1 /**
2 * @file daemon/opd_kernel.c
3 * Dealing with the kernel and kernel module samples
4 *
5 * @remark Copyright 2002 OProfile authors
6 * @remark Read the file COPYING
7 *
8 * @author John Levon
9 * @author Philippe Elie
10 * Modified by Aravind Menon for Xen
11 * These modifications are:
12 * Copyright (C) 2005 Hewlett-Packard Co.
13 */
14
15 #include "opd_kernel.h"
16 #include "opd_sfile.h"
17 #include "opd_trans.h"
18 #include "opd_printf.h"
19 #include "opd_stats.h"
20 #include "oprofiled.h"
21
22 #include "op_fileio.h"
23 #include "op_config.h"
24 #include "op_libiberty.h"
25
26 #include <string.h>
27 #include <stdlib.h>
28 #include <errno.h>
29 #include <assert.h>
30
31 static LIST_HEAD(modules);
32
33 static struct kernel_image vmlinux_image;
34
35 static struct kernel_image xen_image;
36
opd_create_vmlinux(char const * name,char const * arg)37 void opd_create_vmlinux(char const * name, char const * arg)
38 {
39 /* vmlinux is *not* on the list of modules */
40 list_init(&vmlinux_image.list);
41
42 /* for no vmlinux */
43 if (no_vmlinux) {
44 vmlinux_image.name = "no-vmlinux";
45 return;
46 }
47
48 vmlinux_image.name = xstrdup(name);
49
50 sscanf(arg, "%llx,%llx", &vmlinux_image.start, &vmlinux_image.end);
51
52 verbprintf(vmisc, "kernel_start = %llx, kernel_end = %llx\n",
53 vmlinux_image.start, vmlinux_image.end);
54
55 if (!vmlinux_image.start && !vmlinux_image.end) {
56 fprintf(stderr, "error: mis-parsed kernel range: %llx-%llx\n",
57 vmlinux_image.start, vmlinux_image.end);
58 exit(EXIT_FAILURE);
59 }
60 }
61
opd_create_xen(char const * name,char const * arg)62 void opd_create_xen(char const * name, char const * arg)
63 {
64 /* xen is *not* on the list of modules */
65 list_init(&xen_image.list);
66
67 /* for no xen */
68 if (no_xen) {
69 xen_image.name = "no-xen";
70 return;
71 }
72
73 xen_image.name = xstrdup(name);
74
75 sscanf(arg, "%llx,%llx", &xen_image.start, &xen_image.end);
76
77 verbprintf(vmisc, "xen_start = %llx, xen_end = %llx\n",
78 xen_image.start, xen_image.end);
79
80 if (!xen_image.start && !xen_image.end) {
81 fprintf(stderr, "error: mis-parsed xen range: %llx-%llx\n",
82 xen_image.start, xen_image.end);
83 exit(EXIT_FAILURE);
84 }
85 }
86
87
88 /**
89 * Allocate and initialise a kernel image description
90 * @param name image name
91 * @param start start address
92 * @param end end address
93 */
94 static struct kernel_image *
opd_create_module(char const * name,vma_t start,vma_t end)95 opd_create_module(char const * name, vma_t start, vma_t end)
96 {
97 struct kernel_image * image = xmalloc(sizeof(struct kernel_image));
98
99 image->name = xstrdup(name);
100 image->start = start;
101 image->end = end;
102 list_add(&image->list, &modules);
103
104 return image;
105 }
106
107
108 /**
109 * Clear and free all kernel image information and reset
110 * values.
111 */
opd_clear_modules(void)112 static void opd_clear_modules(void)
113 {
114 struct list_head * pos;
115 struct list_head * pos2;
116 struct kernel_image * image;
117
118 list_for_each_safe(pos, pos2, &modules) {
119 image = list_entry(pos, struct kernel_image, list);
120 if (image->name)
121 free(image->name);
122 free(image);
123 }
124
125 list_init(&modules);
126
127 /* clear out lingering references */
128 sfile_clear_kernel();
129 }
130
131
132 /*
133 * each line is in the format:
134 *
135 * module_name 16480 1 dependencies Live 0xe091e000
136 *
137 * without any blank space in each field
138 */
opd_reread_module_info(void)139 void opd_reread_module_info(void)
140 {
141 FILE * fp;
142 char * line;
143 struct kernel_image * image;
144 int module_size;
145 char ref_count[32+1];
146 int ret;
147 char module_name[256+1];
148 char live_info[32+1];
149 char dependencies[4096+1];
150 unsigned long long start_address;
151
152 if (no_vmlinux)
153 return;
154
155 opd_clear_modules();
156
157 printf("Reading module info.\n");
158
159 fp = op_try_open_file("/proc/modules", "r");
160
161 if (!fp) {
162 printf("oprofiled: /proc/modules not readable, "
163 "can't process module samples.\n");
164 return;
165 }
166
167 while (1) {
168 line = op_get_line(fp);
169
170 if (!line)
171 break;
172
173 if (line[0] == '\0') {
174 free(line);
175 continue;
176 }
177
178 ret = sscanf(line, "%256s %u %32s %4096s %32s %llx",
179 module_name, &module_size, ref_count,
180 dependencies, live_info, &start_address);
181 if (ret != 6) {
182 printf("bad /proc/modules entry: %s\n", line);
183 free(line);
184 continue;
185 }
186
187 image = opd_create_module(module_name, start_address,
188 start_address + module_size);
189
190 verbprintf(vmodule, "module %s start %llx end %llx\n",
191 image->name, image->start, image->end);
192
193 free(line);
194 }
195
196 op_close_file(fp);
197 }
198
199
200 /**
201 * find a kernel image by PC value
202 * @param trans holds PC value to look up
203 *
204 * find the kernel image which contains this PC.
205 *
206 * Return %NULL if not found.
207 */
find_kernel_image(struct transient const * trans)208 struct kernel_image * find_kernel_image(struct transient const * trans)
209 {
210 struct list_head * pos;
211 struct kernel_image * image = &vmlinux_image;
212
213 if (no_vmlinux)
214 return image;
215
216 if (image->start <= trans->pc && image->end > trans->pc)
217 return image;
218
219 list_for_each(pos, &modules) {
220 image = list_entry(pos, struct kernel_image, list);
221 if (image->start <= trans->pc && image->end > trans->pc)
222 return image;
223 }
224
225 if (xen_image.start <= trans->pc && xen_image.end > trans->pc)
226 return &xen_image;
227
228 return NULL;
229 }
230