incubator-nuttx/include/nuttx/wqueue.h

473 lines
16 KiB
C

/****************************************************************************
* include/nuttx/wqueue.h
*
* Copyright (C) 2009, 2011-2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_WQUEUE_H
#define __INCLUDE_NUTTX_WQUEUE_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <semaphore.h>
#include <queue.h>
#include <nuttx/clock.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* CONFIG_SCHED_WORKQUEUE. Not selectable. Set by the configuration system
* if either CONFIG_SCHED_HPWORK or CONFIG_SCHED_LPWORK are selected.
* CONFIG_SCHED_HPWORK. Create a dedicated "worker" thread to
* handle delayed processing from interrupt handlers. This feature
* is required for some drivers but, if there are not complaints,
* can be safely disabled. The worker thread also performs
* garbage collection -- completing any delayed memory deallocations
* from interrupt handlers. If the worker thread is disabled,
* then that clean will be performed by the IDLE thread instead
* (which runs at the lowest of priority and may not be appropriate
* if memory reclamation is of high priority). If CONFIG_SCHED_HPWORK
* is enabled, then the following options can also be used:
* CONFIG_SCHED_HPWORKPRIORITY - The execution priority of the high-
* priority worker thread. Default: 224
* CONFIG_SCHED_HPWORKPERIOD - How often the worker thread checks for
* work in units of microseconds. If the high priority worker thread is
* performing garbage collection, then the default is 50*1000 (50 MS).
* Otherwise, if the lower priority worker thread is performing garbage
* collection, the default is 100*1000.
* CONFIG_SCHED_HPWORKSTACKSIZE - The stack size allocated for the worker
* thread. Default: 2048.
* CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
* the worker thread. Default: 17
*
* CONFIG_SCHED_LPWORK. If CONFIG_SCHED_LPWORK is selected then a lower-
* priority work queue will be created. This lower priority work queue
* is better suited for more extended processing (such as file system
* clean-up operations)
* CONFIG_SCHED_LPNTHREADS - The number of thread in the low-priority queue's
* thread pool. Default: 1
* CONFIG_SCHED_LPWORKPRIORITY - The minimum execution priority of the lower
* priority worker thread. Default: 50
* CONFIG_SCHED_LPWORKPRIOMAX - The maximum execution priority of the lower
* priority worker thread. Default: 176
* CONFIG_SCHED_LPWORKPERIOD - How often the lower priority worker thread
* checks for work in units of microseconds. Default: 50*1000 (50 MS).
* CONFIG_SCHED_LPWORKSTACKSIZE - The stack size allocated for the lower
* priority worker thread. Default: 2048.
*
* The user-mode work queue is only available in the protected or kernel
* builds. This those configurations, the user-mode work queue provides the
* same (non-standard) facility for use by applications.
*
* CONFIG_LIB_USRWORK. If CONFIG_LIB_USRWORK is also defined then the
* user-mode work queue will be created.
* CONFIG_LIB_USRWORKPRIORITY - The minimum execution priority of the lower
* priority worker thread. Default: 100
* CONFIG_LIB_USRWORKPERIOD - How often the lower priority worker thread
* checks for work in units of microseconds. Default: 100*1000 (100 MS).
* CONFIG_LIB_USRWORKSTACKSIZE - The stack size allocated for the lower
* priority worker thread. Default: 2048.
*/
/* Is this a protected build (CONFIG_BUILD_PROTECTED=y) */
#if defined(CONFIG_BUILD_PROTECTED)
/* Yes.. kernel worker threads are not built in a kernel build when we are
* building the user-space libraries.
*/
# ifndef __KERNEL__
# undef CONFIG_SCHED_HPWORK
# undef CONFIG_SCHED_LPWORK
# undef CONFIG_SCHED_WORKQUEUE
/* User-space worker threads are not built in a kernel build when we are
* building the kernel-space libraries (but we still need to know that it
* is configured).
*/
# endif
#elif defined(CONFIG_BUILD_KERNEL)
/* The kernel only build is equivalent to the kernel part of the protected
* build.
*/
#else
/* User-space worker threads are not built in a flat build
* (CONFIG_BUILD_PROTECTED=n && CONFIG_BUILD_KERNEL=n)
*/
# undef CONFIG_LIB_USRWORK
#endif
#if defined(CONFIG_SCHED_WORKQUEUE) || defined(CONFIG_LIB_USRWORK)
/* High priority, kernel work queue configuration ***************************/
#ifdef CONFIG_SCHED_HPWORK
# ifndef CONFIG_SCHED_HPWORKPRIORITY
# define CONFIG_SCHED_HPWORKPRIORITY 224
# endif
# ifndef CONFIG_SCHED_HPWORKPERIOD
# ifdef CONFIG_SCHED_LPWORK
# define CONFIG_SCHED_HPWORKPERIOD (100*1000) /* 100 milliseconds */
# else
# define CONFIG_SCHED_HPWORKPERIOD (50*1000) /* 50 milliseconds */
# endif
# endif
# ifndef CONFIG_SCHED_HPWORKSTACKSIZE
# define CONFIG_SCHED_HPWORKSTACKSIZE CONFIG_IDLETHREAD_STACKSIZE
# endif
#endif /* CONFIG_SCHED_HPWORK */
/* Low priority kernel work queue configuration *****************************/
#ifdef CONFIG_SCHED_LPWORK
# ifndef CONFIG_SCHED_LPNTHREADS
# define CONFIG_SCHED_LPNTHREADS 1
#endif
# ifndef CONFIG_SCHED_LPWORKPRIORITY
# define CONFIG_SCHED_LPWORKPRIORITY 50
# endif
# ifndef CONFIG_SCHED_LPWORKPRIOMAX
# ifdef CONFIG_SCHED_HPWORK
# define CONFIG_SCHED_LPWORKPRIOMAX (CONFIG_SCHED_HPWORKPRIORITY-16)
# else
# define CONFIG_SCHED_LPWORKPRIOMAX 176
# endif
# endif
# ifdef CONFIG_SCHED_HPWORK
# if CONFIG_SCHED_LPWORKPRIORITY >= CONFIG_SCHED_HPWORKPRIORITY
# error CONFIG_SCHED_LPWORKPRIORITY >= CONFIG_SCHED_HPWORKPRIORITY
# endif
# if CONFIG_SCHED_LPWORKPRIOMAX >= CONFIG_SCHED_HPWORKPRIORITY
# error CONFIG_SCHED_LPWORKPRIOMAX >= CONFIG_SCHED_HPWORKPRIORITY
# endif
# endif
# if CONFIG_SCHED_LPWORKPRIORITY > CONFIG_SCHED_LPWORKPRIOMAX
# error CONFIG_SCHED_LPWORKPRIORITY > CONFIG_SCHED_LPWORKPRIOMAX
# endif
# ifndef CONFIG_SCHED_LPWORKPERIOD
# define CONFIG_SCHED_LPWORKPERIOD (50*1000) /* 50 milliseconds */
# endif
# ifndef CONFIG_SCHED_LPWORKSTACKSIZE
# define CONFIG_SCHED_LPWORKSTACKSIZE CONFIG_IDLETHREAD_STACKSIZE
# endif
# ifdef CONFIG_WORK_HPWORK
/* The high priority worker thread should be higher priority than the low
* priority worker thread.
*/
# if CONFIG_SCHED_LPWORKPRIORITY > CONFIG_SCHED_HPWORKPRIORITY
# warning "The Lower priority worker thread has the higher priority"
# endif
#endif
#endif /* CONFIG_SCHED_LPWORK */
/* User space work queue configuration **************************************/
#ifdef CONFIG_LIB_USRWORK
# ifndef CONFIG_LIB_USRWORKPRIORITY
# define CONFIG_LIB_USRWORKPRIORITY 100
# endif
# ifndef CONFIG_LIB_USRWORKPERIOD
# define CONFIG_LIB_USRWORKPERIOD (100*1000) /* 100 milliseconds */
# endif
# ifndef CONFIG_LIB_USRWORKSTACKSIZE
# define CONFIG_LIB_USRWORKSTACKSIZE CONFIG_IDLETHREAD_STACKSIZE
# endif
#endif /* CONFIG_LIB_USRWORK */
/* Work queue IDs:
*
* Kernel Work Queues:
* HPWORK: This ID of the high priority work queue that should only be
* used for hi-priority, time-critical, driver bottom-half functions.
*
* LPWORK: This is the ID of the low priority work queue that can be
* used for any purpose. if CONFIG_SCHED_LPWORK is not defined, then
* there is only one kernel work queue and LPWORK == HPWORK.
*
* User Work Queue:
* USRWORK: In the kernel phase a a kernel build, there should be no
* references to user-space work queues. That would be an error.
* Otherwise, in a flat build, user applications will use the lower
* priority work queue (if there is one).
*/
#if defined(CONFIG_LIB_USRWORK) && !defined(__KERNEL__)
/* User mode */
# define USRWORK 2 /* User mode work queue */
# define HPWORK USRWORK /* Redirect kernel-mode references */
# define LPWORK USRWORK
#else
/* Kernel mode */
# define HPWORK 0 /* High priority, kernel-mode work queue */
# ifdef CONFIG_SCHED_LPWORK
# define LPWORK (HPWORK+1) /* Low priority, kernel-mode work queue */
# else
# define LPWORK HPWORK /* Redirect low-priority references */
# endif
# define USRWORK LPWORK /* Redirect user-mode references */
#endif /* CONFIG_LIB_USRWORK && !__KERNEL__ */
/****************************************************************************
* Public Types
****************************************************************************/
#ifndef __ASSEMBLY__
/* Defines the work callback */
typedef void (*worker_t)(FAR void *arg);
/* Defines one entry in the work queue. The user only needs this structure
* in order to declare instances of the work structure. Handling of all
* fields is performed by the work APIs
*/
struct work_s
{
struct dq_entry_s dq; /* Implements a doubly linked list */
worker_t worker; /* Work callback */
FAR void *arg; /* Callback argument */
systime_t qtime; /* Time work queued */
systime_t delay; /* Delay until work performed */
};
/****************************************************************************
* Public Data
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: work_usrstart
*
* Description:
* Start the user mode work queue.
*
* Input parameters:
* None
*
* Returned Value:
* The task ID of the worker thread is returned on success. A negated
* errno value is returned on failure.
*
****************************************************************************/
#if defined(CONFIG_LIB_USRWORK) && !defined(__KERNEL__)
int work_usrstart(void);
#endif
/****************************************************************************
* Name: work_queue
*
* Description:
* Queue work to be performed at a later time. All queued work will be
* performed on the worker thread of execution (not the caller's).
*
* The work structure is allocated by caller, but completely managed by
* the work queue logic. The caller should never modify the contents of
* the work queue structure; the caller should not call work_queue()
* again until either (1) the previous work has been performed and removed
* from the queue, or (2) work_cancel() has been called to cancel the work
* and remove it from the work queue.
*
* Input parameters:
* qid - The work queue ID
* work - The work structure to queue
* worker - The worker callback to be invoked. The callback will invoked
* on the worker thread of execution.
* arg - The argument that will be passed to the worker callback when
* it is invoked.
* delay - Delay (in clock ticks) from the time queue until the worker
* is invoked. Zero means to perform the work immediately.
*
* Returned Value:
* Zero on success, a negated errno on failure
*
****************************************************************************/
int work_queue(int qid, FAR struct work_s *work, worker_t worker,
FAR void *arg, systime_t delay);
/****************************************************************************
* Name: work_cancel
*
* Description:
* Cancel previously queued work. This removes work from the work queue.
* After work has been cancelled, it may be re-queue by calling work_queue()
* again.
*
* Input parameters:
* qid - The work queue ID
* work - The previously queue work structure to cancel
*
* Returned Value:
* Zero on success, a negated errno on failure
*
* -ENOENT - There is no such work queued.
* -EINVAL - An invalid work queue was specified
*
****************************************************************************/
int work_cancel(int qid, FAR struct work_s *work);
/****************************************************************************
* Name: work_signal
*
* Description:
* Signal the worker thread to process the work queue now. This function
* is used internally by the work logic but could also be used by the
* user to force an immediate re-assessment of pending work.
*
* Input parameters:
* qid - The work queue ID
*
* Returned Value:
* Zero on success, a negated errno on failure
*
****************************************************************************/
int work_signal(int qid);
/****************************************************************************
* Name: work_available
*
* Description:
* Check if the work structure is available.
*
* Input parameters:
* work - The work queue structure to check.
* None
*
* Returned Value:
* true if available; false if busy (i.e., there is still pending work).
*
****************************************************************************/
#define work_available(work) ((work)->worker == NULL)
/****************************************************************************
* Name: lpwork_boostpriority
*
* Description:
* Called by the work queue client to assure that the priority of the low-
* priority worker thread is at least at the requested level, reqprio. This
* function would normally be called just before calling work_queue().
*
* Parameters:
* reqprio - Requested minimum worker thread priority
*
* Return Value:
* None
*
****************************************************************************/
#if defined(CONFIG_SCHED_LPWORK) && defined(CONFIG_PRIORITY_INHERITANCE)
void lpwork_boostpriority(uint8_t reqprio);
#endif
/****************************************************************************
* Name: lpwork_restorepriority
*
* Description:
* This function is called to restore the priority after it was previously
* boosted. This is often done by client logic on the worker thread when
* the scheduled work completes. It will check if we need to drop the
* priority of the worker thread.
*
* Parameters:
* reqprio - Previously requested minimum worker thread priority to be
* "unboosted"
*
* Return Value:
* None
*
****************************************************************************/
#if defined(CONFIG_SCHED_LPWORK) && defined(CONFIG_PRIORITY_INHERITANCE)
void lpwork_restorepriority(uint8_t reqprio);
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* CONFIG_SCHED_WORKQUEUE || CONFIG_LIB_USRWORK */
#endif /* __INCLUDE_NUTTX_WQUEUE_H */