Commit | Line | Data |
---|---|---|
b64bc438 | 1 | /* |
886d51a3 | 2 | * lttng-context-vpid.c |
b64bc438 MD |
3 | * |
4 | * LTTng vPID context. | |
5 | * | |
886d51a3 MD |
6 | * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
b64bc438 MD |
21 | */ |
22 | ||
23 | #include <linux/module.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/sched.h> | |
241ae9a8 MD |
26 | #include <lttng-events.h> |
27 | #include <wrapper/ringbuffer/frontend_types.h> | |
28 | #include <wrapper/vmalloc.h> | |
29 | #include <lttng-tracer.h> | |
b64bc438 MD |
30 | |
31 | static | |
32 | size_t vpid_get_size(size_t offset) | |
33 | { | |
34 | size_t size = 0; | |
35 | ||
a90917c3 | 36 | size += lib_ring_buffer_align(offset, lttng_alignof(pid_t)); |
b64bc438 MD |
37 | size += sizeof(pid_t); |
38 | return size; | |
39 | } | |
40 | ||
41 | static | |
42 | void vpid_record(struct lttng_ctx_field *field, | |
43 | struct lib_ring_buffer_ctx *ctx, | |
a90917c3 | 44 | struct lttng_channel *chan) |
b64bc438 MD |
45 | { |
46 | pid_t vpid; | |
47 | ||
90f96adf MD |
48 | /* |
49 | * nsproxy can be NULL when scheduled out of exit. | |
50 | */ | |
51 | if (!current->nsproxy) | |
52 | vpid = 0; | |
53 | else | |
54 | vpid = task_tgid_vnr(current); | |
a90917c3 | 55 | lib_ring_buffer_align_ctx(ctx, lttng_alignof(vpid)); |
b64bc438 MD |
56 | chan->ops->event_write(ctx, &vpid, sizeof(vpid)); |
57 | } | |
58 | ||
07dfc1d0 MD |
59 | static |
60 | void vpid_get_value(struct lttng_ctx_field *field, | |
79150a49 | 61 | struct lttng_probe_ctx *lttng_probe_ctx, |
07dfc1d0 MD |
62 | union lttng_ctx_value *value) |
63 | { | |
64 | pid_t vpid; | |
65 | ||
66 | /* | |
67 | * nsproxy can be NULL when scheduled out of exit. | |
68 | */ | |
69 | if (!current->nsproxy) | |
70 | vpid = 0; | |
71 | else | |
72 | vpid = task_tgid_vnr(current); | |
73 | value->s64 = vpid; | |
74 | } | |
75 | ||
b64bc438 MD |
76 | int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx) |
77 | { | |
78 | struct lttng_ctx_field *field; | |
b64bc438 MD |
79 | |
80 | field = lttng_append_context(ctx); | |
81 | if (!field) | |
09fec6b4 | 82 | return -ENOMEM; |
44252f0f MD |
83 | if (lttng_find_context(*ctx, "vpid")) { |
84 | lttng_remove_context_field(ctx, field); | |
85 | return -EEXIST; | |
86 | } | |
b64bc438 MD |
87 | field->event_field.name = "vpid"; |
88 | field->event_field.type.atype = atype_integer; | |
89 | field->event_field.type.u.basic.integer.size = sizeof(pid_t) * CHAR_BIT; | |
a90917c3 | 90 | field->event_field.type.u.basic.integer.alignment = lttng_alignof(pid_t) * CHAR_BIT; |
06254b0f | 91 | field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(pid_t); |
b64bc438 MD |
92 | field->event_field.type.u.basic.integer.reverse_byte_order = 0; |
93 | field->event_field.type.u.basic.integer.base = 10; | |
94 | field->event_field.type.u.basic.integer.encoding = lttng_encode_none; | |
95 | field->get_size = vpid_get_size; | |
96 | field->record = vpid_record; | |
07dfc1d0 | 97 | field->get_value = vpid_get_value; |
a9dd15da | 98 | lttng_context_update(*ctx); |
b64bc438 MD |
99 | wrapper_vmalloc_sync_all(); |
100 | return 0; | |
101 | } | |
102 | EXPORT_SYMBOL_GPL(lttng_add_vpid_to_ctx); |