1 // SPDX-License-Identifier: GPL-2.0
2 #include <string.h>
3 #include <stdio.h>
4 #include <sys/types.h>
5 #include <dirent.h>
6 #include <fcntl.h>
7 #include <linux/stddef.h>
8 #include <linux/perf_event.h>
9 #include <linux/zalloc.h>
10 #include <api/fs/fs.h>
11 #include <errno.h>
12
13 #include "../../../util/intel-pt.h"
14 #include "../../../util/intel-bts.h"
15 #include "../../../util/pmu.h"
16 #include "../../../util/fncache.h"
17
18 #define TEMPLATE_ALIAS "%s/bus/event_source/devices/%s/alias"
19
20 struct pmu_alias {
21 char *name;
22 char *alias;
23 struct list_head list;
24 };
25
26 static LIST_HEAD(pmu_alias_name_list);
27 static bool cached_list;
28
perf_pmu__get_default_config(struct perf_pmu * pmu __maybe_unused)29 struct perf_event_attr *perf_pmu__get_default_config(struct perf_pmu *pmu __maybe_unused)
30 {
31 #ifdef HAVE_AUXTRACE_SUPPORT
32 if (!strcmp(pmu->name, INTEL_PT_PMU_NAME))
33 return intel_pt_pmu_default_config(pmu);
34 if (!strcmp(pmu->name, INTEL_BTS_PMU_NAME))
35 pmu->selectable = true;
36 #endif
37 return NULL;
38 }
39
pmu_alias__delete(struct pmu_alias * pmu_alias)40 static void pmu_alias__delete(struct pmu_alias *pmu_alias)
41 {
42 if (!pmu_alias)
43 return;
44
45 zfree(&pmu_alias->name);
46 zfree(&pmu_alias->alias);
47 free(pmu_alias);
48 }
49
pmu_alias__new(char * name,char * alias)50 static struct pmu_alias *pmu_alias__new(char *name, char *alias)
51 {
52 struct pmu_alias *pmu_alias = zalloc(sizeof(*pmu_alias));
53
54 if (pmu_alias) {
55 pmu_alias->name = strdup(name);
56 if (!pmu_alias->name)
57 goto out_delete;
58
59 pmu_alias->alias = strdup(alias);
60 if (!pmu_alias->alias)
61 goto out_delete;
62 }
63 return pmu_alias;
64
65 out_delete:
66 pmu_alias__delete(pmu_alias);
67 return NULL;
68 }
69
setup_pmu_alias_list(void)70 static int setup_pmu_alias_list(void)
71 {
72 char path[PATH_MAX];
73 DIR *dir;
74 struct dirent *dent;
75 const char *sysfs = sysfs__mountpoint();
76 struct pmu_alias *pmu_alias;
77 char buf[MAX_PMU_NAME_LEN];
78 FILE *file;
79 int ret = -ENOMEM;
80
81 if (!sysfs)
82 return -1;
83
84 snprintf(path, PATH_MAX,
85 "%s" EVENT_SOURCE_DEVICE_PATH, sysfs);
86
87 dir = opendir(path);
88 if (!dir)
89 return -errno;
90
91 while ((dent = readdir(dir))) {
92 if (!strcmp(dent->d_name, ".") ||
93 !strcmp(dent->d_name, ".."))
94 continue;
95
96 snprintf(path, PATH_MAX,
97 TEMPLATE_ALIAS, sysfs, dent->d_name);
98
99 if (!file_available(path))
100 continue;
101
102 file = fopen(path, "r");
103 if (!file)
104 continue;
105
106 if (!fgets(buf, sizeof(buf), file)) {
107 fclose(file);
108 continue;
109 }
110
111 fclose(file);
112
113 /* Remove the last '\n' */
114 buf[strlen(buf) - 1] = 0;
115
116 pmu_alias = pmu_alias__new(dent->d_name, buf);
117 if (!pmu_alias)
118 goto close_dir;
119
120 list_add_tail(&pmu_alias->list, &pmu_alias_name_list);
121 }
122
123 ret = 0;
124
125 close_dir:
126 closedir(dir);
127 return ret;
128 }
129
__pmu_find_real_name(const char * name)130 static char *__pmu_find_real_name(const char *name)
131 {
132 struct pmu_alias *pmu_alias;
133
134 list_for_each_entry(pmu_alias, &pmu_alias_name_list, list) {
135 if (!strcmp(name, pmu_alias->alias))
136 return pmu_alias->name;
137 }
138
139 return (char *)name;
140 }
141
pmu_find_real_name(const char * name)142 char *pmu_find_real_name(const char *name)
143 {
144 if (cached_list)
145 return __pmu_find_real_name(name);
146
147 setup_pmu_alias_list();
148 cached_list = true;
149
150 return __pmu_find_real_name(name);
151 }
152
__pmu_find_alias_name(const char * name)153 static char *__pmu_find_alias_name(const char *name)
154 {
155 struct pmu_alias *pmu_alias;
156
157 list_for_each_entry(pmu_alias, &pmu_alias_name_list, list) {
158 if (!strcmp(name, pmu_alias->name))
159 return pmu_alias->alias;
160 }
161 return NULL;
162 }
163
pmu_find_alias_name(const char * name)164 char *pmu_find_alias_name(const char *name)
165 {
166 if (cached_list)
167 return __pmu_find_alias_name(name);
168
169 setup_pmu_alias_list();
170 cached_list = true;
171
172 return __pmu_find_alias_name(name);
173 }
174