incubator-nuttx/include/nuttx/wqueue.h

533 lines
18 KiB
C

/****************************************************************************
* include/nuttx/wqueue.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_WQUEUE_H
#define __INCLUDE_NUTTX_WQUEUE_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.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
* 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_HPNTHREADS - The number of thread in the high-priority
* queue's thread pool. Default: 1
* CONFIG_SCHED_HPWORKPRIORITY - The execution priority of the high-
* priority worker thread. Default: 224
* 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_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_USRWORKSTACKSIZE - The stack size allocated for the lower
* priority worker thread. Default: 2048.
*/
/* Is this a flat build (CONFIG_BUILD_FLAT=y) */
#if defined(CONFIG_BUILD_FLAT)
/* Yes.. user-space worker threads are not built in a flat build */
# undef CONFIG_LIB_USRWORK
#elif !defined(__KERNEL__)
/* Kernel worker threads are not built in a kernel build when we are
* building the user-space libraries.
*/
# 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
/* High priority, kernel work queue configuration ***************************/
#ifdef CONFIG_SCHED_HPWORK
# ifndef CONFIG_SCHED_HPNTHREADS
# define CONFIG_SCHED_HPNTHREADS 1
# endif
# ifndef CONFIG_SCHED_HPWORKPRIORITY
# define CONFIG_SCHED_HPWORKPRIORITY 224
# 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_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_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 */
# if defined(CONFIG_SCHED_LPWORK) && defined(CONFIG_SCHED_HPWORK)
# 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 CODE 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 */
clock_t qtime; /* Time work queued */
clock_t delay; /* Delay until work performed */
};
/* This is an enumeration of the various events that may be
* notified via work_notifier_signal().
*/
enum work_evtype_e
{
WORK_IOB_AVAIL = 1, /* Notify availability of an IOB */
WORK_NET_DOWN, /* Notify that the network is down */
WORK_TCP_READAHEAD, /* Notify that TCP read-ahead data is available */
WORK_TCP_WRITEBUFFER, /* Notify that TCP write buffer is empty */
WORK_TCP_DISCONNECT, /* Notify loss of TCP connection */
WORK_UDP_READAHEAD, /* Notify that UDP read-ahead data is available */
WORK_UDP_WRITEBUFFER, /* Notify that UDP write buffer is empty */
WORK_NETLINK_RESPONSE, /* Notify that Netlink response is available */
WORK_CAN_READAHEAD, /* Notify that CAN read-ahead data is available */
WORK_USB_MSC_CONNECT, /* Notify that an USB MSC connect occurred */
WORK_USB_MSC_DISCONNECT /* Notify that an USB MSC connect occurred */
};
/* This structure describes one notification and is provided as input to
* to work_notifier_setup(). This input is copied by work_notifier_setup()
* into an allocated instance of struct work_notifier_entry_s and need not
* persist on the caller's side.
*/
struct work_notifier_s
{
uint8_t evtype; /* See enum work_evtype_e */
uint8_t qid; /* The work queue to use: HPWORK or LPWORK */
FAR void *qualifier; /* Event qualifier value */
FAR void *arg; /* User-defined worker function argument */
worker_t worker; /* The worker function to schedule */
};
/****************************************************************************
* 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 and must be initialized to all zero by
* the caller. Otherwise, the work structure is completely managed by the
* work queue logic. The caller should never modify the contents of the
* work queue structure directly. If work_queue() is called before the
* previous work as been performed and removed from the queue, then any
* pending work will be canceled and lost.
*
* 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, clock_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().
*
* Input Parameters:
* reqprio - Requested minimum worker thread priority
*
* Returned 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.
*
* Input Parameters:
* reqprio - Previously requested minimum worker thread priority to be
* "unboosted"
*
* Returned Value:
* None
*
****************************************************************************/
#if defined(CONFIG_SCHED_LPWORK) && defined(CONFIG_PRIORITY_INHERITANCE)
void lpwork_restorepriority(uint8_t reqprio);
#endif
/****************************************************************************
* Name: work_notifier_setup
*
* Description:
* Set up to provide a notification when event occurs.
*
* Input Parameters:
* info - Describes the work notification.
*
* Returned Value:
* > 0 - The key which may be used later in a call to
* work_notifier_teardown().
* == 0 - Not used (reserved for wrapper functions).
* < 0 - An unexpected error occurred and no notification will be sent.
* The returned value is a negated errno value that indicates the
* nature of the failure.
*
****************************************************************************/
#ifdef CONFIG_WQUEUE_NOTIFIER
int work_notifier_setup(FAR struct work_notifier_s *info);
#endif
/****************************************************************************
* Name: work_notifier_teardown
*
* Description:
* Eliminate a notification previously setup by work_notifier_setup().
* This function should only be called if the notification should be
* aborted prior to the notification. The notification will automatically
* be torn down after the notification is executed.
*
* Input Parameters:
* key - The key value returned from a previous call to
* work_notifier_setup().
*
* Returned Value:
* Zero (OK) is returned on success; a negated errno value is returned on
* any failure.
*
****************************************************************************/
#ifdef CONFIG_WQUEUE_NOTIFIER
int work_notifier_teardown(int key);
#endif
/****************************************************************************
* Name: work_notifier_signal
*
* Description:
* An event has just occurred. Notify all threads waiting for that event.
*
* When an event of interest occurs, *all* of the workers waiting for this
* event will be executed. If there are multiple workers for a resource
* then only the first to execute will get the resource. Others will
* need to call work_notifier_setup() once again.
*
* Input Parameters:
* evtype - The type of the event that just occurred.
* qualifier - Event qualifier to distinguish different cases of the
* generic event type.
*
* Returned Value:
* None.
*
****************************************************************************/
#ifdef CONFIG_WQUEUE_NOTIFIER
void work_notifier_signal(enum work_evtype_e evtype,
FAR void *qualifier);
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* __ASSEMBLY__ */
#endif /* __INCLUDE_NUTTX_WQUEUE_H */