t _wait_q_t;
#ifdef CONFIG_OBJECT_TRACING
#define _OBJECT_TRACING_NEXT_PTR(type) struct type *__next
#define _OBJECT_TRACING_INIT .__next = NULL,
#else
#define _OBJECT_TRACING_INIT
#define _OBJECT_TRACING_NEXT_PTR(type)
#endif
#ifdef CONFIG_POLL
#define _POLL_EVENT_OBJ_INIT(obj) \
.poll_events = SYS_DLIST_STATIC_INIT(&obj.poll_events),
#define _POLL_EVENT sys_dlist_t poll_events
#else
#define _POLL_EVENT_OBJ_INIT(obj)
#define _POLL_EVENT
#endif
struct k_thread;
struct k_mutex;
struct k_sem;
struct k_alert;
struct k_msgq;
struct k_mbox;
struct k_pipe;
struct k_queue;
struct k_fifo;
struct k_lifo;
struct k_stack;
struct k_mem_slab;
struct k_mem_pool;
struct k_timer;
struct k_poll_event;
struct k_poll_signal;
/* timeouts */
struct _timeout;
typedef void (*_timeout_func_t)(struct _timeout *t);
struct _timeout {
sys_dnode_t node;
struct k_thread *thread;
sys_dlist_t *wait_q;
s32_t delta_ticks_from_prev;
_timeout_func_t func;
};
extern s32_t _timeout_remaining_get(struct _timeout *timeout);
/* Threads */
typedef void (*_thread_entry_t)(void *, void *, void *);
#ifdef CONFIG_THREAD_MONITOR
struct __thread_entry {
_thread_entry_t pEntry;
void *parameter1;
void *parameter2;
void *parameter3;
};
#endif
/* can be used for creating 'dummy' threads, e.g. for pending on objects */
struct _thread_base {
/* this thread's entry in a ready/wait queue */
sys_dnode_t k_q_node;
/* user facing 'thread options'; values defined in include/kernel.h */
u8_t user_options;
/* thread state */
u8_t thread_state;
/*
* scheduler lock count and thread priority
*
* These two fields control the preemptibility of a thread.
*
* When the scheduler is locked, sched_locked is decremented, which
* means that the scheduler is locked for values from 0xff to 0x01. A
* thread is coop if its prio is negative, thus 0x80 to 0xff when
* looked at the value as unsigned.
*
* By putting them end-to-end, this means that a thread is
* non-preemptible if the bundled value is greater than or equal to
* 0x0080.
*/
union {
struct {
#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
u8_t sched_locked;
s8_t prio;
#else /* LITTLE and PDP */
s8_t prio;
u8_t sched_locked;
#endif
};
u16_t preempt;
};
/* data returned by APIs */
void *swap_data;
#ifdef CONFIG_SYS_CLOCK_EXISTS
/* this thread's entry in a timeout queue */
struct _timeout timeout;
#endif
};
typedef struct _thread_base _thread_base_t;
#if defined(CONFIG_THREAD_STACK_INFO)
/* Contains the stack information of a thread */
struct _thread_stack_info {
/* Stack Start */
u32_t start;
/* Stack Size */
u32_t size;
};
typedef struct _thread_stack_info _thread_stack_info_t;
#endif /* CONFIG_THREAD_STACK_INFO */
struct k_thread {
struct _thread_base base;
/* defined by the architecture, but all archs need these */
struct _caller_saved caller_saved;
struct _callee_saved callee_saved;
/* static thread init data */
void *init_data;
/* abort function */
void (*fn_abort)(void);
#if defined(CONFIG_THREAD_MONITOR)
/* thread entry and parameters description */
struct __thread_entry *entry;
/* next item in list of all threads */
struct k_thread *next_thread;
#endif
#ifdef CONFIG_THREAD_CUSTOM_DATA
/* crude thread-local storage */
void *custom_data;
#endif
#ifdef CONFIG_ERRNO
/* per-thread errno variable */
int errno_var;
#endif
#if defined(CONFIG_THREAD_STACK_INFO)
/* Stack Info */
struct _thread_stack_info stack_info;
#endif /* CONFIG_THREAD_STACK_INFO */
/* arch-specifics: must always be at the end */
struct _thread_arch arch;
};
typedef struct k_thread _thread_t;
typedef struct k_thread *k_tid_t;
#define tcs k_thread
enum execution_context_types {
K_ISR = 0,
K_COOP_THREAD,
K_PREEMPT_THREAD,
};
/**
* @defgroup profiling_apis Profiling APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Analyze the main, idle, interrupt and system workqueue call stacks
*
* This routine calls @ref STACK_ANALYZE on the 4 call stacks declared and
* maintained by the kernel. The sizes of those 4 call stacks are defined by:
*
* CONFIG_MAIN_STACK_SIZE
* CONFIG_IDLE_STACK_SIZE
* CONFIG_ISR_STACK_SIZE
* CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE
*
* @note CONFIG_INIT_STACKS and CONFIG_PRINTK must be set for this function to
* produce output.
*
* @return N/A
*/
extern void k_call_stacks_analyze(void);
/**
* @} end defgroup profiling_apis
*/
/**
* @defgroup thread_apis Thread APIs
* @ingroup kernel_apis
* @{
*/
/**
* @typedef k_thread_entry_t
* @brief Thread entry point function type.
*
* A thread's entry point function is invoked when the thread starts executing.
* Up to 3 argument values can be passed to the function.
*
* The thread terminates execution permanently if the entry point function
* returns. The thread is responsible for releasing any shared resources
* it may own (such as mutexes and dynamically allocated memory), prior to
* returning.
*
* @param p1 First argument.
* @param p2 Second argument.
* @param p3 Third argument.
*
* @return N/A
*/
typedef void (*k_thread_entry_t)(void *p1, void *p2, void *p3);
#endif /* !_ASMLANGUAGE */
/*
* Thread user options. May be needed by assembly code. Common part uses low
* bits, arch-specific use high bits.
*/
/* system thread that must not abort */
#define K_ESSENTIAL (1 << 0)
#if defined(CONFIG_FP_SHARING)
/* thread uses floating point registers */
#define K_FP_REGS (1 << 1)
#endif
#ifdef CONFIG_X86
/* x86 Bitmask definitions for threads user options */
#if defined(CONFIG_FP_SHARING) && defined(CONFIG_SSE)
/* thread uses SSEx (and also FP) registers */
#define K_SSE_REGS (1 << 7)
#endif
#endif
/* end - thread options */
#if !defined(_ASMLANGUAGE)
/* Using typedef deliberately here, this is quite intended to be an opaque
* type. K_THREAD_STACK_BUFFER() should be used to access the data within.
*
* The purpose of this data type is to clearly distinguish between the
* declared symbol for a stack (of type k_thread_stack_t) and the underlying
* buffer which composes the stack data actually used by the underlying
* thread; they cannot be used interchangably as some arches precede the
* stack buffer region with guard areas that trigger a MPU or MMU fault
* if written to.
*
* APIs that want to work with the buffer inside should continue to use
* char *.
*
* Stacks should always be created with K_THREAD_STACK_DEFINE().
*/
struct __packed _k_thread_stack_element {
char data;
};
typedef struct _k_thread_stack_element *k_thread_stack_t;
/**
* @brief Spawn a thread.
*
* This routine initializes a thread, then schedules it for execution.
*
* The new thread may be scheduled for immediate execution or a delayed start.
* If the newly spawned thread does not have a delayed start the kernel
* scheduler may preempt the current thread to allow the new thread to
* execute.
*
* Kernel data structures for bookkeeping and context storage for this thread
* will be placed at the beginning of the thread's stack memory region and may
* become corrupted if too much of the stack is used. This function has been
* deprecated in favor of k_thread_create() to give the user more control on
* where these data structures reside.
*
* Thread options are architecture-specific, and can include K_ESSENTIAL,
* K_FP_REGS, and K_SSE_REGS. Multiple options may be specified by separating
* them using "|" (the logical OR operator).
*
* The stack itself should be declared with K_THREAD_STACK_DEFINE or variant
* macros. The stack size parameter should either be a defined constant
* also passed to K_THREAD_STACK_DEFINE, or the value of K_THREAD_STACK_SIZEOF.
* Do not use regular C sizeof().
*
* @param stack Pointer to the stack space.
* @param stack_size Stack size in bytes.
* @param entry Thread entry function.
* @param p1 1st entry point parameter.
* @param p2 2nd entry point parameter.
* @param p3 3rd entry point parameter.
* @param prio Thread priority.
* @param options Thread options.
* @param delay Scheduling delay (in milliseconds), or K_NO_WAIT (for no delay).
*
* @return ID of new thread.
*/
extern __deprecated k_tid_t k_thread_spawn(k_thread_stack_t stack,
size_t stack_size, k_thread_entry_t entry,
void *p1, void *p2, void *p3,
int prio, u32_t options, s32_t delay);
/**
* @brief Create a thread.
*
* This routine initializes a thread, then schedules it for execution.
*
* The new thread may be scheduled for immediate execution or a delayed start.
* If the newly spawned thread does not have a delayed start the kernel
* scheduler may preempt the current thread to allow the new thread to
* execute.
*
* Thread options are architecture-specific, and can include K_ESSENTIAL,
* K_FP_REGS, and K_SSE_REGS. Multiple options may be specified by separating
* them using "|" (the logical OR operator).
*
* Historically, users often would use the beginning of the stack memory region
* to store the struct k_thread data, although corruption will occur if the
* stack overflows this region and stack protection features may not detect this
* situation.
*
* @param new_thread Pointer to uninitialized struct k_thread
* @param stack Pointer to the stack space.
* @param stack_size Stack size in bytes.
* @param entry Thread entry function.
* @param p1 1st entry point parameter.
* @param p2 2nd entry point parameter.
* @param p3 3rd entry point parameter.
* @param prio Thread priority.
* @param options Thread options.
* @param delay Scheduling delay (in milliseconds), or K_NO_WAIT (for no delay).
*
* @return ID of new thread.
*/
extern k_tid_t k_thread_create(struct k_thread *new_thread,
k_thread_stack_t stack,
size_t stack_size,
void (*entry)(void *, void *, void*),
void *p1, void *p2, void *p3,
int prio, u32_t options, s32_t delay);
/**
* @brief Put the current thread to sleep.
*
* This routine puts the current thread to sleep for @a duration
* milliseconds.
*
* @param duration Number of milliseconds to sleep.
*
* @return N/A
*/
extern void k_sleep(s32_t duration);
/**
* @brief Cause the current thread to busy wait.
*
* This routine causes the current thread to execute a "do nothing" loop for
* @a usec_to_wait microseconds.
*
* @return N/A
*/
extern void k_busy_wait(u32_t usec_to_wait);
/**
* @brief Yield the current thread.
*
* This routine causes the current thread to yield execution to another
* thread of the same or higher priority. If there are no other ready threads
* of the same or higher priority, the routine returns immediately.
*
* @return N/A
*/
extern void k_yield(void);
/**
* @brief Wake up a sleeping thread.
*
* This routine prematurely wakes up @a thread from sleeping.
*
* If @a thread is not currently sleeping, the routine has no effect.
*
* @param thread ID of thread to wake.
*
* @return N/A
*/
extern void k_wakeup(k_tid_t thread);
/**
* @brief Get thread ID of the current thread.
*
* @return ID of current thread.
*/
extern k_tid_t k_current_get(void);
/**
* @brief Cancel thread performing a delayed start.
*
* This routine prevents @a thread from executing if it has not yet started
* execution. The thread must be re-spawned before it will execute.
*
* @param thread ID of thread to cancel.
*
* @retval 0 Thread spawning canceled.
* @retval -EINVAL Thread has already started executing.
*/
extern int k_thread_cancel(k_tid_t thread);
/**
* @brief Abort a thread.
*
* This routine permanently stops execution of @a thread. The thread is taken
* off all kernel queues it is part of (i.e. the ready queue, the timeout
* queue, or a kernel object wait queue). However, any kernel resources the
* thread might currently own (such as mutexes or memory blocks) are not
* released. It is the responsibility of the caller of this routine to ensure
* all necessary cleanup is performed.
*
* @param thread ID of thread to abort.
*
* @return N/A
*/
extern void k_thread_abort(k_tid_t thread);
/**
* @cond INTERNAL_HIDDEN
*/
/* timeout has timed out and is not on _timeout_q anymore */
#define _EXPIRED (-2)
/* timeout is not in use */
#define _INACTIVE (-1)
struct _static_thread_data {
struct k_thread *init_thread;
k_thread_stack_t init_stack;
unsigned int init_stack_size;
void (*init_entry)(void *, void *, void *);
void *init_p1;
void *init_p2;
void *init_p3;
int init_prio;
u32_t init_options;
s32_t init_delay;
void (*init_abort)(void);
u32_t init_groups;
};
#define _THREAD_INITIALIZER(thread, stack, stack_size, \
entry, p1, p2, p3, \
prio, options, delay, abort, groups) \
{ \
.init_thread = (thread), \
.init_stack = (stack), \
.init_stack_size = (stack_size), \
.init_entry = (void (*)(void *, void *, void *))entry, \
.init_p1 = (void *)p1, \
.init_p2 = (void *)p2, \
.init_p3 = (void *)p3, \
.init_prio = (prio), \
.init_options = (options), \
.init_delay = (delay), \
.init_abort = (abort), \
.init_groups = (groups), \
}
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @brief Statically define and initialize a thread.
*
* The thread may be scheduled for immediate execution or a delayed start.
*
* Thread options are architecture-specific, and can include K_ESSENTIAL,
* K_FP_REGS, and K_SSE_REGS. Multiple options may be specified by separating
* them using "|" (the logical OR operator).
*
* The ID of the thread can be accessed using:
*
* @code extern const k_tid_t <name>; @endcode
*
* @param name Name of the thread.
* @param stack_size Stack size in bytes.
* @param entry Thread entry function.
* @param p1 1st entry point parameter.
* @param p2 2nd entry point parameter.
* @param p3 3rd entry point parameter.
* @param prio Thread priority.
* @param options Thread options.
* @param delay Scheduling delay (in milliseconds), or K_NO_WAIT (for no delay).
*
* @internal It has been observed that the x86 compiler by default aligns
* these _static_thread_data structures to 32-byte boundaries, thereby
* wasting space. To work around this, force a 4-byte alignment.
*/
#define K_THREAD_DEFINE(name, stack_size, \
entry, p1, p2, p3, \
prio, options, delay) \
K_THREAD_STACK_DEFINE(_k_thread_stack_##name, stack_size); \
struct k_thread _k_thread_obj_##name; \
struct _static_thread_data _k_thread_data_##name __aligned(4) \
__in_section(_static_thread_data, static, name) = \
_THREAD_INITIALIZER(&_k_thread_obj_##name, \
_k_thread_stack_##name, stack_size, \
entry, p1, p2, p3, prio, options, delay, \
NULL, 0); \
const k_tid_t name = (k_tid_t)&_k_thread_obj_##name
/**
* @brief Get a thread's priority.
*
* This routine gets the priority of @a thread.
*
* @param thread ID of thread whose priority is needed.
*
* @return Priority of @a thread.
*/
extern int k_thread_priority_get(k_tid_t thread);
/**
* @brief Set a thread's priority.
*
* This routine immediately changes the priority of @a thread.
*
* Rescheduling can occur immediately depending on the priority @a thread is
* set to:
*
* - If its priority is raised above the priority of the caller of this
* function, and the caller is preemptible, @a thread will be scheduled in.
*
* - If the caller operates on itself, it lowers its priority below that of
* other threads in the system, and the caller is preemptible, the thread of
* highest priority will be scheduled in.
*
* Priority can be assigned in the range of -CONFIG_NUM_COOP_PRIORITIES to
* CONFIG_NUM_PREEMPT_PRIORITIES-1, where -CONFIG_NUM_COOP_PRIORITIES is the
* highest priority.
*
* @param thread ID of thread whose priority is to be set.
* @param prio New priority.
*
* @warning Changing the priority of a thread currently involved in mutex
* priority inheritance may result in undefined behavior.
*
* @return N/A
*/
extern void k_thread_priority_set(k_tid_t thread, int prio);
/**
* @brief Suspend a thread.
*
* This routine prevents the kernel scheduler from making @a thread the
* current thread. All other internal operations on @a thread are still
* performed; for example, any timeout it is waiting on keeps ticking,
* kernel objects it is waiting on are still handed to it, etc.
*
* If @a thread is already suspended, the routine has no effect.
*
* @param thread ID of thread to suspend.
*
* @return N/A
*/
extern void k_thread_suspend(k_tid_t thread);
/**
* @brief Resume a suspended thread.
*
* This routine allows the kernel scheduler to make @a thread the current
* thread, when it is next eligible for that role.
*
* If @a thread is not currently suspended, the routine has no effect.
*
* @param thread ID of thread to resume.
*
* @return N/A
*/
extern void k_thread_resume(k_tid_t thread);
/**
* @brief Set time-slicing period and scope.
*
* This routine specifies how the scheduler will perform time slicing of
* preemptible threads.
*
* To enable time slicing, @a slice must be non-zero. The scheduler
* ensures that no thread runs for more than the specified time limit
* before other threads of that priority are given a chance to execute.
* Any thread whose priority is higher than @a prio is exempted, and may
* execute as long as desired without being preempted due to time slicing.
*
* Time slicing only limits the maximum amount of time a thread may continuously
* execute. Once the scheduler selects a thread for execution, there is no
* minimum guaranteed time the thread will execute before threads of greater or
* equal priority are scheduled.
*
* When the current thread is the only one of that priority eligible
* for execution, this routine has no effect; the thread is immediately
* rescheduled after the slice period expires.
*
* To disable timeslicing, set both @a slice and @a prio to zero.
*
* @param slice Maximum time slice length (in milliseconds).
* @param prio Highest thread priority level eligible for time slicing.
*
* @return N/A
*/
extern void k_sched_time_slice_set(s32_t slice, int prio);
/**
* @} end defgroup thread_apis
*/
/**
* @addtogroup isr_apis
* @{
*/
/**
* @brief Determine if code is running at interrupt level.
*
* This routine allows the caller to customize its actions, depending on
* whether it is a thread or an ISR.
*
* @note Can be called by ISRs.
*
* @return 0 if invoked by a thread.
* @return Non-zero if invoked by an ISR.
*/
extern int k_is_in_isr(void);
/**
* @brief Determine if code is running in a preemptible thread.
*
* This routine allows the caller to customize its actions, depending on
* whether it can be preempted by another thread. The routine returns a 'true'
* value if all of the following conditions are met:
*
* - The code is running in a thread, not at ISR.
* - The thread's priority is in the preemptible range.
* - The thread has not locked the scheduler.
*
* @note Can be called by ISRs.
*
* @return 0 if invoked by an ISR or by a cooperative thread.
* @return Non-zero if invoked by a preemptible thread.
*/
extern int k_is_preempt_thread(void);
/**
* @} end addtogroup isr_apis
*/
/**
* @addtogroup thread_apis
* @{
*/
/**
* @brief Lock the scheduler.
*
* This routine prevents the current thread from being preempted by another
* thread by instructing the scheduler to treat it as a cooperative thread.
* If the thread subsequently performs an operation that makes it unready,
* it will be context switched out in the normal manner. When the thread
* again becomes the current thread, its non-preemptible status is maintained.
*
* This routine can be called recursively.
*
* @note k_sched_lock() and k_sched_unlock() should normally be used
* when the operation being performed can be safely interrupted by ISRs.
* However, if the amount of processing involved is very small, better
* performance may be obtained by using irq_lock() and irq_unlock().
*
* @return N/A
*/
extern void k_sched_lock(void);
/**
* @brief Unlock the scheduler.
*
* This routine reverses the effect of a previous call to k_sched_lock().
* A thread must call the routine once for each time it called k_sched_lock()
* before the thread becomes preemptible.
*
* @return N/A
*/
extern void k_sched_unlock(void);
/**
* @brief Set current thread's custom data.
*
* This routine sets the custom data for the current thread to @ value.
*
* Custom data is not used by the kernel itself, and is freely available
* for a thread to use as it sees fit. It can be used as a framework
* upon which to build thread-local storage.
*
* @param value New custom data value.
*
* @return N/A
*/
extern void k_thread_custom_data_set(void *value);
/**
* @brief Get current thread's custom data.
*
* This routine returns the custom data for the current thread.
*
* @return Current custom data value.
*/
extern void *k_thread_custom_data_get(void);
/**
* @} end addtogroup thread_apis
*/
#include <sys_clock.h>
/**
* @addtogroup clock_apis
* @{
*/
/**
* @brief Generate null timeout delay.
*
* This macro generates a timeout delay that that instructs a kernel API
* not to wait if the requested operation cannot be performed immediately.
*
* @return Timeout delay value.
*/
#define K_NO_WAIT 0
/**
* @brief Generate timeout delay from milliseconds.
*
* This macro generates a timeout delay that that instructs a kernel API
* to wait up to @a ms milliseconds to perform the requested operation.
*
* @param ms Duration in milliseconds.
*
* @return Timeout delay value.
*/
#define K_MSEC(ms) (ms)
/**
* @brief Generate timeout delay from seconds.
*
* This macro generates a timeout delay that that instructs a kernel API
* to wait up to @a s seconds to perform the requested operation.
*
* @param s Duration in seconds.
*
* @return Timeout delay value.
*/
#define K_SECONDS(s) K_MSEC((s) * MSEC_PER_SEC)
/**
* @brief Generate timeout delay from minutes.
*
* This macro generates a timeout delay that that instructs a kernel API
* to wait up to @a m minutes to perform the requested operation.
*
* @param m Duration in minutes.
*
* @return Timeout delay value.
*/
#define K_MINUTES(m) K_SECONDS((m) * 60)
/**
* @brief Generate timeout delay from hours.
*
* This macro generates a timeout delay that that instructs a kernel API
* to wait up to @a h hours to perform the requested operation.
*
* @param h Duration in hours.
*
* @return Timeout delay value.
*/
#define K_HOURS(h) K_MINUTES((h) * 60)
/**
* @brief Generate infinite timeout delay.
*
* This macro generates a timeout delay that that instructs a kernel API
* to wait as long as necessary to perform the requested operation.
*
* @return Timeout delay value.
*/
#define K_FOREVER (-1)
/**
* @} end addtogroup clock_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
/* kernel clocks */
#if (sys_clock_ticks_per_sec == 1000) || \
(sys_clock_ticks_per_sec == 500) || \
(sys_clock_ticks_per_sec == 250) || \
(sys_clock_ticks_per_sec == 125) || \
(sys_clock_ticks_per_sec == 100) || \
(sys_clock_ticks_per_sec == 50) || \
(sys_clock_ticks_per_sec == 25) || \
(sys_clock_ticks_per_sec == 20) || \
(sys_clock_ticks_per_sec == 10) || \
(sys_clock_ticks_per_sec == 1)
#define _ms_per_tick (MSEC_PER_SEC / sys_clock_ticks_per_sec)
#else
/* yields horrible 64-bit math on many architectures: try to avoid */
#define _NON_OPTIMIZED_TICKS_PER_SEC
#endif
#ifdef _NON_OPTIMIZED_TICKS_PER_SEC
extern s32_t _ms_to_ticks(s32_t ms);
#else
static ALWAYS_INLINE s32_t _ms_to_ticks(s32_t ms)
{
return (s32_t)ceiling_fraction((u32_t)ms, _ms_per_tick);
}
#endif
/* added tick needed to account for tick in progress */
#ifdef CONFIG_TICKLESS_KERNEL
#define _TICK_ALIGN 0
#else
#define _TICK_ALIGN 1
#endif
static inline s64_t __ticks_to_ms(s64_t ticks)
{
#ifdef CONFIG_SYS_CLOCK_EXISTS
#ifdef _NON_OPTIMIZED_TICKS_PER_SEC
return (MSEC_PER_SEC * (u64_t)ticks) / sys_clock_ticks_per_sec;
#else
return (u64_t)ticks * _ms_per_tick;
#endif
#else
__ASSERT(ticks == 0, "");
return 0;
#endif
}
struct k_timer {
/*
* _timeout structure must be first here if we want to use
* dynamic timer allocation. timeout.node is used in the double-linked
* list of free timers
*/
struct _timeout timeout;
/* wait queue for the (single) thread waiting on this timer */
_wait_q_t wait_q;
/* runs in ISR context */
void (*expiry_fn)(struct k_timer *);
/* runs in the context of the thread that calls k_timer_stop() */
void (*stop_fn)(struct k_timer *);
/* timer period */
s32_t period;
/* timer status */
u32_t status;
/* user-specific data, also used to support legacy features */
void *user_data;
_OBJECT_TRACING_NEXT_PTR(k_timer);
};
#define _K_TIMER_INITIALIZER(obj, expiry, stop) \
{ \
.timeout.delta_ticks_from_prev = _INACTIVE, \
.timeout.wait_q = NULL, \
.timeout.thread = NULL, \
.timeout.func = _timer_expiration_handler, \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.expiry_fn = expiry, \
.stop_fn = stop, \
.status = 0, \
.user_data = 0, \
_OBJECT_TRACING_INIT \
}
#define K_TIMER_INITIALIZER DEPRECATED_MACRO _K_TIMER_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup timer_apis Timer APIs
* @ingroup kernel_apis
* @{
*/
/**
* @typedef k_timer_expiry_t
* @brief Timer expiry function type.
*
* A timer's expiry function is executed by the system clock interrupt handler
* each time the timer expires. The expiry function is optional, and is only
* invoked if the timer has been initialized with one.
*
* @param timer Address of timer.
*
* @return N/A
*/
typedef void (*k_timer_expiry_t)(struct k_timer *timer);
/**
* @typedef k_timer_stop_t
* @brief Timer stop function type.
*
* A timer's stop function is executed if the timer is stopped prematurely.
* The function runs in the context of the thread that stops the timer.
* The stop function is optional, and is only invoked if the timer has been
* initialized with one.
*
* @param timer Address of timer.
*
* @return N/A
*/
typedef void (*k_timer_stop_t)(struct k_timer *timer);
/**
* @brief Statically define and initialize a timer.
*
* The timer can be accessed outside the module where it is defined using:
*
* @code extern struct k_timer <name>; @endcode
*
* @param name Name of the timer variable.
* @param expiry_fn Function to invoke each time the timer expires.
* @param stop_fn Function to invoke if the timer is stopped while running.
*/
#define K_TIMER_DEFINE(name, expiry_fn, stop_fn) \
struct k_timer name \
__in_section(_k_timer, static, name) = \
_K_TIMER_INITIALIZER(name, expiry_fn, stop_fn)
/**
* @brief Initialize a timer.
*
* This routine initializes a timer, prior to its first use.
*
* @param timer Address of timer.
* @param expiry_fn Function to invoke each time the timer expires.
* @param stop_fn Function to invoke if the timer is stopped while running.
*
* @return N/A
*/
extern void k_timer_init(struct k_timer *timer,
k_timer_expiry_t expiry_fn,
k_timer_stop_t stop_fn);
/**
* @brief Start a timer.
*
* This routine starts a timer, and resets its status to zero. The timer
* begins counting down using the specified duration and period values.
*
* Attempting to start a timer that is already running is permitted.
* The timer's status is reset to zero and the timer begins counting down
* using the new duration and period values.
*
* @param timer Address of timer.
* @param duration Initial timer duration (in milliseconds).
* @param period Timer period (in milliseconds).
*
* @return N/A
*/
extern void k_timer_start(struct k_timer *timer,
s32_t duration, s32_t period);
/**
* @brief Stop a timer.
*
* This routine stops a running timer prematurely. The timer's stop function,
* if one exists, is invoked by the caller.
*
* Attempting to stop a timer that is not running is permitted, but has no
* effect on the timer.
*
* @note Can be called by ISRs. The stop handler has to be callable from ISRs
* if @a k_timer_stop is to be called from ISRs.
*
* @param timer Address of timer.
*
* @return N/A
*/
extern void k_timer_stop(struct k_timer *timer);
/**
* @brief Read timer status.
*
* This routine reads the timer's status, which indicates the number of times
* it has expired since its status was last read.
*
* Calling this routine resets the timer's status to zero.
*
* @param timer Address of timer.
*
* @return Timer status.
*/
extern u32_t k_timer_status_get(struct k_timer *timer);
/**
* @brief Synchronize thread to timer expiration.
*
* This routine blocks the calling thread until the timer's status is non-zero
* (indicating that it has expired at least once since it was last examined)
* or the timer is stopped. If the timer status is already non-zero,
* or the timer is already stopped, the caller continues without waiting.
*
* Calling this routine resets the timer's status to zero.
*
* This routine must not be used by interrupt handlers, since they are not
* allowed to block.
*
* @param timer Address of timer.
*
* @return Timer status.
*/
extern u32_t k_timer_status_sync(struct k_timer *timer);
/**
* @brief Get time remaining before a timer next expires.
*
* This routine computes the (approximate) time remaining before a running
* timer next expires. If the timer is not running, it returns zero.
*
* @param timer Address of timer.
*
* @return Remaining time (in milliseconds).
*/
static inline s32_t k_timer_remaining_get(struct k_timer *timer)
{
return _timeout_remaining_get(&timer->timeout);
}
/**
* @brief Associate user-specific data with a timer.
*
* This routine records the @a user_data with the @a timer, to be retrieved
* later.
*
* It can be used e.g. in a timer handler shared across multiple subsystems to
* retrieve data specific to the subsystem this timer is associated with.
*
* @param timer Address of timer.
* @param user_data User data to associate with the timer.
*
* @return N/A
*/
static inline void k_timer_user_data_set(struct k_timer *timer,
void *user_data)
{
timer->user_data = user_data;
}
/**
* @brief Retrieve the user-specific data from a timer.
*
* @param timer Address of timer.
*
* @return The user data.
*/
static inline void *k_timer_user_data_get(struct k_timer *timer)
{
return timer->user_data;
}
/**
* @} end defgroup timer_apis
*/
/**
* @addtogroup clock_apis
* @{
*/
/**
* @brief Get system uptime.
*
* This routine returns the elapsed time since the system booted,
* in milliseconds.
*
* @return Current uptime.
*/
extern s64_t k_uptime_get(void);
#ifdef CONFIG_TICKLESS_KERNEL
/**
* @brief Enable clock always on in tickless kernel
*
* This routine enables keeping the clock running when
* there are no timer events programmed in tickless kernel
* scheduling. This is necessary if the clock is used to track
* passage of time.
*
* @retval prev_status Previous status of always on flag
*/
static inline int k_enable_sys_clock_always_on(void)
{
int prev_status = _sys_clock_always_on;
_sys_clock_always_on = 1;
_enable_sys_clock();
return prev_status;
}
/**
* @brief Disable clock always on in tickless kernel
*
* This routine disables keeping the clock running when
* there are no timer events programmed in tickless kernel
* scheduling. To save power, this routine should be called
* immediately when clock is not used to track time.
*/
static inline void k_disable_sys_clock_always_on(void)
{
_sys_clock_always_on = 0;
}
#else
#define k_enable_sys_clock_always_on() do { } while ((0))
#define k_disable_sys_clock_always_on() do { } while ((0))
#endif
/**
* @brief Get system uptime (32-bit version).
*
* This routine returns the lower 32-bits of the elapsed time since the system
* booted, in milliseconds.
*
* This routine can be more efficient than k_uptime_get(), as it reduces the
* need for interrupt locking and 64-bit math. However, the 32-bit result
* cannot hold a system uptime time larger than approximately 50 days, so the
* caller must handle possible rollovers.
*
* @return Current uptime.
*/
extern u32_t k_uptime_get_32(void);
/**
* @brief Get elapsed time.
*
* This routine computes the elapsed time between the current system uptime
* and an earlier reference time, in milliseconds.
*
* @param reftime Pointer to a reference time, which is updated to the current
* uptime upon return.
*
* @return Elapsed time.
*/
extern s64_t k_uptime_delta(s64_t *reftime);
/**
* @brief Get elapsed time (32-bit version).
*
* This routine computes the elapsed time between the current system uptime
* and an earlier reference time, in milliseconds.
*
* This routine can be more efficient than k_uptime_delta(), as it reduces the
* need for interrupt locking and 64-bit math. However, the 32-bit result
* cannot hold an elapsed time larger than approximately 50 days, so the
* caller must handle possible rollovers.
*
* @param reftime Pointer to a reference time, which is updated to the current
* uptime upon return.
*
* @return Elapsed time.
*/
extern u32_t k_uptime_delta_32(s64_t *reftime);
/**
* @brief Read the hardware clock.
*
* This routine returns the current time, as measured by the system's hardware
* clock.
*
* @return Current hardware clock up-counter (in cycles).
*/
#define k_cycle_get_32() _arch_k_cycle_get_32()
/**
* @} end addtogroup clock_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_queue {
sys_slist_t data_q;
union {
_wait_q_t wait_q;
_POLL_EVENT;
};
_OBJECT_TRACING_NEXT_PTR(k_queue);
};
#define _K_QUEUE_INITIALIZER(obj) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.data_q = SYS_SLIST_STATIC_INIT(&obj.data_q), \
_POLL_EVENT_OBJ_INIT(obj) \
_OBJECT_TRACING_INIT \
}
#define K_QUEUE_INITIALIZER DEPRECATED_MACRO _K_QUEUE_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup queue_apis Queue APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Initialize a queue.
*
* This routine initializes a queue object, prior to its first use.
*
* @param queue Address of the queue.
*
* @return N/A
*/
extern void k_queue_init(struct k_queue *queue);
/**
* @brief Cancel waiting on a queue.
*
* This routine causes first thread pending on @a queue, if any, to
* return from k_queue_get() call with NULL value (as if timeout expired).
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
*
* @return N/A
*/
extern void k_queue_cancel_wait(struct k_queue *queue);
/**
* @brief Append an element to the end of a queue.
*
* This routine appends a data item to @a queue. A queue data item must be
* aligned on a 4-byte boundary, and the first 32 bits of the item are
* reserved for the kernel's use.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
* @param data Address of the data item.
*
* @return N/A
*/
extern void k_queue_append(struct k_queue *queue, void *data);
/**
* @brief Prepend an element to a queue.
*
* This routine prepends a data item to @a queue. A queue data item must be
* aligned on a 4-byte boundary, and the first 32 bits of the item are
* reserved for the kernel's use.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
* @param data Address of the data item.
*
* @return N/A
*/
extern void k_queue_prepend(struct k_queue *queue, void *data);
/**
* @brief Inserts an element to a queue.
*
* This routine inserts a data item to @a queue after previous item. A queue
* data item must be aligned on a 4-byte boundary, and the first 32 bits of the
* item are reserved for the kernel's use.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
* @param prev Address of the previous data item.
* @param data Address of the data item.
*
* @return N/A
*/
extern void k_queue_insert(struct k_queue *queue, void *prev, void *data);
/**
* @brief Atomically append a list of elements to a queue.
*
* This routine adds a list of data items to @a queue in one operation.
* The data items must be in a singly-linked list, with the first 32 bits
* in each data item pointing to the next data item; the list must be
* NULL-terminated.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
* @param head Pointer to first node in singly-linked list.
* @param tail Pointer to last node in singly-linked list.
*
* @return N/A
*/
extern void k_queue_append_list(struct k_queue *queue, void *head, void *tail);
/**
* @brief Atomically add a list of elements to a queue.
*
* This routine adds a list of data items to @a queue in one operation.
* The data items must be in a singly-linked list implemented using a
* sys_slist_t object. Upon completion, the original list is empty.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
* @param list Pointer to sys_slist_t object.
*
* @return N/A
*/
extern void k_queue_merge_slist(struct k_queue *queue, sys_slist_t *list);
/**
* @brief Get an element from a queue.
*
* This routine removes first data item from @a queue. The first 32 bits of the
* data item are reserved for the kernel's use.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param queue Address of the queue.
* @param timeout Waiting period to obtain a data item (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @return Address of the data item if successful; NULL if returned
* without waiting, or waiting period timed out.
*/
extern void *k_queue_get(struct k_queue *queue, s32_t timeout);
/**
* @brief Remove an element from a queue.
*
* This routine removes data item from @a queue. The first 32 bits of the
* data item are reserved for the kernel's use. Removing elements from k_queue
* rely on sys_slist_find_and_remove which is not a constant time operation.
*
* @note Can be called by ISRs
*
* @param queue Address of the queue.
* @param data Address of the data item.
*
* @return true if data item was removed
*/
static inline bool k_queue_remove(struct k_queue *queue, void *data)
{
return sys_slist_find_and_remove(&queue->data_q, (sys_snode_t *)data);
}
/**
* @brief Query a queue to see if it has data available.
*
* Note that the data might be already gone by the time this function returns
* if other threads are also trying to read from the queue.
*
* @note Can be called by ISRs.
*
* @param queue Address of the queue.
*
* @return Non-zero if the queue is empty.
* @return 0 if data is available.
*/
static inline int k_queue_is_empty(struct k_queue *queue)
{
return (int)sys_slist_is_empty(&queue->data_q);
}
/**
* @brief Peek element at the head of queue.
*
* Return element from the head of queue without removing it.
*
* @param queue Address of the queue.
*
* @return Head element, or NULL if queue is empty.
*/
static inline void *k_queue_peek_head(struct k_queue *queue)
{
return sys_slist_peek_head(&queue->data_q);
}
/**
* @brief Peek element at the tail of queue.
*
* Return element from the tail of queue without removing it.
*
* @param queue Address of the queue.
*
* @return Tail element, or NULL if queue is empty.
*/
static inline void *k_queue_peek_tail(struct k_queue *queue)
{
return sys_slist_peek_tail(&queue->data_q);
}
/**
* @brief Statically define and initialize a queue.
*
* The queue can be accessed outside the module where it is defined using:
*
* @code extern struct k_queue <name>; @endcode
*
* @param name Name of the queue.
*/
#define K_QUEUE_DEFINE(name) \
struct k_queue name \
__in_section(_k_queue, static, name) = \
_K_QUEUE_INITIALIZER(name)
/**
* @} end defgroup queue_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_fifo {
struct k_queue _queue;
};
#define _K_FIFO_INITIALIZER(obj) \
{ \
._queue = _K_QUEUE_INITIALIZER(obj._queue) \
}
#define K_FIFO_INITIALIZER DEPRECATED_MACRO _K_FIFO_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup fifo_apis Fifo APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Initialize a fifo.
*
* This routine initializes a fifo object, prior to its first use.
*
* @param fifo Address of the fifo.
*
* @return N/A
*/
#define k_fifo_init(fifo) \
k_queue_init((struct k_queue *) fifo)
/**
* @brief Cancel waiting on a fifo.
*
* This routine causes first thread pending on @a fifo, if any, to
* return from k_fifo_get() call with NULL value (as if timeout
* expired).
*
* @note Can be called by ISRs.
*
* @param fifo Address of the fifo.
*
* @return N/A
*/
#define k_fifo_cancel_wait(fifo) \
k_queue_cancel_wait((struct k_queue *) fifo)
/**
* @brief Add an element to a fifo.
*
* This routine adds a data item to @a fifo. A fifo data item must be
* aligned on a 4-byte boundary, and the first 32 bits of the item are
* reserved for the kernel's use.
*
* @note Can be called by ISRs.
*
* @param fifo Address of the fifo.
* @param data Address of the data item.
*
* @return N/A
*/
#define k_fifo_put(fifo, data) \
k_queue_append((struct k_queue *) fifo, data)
/**
* @brief Atomically add a list of elements to a fifo.
*
* This routine adds a list of data items to @a fifo in one operation.
* The data items must be in a singly-linked list, with the first 32 bits
* each data item pointing to the next data item; the list must be
* NULL-terminated.
*
* @note Can be called by ISRs.
*
* @param fifo Address of the fifo.
* @param head Pointer to first node in singly-linked list.
* @param tail Pointer to last node in singly-linked list.
*
* @return N/A
*/
#define k_fifo_put_list(fifo, head, tail) \
k_queue_append_list((struct k_queue *) fifo, head, tail)
/**
* @brief Atomically add a list of elements to a fifo.
*
* This routine adds a list of data items to @a fifo in one operation.
* The data items must be in a singly-linked list implemented using a
* sys_slist_t object. Upon completion, the sys_slist_t object is invalid
* and must be re-initialized via sys_slist_init().
*
* @note Can be called by ISRs.
*
* @param fifo Address of the fifo.
* @param list Pointer to sys_slist_t object.
*
* @return N/A
*/
#define k_fifo_put_slist(fifo, list) \
k_queue_merge_slist((struct k_queue *) fifo, list)
/**
* @brief Get an element from a fifo.
*
* This routine removes a data item from @a fifo in a "first in, first out"
* manner. The first 32 bits of the data item are reserved for the kernel's use.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param fifo Address of the fifo.
* @param timeout Waiting period to obtain a data item (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @return Address of the data item if successful; NULL if returned
* without waiting, or waiting period timed out.
*/
#define k_fifo_get(fifo, timeout) \
k_queue_get((struct k_queue *) fifo, timeout)
/**
* @brief Query a fifo to see if it has data available.
*
* Note that the data might be already gone by the time this function returns
* if other threads is also trying to read from the fifo.
*
* @note Can be called by ISRs.
*
* @param fifo Address of the fifo.
*
* @return Non-zero if the fifo is empty.
* @return 0 if data is available.
*/
#define k_fifo_is_empty(fifo) \
k_queue_is_empty((struct k_queue *) fifo)
/**
* @brief Peek element at the head of fifo.
*
* Return element from the head of fifo without removing it. A usecase
* for this is if elements of the fifo are themselves containers. Then
* on each iteration of processing, a head container will be peeked,
* and some data processed out of it, and only if the container is empty,
* it will be completely remove from the fifo.
*
* @param fifo Address of the fifo.
*
* @return Head element, or NULL if the fifo is empty.
*/
#define k_fifo_peek_head(fifo) \
k_queue_peek_head((struct k_queue *) fifo)
/**
* @brief Peek element at the tail of fifo.
*
* Return element from the tail of fifo (without removing it). A usecase
* for this is if elements of the fifo are themselves containers. Then
* it may be useful to add more data to the last container in fifo.
*
* @param fifo Address of the fifo.
*
* @return Tail element, or NULL if fifo is empty.
*/
#define k_fifo_peek_tail(fifo) \
k_queue_peek_tail((struct k_queue *) fifo)
/**
* @brief Statically define and initialize a fifo.
*
* The fifo can be accessed outside the module where it is defined using:
*
* @code extern struct k_fifo <name>; @endcode
*
* @param name Name of the fifo.
*/
#define K_FIFO_DEFINE(name) \
struct k_fifo name \
__in_section(_k_queue, static, name) = \
_K_FIFO_INITIALIZER(name)
/**
* @} end defgroup fifo_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_lifo {
struct k_queue _queue;
};
#define _K_LIFO_INITIALIZER(obj) \
{ \
._queue = _K_QUEUE_INITIALIZER(obj._queue) \
}
#define K_LIFO_INITIALIZER DEPRECATED_MACRO _K_LIFO_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup lifo_apis Lifo APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Initialize a lifo.
*
* This routine initializes a lifo object, prior to its first use.
*
* @param lifo Address of the lifo.
*
* @return N/A
*/
#define k_lifo_init(lifo) \
k_queue_init((struct k_queue *) lifo)
/**
* @brief Add an element to a lifo.
*
* This routine adds a data item to @a lifo. A lifo data item must be
* aligned on a 4-byte boundary, and the first 32 bits of the item are
* reserved for the kernel's use.
*
* @note Can be called by ISRs.
*
* @param lifo Address of the lifo.
* @param data Address of the data item.
*
* @return N/A
*/
#define k_lifo_put(lifo, data) \
k_queue_prepend((struct k_queue *) lifo, data)
/**
* @brief Get an element from a lifo.
*
* This routine removes a data item from @a lifo in a "last in, first out"
* manner. The first 32 bits of the data item are reserved for the kernel's use.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param lifo Address of the lifo.
* @param timeout Waiting period to obtain a data item (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @return Address of the data item if successful; NULL if returned
* without waiting, or waiting period timed out.
*/
#define k_lifo_get(lifo, timeout) \
k_queue_get((struct k_queue *) lifo, timeout)
/**
* @brief Statically define and initialize a lifo.
*
* The lifo can be accessed outside the module where it is defined using:
*
* @code extern struct k_lifo <name>; @endcode
*
* @param name Name of the fifo.
*/
#define K_LIFO_DEFINE(name) \
struct k_lifo name \
__in_section(_k_queue, static, name) = \
_K_LIFO_INITIALIZER(name)
/**
* @} end defgroup lifo_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_stack {
_wait_q_t wait_q;
u32_t *base, *next, *top;
_OBJECT_TRACING_NEXT_PTR(k_stack);
};
#define _K_STACK_INITIALIZER(obj, stack_buffer, stack_num_entries) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.base = stack_buffer, \
.next = stack_buffer, \
.top = stack_buffer + stack_num_entries, \
_OBJECT_TRACING_INIT \
}
#define K_STACK_INITIALIZER DEPRECATED_MACRO _K_STACK_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup stack_apis Stack APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Initialize a stack.
*
* This routine initializes a stack object, prior to its first use.
*
* @param stack Address of the stack.
* @param buffer Address of array used to hold stacked values.
* @param num_entries Maximum number of values that can be stacked.
*
* @return N/A
*/
extern void k_stack_init(struct k_stack *stack,
u32_t *buffer, int num_entries);
/**
* @brief Push an element onto a stack.
*
* This routine adds a 32-bit value @a data to @a stack.
*
* @note Can be called by ISRs.
*
* @param stack Address of the stack.
* @param data Value to push onto the stack.
*
* @return N/A
*/
extern void k_stack_push(struct k_stack *stack, u32_t data);
/**
* @brief Pop an element from a stack.
*
* This routine removes a 32-bit value from @a stack in a "last in, first out"
* manner and stores the value in @a data.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param stack Address of the stack.
* @param data Address of area to hold the value popped from the stack.
* @param timeout Waiting period to obtain a value (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 Element popped from stack.
* @retval -EBUSY Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_stack_pop(struct k_stack *stack, u32_t *data, s32_t timeout);
/**
* @brief Statically define and initialize a stack
*
* The stack can be accessed outside the module where it is defined using:
*
* @code extern struct k_stack <name>; @endcode
*
* @param name Name of the stack.
* @param stack_num_entries Maximum number of values that can be stacked.
*/
#define K_STACK_DEFINE(name, stack_num_entries) \
u32_t __noinit \
_k_stack_buf_##name[stack_num_entries]; \
struct k_stack name \
__in_section(_k_stack, static, name) = \
_K_STACK_INITIALIZER(name, _k_stack_buf_##name, \
stack_num_entries)
/**
* @} end defgroup stack_apis
*/
struct k_work;
/**
* @defgroup workqueue_apis Workqueue Thread APIs
* @ingroup kernel_apis
* @{
*/
/**
* @typedef k_work_handler_t
* @brief Work item handler function type.
*
* A work item's handler function is executed by a workqueue's thread
* when the work item is processed by the workqueue.
*
* @param work Address of the work item.
*
* @return N/A
*/
typedef void (*k_work_handler_t)(struct k_work *work);
/**
* @cond INTERNAL_HIDDEN
*/
struct k_work_q {
struct k_queue queue;
struct k_thread thread;
};
enum {
K_WORK_STATE_PENDING, /* Work item pending state */
};
struct k_work {
void *_reserved; /* Used by k_queue implementation. */
k_work_handler_t handler;
atomic_t flags[1];
};
struct k_delayed_work {
struct k_work work;
struct _timeout timeout;
struct k_work_q *work_q;
};
extern struct k_work_q k_sys_work_q;
/**
* INTERNAL_HIDDEN @endcond
*/
#define _K_WORK_INITIALIZER(work_handler) \
{ \
._reserved = NULL, \
.handler = work_handler, \
.flags = { 0 } \
}
#define K_WORK_INITIALIZER DEPRECATED_MACRO _K_WORK_INITIALIZER
/**
* @brief Initialize a statically-defined work item.
*
* This macro can be used to initialize a statically-defined workqueue work
* item, prior to its first use. For example,
*
* @code static K_WORK_DEFINE(<work>, <work_handler>); @endcode
*
* @param work Symbol name for work item object
* @param work_handler Function to invoke each time work item is processed.
*/
#define K_WORK_DEFINE(work, work_handler) \
struct k_work work \
__in_section(_k_work, static, work) = \
_K_WORK_INITIALIZER(work_handler)
/**
* @brief Initialize a work item.
*
* This routine initializes a workqueue work item, prior to its first use.
*
* @param work Address of work item.
* @param handler Function to invoke each time work item is processed.
*
* @return N/A
*/
static inline void k_work_init(struct k_work *work, k_work_handler_t handler)
{
atomic_clear_bit(work->flags, K_WORK_STATE_PENDING);
work->handler = handler;
}
/**
* @brief Submit a work item.
*
* This routine submits work item @a work to be processed by workqueue
* @a work_q. If the work item is already pending in the workqueue's queue
* as a result of an earlier submission, this routine has no effect on the
* work item. If the work item has already been processed, or is currently
* being processed, its work is considered complete and the work item can be
* resubmitted.
*
* @warning
* A submitted work item must not be modified until it has been processed
* by the workqueue.
*
* @note Can be called by ISRs.
*
* @param work_q Address of workqueue.
* @param work Address of work item.
*
* @return N/A
*/
static inline void k_work_submit_to_queue(struct k_work_q *work_q,
struct k_work *work)
{
if (!atomic_test_and_set_bit(work->flags, K_WORK_STATE_PENDING)) {
k_queue_append(&work_q->queue, work);
}
}
/**
* @brief Check if a work item is pending.
*
* This routine indicates if work item @a work is pending in a workqueue's
* queue.
*
* @note Can be called by ISRs.
*
* @param work Address of work item.
*
* @return 1 if work item is pending, or 0 if it is not pending.
*/
static inline int k_work_pending(struct k_work *work)
{
return atomic_test_bit(work->flags, K_WORK_STATE_PENDING);
}
/**
* @brief Start a workqueue.
*
* This routine starts workqueue @a work_q. The workqueue spawns its work
* processing thread, which runs forever.
*
* @param work_q Address of workqueue.
* @param stack Pointer to work queue thread's stack space, as defined by
* K_THREAD_STACK_DEFINE()
* @param stack_size Size of the work queue thread's stack (in bytes), which
* should either be the same constant passed to
* K_THREAD_STACK_DEFINE() or the value of K_THREAD_STACK_SIZEOF().
* @param prio Priority of the work queue's thread.
*
* @return N/A
*/
extern void k_work_q_start(struct k_work_q *work_q,
k_thread_stack_t stack,
size_t stack_size, int prio);
/**
* @brief Initialize a delayed work item.
*
* This routine initializes a workqueue delayed work item, prior to
* its first use.
*
* @param work Address of delayed work item.
* @param handler Function to invoke each time work item is processed.
*
* @return N/A
*/
extern void k_delayed_work_init(struct k_delayed_work *work,
k_work_handler_t handler);
/**
* @brief Submit a delayed work item.
*
* This routine schedules work item @a work to be processed by workqueue
* @a work_q after a delay of @a delay milliseconds. The routine initiates
* an asynchronous countdown for the work item and then returns to the caller.
* Only when the countdown completes is the work item actually submitted to
* the workqueue and becomes pending.
*
* Submitting a previously submitted delayed work item that is still
* counting down cancels the existing submission and restarts the countdown
* using the new delay. If the work item is currently pending on the
* workqueue's queue because the countdown has completed it is too late to
* resubmit the item, and resubmission fails without impacting the work item.
* If the work item has already been processed, or is currently being processed,
* its work is considered complete and the work item can be resubmitted.
*
* @warning
* A delayed work item must not be modified until it has been processed
* by the workqueue.
*
* @note Can be called by ISRs.
*
* @param work_q Address of workqueue.
* @param work Address of delayed work item.
* @param delay Delay before submitting the work item (in milliseconds).
*
* @retval 0 Work item countdown started.
* @retval -EINPROGRESS Work item is already pending.
* @retval -EINVAL Work item is being processed or has completed its work.
* @retval -EADDRINUSE Work item is pending on a different workqueue.
*/
extern int k_delayed_work_submit_to_queue(struct k_work_q *work_q,
struct k_delayed_work *work,
s32_t delay);
/**
* @brief Cancel a delayed work item.
*
* This routine cancels the submission of delayed work item @a work.
* A delayed work item can only be canceled while its countdown is still
* underway.
*
* @note Can be called by ISRs.
*
* @param work Address of delayed work item.
*
* @retval 0 Work item countdown canceled.
* @retval -EINPROGRESS Work item is already pending.
* @retval -EINVAL Work item is being processed or has completed its work.
*/
extern int k_delayed_work_cancel(struct k_delayed_work *work);
/**
* @brief Submit a work item to the system workqueue.
*
* This routine submits work item @a work to be processed by the system
* workqueue. If the work item is already pending in the workqueue's queue
* as a result of an earlier submission, this routine has no effect on the
* work item. If the work item has already been processed, or is currently
* being processed, its work is considered complete and the work item can be
* resubmitted.
*
* @warning
* Work items submitted to the system workqueue should avoid using handlers
* that block or yield since this may prevent the system workqueue from
* processing other work items in a timely manner.
*
* @note Can be called by ISRs.
*
* @param work Address of work item.
*
* @return N/A
*/
static inline void k_work_submit(struct k_work *work)
{
k_work_submit_to_queue(&k_sys_work_q, work);
}
/**
* @brief Submit a delayed work item to the system workqueue.
*
* This routine schedules work item @a work to be processed by the system
* workqueue after a delay of @a delay milliseconds. The routine initiates
* an asynchronous countdown for the work item and then returns to the caller.
* Only when the countdown completes is the work item actually submitted to
* the workqueue and becomes pending.
*
* Submitting a previously submitted delayed work item that is still
* counting down cancels the existing submission and restarts the countdown
* using the new delay. If the work item is currently pending on the
* workqueue's queue because the countdown has completed it is too late to
* resubmit the item, and resubmission fails without impacting the work item.
* If the work item has already been processed, or is currently being processed,
* its work is considered complete and the work item can be resubmitted.
*
* @warning
* Work items submitted to the system workqueue should avoid using handlers
* that block or yield since this may prevent the system workqueue from
* processing other work items in a timely manner.
*
* @note Can be called by ISRs.
*
* @param work Address of delayed work item.
* @param delay Delay before submitting the work item (in milliseconds).
*
* @retval 0 Work item countdown started.
* @retval -EINPROGRESS Work item is already pending.
* @retval -EINVAL Work item is being processed or has completed its work.
* @retval -EADDRINUSE Work item is pending on a different workqueue.
*/
static inline int k_delayed_work_submit(struct k_delayed_work *work,
s32_t delay)
{
return k_delayed_work_submit_to_queue(&k_sys_work_q, work, delay);
}
/**
* @brief Get time remaining before a delayed work gets scheduled.
*
* This routine computes the (approximate) time remaining before a
* delayed work gets executed. If the delayed work is not waiting to be
* schedules, it returns zero.
*
* @param work Delayed work item.
*
* @return Remaining time (in milliseconds).
*/
static inline s32_t k_delayed_work_remaining_get(struct k_delayed_work *work)
{
return _timeout_remaining_get(&work->timeout);
}
/**
* @} end defgroup workqueue_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_mutex {
_wait_q_t wait_q;
struct k_thread *owner;
u32_t lock_count;
int owner_orig_prio;
_OBJECT_TRACING_NEXT_PTR(k_mutex);
};
#define _K_MUTEX_INITIALIZER(obj) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.owner = NULL, \
.lock_count = 0, \
.owner_orig_prio = K_LOWEST_THREAD_PRIO, \
_OBJECT_TRACING_INIT \
}
#define K_MUTEX_INITIALIZER DEPRECATED_MACRO _K_MUTEX_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup mutex_apis Mutex APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Statically define and initialize a mutex.
*
* The mutex can be accessed outside the module where it is defined using:
*
* @code extern struct k_mutex <name>; @endcode
*
* @param name Name of the mutex.
*/
#define K_MUTEX_DEFINE(name) \
struct k_mutex name \
__in_section(_k_mutex, static, name) = \
_K_MUTEX_INITIALIZER(name)
/**
* @brief Initialize a mutex.
*
* This routine initializes a mutex object, prior to its first use.
*
* Upon completion, the mutex is available and does not have an owner.
*
* @param mutex Address of the mutex.
*
* @return N/A
*/
extern void k_mutex_init(struct k_mutex *mutex);
/**
* @brief Lock a mutex.
*
* This routine locks @a mutex. If the mutex is locked by another thread,
* the calling thread waits until the mutex becomes available or until
* a timeout occurs.
*
* A thread is permitted to lock a mutex it has already locked. The operation
* completes immediately and the lock count is increased by 1.
*
* @param mutex Address of the mutex.
* @param timeout Waiting period to lock the mutex (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 Mutex locked.
* @retval -EBUSY Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mutex_lock(struct k_mutex *mutex, s32_t timeout);
/**
* @brief Unlock a mutex.
*
* This routine unlocks @a mutex. The mutex must already be locked by the
* calling thread.
*
* The mutex cannot be claimed by another thread until it has been unlocked by
* the calling thread as many times as it was previously locked by that
* thread.
*
* @param mutex Address of the mutex.
*
* @return N/A
*/
extern void k_mutex_unlock(struct k_mutex *mutex);
/**
* @} end defgroup mutex_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_sem {
_wait_q_t wait_q;
unsigned int count;
unsigned int limit;
_POLL_EVENT;
_OBJECT_TRACING_NEXT_PTR(k_sem);
};
#define _K_SEM_INITIALIZER(obj, initial_count, count_limit) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.count = initial_count, \
.limit = count_limit, \
_POLL_EVENT_OBJ_INIT(obj) \
_OBJECT_TRACING_INIT \
}
#define K_SEM_INITIALIZER DEPRECATED_MACRO _K_SEM_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup semaphore_apis Semaphore APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Initialize a semaphore.
*
* This routine initializes a semaphore object, prior to its first use.
*
* @param sem Address of the semaphore.
* @param initial_count Initial semaphore count.
* @param limit Maximum permitted semaphore count.
*
* @return N/A
*/
extern void k_sem_init(struct k_sem *sem, unsigned int initial_count,
unsigned int limit);
/**
* @brief Take a semaphore.
*
* This routine takes @a sem.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param sem Address of the semaphore.
* @param timeout Waiting period to take the semaphore (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @note When porting code from the nanokernel legacy API to the new API, be
* careful with the return value of this function. The return value is the
* reverse of the one of nano_sem_take family of APIs: 0 means success, and
* non-zero means failure, while the nano_sem_take family returns 1 for success
* and 0 for failure.
*
* @retval 0 Semaphore taken.
* @retval -EBUSY Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_sem_take(struct k_sem *sem, s32_t timeout);
/**
* @brief Give a semaphore.
*
* This routine gives @a sem, unless the semaphore is already at its maximum
* permitted count.
*
* @note Can be called by ISRs.
*
* @param sem Address of the semaphore.
*
* @return N/A
*/
extern void k_sem_give(struct k_sem *sem);
/**
* @brief Reset a semaphore's count to zero.
*
* This routine sets the count of @a sem to zero.
*
* @param sem Address of the semaphore.
*
* @return N/A
*/
static inline void k_sem_reset(struct k_sem *sem)
{
sem->count = 0;
}
/**
* @brief Get a semaphore's count.
*
* This routine returns the current count of @a sem.
*
* @param sem Address of the semaphore.
*
* @return Current semaphore count.
*/
static inline unsigned int k_sem_count_get(struct k_sem *sem)
{
return sem->count;
}
/**
* @brief Statically define and initialize a semaphore.
*
* The semaphore can be accessed outside the module where it is defined using:
*
* @code extern struct k_sem <name>; @endcode
*
* @param name Name of the semaphore.
* @param initial_count Initial semaphore count.
* @param count_limit Maximum permitted semaphore count.
*/
#define K_SEM_DEFINE(name, initial_count, count_limit) \
struct k_sem name \
__in_section(_k_sem, static, name) = \
_K_SEM_INITIALIZER(name, initial_count, count_limit)
/**
* @} end defgroup semaphore_apis
*/
/**
* @defgroup alert_apis Alert APIs
* @ingroup kernel_apis
* @{
*/
/**
* @typedef k_alert_handler_t
* @brief Alert handler function type.
*
* An alert's alert handler function is invoked by the system workqueue
* when the alert is signaled. The alert handler function is optional,
* and is only invoked if the alert has been initialized with one.
*
* @param alert Address of the alert.
*
* @return 0 if alert has been consumed; non-zero if alert should pend.
*/
typedef int (*k_alert_handler_t)(struct k_alert *alert);
/**
* @} end defgroup alert_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
#define K_ALERT_DEFAULT NULL
#define K_ALERT_IGNORE ((void *)(-1))
struct k_alert {
k_alert_handler_t handler;
atomic_t send_count;
struct k_work work_item;
struct k_sem sem;
_OBJECT_TRACING_NEXT_PTR(k_alert);
};
extern void _alert_deliver(struct k_work *work);
#define _K_ALERT_INITIALIZER(obj, alert_handler, max_num_pending_alerts) \
{ \
.handler = (k_alert_handler_t)alert_handler, \
.send_count = ATOMIC_INIT(0), \
.work_item = _K_WORK_INITIALIZER(_alert_deliver), \
.sem = _K_SEM_INITIALIZER(obj.sem, 0, max_num_pending_alerts), \
_OBJECT_TRACING_INIT \
}
#define K_ALERT_INITIALIZER DEPRECATED_MACRO _K_ALERT_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @addtogroup alert_apis
* @{
*/
/**
* @brief Statically define and initialize an alert.
*
* The alert can be accessed outside the module where it is defined using:
*
* @code extern struct k_alert <name>; @endcode
*
* @param name Name of the alert.
* @param alert_handler Action to take when alert is sent. Specify either
* the address of a function to be invoked by the system workqueue
* thread, K_ALERT_IGNORE (which causes the alert to be ignored), or
* K_ALERT_DEFAULT (which causes the alert to pend).
* @param max_num_pending_alerts Maximum number of pending alerts.
*/
#define K_ALERT_DEFINE(name, alert_handler, max_num_pending_alerts) \
struct k_alert name \
__in_section(_k_alert, static, name) = \
_K_ALERT_INITIALIZER(name, alert_handler, \
max_num_pending_alerts)
/**
* @brief Initialize an alert.
*
* This routine initializes an alert object, prior to its first use.
*
* @param alert Address of the alert.
* @param handler Action to take when alert is sent. Specify either the address
* of a function to be invoked by the system workqueue thread,
* K_ALERT_IGNORE (which causes the alert to be ignored), or
* K_ALERT_DEFAULT (which causes the alert to pend).
* @param max_num_pending_alerts Maximum number of pending alerts.
*
* @return N/A
*/
extern void k_alert_init(struct k_alert *alert, k_alert_handler_t handler,
unsigned int max_num_pending_alerts);
/**
* @brief Receive an alert.
*
* This routine receives a pending alert for @a alert.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param alert Address of the alert.
* @param timeout Waiting period to receive the alert (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 Alert received.
* @retval -EBUSY Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_alert_recv(struct k_alert *alert, s32_t timeout);
/**
* @brief Signal an alert.
*
* This routine signals @a alert. The action specified for @a alert will
* be taken, which may trigger the execution of an alert handler function
* and/or cause the alert to pend (assuming the alert has not reached its
* maximum number of pending alerts).
*
* @note Can be called by ISRs.
*
* @param alert Address of the alert.
*
* @return N/A
*/
extern void k_alert_send(struct k_alert *alert);
/**
* @} end addtogroup alert_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_msgq {
_wait_q_t wait_q;
size_t msg_size;
u32_t max_msgs;
char *buffer_start;
char *buffer_end;
char *read_ptr;
char *write_ptr;
u32_t used_msgs;
_OBJECT_TRACING_NEXT_PTR(k_msgq);
};
#define _K_MSGQ_INITIALIZER(obj, q_buffer, q_msg_size, q_max_msgs) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.max_msgs = q_max_msgs, \
.msg_size = q_msg_size, \
.buffer_start = q_buffer, \
.buffer_end = q_buffer + (q_max_msgs * q_msg_size), \
.read_ptr = q_buffer, \
.write_ptr = q_buffer, \
.used_msgs = 0, \
_OBJECT_TRACING_INIT \
}
#define K_MSGQ_INITIALIZER DEPRECATED_MACRO _K_MSGQ_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup msgq_apis Message Queue APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Statically define and initialize a message queue.
*
* The message queue's ring buffer contains space for @a q_max_msgs messages,
* each of which is @a q_msg_size bytes long. The buffer is aligned to a
* @a q_align -byte boundary, which must be a power of 2. To ensure that each
* message is similarly aligned to this boundary, @a q_msg_size must also be
* a multiple of @a q_align.
*
* The message queue can be accessed outside the module where it is defined
* using:
*
* @code extern struct k_msgq <name>; @endcode
*
* @param q_name Name of the message queue.
* @param q_msg_size Message size (in bytes).
* @param q_max_msgs Maximum number of messages that can be queued.
* @param q_align Alignment of the message queue's ring buffer.
*/
#define K_MSGQ_DEFINE(q_name, q_msg_size, q_max_msgs, q_align) \
static char __noinit __aligned(q_align) \
_k_fifo_buf_##q_name[(q_max_msgs) * (q_msg_size)]; \
struct k_msgq q_name \
__in_section(_k_msgq, static, q_name) = \
_K_MSGQ_INITIALIZER(q_name, _k_fifo_buf_##q_name, \
q_msg_size, q_max_msgs)
/**
* @brief Initialize a message queue.
*
* This routine initializes a message queue object, prior to its first use.
*
* The message queue's ring buffer must contain space for @a max_msgs messages,
* each of which is @a msg_size bytes long. The buffer must be aligned to an
* N-byte boundary, where N is a power of 2 (i.e. 1, 2, 4, ...). To ensure
* that each message is similarly aligned to this boundary, @a q_msg_size
* must also be a multiple of N.
*
* @param q Address of the message queue.
* @param buffer Pointer to ring buffer that holds queued messages.
* @param msg_size Message size (in bytes).
* @param max_msgs Maximum number of messages that can be queued.
*
* @return N/A
*/
extern void k_msgq_init(struct k_msgq *q, char *buffer,
size_t msg_size, u32_t max_msgs);
/**
* @brief Send a message to a message queue.
*
* This routine sends a message to message queue @a q.
*
* @note Can be called by ISRs.
*
* @param q Address of the message queue.
* @param data Pointer to the message.
* @param timeout Waiting period to add the message (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 Message sent.
* @retval -ENOMSG Returned without waiting or queue purged.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_msgq_put(struct k_msgq *q, void *data, s32_t timeout);
/**
* @brief Receive a message from a message queue.
*
* This routine receives a message from message queue @a q in a "first in,
* first out" manner.
*
* @note Can be called by ISRs, but @a timeout must be set to K_NO_WAIT.
*
* @param q Address of the message queue.
* @param data Address of area to hold the received message.
* @param timeout Waiting period to receive the message (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 Message received.
* @retval -ENOMSG Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_msgq_get(struct k_msgq *q, void *data, s32_t timeout);
/**
* @brief Purge a message queue.
*
* This routine discards all unreceived messages in a message queue's ring
* buffer. Any threads that are blocked waiting to send a message to the
* message queue are unblocked and see an -ENOMSG error code.
*
* @param q Address of the message queue.
*
* @return N/A
*/
extern void k_msgq_purge(struct k_msgq *q);
/**
* @brief Get the amount of free space in a message queue.
*
* This routine returns the number of unused entries in a message queue's
* ring buffer.
*
* @param q Address of the message queue.
*
* @return Number of unused ring buffer entries.
*/
static inline u32_t k_msgq_num_free_get(struct k_msgq *q)
{
return q->max_msgs - q->used_msgs;
}
/**
* @brief Get the number of messages in a message queue.
*
* This routine returns the number of messages in a message queue's ring buffer.
*
* @param q Address of the message queue.
*
* @return Number of messages.
*/
static inline u32_t k_msgq_num_used_get(struct k_msgq *q)
{
return q->used_msgs;
}
/**
* @} end defgroup msgq_apis
*/
/**
* @defgroup mem_pool_apis Memory Pool APIs
* @ingroup kernel_apis
* @{
*/
/* Note on sizing: the use of a 20 bit field for block means that,
* assuming a reasonable minimum block size of 16 bytes, we're limited
* to 16M of memory managed by a single pool. Long term it would be
* good to move to a variable bit size based on configuration.
*/
struct k_mem_block_id {
u32_t pool : 8;
u32_t level : 4;
u32_t block : 20;
};
struct k_mem_block {
void *data;
struct k_mem_block_id id;
};
/**
* @} end defgroup mem_pool_apis
*/
/**
* @defgroup mailbox_apis Mailbox APIs
* @ingroup kernel_apis
* @{
*/
struct k_mbox_msg {
/** internal use only - needed for legacy API support */
u32_t _mailbox;
/** size of message (in bytes) */
size_t size;
/** application-defined information value */
u32_t info;
/** sender's message data buffer */
void *tx_data;
/** internal use only - needed for legacy API support */
void *_rx_data;
/** message data block descriptor */
struct k_mem_block tx_block;
/** source thread id */
k_tid_t rx_source_thread;
/** target thread id */
k_tid_t tx_target_thread;
/** internal use only - thread waiting on send (may be a dummy) */
k_tid_t _syncing_thread;
#if (CONFIG_NUM_MBOX_ASYNC_MSGS > 0)
/** internal use only - semaphore used during asynchronous send */
struct k_sem *_async_sem;
#endif
};
/**
* @cond INTERNAL_HIDDEN
*/
struct k_mbox {
_wait_q_t tx_msg_queue;
_wait_q_t rx_msg_queue;
_OBJECT_TRACING_NEXT_PTR(k_mbox);
};
#define _K_MBOX_INITIALIZER(obj) \
{ \
.tx_msg_queue = SYS_DLIST_STATIC_INIT(&obj.tx_msg_queue), \
.rx_msg_queue = SYS_DLIST_STATIC_INIT(&obj.rx_msg_queue), \
_OBJECT_TRACING_INIT \
}
#define K_MBOX_INITIALIZER DEPRECATED_MACRO _K_MBOX_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @brief Statically define and initialize a mailbox.
*
* The mailbox is to be accessed outside the module where it is defined using:
*
* @code extern struct k_mbox <name>; @endcode
*
* @param name Name of the mailbox.
*/
#define K_MBOX_DEFINE(name) \
struct k_mbox name \
__in_section(_k_mbox, static, name) = \
_K_MBOX_INITIALIZER(name) \
/**
* @brief Initialize a mailbox.
*
* This routine initializes a mailbox object, prior to its first use.
*
* @param mbox Address of the mailbox.
*
* @return N/A
*/
extern void k_mbox_init(struct k_mbox *mbox);
/**
* @brief Send a mailbox message in a synchronous manner.
*
* This routine sends a message to @a mbox and waits for a receiver to both
* receive and process it. The message data may be in a buffer, in a memory
* pool block, or non-existent (i.e. an empty message).
*
* @param mbox Address of the mailbox.
* @param tx_msg Address of the transmit message descriptor.
* @param timeout Waiting period for the message to be received (in
* milliseconds), or one of the special values K_NO_WAIT
* and K_FOREVER. Once the message has been received,
* this routine waits as long as necessary for the message
* to be completely processed.
*
* @retval 0 Message sent.
* @retval -ENOMSG Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mbox_put(struct k_mbox *mbox, struct k_mbox_msg *tx_msg,
s32_t timeout);
/**
* @brief Send a mailbox message in an asynchronous manner.
*
* This routine sends a message to @a mbox without waiting for a receiver
* to process it. The message data may be in a buffer, in a memory pool block,
* or non-existent (i.e. an empty message). Optionally, the semaphore @a sem
* will be given when the message has been both received and completely
* processed by the receiver.
*
* @param mbox Address of the mailbox.
* @param tx_msg Address of the transmit message descriptor.
* @param sem Address of a semaphore, or NULL if none is needed.
*
* @return N/A
*/
extern void k_mbox_async_put(struct k_mbox *mbox, struct k_mbox_msg *tx_msg,
struct k_sem *sem);
/**
* @brief Receive a mailbox message.
*
* This routine receives a message from @a mbox, then optionally retrieves
* its data and disposes of the message.
*
* @param mbox Address of the mailbox.
* @param rx_msg Address of the receive message descriptor.
* @param buffer Address of the buffer to receive data, or NULL to defer data
* retrieval and message disposal until later.
* @param timeout Waiting period for a message to be received (in
* milliseconds), or one of the special values K_NO_WAIT
* and K_FOREVER.
*
* @retval 0 Message received.
* @retval -ENOMSG Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mbox_get(struct k_mbox *mbox, struct k_mbox_msg *rx_msg,
void *buffer, s32_t timeout);
/**
* @brief Retrieve mailbox message data into a buffer.
*
* This routine completes the processing of a received message by retrieving
* its data into a buffer, then disposing of the message.
*
* Alternatively, this routine can be used to dispose of a received message
* without retrieving its data.
*
* @param rx_msg Address of the receive message descriptor.
* @param buffer Address of the buffer to receive data, or NULL to discard
* the data.
*
* @return N/A
*/
extern void k_mbox_data_get(struct k_mbox_msg *rx_msg, void *buffer);
/**
* @brief Retrieve mailbox message data into a memory pool block.
*
* This routine completes the processing of a received message by retrieving
* its data into a memory pool block, then disposing of the message.
* The memory pool block that results from successful retrieval must be
* returned to the pool once the data has been processed, even in cases
* where zero bytes of data are retrieved.
*
* Alternatively, this routine can be used to dispose of a received message
* without retrieving its data. In this case there is no need to return a
* memory pool block to the pool.
*
* This routine allocates a new memory pool block for the data only if the
* data is not already in one. If a new block cannot be allocated, the routine
* returns a failure code and the received message is left unchanged. This
* permits the caller to reattempt data retrieval at a later time or to dispose
* of the received message without retrieving its data.
*
* @param rx_msg Address of a receive message descriptor.
* @param pool Address of memory pool, or NULL to discard data.
* @param block Address of the area to hold memory pool block info.
* @param timeout Waiting period to wait for a memory pool block (in
* milliseconds), or one of the special values K_NO_WAIT
* and K_FOREVER.
*
* @retval 0 Data retrieved.
* @retval -ENOMEM Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mbox_data_block_get(struct k_mbox_msg *rx_msg,
struct k_mem_pool *pool,
struct k_mem_block *block, s32_t timeout);
/**
* @} end defgroup mailbox_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_pipe {
unsigned char *buffer; /* Pipe buffer: may be NULL */
size_t size; /* Buffer size */
size_t bytes_used; /* # bytes used in buffer */
size_t read_index; /* Where in buffer to read from */
size_t write_index; /* Where in buffer to write */
struct {
_wait_q_t readers; /* Reader wait queue */
_wait_q_t writers; /* Writer wait queue */
} wait_q;
_OBJECT_TRACING_NEXT_PTR(k_pipe);
};
#define _K_PIPE_INITIALIZER(obj, pipe_buffer, pipe_buffer_size) \
{ \
.buffer = pipe_buffer, \
.size = pipe_buffer_size, \
.bytes_used = 0, \
.read_index = 0, \
.write_index = 0, \
.wait_q.writers = SYS_DLIST_STATIC_INIT(&obj.wait_q.writers), \
.wait_q.readers = SYS_DLIST_STATIC_INIT(&obj.wait_q.readers), \
_OBJECT_TRACING_INIT \
}
#define K_PIPE_INITIALIZER DEPRECATED_MACRO _K_PIPE_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup pipe_apis Pipe APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Statically define and initialize a pipe.
*
* The pipe can be accessed outside the module where it is defined using:
*
* @code extern struct k_pipe <name>; @endcode
*
* @param name Name of the pipe.
* @param pipe_buffer_size Size of the pipe's ring buffer (in bytes),
* or zero if no ring buffer is used.
* @param pipe_align Alignment of the pipe's ring buffer (power of 2).
*/
#define K_PIPE_DEFINE(name, pipe_buffer_size, pipe_align) \
static unsigned char __noinit __aligned(pipe_align) \
_k_pipe_buf_##name[pipe_buffer_size]; \
struct k_pipe name \
__in_section(_k_pipe, static, name) = \
_K_PIPE_INITIALIZER(name, _k_pipe_buf_##name, pipe_buffer_size)
/**
* @brief Initialize a pipe.
*
* This routine initializes a pipe object, prior to its first use.
*
* @param pipe Address of the pipe.
* @param buffer Address of the pipe's ring buffer, or NULL if no ring buffer
* is used.
* @param size Size of the pipe's ring buffer (in bytes), or zero if no ring
* buffer is used.
*
* @return N/A
*/
extern void k_pipe_init(struct k_pipe *pipe, unsigned char *buffer,
size_t size);
/**
* @brief Write data to a pipe.
*
* This routine writes up to @a bytes_to_write bytes of data to @a pipe.
*
* @param pipe Address of the pipe.
* @param data Address of data to write.
* @param bytes_to_write Size of data (in bytes).
* @param bytes_written Address of area to hold the number of bytes written.
* @param min_xfer Minimum number of bytes to write.
* @param timeout Waiting period to wait for the data to be written (in
* milliseconds), or one of the special values K_NO_WAIT
* and K_FOREVER.
*
* @retval 0 At least @a min_xfer bytes of data were written.
* @retval -EIO Returned without waiting; zero data bytes were written.
* @retval -EAGAIN Waiting period timed out; between zero and @a min_xfer
* minus one data bytes were written.
*/
extern int k_pipe_put(struct k_pipe *pipe, void *data,
size_t bytes_to_write, size_t *bytes_written,
size_t min_xfer, s32_t timeout);
/**
* @brief Read data from a pipe.
*
* This routine reads up to @a bytes_to_read bytes of data from @a pipe.
*
* @param pipe Address of the pipe.
* @param data Address to place the data read from pipe.
* @param bytes_to_read Maximum number of data bytes to read.
* @param bytes_read Address of area to hold the number of bytes read.
* @param min_xfer Minimum number of data bytes to read.
* @param timeout Waiting period to wait for the data to be read (in
* milliseconds), or one of the special values K_NO_WAIT
* and K_FOREVER.
*
* @retval 0 At least @a min_xfer bytes of data were read.
* @retval -EIO Returned without waiting; zero data bytes were read.
* @retval -EAGAIN Waiting period timed out; between zero and @a min_xfer
* minus one data bytes were read.
*/
extern int k_pipe_get(struct k_pipe *pipe, void *data,
size_t bytes_to_read, size_t *bytes_read,
size_t min_xfer, s32_t timeout);
/**
* @brief Write memory block to a pipe.
*
* This routine writes the data contained in a memory block to @a pipe.
* Once all of the data in the block has been written to the pipe, it will
* free the memory block @a block and give the semaphore @a sem (if specified).
*
* @param pipe Address of the pipe.
* @param block Memory block containing data to send
* @param size Number of data bytes in memory block to send
* @param sem Semaphore to signal upon completion (else NULL)
*
* @return N/A
*/
extern void k_pipe_block_put(struct k_pipe *pipe, struct k_mem_block *block,
size_t size, struct k_sem *sem);
/**
* @} end defgroup pipe_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_mem_slab {
_wait_q_t wait_q;
u32_t num_blocks;
size_t block_size;
char *buffer;
char *free_list;
u32_t num_used;
_OBJECT_TRACING_NEXT_PTR(k_mem_slab);
};
#define _K_MEM_SLAB_INITIALIZER(obj, slab_buffer, slab_block_size, \
slab_num_blocks) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.num_blocks = slab_num_blocks, \
.block_size = slab_block_size, \
.buffer = slab_buffer, \
.free_list = NULL, \
.num_used = 0, \
_OBJECT_TRACING_INIT \
}
#define K_MEM_SLAB_INITIALIZER DEPRECATED_MACRO _K_MEM_SLAB_INITIALIZER
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @defgroup mem_slab_apis Memory Slab APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Statically define and initialize a memory slab.
*
* The memory slab's buffer contains @a slab_num_blocks memory blocks
* that are @a slab_block_size bytes long. The buffer is aligned to a
* @a slab_align -byte boundary. To ensure that each memory block is similarly
* aligned to this boundary, @a slab_block_size must also be a multiple of
* @a slab_align.
*
* The memory slab can be accessed outside the module where it is defined
* using:
*
* @code extern struct k_mem_slab <name>; @endcode
*
* @param name Name of the memory slab.
* @param slab_block_size Size of each memory block (in bytes).
* @param slab_num_blocks Number memory blocks.
* @param slab_align Alignment of the memory slab's buffer (power of 2).
*/
#define K_MEM_SLAB_DEFINE(name, slab_block_size, slab_num_blocks, slab_align) \
char __noinit __aligned(slab_align) \
_k_mem_slab_buf_##name[(slab_num_blocks) * (slab_block_size)]; \
struct k_mem_slab name \
__in_section(_k_mem_slab, static, name) = \
_K_MEM_SLAB_INITIALIZER(name, _k_mem_slab_buf_##name, \
slab_block_size, slab_num_blocks)
/**
* @brief Initialize a memory slab.
*
* Initializes a memory slab, prior to its first use.
*
* The memory slab's buffer contains @a slab_num_blocks memory blocks
* that are @a slab_block_size bytes long. The buffer must be aligned to an
* N-byte boundary, where N is a power of 2 larger than 2 (i.e. 4, 8, 16, ...).
* To ensure that each memory block is similarly aligned to this boundary,
* @a slab_block_size must also be a multiple of N.
*
* @param slab Address of the memory slab.
* @param buffer Pointer to buffer used for the memory blocks.
* @param block_size Size of each memory block (in bytes).
* @param num_blocks Number of memory blocks.
*
* @return N/A
*/
extern void k_mem_slab_init(struct k_mem_slab *slab, void *buffer,
size_t block_size, u32_t num_blocks);
/**
* @brief Allocate memory from a memory slab.
*
* This routine allocates a memory block from a memory slab.
*
* @param slab Address of the memory slab.
* @param mem Pointer to block address area.
* @param timeout Maximum time to wait for operation to complete
* (in milliseconds). Use K_NO_WAIT to return without waiting,
* or K_FOREVER to wait as long as necessary.
*
* @retval 0 Memory allocated. The block address area pointed at by @a mem
* is set to the starting address of the memory block.
* @retval -ENOMEM Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mem_slab_alloc(struct k_mem_slab *slab, void **mem,
s32_t timeout);
/**
* @brief Free memory allocated from a memory slab.
*
* This routine releases a previously allocated memory block back to its
* associated memory slab.
*
* @param slab Address of the memory slab.
* @param mem Pointer to block address area (as set by k_mem_slab_alloc()).
*
* @return N/A
*/
extern void k_mem_slab_free(struct k_mem_slab *slab, void **mem);
/**
* @brief Get the number of used blocks in a memory slab.
*
* This routine gets the number of memory blocks that are currently
* allocated in @a slab.
*
* @param slab Address of the memory slab.
*
* @return Number of allocated memory blocks.
*/
static inline u32_t k_mem_slab_num_used_get(struct k_mem_slab *slab)
{
return slab->num_used;
}
/**
* @brief Get the number of unused blocks in a memory slab.
*
* This routine gets the number of memory blocks that are currently
* unallocated in @a slab.
*
* @param slab Address of the memory slab.
*
* @return Number of unallocated memory blocks.
*/
static inline u32_t k_mem_slab_num_free_get(struct k_mem_slab *slab)
{
return slab->num_blocks - slab->num_used;
}
/**
* @} end defgroup mem_slab_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_mem_pool_lvl {
union {
u32_t *bits_p;
u32_t bits;
};
sys_dlist_t free_list;
};
struct k_mem_pool {
void *buf;
size_t max_sz;
u16_t n_max;
u8_t n_levels;
u8_t max_inline_level;
struct k_mem_pool_lvl *levels;
_wait_q_t wait_q;
};
#define _ALIGN4(n) ((((n)+3)/4)*4)
#define _MPOOL_HAVE_LVL(max, min, l) (((max) >> (2*(l))) >= (min) ? 1 : 0)
#define _MPOOL_LVLS(maxsz, minsz) \
(_MPOOL_HAVE_LVL(maxsz, minsz, 0) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 1) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 2) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 3) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 4) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 5) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 6) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 7) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 8) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 9) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 10) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 11) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 12) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 13) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 14) + \
_MPOOL_HAVE_LVL(maxsz, minsz, 15))
/* Rounds the needed bits up to integer multiples of u32_t */
#define _MPOOL_LBIT_WORDS_UNCLAMPED(n_max, l) \
((((n_max) << (2*(l))) + 31) / 32)
/* One word gets stored free unioned with the pointer, otherwise the
* calculated unclamped value
*/
#define _MPOOL_LBIT_WORDS(n_max, l) \
(_MPOOL_LBIT_WORDS_UNCLAMPED(n_max, l) < 2 ? 0 \
: _MPOOL_LBIT_WORDS_UNCLAMPED(n_max, l))
/* How many bytes for the bitfields of a single level? */
#define _MPOOL_LBIT_BYTES(maxsz, minsz, l, n_max) \
(_MPOOL_LVLS((maxsz), (minsz)) >= (l) ? \
4 * _MPOOL_LBIT_WORDS((n_max), l) : 0)
/* Size of the bitmap array that follows the buffer in allocated memory */
#define _MPOOL_BITS_SIZE(maxsz, minsz, n_max) \
(_MPOOL_LBIT_BYTES(maxsz, minsz, 0, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 1, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 2, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 3, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 4, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 5, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 6, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 7, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 8, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 9, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 10, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 11, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 12, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 13, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 14, n_max) + \
_MPOOL_LBIT_BYTES(maxsz, minsz, 15, n_max))
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @addtogroup mem_pool_apis
* @{
*/
/**
* @brief Statically define and initialize a memory pool.
*
* The memory pool's buffer contains @a n_max blocks that are @a max_size bytes
* long. The memory pool allows blocks to be repeatedly partitioned into
* quarters, down to blocks of @a min_size bytes long. The buffer is aligned
* to a @a align -byte boundary.
*
* If the pool is to be accessed outside the module where it is defined, it
* can be declared via
*
* @code extern struct k_mem_pool <name>; @endcode
*
* @param name Name of the memory pool.
* @param minsz Size of the smallest blocks in the pool (in bytes).
* @param maxsz Size of the largest blocks in the pool (in bytes).
* @param nmax Number of maximum sized blocks in the pool.
* @param align Alignment of the pool's buffer (power of 2).
*/
#define K_MEM_POOL_DEFINE(name, minsz, maxsz, nmax, align) \
char __aligned(align) _mpool_buf_##name[_ALIGN4(maxsz * nmax) \
+ _MPOOL_BITS_SIZE(maxsz, minsz, nmax)]; \
struct k_mem_pool_lvl _mpool_lvls_##name[_MPOOL_LVLS(maxsz, minsz)]; \
struct k_mem_pool name __in_section(_k_mem_pool, static, name) = { \
.buf = _mpool_buf_##name, \
.max_sz = maxsz, \
.n_max = nmax, \
.n_levels = _MPOOL_LVLS(maxsz, minsz), \
.levels = _mpool_lvls_##name, \
}
/**
* @brief Allocate memory from a memory pool.
*
* This routine allocates a memory block from a memory pool.
*
* @param pool Address of the memory pool.
* @param block Pointer to block descriptor for the allocated memory.
* @param size Amount of memory to allocate (in bytes).
* @param timeout Maximum time to wait for operation to complete
* (in milliseconds). Use K_NO_WAIT to return without waiting,
* or K_FOREVER to wait as long as necessary.
*
* @retval 0 Memory allocated. The @a data field of the block descriptor
* is set to the starting address of the memory block.
* @retval -ENOMEM Returned without waiting.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_mem_pool_alloc(struct k_mem_pool *pool, struct k_mem_block *block,
size_t size, s32_t timeout);
/**
* @brief Free memory allocated from a memory pool.
*
* This routine releases a previously allocated memory block back to its
* memory pool.
*
* @param block Pointer to block descriptor for the allocated memory.
*
* @return N/A
*/
extern void k_mem_pool_free(struct k_mem_block *block);
/**
* @brief Defragment a memory pool.
*
* This is a no-op API preserved for backward compatibility only.
*
* @param pool Unused
*
* @return N/A
*/
static inline void __deprecated k_mem_pool_defrag(struct k_mem_pool *pool) {}
/**
* @} end addtogroup mem_pool_apis
*/
/**
* @defgroup heap_apis Heap Memory Pool APIs
* @ingroup kernel_apis
* @{
*/
/**
* @brief Allocate memory from heap.
*
* This routine provides traditional malloc() semantics. Memory is
* allocated from the heap memory pool.
*
* @param size Amount of memory requested (in bytes).
*
* @return Address of the allocated memory if successful; otherwise NULL.
*/
extern void *k_malloc(size_t size);
/**
* @brief Free memory allocated from heap.
*
* This routine provides traditional free() semantics. The memory being
* returned must have been allocated from the heap memory pool.
*
* If @a ptr is NULL, no operation is performed.
*
* @param ptr Pointer to previously allocated memory.
*
* @return N/A
*/
extern void k_free(void *ptr);
/**
* @} end defgroup heap_apis
*/
/* polling API - PRIVATE */
#ifdef CONFIG_POLL
#define _INIT_OBJ_POLL_EVENT(obj) do { (obj)->poll_event = NULL; } while ((0))
#else
#define _INIT_OBJ_POLL_EVENT(obj) do { } while ((0))
#endif
/* private - implementation data created as needed, per-type */
struct _poller {
struct k_thread *thread;
};
/* private - types bit positions */
enum _poll_types_bits {
/* can be used to ignore an event */
_POLL_TYPE_IGNORE,
/* to be signaled by k_poll_signal() */
_POLL_TYPE_SIGNAL,
/* semaphore availability */
_POLL_TYPE_SEM_AVAILABLE,
/* queue/fifo/lifo data availability */
_POLL_TYPE_DATA_AVAILABLE,
_POLL_NUM_TYPES
};
#define _POLL_TYPE_BIT(type) (1 << ((type) - 1))
/* private - states bit positions */
enum _poll_states_bits {
/* default state when creating event */
_POLL_STATE_NOT_READY,
/* signaled by k_poll_signal() */
_POLL_STATE_SIGNALED,
/* semaphore is available */
_POLL_STATE_SEM_AVAILABLE,
/* data is available to read on queue/fifo/lifo */
_POLL_STATE_DATA_AVAILABLE,
_POLL_NUM_STATES
};
#define _POLL_STATE_BIT(state) (1 << ((state) - 1))
#define _POLL_EVENT_NUM_UNUSED_BITS \
(32 - (0 \
+ 8 /* tag */ \
+ _POLL_NUM_TYPES \
+ _POLL_NUM_STATES \
+ 1 /* modes */ \
))
#if _POLL_EVENT_NUM_UNUSED_BITS < 0
#error overflow of 32-bit word in struct k_poll_event
#endif
/* end of polling API - PRIVATE */
/**
* @defgroup poll_apis Async polling APIs
* @ingroup kernel_apis
* @{
*/
/* Public polling API */
/* public - values for k_poll_event.type bitfield */
#define K_POLL_TYPE_IGNORE 0
#define K_POLL_TYPE_SIGNAL _POLL_TYPE_BIT(_POLL_TYPE_SIGNAL)
#define K_POLL_TYPE_SEM_AVAILABLE _POLL_TYPE_BIT(_POLL_TYPE_SEM_AVAILABLE)
#define K_POLL_TYPE_DATA_AVAILABLE _POLL_TYPE_BIT(_POLL_TYPE_DATA_AVAILABLE)
#define K_POLL_TYPE_FIFO_DATA_AVAILABLE K_POLL_TYPE_DATA_AVAILABLE
/* public - polling modes */
enum k_poll_modes {
/* polling thread does not take ownership of objects when available */
K_POLL_MODE_NOTIFY_ONLY = 0,
K_POLL_NUM_MODES
};
/* public - values for k_poll_event.state bitfield */
#define K_POLL_STATE_NOT_READY 0
#define K_POLL_STATE_SIGNALED _POLL_STATE_BIT(_POLL_STATE_SIGNALED)
#define K_POLL_STATE_SEM_AVAILABLE _POLL_STATE_BIT(_POLL_STATE_SEM_AVAILABLE)
#define K_POLL_STATE_DATA_AVAILABLE _POLL_STATE_BIT(_POLL_STATE_DATA_AVAILABLE)
#define K_POLL_STATE_FIFO_DATA_AVAILABLE K_POLL_STATE_DATA_AVAILABLE
/* public - poll signal object */
struct k_poll_signal {
/* PRIVATE - DO NOT TOUCH */
sys_dlist_t poll_events;
/*
* 1 if the event has been signaled, 0 otherwise. Stays set to 1 until
* user resets it to 0.
*/
unsigned int signaled;
/* custom result value passed to k_poll_signal() if needed */
int result;
};
#define K_POLL_SIGNAL_INITIALIZER(obj) \
{ \
.poll_events = SYS_DLIST_STATIC_INIT(&obj.poll_events), \
.signaled = 0, \
.result = 0, \
}
struct k_poll_event {
/* PRIVATE - DO NOT TOUCH */
sys_dnode_t _node;
/* PRIVATE - DO NOT TOUCH */
struct _poller *poller;
/* optional user-specified tag, opaque, untouched by the API */
u32_t tag:8;
/* bitfield of event types (bitwise-ORed K_POLL_TYPE_xxx values) */
u32_t type:_POLL_NUM_TYPES;
/* bitfield of event states (bitwise-ORed K_POLL_STATE_xxx values) */
u32_t state:_POLL_NUM_STATES;
/* mode of operation, from enum k_poll_modes */
u32_t mode:1;
/* unused bits in 32-bit word */
u32_t unused:_POLL_EVENT_NUM_UNUSED_BITS;
/* per-type data */
union {
void *obj;
struct k_poll_signal *signal;
struct k_sem *sem;
struct k_fifo *fifo;
struct k_queue *queue;
};
};
#define K_POLL_EVENT_INITIALIZER(event_type, event_mode, event_obj) \
{ \
.poller = NULL, \
.type = event_type, \
.state = K_POLL_STATE_NOT_READY, \
.mode = event_mode, \
.unused = 0, \
{ .obj = event_obj }, \
}
#define K_POLL_EVENT_STATIC_INITIALIZER(event_type, event_mode, event_obj, \
event_tag) \
{ \
.type = event_type, \
.tag = event_tag, \
.state = K_POLL_STATE_NOT_READY, \
.mode = event_mode, \
.unused = 0, \
{ .obj = event_obj }, \
}
/**
* @brief Initialize one struct k_poll_event instance
*
* After this routine is called on a poll event, the event it ready to be
* placed in an event array to be passed to k_poll().
*
* @param event The event to initialize.
* @param type A bitfield of the types of event, from the K_POLL_TYPE_xxx
* values. Only values that apply to the same object being polled
* can be used together. Choosing K_POLL_TYPE_IGNORE disables the
* event.
* @param mode Future. Use K_POLL_MODE_NOTIFY_ONLY.
* @param obj Kernel object or poll signal.
*
* @return N/A
*/
extern void k_poll_event_init(struct k_poll_event *event, u32_t type,
int mode, void *obj);
/**
* @brief Wait for one or many of multiple poll events to occur
*
* This routine allows a thread to wait concurrently for one or many of
* multiple poll events to have occurred. Such events can be a kernel object
* being available, like a semaphore, or a poll signal event.
*
* When an event notifies that a kernel object is available, the kernel object
* is not "given" to the thread calling k_poll(): it merely signals the fact
* that the object was available when the k_poll() call was in effect. Also,
* all threads trying to acquire an object the regular way, i.e. by pending on
* the object, have precedence over the thread polling on the object. This
* means that the polling thread will never get the poll event on an object
* until the object becomes available and its pend queue is empty. For this
* reason, the k_poll() call is more effective when the objects being polled
* only have one thread, the polling thread, trying to acquire them.
*
* When k_poll() returns 0, the caller should loop on all the events that were
* passed to k_poll() and check the state field for the values that were
* expected and take the associated actions.
*
* Before being reused for another call to k_poll(), the user has to reset the
* state field to K_POLL_STATE_NOT_READY.
*
* @param events An array of pointers to events to be polled for.
* @param num_events The number of events in the array.
* @param timeout Waiting period for an event to be ready (in milliseconds),
* or one of the special values K_NO_WAIT and K_FOREVER.
*
* @retval 0 One or more events are ready.
* @retval -EAGAIN Waiting period timed out.
*/
extern int k_poll(struct k_poll_event *events, int num_events,
s32_t timeout);
/**
* @brief Initialize a poll signal object.
*
* Ready a poll signal object to be signaled via k_poll_signal().
*
* @param signal A poll signal.
*
* @return N/A
*/
extern void k_poll_signal_init(struct k_poll_signal *signal);
/**
* @brief Signal a poll signal object.
*
* This routine makes ready a poll signal, which is basically a poll event of
* type K_POLL_TYPE_SIGNAL. If a thread was polling on that event, it will be
* made ready to run. A @a result value can be specified.
*
* The poll signal contains a 'signaled' field that, when set by
* k_poll_signal(), stays set until the user sets it back to 0. It thus has to
* be reset by the user before being passed again to k_poll() or k_poll() will
* consider it being signaled, and will return immediately.
*
* @param signal A poll signal.
* @param result The value to store in the result field of the signal.
*
* @retval 0 The signal was delivered successfully.
* @retval -EAGAIN The polling thread's timeout is in the process of expiring.
*/
extern int k_poll_signal(struct k_poll_signal *signal, int result);
/* private internal function */
extern int _handle_obj_poll_events(sys_dlist_t *events, u32_t state);
/**
* @} end defgroup poll_apis
*/
/**
* @brief Make the CPU idle.
*
* This function makes the CPU idle until an event wakes it up.
*
* In a regular system, the idle thread should be the only thread responsible
* for making the CPU idle and triggering any type of power management.
* However, in some more constrained systems, such as a single-threaded system,
* the only thread would be responsible for this if needed.
*
* @return N/A
*/
extern void k_cpu_idle(void);
/**
* @brief Make the CPU idle in an atomic fashion.
*
* Similar to k_cpu_idle(), but called with interrupts locked if operations
* must be done atomically before making the CPU idle.
*
* @param key Interrupt locking key obtained from irq_lock().
*
* @return N/A
*/
extern void k_cpu_atomic_idle(unsigned int key);
extern void _sys_power_save_idle_exit(s32_t ticks);
#include <arch/cpu.h>
#ifdef _ARCH_EXCEPT
/* This archtecture has direct support for triggering a CPU exception */
#define _k_except_reason(reason) _ARCH_EXCEPT(reason)
#else
#include <misc/printk.h>
/* NOTE: This is the implementation for arches that do not implement
* _ARCH_EXCEPT() to generate a real CPU exception.
*
* We won't have a real exception frame to determine the PC value when
* the oops occurred, so print file and line number before we jump into
* the fatal error handler.
*/
#define _k_except_reason(reason) do { \
printk("@ %s:%d:\n", __FILE__, __LINE__); \
_NanoFatalErrorHandler(reason, &_default_esf); \
CODE_UNREACHABLE; \
} while (0)
#endif /* _ARCH__EXCEPT */
/**
* @brief Fatally terminate a thread
*
* This should be called when a thread has encountered an unrecoverable
* runtime condition and needs to terminate. What this ultimately
* means is determined by the _fatal_error_handler() implementation, which
* will be called will reason code _NANO_ERR_KERNEL_OOPS.
*
* If this is called from ISR context, the default system fatal error handler
* will treat it as an unrecoverable system error, just like k_panic().
*/
#define k_oops() _k_except_reason(_NANO_ERR_KERNEL_OOPS)
/**
* @brief Fatally terminate the system
*
* This should be called when the Zephyr kernel has encountered an
* unrecoverable runtime condition and needs to terminate. What this ultimately
* means is determined by the _fatal_error_handler() implementation, which
* will be called will reason code _NANO_ERR_KERNEL_PANIC.
*/
#define k_panic() _k_except_reason(_NANO_ERR_KERNEL_PANIC)
/*
* private APIs that are utilized by one or more public APIs
*/
#ifdef CONFIG_MULTITHREADING
extern void _init_static_threads(void);
#else
#define _init_static_threads() do { } while ((0))
#endif
extern int _is_thread_essential(void);
extern void _timer_expiration_handler(struct _timeout *t);
/* arch/cpu.h may declare an architecture or platform-specific macro
* for properly declaring stacks, compatible with MMU/MPU constraints if
* enabled
*/
#ifdef _ARCH_THREAD_STACK_DEFINE
#define K_THREAD_STACK_DEFINE(sym, size) _ARCH_THREAD_STACK_DEFINE(sym, size)
#define K_THREAD_STACK_ARRAY_DEFINE(sym, nmemb, size) \
_ARCH_THREAD_STACK_ARRAY_DEFINE(sym, nmemb, size)
#define K_THREAD_STACK_MEMBER(sym, size) _ARCH_THREAD_STACK_MEMBER(sym, size)
#define K_THREAD_STACK_SIZEOF(sym) _ARCH_THREAD_STACK_SIZEOF(sym)
static inline char *K_THREAD_STACK_BUFFER(k_thread_stack_t sym)
{
return _ARCH_THREAD_STACK_BUFFER(sym);
}
#else
/**
* @brief Declare a toplevel thread stack memory region
*
* This declares a region of memory suitable for use as a thread's stack.
*
* This is the generic, historical definition. Align to STACK_ALIGN and put in
* 'noinit' section so that it isn't zeroed at boot
*
* The declared symbol will always be a k_thread_stack_t which can be passed to
* k_thread_create, but should otherwise not be manipulated. If the buffer
* inside needs to be examined, use K_THREAD_STACK_BUFFER().
*
* It is legal to precede this definition with the 'static' keyword.
*
* It is NOT legal to take the sizeof(sym) and pass that to the stackSize
* parameter of k_thread_create(), it may not be the same as the
* 'size' parameter. Use K_THREAD_STACK_SIZEOF() instead.
*
* @param sym Thread stack symbol name
* @param size Size of the stack memory region
*/
#define K_THREAD_STACK_DEFINE(sym, size) \
struct _k_thread_stack_element __noinit __aligned(STACK_ALIGN) sym[size]
/**
* @brief Declare a toplevel array of thread stack memory regions
*
* Create an array of equally sized stacks. See K_THREAD_STACK_DEFINE
* definition for additional details and constraints.
*
* This is the generic, historical definition. Align to STACK_ALIGN and put in
* 'noinit' section so that it isn't zeroed at boot
*
* @param sym Thread stack symbol name
* @param nmemb Number of stacks to declare
* @param size Size of the stack memory region
*/
#define K_THREAD_STACK_ARRAY_DEFINE(sym, nmemb, size) \
struct _k_thread_stack_element __noinit \
__aligned(STACK_ALIGN) sym[nmemb][size]
/**
* @brief Declare an embedded stack memory region
*
* Used for stacks embedded within other data structures. Use is highly
* discouraged but in some cases necessary. For memory protection scenarios,
* it is very important that any RAM preceding this member not be writable
* by threads else a stack overflow will lead to silent corruption. In other
* words, the containing data structure should live in RAM owned by the kernel.
*
* @param sym Thread stack symbol name
* @param size Size of the stack memory region
*/
#define K_THREAD_STACK_MEMBER(sym, size) \
struct _k_thread_stack_element __aligned(STACK_ALIGN) sym[size]
/**
* @brief Return the size in bytes of a stack memory region
*
* Convenience macro for passing the desired stack size to k_thread_create()
* since the underlying implementation may actually create something larger
* (for instance a guard area).
*
* The value returned here is guaranteed to match the 'size' parameter
* passed to K_THREAD_STACK_DEFINE.
*
* Do not use this for stacks declared with K_THREAD_STACK_ARRAY_DEFINE(),
* it is not guaranteed to return the original value since each array
* element must be aligned.
*
* @param sym Stack memory symbol
* @return Size of the stack
*/
#define K_THREAD_STACK_SIZEOF(sym) sizeof(sym)
/**
* @brief Get a pointer to the physical stack buffer
*
* Convenience macro to get at the real underlying stack buffer used by
* the CPU. Guaranteed to be a character pointer of size K_THREAD_STACK_SIZEOF.
* This is really only intended for diagnostic tools which want to examine
* stack memory contents.
*
* @param sym Declared stack symbol name
* @return The buffer itself, a char *
*/
static inline char *K_THREAD_STACK_BUFFER(k_thread_stack_t sym)
{
return (char *)sym;
}
#endif /* _ARCH_DECLARE_STACK */
#ifdef __cplusplus
}
#endif
#if defined(CONFIG_CPLUSPLUS) && defined(__cplusplus)
/*
* Define new and delete operators.
* At this moment, the operators do nothing since objects are supposed
* to be statically allocated.
*/
inline void operator delete(void *ptr)
{
(void)ptr;
}
inline void operator delete[](void *ptr)
{
(void)ptr;
}
inline void *operator new(size_t size)
{
(void)size;
return NULL;
}
inline void *operator new[](size_t size)
{
(void)size;
return NULL;
}
/* Placement versions of operator new and delete */
inline void operator delete(void *ptr1, void *ptr2)
{
(void)ptr1;
(void)ptr2;
}
inline void operator delete[](void *ptr1, void *ptr2)
{
(void)ptr1;
(void)ptr2;
}
inline void *operator new(size_t size, void *ptr)
{
(void)size;
return ptr;
}
inline void *operator new[](size_t size, void *ptr)
{
(void)size;
return ptr;
}
#endif /* defined(CONFIG_CPLUSPLUS) && defined(__cplusplus) */
#endif /* !_ASMLANGUAGE */
#endif /* _kernel__h_ */