1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019, Matthew Macy <mmacy@freebsd.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 */
28
29 #include <sys/types.h>
30 #include <sys/systm.h>
31 #include <sys/param.h>
32 #include <sys/sbuf.h>
33
34 #include <sys/queue.h>
35 #include <sys/linker.h>
36 #include <sys/module.h>
37 #include <sys/eventhandler.h>
38 #include <sys/kernel.h>
39 #include <sys/malloc.h>
40 #include <sys/syslog.h>
41 #include <sys/proc.h>
42 #include <sys/sched.h>
43 #include <sys/syslog.h>
44 #include <sys/sysctl.h>
45 #include <gnu/gcov/gcov.h>
46 #include <sys/queue.h>
47 #include "linker_if.h"
48
49
50 static void gcov_invoke_ctors(void);
51 static int gcov_ctors_done;
52 int gcov_events_enabled;
53
54 static int
gcov_stats_reset_sysctl(SYSCTL_HANDLER_ARGS)55 gcov_stats_reset_sysctl(SYSCTL_HANDLER_ARGS)
56 {
57 int error, v;
58
59 v = 0;
60 error = sysctl_handle_int(oidp, &v, 0, req);
61 if (error)
62 return (error);
63 if (req->newptr == NULL)
64 return (error);
65 if (v == 0)
66 return (0);
67 gcov_stats_reset();
68
69 return (0);
70 }
71
72 static int
gcov_stats_enable_sysctl(SYSCTL_HANDLER_ARGS)73 gcov_stats_enable_sysctl(SYSCTL_HANDLER_ARGS)
74 {
75 int error, v;
76
77 v = gcov_events_enabled;
78 error = sysctl_handle_int(oidp, &v, v, req);
79 if (error)
80 return (error);
81 if (req->newptr == NULL)
82 return (error);
83 if (v == gcov_events_enabled)
84 return (0);
85 //gcov_events_reset();
86 gcov_events_enabled = !!v;
87 if (!gcov_ctors_done)
88 gcov_invoke_ctors();
89 if (gcov_events_enabled)
90 gcov_enable_events();
91
92 return (0);
93 }
94
95 int
within_module(vm_offset_t addr,module_t mod)96 within_module(vm_offset_t addr, module_t mod)
97 {
98 linker_file_t link_info;
99 vm_offset_t mod_addr;
100 size_t mod_size;
101
102 link_info = module_file(mod);
103 mod_addr = (vm_offset_t)link_info->address;
104 mod_size = link_info->size;
105 if (addr >= mod_addr && addr < mod_addr + mod_size)
106 return (1);
107 return (0);
108 }
109
110
111
112 #define GCOV_PREFIX "_GLOBAL__sub_I_65535_0_"
113
114 static int
gcov_invoke_ctor(const char * name,void * arg)115 gcov_invoke_ctor(const char *name, void *arg)
116 {
117 void (*ctor)(void);
118 c_linker_sym_t sym;
119 linker_symval_t symval;
120 linker_file_t lf;
121
122 if (strstr(name, GCOV_PREFIX) == NULL)
123 return (0);
124 lf = arg;
125 LINKER_LOOKUP_SYMBOL(lf, name, &sym);
126 LINKER_SYMBOL_VALUES(lf, sym, &symval);
127 ctor = (void *)symval.value;
128 ctor();
129 return (0);
130 }
131
132 static int
gcov_invoke_lf_ctors(linker_file_t lf,void * arg __unused)133 gcov_invoke_lf_ctors(linker_file_t lf, void *arg __unused)
134 {
135
136 printf("%s processing file: %s\n", __func__, lf->filename);
137 LINKER_EACH_FUNCTION_NAME(lf, gcov_invoke_ctor, lf);
138 return (0);
139 }
140
141 static void
gcov_invoke_ctors(void)142 gcov_invoke_ctors(void)
143 {
144
145 gcov_fs_init();
146
147 linker_file_foreach(gcov_invoke_lf_ctors, NULL);
148 gcov_ctors_done = 1;
149 }
150
151 static int
gcov_init(void * arg __unused)152 gcov_init(void *arg __unused)
153 {
154 EVENTHANDLER_REGISTER(module_unload, gcov_module_unload, NULL, 0);
155 gcov_enable_events();
156 return (0);
157 }
158
159 SYSINIT(gcov_init, SI_SUB_EVENTHANDLER, SI_ORDER_ANY, gcov_init, NULL);
160
161 static SYSCTL_NODE(_debug, OID_AUTO, gcov, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
162 "gcov code coverage");
163 SYSCTL_PROC(_debug_gcov, OID_AUTO, reset,
164 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, NULL, 0,
165 gcov_stats_reset_sysctl, "I",
166 "Reset all profiling counts");
167 SYSCTL_PROC(_debug_gcov, OID_AUTO, enable,
168 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, NULL, 0,
169 gcov_stats_enable_sysctl, "I",
170 "Enable code coverage");
171