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Primary Git Repository for the Zephyr Project. Zephyr is a new generation, scalable, optimized, secure RTOS for multiple hardware architectures.
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zephyr/include/kernel.h

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/*
* Copyright (c) 2016, Wind River Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
*
* @brief Public kernel APIs.
*/
#ifndef _kernel__h_
#define _kernel__h_
#include <stddef.h>
#include <stdint.h>
#include <toolchain.h>
#include <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>
#ifdef __cplusplus
extern "C" {
#endif
#ifdef CONFIG_KERNEL_DEBUG
#include <misc/printk.h>
#define K_DEBUG(fmt, ...) printk("[%s] " fmt, __func__, ##__VA_ARGS__)
#else
#define K_DEBUG(fmt, ...)
#endif
#define K_PRIO_COOP(x) (-(CONFIG_NUM_COOP_PRIORITIES - (x)))
#define K_PRIO_PREEMPT(x) (x)
#define K_ANY NULL
#define K_END NULL
#if CONFIG_NUM_COOP_PRIORITIES > 0
#define K_HIGHEST_THREAD_PRIO (-CONFIG_NUM_COOP_PRIORITIES)
#else
#define K_HIGHEST_THREAD_PRIO 0
#endif
#if CONFIG_NUM_PREEMPT_PRIORITIES > 0
#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
#define tcs k_thread
struct k_thread;
struct k_mutex;
struct k_sem;
struct k_alert;
struct k_msgq;
struct k_mbox;
struct k_pipe;
struct k_fifo;
struct k_lifo;
struct k_stack;
struct k_mem_slab;
struct k_mem_pool;
struct k_timer;
typedef struct k_thread *k_tid_t;
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);
/**
* @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.
*
* 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).
*
* @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_spawn(char *stack, size_t stack_size,
k_thread_entry_t entry,
void *p1, void *p2, void *p3,
int prio, uint32_t options, int32_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(int32_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(uint32_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 cancelled.
* @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)
#ifdef CONFIG_SYS_CLOCK_EXISTS
#define _THREAD_TIMEOUT_INIT(obj) \
(obj).nano_timeout = { \
.node = { {0}, {0} }, \
.thread = NULL, \
.wait_q = NULL, \
.delta_ticks_from_prev = _INACTIVE, \
},
#else
#define _THREAD_TIMEOUT_INIT(obj)
#endif
#ifdef CONFIG_ERRNO
#define _THREAD_ERRNO_INIT(obj) (obj).errno_var = 0,
#else
#define _THREAD_ERRNO_INIT(obj)
#endif
struct _static_thread_data {
union {
char *init_stack;
struct k_thread *thread;
};
unsigned int init_stack_size;
void (*init_entry)(void *, void *, void *);
void *init_p1;
void *init_p2;
void *init_p3;
int init_prio;
uint32_t init_options;
int32_t init_delay;
void (*init_abort)(void);
uint32_t init_groups;
};
#define _THREAD_INITIALIZER(stack, stack_size, \
entry, p1, p2, p3, \
prio, options, delay, abort, groups) \
{ \
.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) \
char __noinit __stack _k_thread_obj_##name[stack_size]; \
struct _static_thread_data _k_thread_data_##name __aligned(4) \
__in_section(_static_thread_data, static, name) = \
_THREAD_INITIALIZER(_k_thread_obj_##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 pre-empted 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(int32_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 int32_t _ms_to_ticks(int32_t ms);
#else
static ALWAYS_INLINE int32_t _ms_to_ticks(int32_t ms)
{
return (int32_t)ceiling_fraction((uint32_t)ms, _ms_per_tick);
}
#endif
/* added tick needed to account for tick in progress */
#define _TICK_ALIGN 1
static inline int64_t __ticks_to_ms(int64_t ticks)
{
#ifdef CONFIG_SYS_CLOCK_EXISTS
#ifdef _NON_OPTIMIZED_TICKS_PER_SEC
return (MSEC_PER_SEC * (uint64_t)ticks) / sys_clock_ticks_per_sec;
#else
return (uint64_t)ticks * _ms_per_tick;
#endif
#else
__ASSERT(ticks == 0, "");
return 0;
#endif
}
/* 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;
int32_t delta_ticks_from_prev;
_timeout_func_t func;
};
extern int32_t _timeout_remaining_get(struct _timeout *timeout);
/**
* INTERNAL_HIDDEN @endcond
*/
/**
* @cond INTERNAL_HIDDEN
*/
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 */
int32_t period;
/* timer status */
uint32_t status;
/* used to support legacy timer APIs */
void *_legacy_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, \
._legacy_data = NULL, \
_OBJECT_TRACING_INIT \
}
/**
* 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,
int32_t duration, int32_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.
*
* @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 uint32_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 uint32_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 int32_t k_timer_remaining_get(struct k_timer *timer)
{
return _timeout_remaining_get(&timer->timeout);
}
/**
* @} 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 int64_t k_uptime_get(void);
/**
* @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 uint32_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 int64_t k_uptime_delta(int64_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 uint32_t k_uptime_delta_32(int64_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).
*/
extern uint32_t k_cycle_get_32(void);
/**
* @} end addtogroup clock_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_fifo {
_wait_q_t wait_q;
sys_slist_t data_q;
_OBJECT_TRACING_NEXT_PTR(k_fifo);
};
#define K_FIFO_INITIALIZER(obj) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.data_q = SYS_SLIST_STATIC_INIT(&obj.data_q), \
_OBJECT_TRACING_INIT \
}
/**
* 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
*/
extern void k_fifo_init(struct k_fifo *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
*/
extern void k_fifo_put(struct k_fifo *fifo, void *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
*/
extern void k_fifo_put_list(struct k_fifo *fifo, void *head, void *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
*/
extern void k_fifo_put_slist(struct k_fifo *fifo, sys_slist_t *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.
*/
extern void *k_fifo_get(struct k_fifo *fifo, int32_t timeout);
/**
* @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_fifo, static, name) = \
K_FIFO_INITIALIZER(name)
/**
* @} end defgroup fifo_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_lifo {
_wait_q_t wait_q;
void *list;
_OBJECT_TRACING_NEXT_PTR(k_lifo);
};
#define K_LIFO_INITIALIZER(obj) \
{ \
.wait_q = SYS_DLIST_STATIC_INIT(&obj.wait_q), \
.list = NULL, \
_OBJECT_TRACING_INIT \
}
/**
* 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
*/
extern void k_lifo_init(struct k_lifo *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
*/
extern void k_lifo_put(struct k_lifo *lifo, void *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.
*/
extern void *k_lifo_get(struct k_lifo *lifo, int32_t 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_lifo, static, name) = \
K_LIFO_INITIALIZER(name)
/**
* @} end defgroup lifo_apis
*/
/**
* @cond INTERNAL_HIDDEN
*/
struct k_stack {
_wait_q_t wait_q;
uint32_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 \
}
/**
* 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,
uint32_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, uint32_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, uint32_t *data, int32_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) \
uint32_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_fifo fifo;
};
enum {
K_WORK_STATE_PENDING, /* Work item pending state */
};
struct k_work {
void *_reserved; /* Used by k_fifo 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
*/
/**
* @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 struct k_work <work> = K_WORK_INITIALIZER(<work_handler>); @endcode
*
* @param work_handler Function to invoke each time work item is processed.
*/
#define K_WORK_INITIALIZER(work_handler) \
{ \
._reserved = NULL, \
.handler = work_handler, \
.flags = { 0 } \
}
/**
* @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_fifo_put(&work_q->fifo, 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.
* @param stack_size Size of the work queue thread's stack (in bytes).
* @param prio Priority of the work queue's thread.
*
* @return N/A
*/
extern void k_work_q_start(struct k_work_q *work_q, char *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 asychronous 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,
int32_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 cancelled while its countdown is still
* underway.
*
* @note Can be called by ISRs.
*
* @param work Address of delayed work item.
*
* @retval 0 Work item countdown cancelled.
* @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 asychronous 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,
int32_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 int32_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;
uint32_t lock_count;
int owner_orig_prio;
#ifdef CONFIG_OBJECT_MONITOR
int num_lock_state_changes;
int num_conflicts;
#endif
_OBJECT_TRACING_NEXT_PTR(k_mutex);
};
#ifdef CONFIG_OBJECT_MONITOR
#define _MUTEX_INIT_OBJECT_MONITOR \
.num_lock_state_changes = 0, .num_conflicts = 0,
#else
#define _MUTEX_INIT_OBJECT_MONITOR
#endif
#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, \
_MUTEX_INIT_OBJECT_MONITOR \
_OBJECT_TRACING_INIT \
}
/**
* 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, int32_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;
_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, \
_OBJECT_TRACING_INIT \
}
/**
* 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, int32_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 signalled. 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 \
}
/**
* 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, int32_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;
uint32_t max_msgs;
char *buffer_start;
char *buffer_end;
char *read_ptr;
char *write_ptr;
uint32_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 \
}
/**
* 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, uint32_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, int32_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, int32_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 uint32_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 uint32_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
* @{
*/
struct k_mem_block {
struct k_mem_pool *pool_id;
void *addr_in_pool;
void *data;
size_t req_size;
};
/**
* @} 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 */
uint32_t _mailbox;
/** size of message (in bytes) */
size_t size;
/** application-defined information value */
uint32_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 \
}
/**
* 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,
int32_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, int32_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, int32_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 \
}
/**
* 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, int32_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, int32_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;
uint32_t num_blocks;
size_t block_size;
char *buffer;
char *free_list;
uint32_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 \
}
/**
* 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, uint32_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,
int32_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 uint32_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 uint32_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
*/
/*
* Memory pool requires a buffer and two arrays of structures for the
* memory block accounting:
* A set of arrays of k_mem_pool_quad_block structures where each keeps a
* status of four blocks of memory.
*/
struct k_mem_pool_quad_block {
char *mem_blocks; /* pointer to the first of four memory blocks */
uint32_t mem_status; /* four bits. If bit is set, memory block is
allocated */
};
/*
* Memory pool mechanism uses one array of k_mem_pool_quad_block for accounting
* blocks of one size. Block sizes go from maximal to minimal. Next memory
* block size is 4 times less than the previous one and thus requires 4 times
* bigger array of k_mem_pool_quad_block structures to keep track of the
* memory blocks.
*/
/*
* The array of k_mem_pool_block_set keeps the information of each array of
* k_mem_pool_quad_block structures
*/
struct k_mem_pool_block_set {
size_t block_size; /* memory block size */
uint32_t nr_of_entries; /* nr of quad block structures in the array */
struct k_mem_pool_quad_block *quad_block;
int count;
};
/* Memory pool descriptor */
struct k_mem_pool {
size_t max_block_size;
size_t min_block_size;
uint32_t nr_of_maxblocks;
uint32_t nr_of_block_sets;
struct k_mem_pool_block_set *block_set;
char *bufblock;
_wait_q_t wait_q;
_OBJECT_TRACING_NEXT_PTR(k_mem_pool);
};
#ifdef CONFIG_ARM
#define _SECTION_TYPE_SIGN "%"
#else
#define _SECTION_TYPE_SIGN "@"
#endif
/*
* Static memory pool initialization
*/
/*
* Use .altmacro to be able to recalculate values and pass them as string
* arguments when calling assembler macros resursively
*/
__asm__(".altmacro\n\t");
/*
* Recursively calls a macro
* The followig global symbols need to be initialized:
* __memory_pool_max_block_size - maximal size of the memory block
* __memory_pool_min_block_size - minimal size of the memory block
* Notes:
* Global symbols are used due the fact that assembler macro allows only
* one argument be passed with the % conversion
* Some assemblers do not get division operation ("/"). To avoid it >> 2
* is used instead of / 4.
* n_max argument needs to go first in the invoked macro, as some
* assemblers concatenate \name and %(\n_max * 4) arguments
* if \name goes first
*/
__asm__(".macro __do_recurse macro_name, name, n_max\n\t"
".ifge __memory_pool_max_block_size >> 2 -"
" __memory_pool_min_block_size\n\t\t"
"__memory_pool_max_block_size = __memory_pool_max_block_size >> 2\n\t\t"
"\\macro_name %(\\n_max * 4) \\name\n\t"
".endif\n\t"
".endm\n");
/*
* Build quad blocks
* Macro allocates space in memory for the array of k_mem_pool_quad_block
* structures and recursively calls itself for the next array, 4 times
* larger.
* The followig global symbols need to be initialized:
* __memory_pool_max_block_size - maximal size of the memory block
* __memory_pool_min_block_size - minimal size of the memory block
* __memory_pool_quad_block_size - sizeof(struct k_mem_pool_quad_block)
*/
__asm__(".macro _build_quad_blocks n_max, name\n\t"
".balign 4\n\t"
"_mem_pool_quad_blocks_\\name\\()_\\n_max:\n\t"
".skip __memory_pool_quad_block_size * \\n_max >> 2\n\t"
".if \\n_max % 4\n\t\t"
".skip __memory_pool_quad_block_size\n\t"
".endif\n\t"
"__do_recurse _build_quad_blocks \\name \\n_max\n\t"
".endm\n");
/*
* Build block sets and initialize them
* Macro initializes the k_mem_pool_block_set structure and
* recursively calls itself for the next one.
* The followig global symbols need to be initialized:
* __memory_pool_max_block_size - maximal size of the memory block
* __memory_pool_min_block_size - minimal size of the memory block
* __memory_pool_block_set_count, the number of the elements in the
* block set array must be set to 0. Macro calculates it's real
* value.
* Since the macro initializes pointers to an array of k_mem_pool_quad_block
* structures, _build_quad_blocks must be called prior it.
*/
__asm__(".macro _build_block_set n_max, name\n\t"
".int __memory_pool_max_block_size\n\t" /* block_size */
".if \\n_max % 4\n\t\t"
".int \\n_max >> 2 + 1\n\t" /* nr_of_entries */
".else\n\t\t"
".int \\n_max >> 2\n\t"
".endif\n\t"
".int _mem_pool_quad_blocks_\\name\\()_\\n_max\n\t" /* quad_block */
".int 0\n\t" /* count */
"__memory_pool_block_set_count = __memory_pool_block_set_count + 1\n\t"
"__do_recurse _build_block_set \\name \\n_max\n\t"
".endm\n");
/*
* Build a memory pool structure and initialize it
* Macro uses __memory_pool_block_set_count global symbol,
* block set addresses and buffer address, it may be called only after
* _build_block_set
*/
__asm__(".macro _build_mem_pool name, min_size, max_size, n_max\n\t"
".pushsection ._k_mem_pool.static.\\name,\"aw\","
_SECTION_TYPE_SIGN "progbits\n\t"
".globl \\name\n\t"
"\\name:\n\t"
".int \\max_size\n\t" /* max_block_size */
".int \\min_size\n\t" /* min_block_size */
".int \\n_max\n\t" /* nr_of_maxblocks */
".int __memory_pool_block_set_count\n\t" /* nr_of_block_sets */
".int _mem_pool_block_sets_\\name\n\t" /* block_set */
".int _mem_pool_buffer_\\name\n\t" /* bufblock */
".int 0\n\t" /* wait_q->head */
".int 0\n\t" /* wait_q->next */
".popsection\n\t"
".endm\n");
#define _MEMORY_POOL_QUAD_BLOCK_DEFINE(name, min_size, max_size, n_max) \
__asm__(".pushsection ._k_memory_pool.struct,\"aw\"," \
_SECTION_TYPE_SIGN "progbits\n\t"); \
__asm__("__memory_pool_min_block_size = " STRINGIFY(min_size) "\n\t"); \
__asm__("__memory_pool_max_block_size = " STRINGIFY(max_size) "\n\t"); \
__asm__("_build_quad_blocks " STRINGIFY(n_max) " " \
STRINGIFY(name) "\n\t"); \
__asm__(".popsection\n\t")
#define _MEMORY_POOL_BLOCK_SETS_DEFINE(name, min_size, max_size, n_max) \
__asm__("__memory_pool_block_set_count = 0\n\t"); \
__asm__("__memory_pool_max_block_size = " STRINGIFY(max_size) "\n\t"); \
__asm__(".pushsection ._k_memory_pool.struct,\"aw\"," \
_SECTION_TYPE_SIGN "progbits\n\t"); \
__asm__(".balign 4\n\t"); \
__asm__("_mem_pool_block_sets_" STRINGIFY(name) ":\n\t"); \
__asm__("_build_block_set " STRINGIFY(n_max) " " \
STRINGIFY(name) "\n\t"); \
__asm__("_mem_pool_block_set_count_" STRINGIFY(name) ":\n\t"); \
__asm__(".int __memory_pool_block_set_count\n\t"); \
__asm__(".popsection\n\t"); \
extern uint32_t _mem_pool_block_set_count_##name; \
extern struct k_mem_pool_block_set _mem_pool_block_sets_##name[]
#define _MEMORY_POOL_BUFFER_DEFINE(name, max_size, n_max, align) \
char __noinit __aligned(align) \
_mem_pool_buffer_##name[(max_size) * (n_max)]
/*
* Dummy function that assigns the value of sizeof(struct k_mem_pool_quad_block)
* to __memory_pool_quad_block_size absolute symbol.
* This function does not get called, but compiler calculates the value and
* assigns it to the absolute symbol, that, in turn is used by assembler macros.
*/
static void __attribute__ ((used)) __k_mem_pool_quad_block_size_define(void)
{
__asm__(".globl __memory_pool_quad_block_size\n\t"
#ifdef CONFIG_NIOS2
"__memory_pool_quad_block_size = %0\n\t"
#else
"__memory_pool_quad_block_size = %c0\n\t"
#endif
:
: "n"(sizeof(struct k_mem_pool_quad_block)));
}
/**
* 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. To ensure that the minimum sized blocks are
* similarly aligned to this boundary, @a min_size must also be a multiple of
* @a align.
*
* 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 min_size Size of the smallest blocks in the pool (in bytes).
* @param max_size Size of the largest blocks in the pool (in bytes).
* @param n_max 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, min_size, max_size, n_max, align) \
_MEMORY_POOL_QUAD_BLOCK_DEFINE(name, min_size, max_size, n_max); \
_MEMORY_POOL_BLOCK_SETS_DEFINE(name, min_size, max_size, n_max); \
_MEMORY_POOL_BUFFER_DEFINE(name, max_size, n_max, align); \
__asm__("_build_mem_pool " STRINGIFY(name) " " STRINGIFY(min_size) " " \
STRINGIFY(max_size) " " STRINGIFY(n_max) "\n\t"); \
extern struct k_mem_pool 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, int32_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 routine instructs a memory pool to concatenate unused memory blocks
* into larger blocks wherever possible. Manually defragmenting the memory
* pool may speed up future allocations of memory blocks by eliminating the
* need for the memory pool to perform an automatic partial defragmentation.
*
* @param pool Address of the memory pool.
*
* @return N/A
*/
extern void 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
*/
/**
* @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);
/*
* legacy.h must be before arch/cpu.h to allow the ioapic/loapic drivers to
* hook into the device subsystem, which itself uses nanokernel semaphores,
* and thus currently requires the definition of nano_sem.
*/
#include <legacy.h>
#include <arch/cpu.h>
/*
* 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);
#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 /* _kernel__h_ */