xref: /freebsd-12.1/contrib/ntp/lib/isc/taskpool.c (revision 2b15cb3d)
1 /*
2  * Copyright (C) 2004, 2005, 2007, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 1999-2001  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id$ */
19 
20 /*! \file */
21 
22 #include <config.h>
23 
24 #include <isc/mem.h>
25 #include <isc/random.h>
26 #include <isc/taskpool.h>
27 #include <isc/util.h>
28 
29 /***
30  *** Types.
31  ***/
32 
33 struct isc_taskpool {
34 	isc_mem_t *			mctx;
35 	isc_taskmgr_t *			tmgr;
36 	unsigned int			ntasks;
37 	unsigned int			quantum;
38 	isc_task_t **			tasks;
39 };
40 
41 /***
42  *** Functions.
43  ***/
44 
45 static isc_result_t
alloc_pool(isc_taskmgr_t * tmgr,isc_mem_t * mctx,unsigned int ntasks,unsigned int quantum,isc_taskpool_t ** poolp)46 alloc_pool(isc_taskmgr_t *tmgr, isc_mem_t *mctx, unsigned int ntasks,
47 	   unsigned int quantum, isc_taskpool_t **poolp)
48 {
49 	isc_taskpool_t *pool;
50 	unsigned int i;
51 
52 	pool = isc_mem_get(mctx, sizeof(*pool));
53 	if (pool == NULL)
54 		return (ISC_R_NOMEMORY);
55 	pool->mctx = mctx;
56 	pool->ntasks = ntasks;
57 	pool->quantum = quantum;
58 	pool->tmgr = tmgr;
59 	pool->tasks = isc_mem_get(mctx, ntasks * sizeof(isc_task_t *));
60 	if (pool->tasks == NULL) {
61 		isc_mem_put(mctx, pool, sizeof(*pool));
62 		return (ISC_R_NOMEMORY);
63 	}
64 	for (i = 0; i < ntasks; i++)
65 		pool->tasks[i] = NULL;
66 
67 	*poolp = pool;
68 	return (ISC_R_SUCCESS);
69 }
70 
71 isc_result_t
isc_taskpool_create(isc_taskmgr_t * tmgr,isc_mem_t * mctx,unsigned int ntasks,unsigned int quantum,isc_taskpool_t ** poolp)72 isc_taskpool_create(isc_taskmgr_t *tmgr, isc_mem_t *mctx,
73 		    unsigned int ntasks, unsigned int quantum,
74 		    isc_taskpool_t **poolp)
75 {
76 	unsigned int i;
77 	isc_taskpool_t *pool = NULL;
78 	isc_result_t result;
79 
80 	INSIST(ntasks > 0);
81 
82 	/* Allocate the pool structure */
83 	result = alloc_pool(tmgr, mctx, ntasks, quantum, &pool);
84 	if (result != ISC_R_SUCCESS)
85 		return (result);
86 
87 	/* Create the tasks */
88 	for (i = 0; i < ntasks; i++) {
89 		result = isc_task_create(tmgr, quantum, &pool->tasks[i]);
90 		if (result != ISC_R_SUCCESS) {
91 			isc_taskpool_destroy(&pool);
92 			return (result);
93 		}
94 		isc_task_setname(pool->tasks[i], "taskpool", NULL);
95 	}
96 
97 	*poolp = pool;
98 	return (ISC_R_SUCCESS);
99 }
100 
101 void
isc_taskpool_gettask(isc_taskpool_t * pool,isc_task_t ** targetp)102 isc_taskpool_gettask(isc_taskpool_t *pool, isc_task_t **targetp) {
103 	isc_uint32_t i;
104 	isc_random_get(&i);
105 	isc_task_attach(pool->tasks[i % pool->ntasks], targetp);
106 }
107 
108 int
isc_taskpool_size(isc_taskpool_t * pool)109 isc_taskpool_size(isc_taskpool_t *pool) {
110 	REQUIRE(pool != NULL);
111 	return (pool->ntasks);
112 }
113 
114 isc_result_t
isc_taskpool_expand(isc_taskpool_t ** sourcep,unsigned int size,isc_taskpool_t ** targetp)115 isc_taskpool_expand(isc_taskpool_t **sourcep, unsigned int size,
116 		    isc_taskpool_t **targetp)
117 {
118 	isc_result_t result;
119 	isc_taskpool_t *pool;
120 
121 	REQUIRE(sourcep != NULL && *sourcep != NULL);
122 	REQUIRE(targetp != NULL && *targetp == NULL);
123 
124 	pool = *sourcep;
125 	if (size > pool->ntasks) {
126 		isc_taskpool_t *newpool = NULL;
127 		unsigned int i;
128 
129 		/* Allocate a new pool structure */
130 		result = alloc_pool(pool->tmgr, pool->mctx, size,
131 				    pool->quantum, &newpool);
132 		if (result != ISC_R_SUCCESS)
133 			return (result);
134 
135 		/* Copy over the tasks from the old pool */
136 		for (i = 0; i < pool->ntasks; i++) {
137 			newpool->tasks[i] = pool->tasks[i];
138 			pool->tasks[i] = NULL;
139 		}
140 
141 		/* Create new tasks */
142 		for (i = pool->ntasks; i < size; i++) {
143 			result = isc_task_create(pool->tmgr, pool->quantum,
144 						 &newpool->tasks[i]);
145 			if (result != ISC_R_SUCCESS) {
146 				isc_taskpool_destroy(&newpool);
147 				return (result);
148 			}
149 			isc_task_setname(newpool->tasks[i], "taskpool", NULL);
150 		}
151 
152 		isc_taskpool_destroy(&pool);
153 		pool = newpool;
154 	}
155 
156 	*sourcep = NULL;
157 	*targetp = pool;
158 	return (ISC_R_SUCCESS);
159 }
160 
161 void
isc_taskpool_destroy(isc_taskpool_t ** poolp)162 isc_taskpool_destroy(isc_taskpool_t **poolp) {
163 	unsigned int i;
164 	isc_taskpool_t *pool = *poolp;
165 	for (i = 0; i < pool->ntasks; i++) {
166 		if (pool->tasks[i] != NULL)
167 			isc_task_detach(&pool->tasks[i]);
168 	}
169 	isc_mem_put(pool->mctx, pool->tasks,
170 		    pool->ntasks * sizeof(isc_task_t *));
171 	isc_mem_put(pool->mctx, pool, sizeof(*pool));
172 	*poolp = NULL;
173 }
174 
175 void
isc_taskpool_setprivilege(isc_taskpool_t * pool,isc_boolean_t priv)176 isc_taskpool_setprivilege(isc_taskpool_t *pool, isc_boolean_t priv) {
177 	unsigned int i;
178 
179 	REQUIRE(pool != NULL);
180 
181 	for (i = 0; i < pool->ntasks; i++) {
182 		if (pool->tasks[i] != NULL)
183 			isc_task_setprivilege(pool->tasks[i], priv);
184 	}
185 }
186