xref: /netbsd-src/external/cddl/osnet/dev/dtrace/dtrace_unload.c (revision ba2539a9805a0544ff82c0003cc02fe1eee5603d)
1 /*	$NetBSD: dtrace_unload.c,v 1.7 2018/05/28 21:05:03 chs Exp $	*/
2 
3 /*
4  * CDDL HEADER START
5  *
6  * The contents of this file are subject to the terms of the
7  * Common Development and Distribution License (the "License").
8  * You may not use this file except in compliance with the License.
9  *
10  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
11  * or http://www.opensolaris.org/os/licensing.
12  * See the License for the specific language governing permissions
13  * and limitations under the License.
14  *
15  * When distributing Covered Code, include this CDDL HEADER in each
16  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
17  * If applicable, add the following below this CDDL HEADER, with the
18  * fields enclosed by brackets "[]" replaced with your own identifying
19  * information: Portions Copyright [yyyy] [name of copyright owner]
20  *
21  * CDDL HEADER END
22  *
23  * $FreeBSD: head/sys/cddl/dev/dtrace/dtrace_unload.c 278166 2015-02-03 19:39:53Z pfg $
24  *
25  */
26 
27 static int
dtrace_unload()28 dtrace_unload()
29 {
30 	dtrace_state_t *state;
31 	int error = 0;
32 
33 #ifdef __FreeBSD__
34 	destroy_dev(dtrace_dev);
35 	destroy_dev(helper_dev);
36 #endif
37 
38 #ifdef __NetBSD__
39 	module_unregister_callbacks(dtrace_modcb);
40 #endif
41 
42 	mutex_enter(&dtrace_provider_lock);
43 	mutex_enter(&dtrace_lock);
44 	mutex_enter(&cpu_lock);
45 
46 	if (dtrace_opens > 0 || dtrace_helpers > 0) {
47 		mutex_exit(&cpu_lock);
48 		mutex_exit(&dtrace_lock);
49 		mutex_exit(&dtrace_provider_lock);
50 		return (EBUSY);
51 	}
52 
53 	if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) {
54 		mutex_exit(&cpu_lock);
55 		mutex_exit(&dtrace_lock);
56 		mutex_exit(&dtrace_provider_lock);
57 		return (EBUSY);
58 	}
59 
60 	dtrace_provider = NULL;
61 #ifdef __FreeBSD__
62 	EVENTHANDLER_DEREGISTER(kld_load, dtrace_kld_load_tag);
63 	EVENTHANDLER_DEREGISTER(kld_unload_try, dtrace_kld_unload_try_tag);
64 #endif
65 
66 	if ((state = dtrace_anon_grab()) != NULL) {
67 		/*
68 		 * If there were ECBs on this state, the provider should
69 		 * have not been allowed to detach; assert that there is
70 		 * none.
71 		 */
72 		ASSERT(state->dts_necbs == 0);
73 		dtrace_state_destroy(state);
74 	}
75 
76 	bzero(&dtrace_anon, sizeof (dtrace_anon_t));
77 
78 	mutex_exit(&cpu_lock);
79 
80 	if (dtrace_probes != NULL) {
81 		kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *));
82 		dtrace_probes = NULL;
83 		dtrace_nprobes = 0;
84 	}
85 
86 	dtrace_hash_destroy(dtrace_bymod);
87 	dtrace_hash_destroy(dtrace_byfunc);
88 	dtrace_hash_destroy(dtrace_byname);
89 	dtrace_bymod = NULL;
90 	dtrace_byfunc = NULL;
91 	dtrace_byname = NULL;
92 
93 	kmem_cache_destroy(dtrace_state_cache);
94 
95 #ifdef __FreeBSD__
96 	delete_unrhdr(dtrace_arena);
97 #endif
98 #ifdef __NetBSD__
99 	vmem_destroy(dtrace_arena);
100 #endif
101 
102 	if (dtrace_toxrange != NULL) {
103 		kmem_free(dtrace_toxrange,
104 		    dtrace_toxranges_max * sizeof (dtrace_toxrange_t));
105 		dtrace_toxrange = NULL;
106 		dtrace_toxranges = 0;
107 		dtrace_toxranges_max = 0;
108 	}
109 
110 	ASSERT(dtrace_vtime_references == 0);
111 	ASSERT(dtrace_opens == 0);
112 	ASSERT(dtrace_retained == NULL);
113 
114 	mutex_exit(&dtrace_lock);
115 	mutex_exit(&dtrace_provider_lock);
116 
117 	mutex_destroy(&dtrace_meta_lock);
118 	mutex_destroy(&dtrace_provider_lock);
119 	mutex_destroy(&dtrace_lock);
120 #ifdef DEBUG
121 	mutex_destroy(&dtrace_errlock);
122 #endif
123 
124 #ifdef __FreeBSD__
125 	taskq_destroy(dtrace_taskq);
126 #endif
127 
128 	/* Reset our hook for exceptions. */
129 	dtrace_invop_uninit();
130 
131 	/*
132 	 * Reset our hook for thread switches, but ensure that vtime isn't
133 	 * active first.
134 	 */
135 	dtrace_vtime_active = 0;
136 	dtrace_vtime_switch_func = NULL;
137 
138 	/* Unhook from the trap handler. */
139 	dtrace_trap_func = NULL;
140 
141 	return (error);
142 }
143