Commit | Line | Data |
---|---|---|
881833e3 MD |
1 | /* |
2 | * ltt-ring-buffer-client.h | |
3 | * | |
4 | * Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * LTTng lib ring buffer client template. | |
7 | * | |
8 | * Dual LGPL v2.1/GPL v2 license. | |
9 | */ | |
10 | ||
11 | #include <linux/module.h> | |
12 | #include <linux/types.h> | |
13 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ | |
14 | #include "ltt-events.h" | |
15 | #include "ltt-tracer.h" | |
16 | ||
881833e3 MD |
17 | struct metadata_packet_header { |
18 | uint32_t magic; /* 0x75D11D57 */ | |
1ec3f75a | 19 | uint8_t uuid[16]; /* Unique Universal Identifier */ |
881833e3 MD |
20 | uint32_t checksum; /* 0 if unused */ |
21 | uint32_t content_size; /* in bits */ | |
22 | uint32_t packet_size; /* in bits */ | |
23 | uint8_t compression_scheme; /* 0 if unused */ | |
24 | uint8_t encryption_scheme; /* 0 if unused */ | |
25 | uint8_t checksum_scheme; /* 0 if unused */ | |
26 | uint8_t header_end[0]; | |
27 | }; | |
28 | ||
29 | struct metadata_record_header { | |
30 | uint8_t header_end[0]; /* End of header */ | |
31 | }; | |
32 | ||
33 | static const struct lib_ring_buffer_config client_config; | |
34 | ||
35 | static inline | |
36 | u64 lib_ring_buffer_clock_read(struct channel *chan) | |
37 | { | |
38 | return 0; | |
39 | } | |
40 | ||
41 | static inline | |
42 | unsigned char record_header_size(const struct lib_ring_buffer_config *config, | |
43 | struct channel *chan, size_t offset, | |
64c796d8 | 44 | size_t *pre_header_padding, |
881833e3 MD |
45 | struct lib_ring_buffer_ctx *ctx) |
46 | { | |
47 | return 0; | |
48 | } | |
49 | ||
50 | #include "wrapper/ringbuffer/api.h" | |
51 | ||
52 | static u64 client_ring_buffer_clock_read(struct channel *chan) | |
53 | { | |
54 | return 0; | |
55 | } | |
56 | ||
57 | static | |
58 | size_t client_record_header_size(const struct lib_ring_buffer_config *config, | |
59 | struct channel *chan, size_t offset, | |
881833e3 | 60 | size_t *pre_header_padding, |
881833e3 MD |
61 | struct lib_ring_buffer_ctx *ctx) |
62 | { | |
63 | return 0; | |
64 | } | |
65 | ||
66 | /** | |
67 | * client_packet_header_size - called on buffer-switch to a new sub-buffer | |
68 | * | |
69 | * Return header size without padding after the structure. Don't use packed | |
70 | * structure because gcc generates inefficient code on some architectures | |
71 | * (powerpc, mips..) | |
72 | */ | |
73 | static size_t client_packet_header_size(void) | |
74 | { | |
75 | return offsetof(struct metadata_packet_header, header_end); | |
76 | } | |
77 | ||
78 | static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc, | |
79 | unsigned int subbuf_idx) | |
80 | { | |
81 | struct channel *chan = buf->backend.chan; | |
82 | struct metadata_packet_header *header = | |
83 | (struct metadata_packet_header *) | |
84 | lib_ring_buffer_offset_address(&buf->backend, | |
85 | subbuf_idx * chan->backend.subbuf_size); | |
9115fbdc MD |
86 | struct ltt_channel *ltt_chan = channel_get_private(chan); |
87 | struct ltt_session *session = ltt_chan->session; | |
881833e3 MD |
88 | |
89 | header->magic = TSDL_MAGIC_NUMBER; | |
1ec3f75a | 90 | memcpy(header->uuid, session->uuid.b, sizeof(session->uuid)); |
881833e3 MD |
91 | header->checksum = 0; /* 0 if unused */ |
92 | header->content_size = 0xFFFFFFFF; /* in bits, for debugging */ | |
93 | header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */ | |
94 | header->compression_scheme = 0; /* 0 if unused */ | |
95 | header->encryption_scheme = 0; /* 0 if unused */ | |
96 | header->checksum_scheme = 0; /* 0 if unused */ | |
97 | } | |
98 | ||
99 | /* | |
100 | * offset is assumed to never be 0 here : never deliver a completely empty | |
101 | * subbuffer. data_size is between 1 and subbuf_size. | |
102 | */ | |
103 | static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc, | |
104 | unsigned int subbuf_idx, unsigned long data_size) | |
105 | { | |
106 | struct channel *chan = buf->backend.chan; | |
d793d5e1 | 107 | struct metadata_packet_header *header = |
1ec3f75a | 108 | (struct metadata_packet_header *) |
881833e3 MD |
109 | lib_ring_buffer_offset_address(&buf->backend, |
110 | subbuf_idx * chan->backend.subbuf_size); | |
111 | unsigned long records_lost = 0; | |
112 | ||
113 | header->content_size = data_size * CHAR_BIT; /* in bits */ | |
114 | header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */ | |
115 | records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf); | |
116 | records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf); | |
117 | records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf); | |
118 | WARN_ON_ONCE(records_lost != 0); | |
119 | } | |
120 | ||
121 | static int client_buffer_create(struct lib_ring_buffer *buf, void *priv, | |
122 | int cpu, const char *name) | |
123 | { | |
124 | return 0; | |
125 | } | |
126 | ||
127 | static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu) | |
128 | { | |
129 | } | |
130 | ||
131 | static const struct lib_ring_buffer_config client_config = { | |
132 | .cb.ring_buffer_clock_read = client_ring_buffer_clock_read, | |
133 | .cb.record_header_size = client_record_header_size, | |
134 | .cb.subbuffer_header_size = client_packet_header_size, | |
135 | .cb.buffer_begin = client_buffer_begin, | |
136 | .cb.buffer_end = client_buffer_end, | |
137 | .cb.buffer_create = client_buffer_create, | |
138 | .cb.buffer_finalize = client_buffer_finalize, | |
139 | ||
140 | .tsc_bits = 0, | |
141 | .alloc = RING_BUFFER_ALLOC_GLOBAL, | |
142 | .sync = RING_BUFFER_SYNC_GLOBAL, | |
143 | .mode = RING_BUFFER_MODE_TEMPLATE, | |
144 | .backend = RING_BUFFER_PAGE, | |
145 | .output = RING_BUFFER_SPLICE, | |
146 | .oops = RING_BUFFER_OOPS_CONSISTENCY, | |
147 | .ipi = RING_BUFFER_IPI_BARRIER, | |
148 | .wakeup = RING_BUFFER_WAKEUP_BY_TIMER, | |
149 | }; | |
150 | ||
151 | static | |
152 | struct channel *_channel_create(const char *name, | |
89fff18e | 153 | struct ltt_channel *ltt_chan, void *buf_addr, |
881833e3 MD |
154 | size_t subbuf_size, size_t num_subbuf, |
155 | unsigned int switch_timer_interval, | |
156 | unsigned int read_timer_interval) | |
157 | { | |
89fff18e | 158 | return channel_create(&client_config, name, ltt_chan, buf_addr, |
881833e3 MD |
159 | subbuf_size, num_subbuf, switch_timer_interval, |
160 | read_timer_interval); | |
161 | } | |
162 | ||
163 | static | |
164 | void ltt_channel_destroy(struct channel *chan) | |
165 | { | |
166 | channel_destroy(chan); | |
167 | } | |
168 | ||
169 | static | |
170 | struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan) | |
171 | { | |
172 | struct lib_ring_buffer *buf; | |
881833e3 | 173 | |
cd4bd11f MD |
174 | buf = channel_get_ring_buffer(&client_config, chan, 0); |
175 | if (!lib_ring_buffer_open_read(buf)) | |
176 | return buf; | |
881833e3 MD |
177 | return NULL; |
178 | } | |
179 | ||
180 | static | |
181 | void ltt_buffer_read_close(struct lib_ring_buffer *buf) | |
182 | { | |
183 | lib_ring_buffer_release_read(buf); | |
881833e3 MD |
184 | } |
185 | ||
c099397a | 186 | static |
64c796d8 | 187 | int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id) |
881833e3 MD |
188 | { |
189 | return lib_ring_buffer_reserve(&client_config, ctx); | |
190 | } | |
191 | ||
c099397a | 192 | static |
881833e3 MD |
193 | void ltt_event_commit(struct lib_ring_buffer_ctx *ctx) |
194 | { | |
195 | lib_ring_buffer_commit(&client_config, ctx); | |
196 | } | |
197 | ||
c099397a | 198 | static |
881833e3 MD |
199 | void ltt_event_write(struct lib_ring_buffer_ctx *ctx, const void *src, |
200 | size_t len) | |
201 | { | |
202 | lib_ring_buffer_write(&client_config, ctx, src, len); | |
203 | } | |
204 | ||
1ec3f75a MD |
205 | static |
206 | size_t ltt_packet_avail_size(struct channel *chan) | |
207 | ||
208 | { | |
209 | unsigned long o_begin; | |
210 | struct lib_ring_buffer *buf; | |
211 | ||
212 | buf = chan->backend.buf; /* Only for global buffer ! */ | |
213 | o_begin = v_read(&client_config, &buf->offset); | |
214 | if (subbuf_offset(o_begin, chan) != 0) { | |
215 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan); | |
216 | } else { | |
217 | return chan->backend.subbuf_size - subbuf_offset(o_begin, chan) | |
218 | - sizeof(struct metadata_packet_header); | |
219 | } | |
220 | } | |
221 | ||
c099397a | 222 | static |
24cedcfe | 223 | wait_queue_head_t *ltt_get_reader_wait_queue(struct channel *chan) |
c099397a | 224 | { |
24cedcfe MD |
225 | return &chan->read_wait; |
226 | } | |
227 | ||
228 | static | |
229 | wait_queue_head_t *ltt_get_hp_wait_queue(struct channel *chan) | |
230 | { | |
231 | return &chan->hp_wait; | |
232 | } | |
233 | ||
234 | static | |
235 | int ltt_is_finalized(struct channel *chan) | |
236 | { | |
237 | return lib_ring_buffer_channel_is_finalized(chan); | |
c099397a MD |
238 | } |
239 | ||
254ec7bc MD |
240 | static |
241 | int ltt_is_disabled(struct channel *chan) | |
242 | { | |
243 | return lib_ring_buffer_channel_is_disabled(chan); | |
244 | } | |
245 | ||
881833e3 MD |
246 | static struct ltt_transport ltt_relay_transport = { |
247 | .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING, | |
248 | .owner = THIS_MODULE, | |
249 | .ops = { | |
250 | .channel_create = _channel_create, | |
251 | .channel_destroy = ltt_channel_destroy, | |
252 | .buffer_read_open = ltt_buffer_read_open, | |
253 | .buffer_read_close = ltt_buffer_read_close, | |
254 | .event_reserve = ltt_event_reserve, | |
255 | .event_commit = ltt_event_commit, | |
256 | .event_write = ltt_event_write, | |
1ec3f75a | 257 | .packet_avail_size = ltt_packet_avail_size, |
c099397a | 258 | .get_reader_wait_queue = ltt_get_reader_wait_queue, |
24cedcfe MD |
259 | .get_hp_wait_queue = ltt_get_hp_wait_queue, |
260 | .is_finalized = ltt_is_finalized, | |
254ec7bc | 261 | .is_disabled = ltt_is_disabled, |
881833e3 MD |
262 | }, |
263 | }; | |
264 | ||
265 | static int __init ltt_ring_buffer_client_init(void) | |
266 | { | |
267 | /* | |
268 | * This vmalloc sync all also takes care of the lib ring buffer | |
269 | * vmalloc'd module pages when it is built as a module into LTTng. | |
270 | */ | |
271 | wrapper_vmalloc_sync_all(); | |
272 | printk(KERN_INFO "LTT : ltt ring buffer metadata client init\n"); | |
273 | ltt_transport_register(<t_relay_transport); | |
274 | return 0; | |
275 | } | |
276 | ||
277 | module_init(ltt_ring_buffer_client_init); | |
278 | ||
279 | static void __exit ltt_ring_buffer_client_exit(void) | |
280 | { | |
281 | printk(KERN_INFO "LTT : ltt ring buffer metadata client exit\n"); | |
282 | ltt_transport_unregister(<t_relay_transport); | |
283 | } | |
284 | ||
285 | module_exit(ltt_ring_buffer_client_exit); | |
286 | ||
287 | MODULE_LICENSE("GPL and additional rights"); | |
288 | MODULE_AUTHOR("Mathieu Desnoyers"); | |
289 | MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING | |
290 | " client"); |