xref: /freebsd/contrib/ofed/opensm/include/complib/cl_event.h (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*
2  * Copyright (c) 2004, 2005 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2002-2005 Mellanox Technologies LTD. All rights reserved.
4  * Copyright (c) 1996-2003 Intel Corporation. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  *
34  */
35 
36 /*
37  * Abstract:
38  *	Declaration of event abstraction.
39  */
40 
41 #ifndef _CL_EVENT_H_
42 #define _CL_EVENT_H_
43 
44 /* Indicates that waiting on an event should never timeout */
45 #define EVENT_NO_TIMEOUT	0xFFFFFFFF
46 
47 #include <complib/cl_event_osd.h>
48 
49 #ifdef __cplusplus
50 #  define BEGIN_C_DECLS extern "C" {
51 #  define END_C_DECLS   }
52 #else				/* !__cplusplus */
53 #  define BEGIN_C_DECLS
54 #  define END_C_DECLS
55 #endif				/* __cplusplus */
56 
57 BEGIN_C_DECLS
58 /****h* Component Library/Event
59 * NAME
60 *	Event
61 *
62 * DESCRIPTION
63 *	The Event provides the ability to suspend and wakeup a thread.
64 *
65 *	The event functions operates on a cl_event_t structure which should be
66 *	treated as opaque and should be manipulated only through the provided
67 *	functions.
68 *
69 * SEE ALSO
70 *	Structures:
71 *		cl_event_t
72 *
73 *	Initialization/Destruction:
74 *		cl_event_construct, cl_event_init, cl_event_destroy
75 *
76 *	Manipulation:
77 *		cl_event_signal, cl_event_reset, cl_event_wait_on
78 *********/
79 /****f* Component Library: Event/cl_event_construct
80 * NAME
81 *	cl_event_construct
82 *
83 * DESCRIPTION
84 *	The cl_event_construct function constructs an event.
85 *
86 * SYNOPSIS
87 */
88 void cl_event_construct(IN cl_event_t * const p_event);
89 /*
90 * PARAMETERS
91 *	p_event
92 *		[in] Pointer to an cl_event_t structure to construct.
93 *
94 * RETURN VALUE
95 *	This function does not return a value.
96 *
97 * NOTES
98 *	Allows calling cl_event_destroy without first calling cl_event_init.
99 *
100 *	Calling cl_event_construct is a prerequisite to calling any other event
101 *	function except cl_event_init.
102 *
103 * SEE ALSO
104 *	Event, cl_event_init, cl_event_destroy
105 *********/
106 
107 /****f* Component Library: Event/cl_event_init
108 * NAME
109 *	cl_event_init
110 *
111 * DESCRIPTION
112 *	The cl_event_init function initializes an event for use.
113 *
114 * SYNOPSIS
115 */
116 cl_status_t
117 cl_event_init(IN cl_event_t * const p_event, IN const boolean_t manual_reset);
118 /*
119 * PARAMETERS
120 *	p_event
121 *		[in] Pointer to an cl_event_t structure to initialize.
122 *
123 *	manual_reset
124 *		[in] If FALSE, indicates that the event resets itself after releasing
125 *		a single waiter.  If TRUE, the event remains in the signalled state
126 *		until explicitly reset by a call to cl_event_reset.
127 *
128 * RETURN VALUES
129 *	CL_SUCCESS if event initialization succeeded.
130 *
131 *	CL_ERROR otherwise.
132 *
133 * NOTES
134 *	Allows calling event manipulation functions, such as cl_event_signal,
135 *	cl_event_reset, and cl_event_wait_on.
136 *
137 *	The event is initially in a reset state.
138 *
139 * SEE ALSO
140 *	Event, cl_event_construct, cl_event_destroy, cl_event_signal,
141 *	cl_event_reset, cl_event_wait_on
142 *********/
143 
144 /****f* Component Library: Event/cl_event_destroy
145 * NAME
146 *	cl_event_destroy
147 *
148 * DESCRIPTION
149 *	The cl_event_destroy function performs any necessary cleanup of an event.
150 *
151 * SYNOPSIS
152 */
153 void cl_event_destroy(IN cl_event_t * const p_event);
154 
155 /*
156 * PARAMETERS
157 *	p_event
158 *		[in] Pointer to an cl_event_t structure to destroy.
159 *
160 * RETURN VALUE
161 *	This function does not return a value.
162 *
163 * NOTES
164 *	This function should only be called after a call to cl_event_construct
165 *	or cl_event_init.
166 *
167 * SEE ALSO
168 *	Event, cl_event_construct, cl_event_init
169 *********/
170 
171 /****f* Component Library: Event/cl_event_signal
172 * NAME
173 *	cl_event_signal
174 *
175 * DESCRIPTION
176 *	The cl_event_signal function sets an event to the signalled state and
177 *	releases at most one waiting thread.
178 *
179 * SYNOPSIS
180 */
181 cl_status_t cl_event_signal(IN cl_event_t * const p_event);
182 /*
183 * PARAMETERS
184 *	p_event
185 *		[in] Pointer to an cl_event_t structure to set.
186 *
187 * RETURN VALUES
188 *	CL_SUCCESS if the event was successfully signalled.
189 *
190 *	CL_ERROR otherwise.
191 *
192 * NOTES
193 *	For auto-reset events, the event is reset automatically once a wait
194 *	operation is satisfied.
195 *
196 *	Triggering the event multiple times does not guarantee that the same
197 *	number of wait operations are satisfied. This is because events are
198 *	either in a signalled on non-signalled state, and triggering an event
199 *	that is already in the signalled state has no effect.
200 *
201 * SEE ALSO
202 *	Event, cl_event_reset, cl_event_wait_on
203 *********/
204 
205 /****f* Component Library: Event/cl_event_reset
206 * NAME
207 *	cl_event_reset
208 *
209 * DESCRIPTION
210 *	The cl_event_reset function sets an event to the non-signalled state.
211 *
212 * SYNOPSIS
213 */
214 cl_status_t cl_event_reset(IN cl_event_t * const p_event);
215 /*
216 * PARAMETERS
217 *	p_event
218 *		[in] Pointer to an cl_event_t structure to reset.
219 *
220 * RETURN VALUES
221 *	CL_SUCCESS if the event was successfully reset.
222 *
223 *	CL_ERROR otherwise.
224 *
225 * SEE ALSO
226 *	Event, cl_event_signal, cl_event_wait_on
227 *********/
228 
229 /****f* Component Library: Event/cl_event_wait_on
230 * NAME
231 *	cl_event_wait_on
232 *
233 * DESCRIPTION
234 *	The cl_event_wait_on function waits for the specified event to be
235 *	triggered for a minimum amount of time.
236 *
237 * SYNOPSIS
238 */
239 cl_status_t
240 cl_event_wait_on(IN cl_event_t * const p_event,
241 		 IN const uint32_t wait_us, IN const boolean_t interruptible);
242 /*
243 * PARAMETERS
244 *	p_event
245 *		[in] Pointer to an cl_event_t structure on which to wait.
246 *
247 *	wait_us
248 *		[in] Number of microseconds to wait.
249 *
250 *	interruptible
251 *		[in] Indicates whether the wait operation can be interrupted
252 *		by external signals.
253 *
254 * RETURN VALUES
255 *	CL_SUCCESS if the wait operation succeeded in response to the event
256 *	being set.
257 *
258 *	CL_TIMEOUT if the specified time period elapses.
259 *
260 *	CL_NOT_DONE if the wait was interrupted by an external signal.
261 *
262 *	CL_ERROR if the wait operation failed.
263 *
264 * NOTES
265 *	If wait_us is set to EVENT_NO_TIMEOUT, the function will wait until the
266 *	event is triggered and never timeout.
267 *
268 *	If the timeout value is zero, this function simply tests the state of
269 *	the event.
270 *
271 *	If the event is already on the signalled state at the time of the call
272 *	to cl_event_wait_on, the call completes immediately with CL_SUCCESS.
273 *
274 * SEE ALSO
275 *	Event, cl_event_signal, cl_event_reset
276 *********/
277 
278 END_C_DECLS
279 #endif				/* _CL_EVENT_H_ */
280