Commit | Line | Data |
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9f36eaed MJ |
1 | /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1) |
2 | * | |
a90917c3 | 3 | * lttng-context.c |
2dccf128 | 4 | * |
2dccf128 | 5 | * LTTng trace/channel/event context management. |
17baffe2 | 6 | * |
886d51a3 | 7 | * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
2dccf128 MD |
8 | */ |
9 | ||
10 | #include <linux/module.h> | |
11 | #include <linux/list.h> | |
12 | #include <linux/mutex.h> | |
13 | #include <linux/slab.h> | |
ea53823c | 14 | #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */ |
241ae9a8 MD |
15 | #include <lttng-events.h> |
16 | #include <lttng-tracer.h> | |
2dccf128 | 17 | |
07dfc1d0 MD |
18 | /* |
19 | * The filter implementation requires that two consecutive "get" for the | |
20 | * same context performed by the same thread return the same result. | |
21 | */ | |
22 | ||
23 | /* | |
24 | * Static array of contexts, for $ctx filters. | |
25 | */ | |
26 | struct lttng_ctx *lttng_static_ctx; | |
27 | ||
44252f0f MD |
28 | int lttng_find_context(struct lttng_ctx *ctx, const char *name) |
29 | { | |
30 | unsigned int i; | |
31 | ||
32 | for (i = 0; i < ctx->nr_fields; i++) { | |
4b58a8e4 MD |
33 | /* Skip allocated (but non-initialized) contexts */ |
34 | if (!ctx->fields[i].event_field.name) | |
35 | continue; | |
44252f0f MD |
36 | if (!strcmp(ctx->fields[i].event_field.name, name)) |
37 | return 1; | |
38 | } | |
39 | return 0; | |
40 | } | |
41 | EXPORT_SYMBOL_GPL(lttng_find_context); | |
42 | ||
07dfc1d0 MD |
43 | int lttng_get_context_index(struct lttng_ctx *ctx, const char *name) |
44 | { | |
45 | unsigned int i; | |
0451bcec | 46 | const char *subname; |
07dfc1d0 MD |
47 | |
48 | if (!ctx) | |
49 | return -1; | |
0451bcec MD |
50 | if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) { |
51 | subname = name + strlen("$ctx."); | |
52 | } else { | |
53 | subname = name; | |
54 | } | |
07dfc1d0 MD |
55 | for (i = 0; i < ctx->nr_fields; i++) { |
56 | /* Skip allocated (but non-initialized) contexts */ | |
57 | if (!ctx->fields[i].event_field.name) | |
58 | continue; | |
0451bcec | 59 | if (!strcmp(ctx->fields[i].event_field.name, subname)) |
07dfc1d0 MD |
60 | return i; |
61 | } | |
62 | return -1; | |
63 | } | |
64 | EXPORT_SYMBOL_GPL(lttng_get_context_index); | |
65 | ||
2001023e MD |
66 | /* |
67 | * Note: as we append context information, the pointer location may change. | |
68 | */ | |
2dccf128 MD |
69 | struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p) |
70 | { | |
71 | struct lttng_ctx_field *field; | |
72 | struct lttng_ctx *ctx; | |
73 | ||
74 | if (!*ctx_p) { | |
75 | *ctx_p = kzalloc(sizeof(struct lttng_ctx), GFP_KERNEL); | |
76 | if (!*ctx_p) | |
77 | return NULL; | |
a9dd15da | 78 | (*ctx_p)->largest_align = 1; |
2dccf128 MD |
79 | } |
80 | ctx = *ctx_p; | |
81 | if (ctx->nr_fields + 1 > ctx->allocated_fields) { | |
82 | struct lttng_ctx_field *new_fields; | |
83 | ||
0f034e0f | 84 | ctx->allocated_fields = max_t(size_t, 1, 2 * ctx->allocated_fields); |
48f5e0b5 | 85 | new_fields = lttng_kvzalloc(ctx->allocated_fields * sizeof(struct lttng_ctx_field), GFP_KERNEL); |
2dccf128 MD |
86 | if (!new_fields) |
87 | return NULL; | |
88 | if (ctx->fields) | |
77aefe99 | 89 | memcpy(new_fields, ctx->fields, sizeof(*ctx->fields) * ctx->nr_fields); |
48f5e0b5 | 90 | lttng_kvfree(ctx->fields); |
2dccf128 MD |
91 | ctx->fields = new_fields; |
92 | } | |
93 | field = &ctx->fields[ctx->nr_fields]; | |
94 | ctx->nr_fields++; | |
95 | return field; | |
96 | } | |
97 | EXPORT_SYMBOL_GPL(lttng_append_context); | |
98 | ||
a9dd15da MD |
99 | /* |
100 | * lttng_context_update() should be called at least once between context | |
101 | * modification and trace start. | |
102 | */ | |
103 | void lttng_context_update(struct lttng_ctx *ctx) | |
104 | { | |
105 | int i; | |
106 | size_t largest_align = 8; /* in bits */ | |
107 | ||
108 | for (i = 0; i < ctx->nr_fields; i++) { | |
109 | struct lttng_type *type; | |
110 | size_t field_align = 8; | |
111 | ||
112 | type = &ctx->fields[i].event_field.type; | |
113 | switch (type->atype) { | |
114 | case atype_integer: | |
115 | field_align = type->u.basic.integer.alignment; | |
116 | break; | |
117 | case atype_array: | |
3834b99f | 118 | case atype_array_bitfield: |
a9dd15da MD |
119 | { |
120 | struct lttng_basic_type *btype; | |
121 | ||
122 | btype = &type->u.array.elem_type; | |
123 | switch (btype->atype) { | |
124 | case atype_integer: | |
125 | field_align = btype->u.basic.integer.alignment; | |
126 | break; | |
127 | case atype_string: | |
128 | break; | |
129 | ||
130 | case atype_array: | |
131 | case atype_sequence: | |
3834b99f MD |
132 | case atype_array_bitfield: |
133 | case atype_sequence_bitfield: | |
f513b2bf MD |
134 | case atype_struct: |
135 | case atype_array_compound: | |
136 | case atype_sequence_compound: | |
65c85aa6 | 137 | case atype_variant: |
a9dd15da MD |
138 | default: |
139 | WARN_ON_ONCE(1); | |
140 | break; | |
141 | } | |
142 | break; | |
143 | } | |
144 | case atype_sequence: | |
3834b99f | 145 | case atype_sequence_bitfield: |
a9dd15da MD |
146 | { |
147 | struct lttng_basic_type *btype; | |
148 | ||
149 | btype = &type->u.sequence.length_type; | |
150 | switch (btype->atype) { | |
151 | case atype_integer: | |
152 | field_align = btype->u.basic.integer.alignment; | |
153 | break; | |
154 | ||
155 | case atype_string: | |
156 | case atype_array: | |
157 | case atype_sequence: | |
3834b99f MD |
158 | case atype_array_bitfield: |
159 | case atype_sequence_bitfield: | |
f513b2bf MD |
160 | case atype_struct: |
161 | case atype_array_compound: | |
162 | case atype_sequence_compound: | |
65c85aa6 | 163 | case atype_variant: |
a9dd15da MD |
164 | default: |
165 | WARN_ON_ONCE(1); | |
166 | break; | |
167 | } | |
168 | ||
169 | btype = &type->u.sequence.elem_type; | |
170 | switch (btype->atype) { | |
171 | case atype_integer: | |
172 | field_align = max_t(size_t, | |
173 | field_align, | |
174 | btype->u.basic.integer.alignment); | |
175 | break; | |
176 | ||
177 | case atype_string: | |
178 | break; | |
179 | ||
180 | case atype_array: | |
181 | case atype_sequence: | |
3834b99f MD |
182 | case atype_array_bitfield: |
183 | case atype_sequence_bitfield: | |
f513b2bf MD |
184 | case atype_struct: |
185 | case atype_array_compound: | |
186 | case atype_sequence_compound: | |
65c85aa6 | 187 | case atype_variant: |
a9dd15da MD |
188 | default: |
189 | WARN_ON_ONCE(1); | |
190 | break; | |
191 | } | |
192 | break; | |
193 | } | |
194 | case atype_string: | |
195 | break; | |
196 | ||
f513b2bf MD |
197 | case atype_struct: |
198 | case atype_array_compound: | |
199 | case atype_sequence_compound: | |
65c85aa6 | 200 | case atype_variant: |
f513b2bf MD |
201 | break; |
202 | ||
a9dd15da MD |
203 | case atype_enum: |
204 | default: | |
205 | WARN_ON_ONCE(1); | |
206 | break; | |
207 | } | |
208 | largest_align = max_t(size_t, largest_align, field_align); | |
209 | } | |
210 | ctx->largest_align = largest_align >> 3; /* bits to bytes */ | |
211 | } | |
212 | ||
4cae220c MD |
213 | /* |
214 | * Remove last context field. | |
215 | */ | |
8289661d MD |
216 | void lttng_remove_context_field(struct lttng_ctx **ctx_p, |
217 | struct lttng_ctx_field *field) | |
218 | { | |
219 | struct lttng_ctx *ctx; | |
220 | ||
221 | ctx = *ctx_p; | |
222 | ctx->nr_fields--; | |
4cae220c | 223 | WARN_ON_ONCE(&ctx->fields[ctx->nr_fields] != field); |
8289661d MD |
224 | memset(&ctx->fields[ctx->nr_fields], 0, sizeof(struct lttng_ctx_field)); |
225 | } | |
226 | EXPORT_SYMBOL_GPL(lttng_remove_context_field); | |
227 | ||
2dccf128 MD |
228 | void lttng_destroy_context(struct lttng_ctx *ctx) |
229 | { | |
230 | int i; | |
231 | ||
8070f5c0 MD |
232 | if (!ctx) |
233 | return; | |
9e7e4892 MD |
234 | for (i = 0; i < ctx->nr_fields; i++) { |
235 | if (ctx->fields[i].destroy) | |
236 | ctx->fields[i].destroy(&ctx->fields[i]); | |
237 | } | |
48f5e0b5 | 238 | lttng_kvfree(ctx->fields); |
2dccf128 MD |
239 | kfree(ctx); |
240 | } | |
07dfc1d0 MD |
241 | |
242 | int lttng_context_init(void) | |
243 | { | |
244 | int ret; | |
245 | ||
f127e61e MD |
246 | ret = lttng_add_hostname_to_ctx(<tng_static_ctx); |
247 | if (ret) { | |
38c4a82c | 248 | printk(KERN_WARNING "Cannot add context lttng_add_hostname_to_ctx"); |
f127e61e MD |
249 | } |
250 | ret = lttng_add_nice_to_ctx(<tng_static_ctx); | |
07dfc1d0 | 251 | if (ret) { |
38c4a82c | 252 | printk(KERN_WARNING "Cannot add context lttng_add_nice_to_ctx"); |
07dfc1d0 | 253 | } |
07dfc1d0 MD |
254 | ret = lttng_add_pid_to_ctx(<tng_static_ctx); |
255 | if (ret) { | |
38c4a82c | 256 | printk(KERN_WARNING "Cannot add context lttng_add_pid_to_ctx"); |
07dfc1d0 | 257 | } |
f127e61e | 258 | ret = lttng_add_ppid_to_ctx(<tng_static_ctx); |
07dfc1d0 | 259 | if (ret) { |
38c4a82c | 260 | printk(KERN_WARNING "Cannot add context lttng_add_ppid_to_ctx"); |
07dfc1d0 MD |
261 | } |
262 | ret = lttng_add_prio_to_ctx(<tng_static_ctx); | |
263 | if (ret) { | |
38c4a82c | 264 | printk(KERN_WARNING "Cannot add context lttng_add_prio_to_ctx"); |
07dfc1d0 | 265 | } |
f127e61e | 266 | ret = lttng_add_procname_to_ctx(<tng_static_ctx); |
07dfc1d0 | 267 | if (ret) { |
38c4a82c | 268 | printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx"); |
07dfc1d0 MD |
269 | } |
270 | ret = lttng_add_tid_to_ctx(<tng_static_ctx); | |
271 | if (ret) { | |
38c4a82c | 272 | printk(KERN_WARNING "Cannot add context lttng_add_tid_to_ctx"); |
07dfc1d0 | 273 | } |
f127e61e | 274 | ret = lttng_add_vppid_to_ctx(<tng_static_ctx); |
07dfc1d0 | 275 | if (ret) { |
38c4a82c | 276 | printk(KERN_WARNING "Cannot add context lttng_add_vppid_to_ctx"); |
07dfc1d0 | 277 | } |
f127e61e | 278 | ret = lttng_add_vtid_to_ctx(<tng_static_ctx); |
07dfc1d0 | 279 | if (ret) { |
38c4a82c | 280 | printk(KERN_WARNING "Cannot add context lttng_add_vtid_to_ctx"); |
07dfc1d0 | 281 | } |
f127e61e | 282 | ret = lttng_add_vpid_to_ctx(<tng_static_ctx); |
07dfc1d0 | 283 | if (ret) { |
38c4a82c | 284 | printk(KERN_WARNING "Cannot add context lttng_add_vpid_to_ctx"); |
07dfc1d0 | 285 | } |
b3699d90 MD |
286 | ret = lttng_add_cpu_id_to_ctx(<tng_static_ctx); |
287 | if (ret) { | |
288 | printk(KERN_WARNING "Cannot add context lttng_add_cpu_id_to_ctx"); | |
289 | } | |
79150a49 JD |
290 | ret = lttng_add_interruptible_to_ctx(<tng_static_ctx); |
291 | if (ret) { | |
292 | printk(KERN_WARNING "Cannot add context lttng_add_interruptible_to_ctx"); | |
293 | } | |
294 | ret = lttng_add_need_reschedule_to_ctx(<tng_static_ctx); | |
295 | if (ret) { | |
296 | printk(KERN_WARNING "Cannot add context lttng_add_need_reschedule_to_ctx"); | |
297 | } | |
79150a49 | 298 | ret = lttng_add_preemptible_to_ctx(<tng_static_ctx); |
d0e59d6f | 299 | if (ret && ret != -ENOSYS) { |
79150a49 JD |
300 | printk(KERN_WARNING "Cannot add context lttng_add_preemptible_to_ctx"); |
301 | } | |
79150a49 | 302 | ret = lttng_add_migratable_to_ctx(<tng_static_ctx); |
d0e59d6f | 303 | if (ret && ret != -ENOSYS) { |
79150a49 JD |
304 | printk(KERN_WARNING "Cannot add context lttng_add_migratable_to_ctx"); |
305 | } | |
a6cf40a4 MJ |
306 | ret = lttng_add_cgroup_ns_to_ctx(<tng_static_ctx); |
307 | if (ret && ret != -ENOSYS) { | |
308 | printk(KERN_WARNING "Cannot add context lttng_add_cgroup_ns_to_ctx"); | |
309 | } | |
310 | ret = lttng_add_ipc_ns_to_ctx(<tng_static_ctx); | |
311 | if (ret && ret != -ENOSYS) { | |
312 | printk(KERN_WARNING "Cannot add context lttng_add_ipc_ns_to_ctx"); | |
313 | } | |
314 | ret = lttng_add_mnt_ns_to_ctx(<tng_static_ctx); | |
315 | if (ret && ret != -ENOSYS) { | |
316 | printk(KERN_WARNING "Cannot add context lttng_add_mnt_ns_to_ctx"); | |
317 | } | |
318 | ret = lttng_add_net_ns_to_ctx(<tng_static_ctx); | |
319 | if (ret && ret != -ENOSYS) { | |
320 | printk(KERN_WARNING "Cannot add context lttng_add_net_ns_to_ctx"); | |
321 | } | |
322 | ret = lttng_add_pid_ns_to_ctx(<tng_static_ctx); | |
323 | if (ret && ret != -ENOSYS) { | |
324 | printk(KERN_WARNING "Cannot add context lttng_add_pid_ns_to_ctx"); | |
325 | } | |
326 | ret = lttng_add_user_ns_to_ctx(<tng_static_ctx); | |
327 | if (ret && ret != -ENOSYS) { | |
328 | printk(KERN_WARNING "Cannot add context lttng_add_user_ns_to_ctx"); | |
329 | } | |
330 | ret = lttng_add_uts_ns_to_ctx(<tng_static_ctx); | |
331 | if (ret && ret != -ENOSYS) { | |
332 | printk(KERN_WARNING "Cannot add context lttng_add_uts_ns_to_ctx"); | |
333 | } | |
f127e61e | 334 | /* TODO: perf counters for filtering */ |
07dfc1d0 MD |
335 | return 0; |
336 | } | |
337 | ||
338 | void lttng_context_exit(void) | |
339 | { | |
340 | lttng_destroy_context(lttng_static_ctx); | |
341 | lttng_static_ctx = NULL; | |
342 | } |