Commit | Line | Data |
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7514523f | 1 | /* |
3d084699 | 2 | * ltt-ring-buffer-client.h |
7514523f MD |
3 | * |
4 | * Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
3d084699 | 6 | * LTTng lib ring buffer client template. |
7514523f MD |
7 | * |
8 | * Dual LGPL v2.1/GPL v2 license. | |
9 | */ | |
10 | ||
11 | #include <linux/module.h> | |
c0e31d2e MD |
12 | #include <linux/types.h> |
13 | #include <linux/trace-clock.h> | |
14 | #include "ltt-events.h" | |
7514523f MD |
15 | #include "ltt-tracer.h" |
16 | ||
7514523f MD |
17 | static const struct lib_ring_buffer_config client_config; |
18 | ||
19 | static u64 client_ring_buffer_clock_read(struct channel *chan) | |
20 | { | |
21 | return lib_ring_buffer_clock_read(chan); | |
22 | } | |
23 | ||
1e2015dc | 24 | static |
7514523f MD |
25 | size_t client_record_header_size(const struct lib_ring_buffer_config *config, |
26 | struct channel *chan, size_t offset, | |
27 | size_t data_size, | |
28 | size_t *pre_header_padding, | |
29 | unsigned int rflags, | |
30 | struct lib_ring_buffer_ctx *ctx) | |
31 | { | |
32 | return record_header_size(config, chan, offset, data_size, | |
33 | pre_header_padding, rflags, ctx); | |
34 | } | |
35 | ||
36 | /** | |
1c25284c | 37 | * client_packet_header_size - called on buffer-switch to a new sub-buffer |
7514523f MD |
38 | * |
39 | * Return header size without padding after the structure. Don't use packed | |
40 | * structure because gcc generates inefficient code on some architectures | |
41 | * (powerpc, mips..) | |
42 | */ | |
1c25284c | 43 | static size_t client_packet_header_size(void) |
7514523f | 44 | { |
1c25284c | 45 | return offsetof(struct packet_header, header_end); |
7514523f MD |
46 | } |
47 | ||
48 | static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc, | |
49 | unsigned int subbuf_idx) | |
50 | { | |
51 | struct channel *chan = buf->backend.chan; | |
1c25284c MD |
52 | struct packet_header *header = |
53 | (struct packet_header *) | |
7514523f MD |
54 | lib_ring_buffer_offset_address(&buf->backend, |
55 | subbuf_idx * chan->backend.subbuf_size); | |
56 | ||
1c25284c MD |
57 | header->timestamp_begin = tsc; |
58 | header->content_size = 0xFFFFFFFF; /* for debugging */ | |
59 | write_trace_header(&client_config, header); | |
7514523f MD |
60 | } |
61 | ||
62 | /* | |
63 | * offset is assumed to never be 0 here : never deliver a completely empty | |
64 | * subbuffer. data_size is between 1 and subbuf_size. | |
65 | */ | |
66 | static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc, | |
67 | unsigned int subbuf_idx, unsigned long data_size) | |
68 | { | |
69 | struct channel *chan = buf->backend.chan; | |
1c25284c MD |
70 | struct packet_header *header = |
71 | (struct packet_header *) | |
7514523f MD |
72 | lib_ring_buffer_offset_address(&buf->backend, |
73 | subbuf_idx * chan->backend.subbuf_size); | |
74 | unsigned long records_lost = 0; | |
75 | ||
1c25284c MD |
76 | header->content_size = data_size; |
77 | header->packet_size = PAGE_ALIGN(data_size); | |
78 | header->timestamp_end = tsc; | |
7514523f MD |
79 | records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf); |
80 | records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf); | |
81 | records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf); | |
82 | header->events_lost = records_lost; | |
7514523f MD |
83 | } |
84 | ||
85 | static int client_buffer_create(struct lib_ring_buffer *buf, void *priv, | |
86 | int cpu, const char *name) | |
87 | { | |
1c25284c | 88 | return 0; |
7514523f MD |
89 | } |
90 | ||
91 | static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu) | |
92 | { | |
7514523f MD |
93 | } |
94 | ||
95 | static const struct lib_ring_buffer_config client_config = { | |
96 | .cb.ring_buffer_clock_read = client_ring_buffer_clock_read, | |
97 | .cb.record_header_size = client_record_header_size, | |
1c25284c | 98 | .cb.subbuffer_header_size = client_packet_header_size, |
7514523f MD |
99 | .cb.buffer_begin = client_buffer_begin, |
100 | .cb.buffer_end = client_buffer_end, | |
101 | .cb.buffer_create = client_buffer_create, | |
102 | .cb.buffer_finalize = client_buffer_finalize, | |
103 | ||
104 | .tsc_bits = 32, | |
105 | .alloc = RING_BUFFER_ALLOC_PER_CPU, | |
106 | .sync = RING_BUFFER_SYNC_PER_CPU, | |
3d084699 | 107 | .mode = RING_BUFFER_MODE_TEMPLATE, |
7514523f MD |
108 | #ifdef RING_BUFFER_ALIGN |
109 | .align = RING_BUFFER_NATURAL, | |
110 | #else | |
111 | .align = RING_BUFFER_PACKED, | |
112 | #endif | |
113 | .backend = RING_BUFFER_PAGE, | |
114 | .output = RING_BUFFER_SPLICE, | |
115 | .oops = RING_BUFFER_OOPS_CONSISTENCY, | |
116 | .ipi = RING_BUFFER_IPI_BARRIER, | |
117 | .wakeup = RING_BUFFER_WAKEUP_BY_TIMER, | |
118 | }; | |
119 | ||
1e2015dc | 120 | static |
1c25284c MD |
121 | struct channel *_channel_create(const char *name, |
122 | struct ltt_session *session, void *buf_addr, | |
123 | size_t subbuf_size, size_t num_subbuf, | |
124 | unsigned int switch_timer_interval, | |
125 | unsigned int read_timer_interval) | |
7514523f | 126 | { |
1c25284c | 127 | return channel_create(&client_config, name, session, buf_addr, |
7514523f MD |
128 | subbuf_size, num_subbuf, switch_timer_interval, |
129 | read_timer_interval); | |
7514523f MD |
130 | } |
131 | ||
1e2015dc | 132 | static |
7514523f MD |
133 | void ltt_channel_destroy(struct channel *chan) |
134 | { | |
7514523f | 135 | channel_destroy(chan); |
7514523f MD |
136 | } |
137 | ||
ad1c05e1 MD |
138 | static |
139 | struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan) | |
140 | { | |
141 | struct lib_ring_buffer *buf; | |
142 | int cpu; | |
143 | ||
1c25284c MD |
144 | for_each_channel_cpu(cpu, chan) { |
145 | buf = channel_get_ring_buffer(&client_config, chan, cpu); | |
ad1c05e1 MD |
146 | if (!lib_ring_buffer_open_read(buf)) |
147 | return buf; | |
148 | } | |
149 | return NULL; | |
150 | } | |
151 | ||
152 | static | |
1c25284c | 153 | void ltt_buffer_read_close(struct lib_ring_buffer *buf) |
ad1c05e1 MD |
154 | { |
155 | lib_ring_buffer_release_read(buf); | |
1c25284c MD |
156 | |
157 | } | |
158 | ||
159 | int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx) | |
160 | { | |
161 | int ret, cpu; | |
162 | ||
163 | cpu = lib_ring_buffer_get_cpu(&client_config); | |
164 | if (cpu < 0) | |
165 | return -EPERM; | |
166 | ctx->cpu = cpu; | |
167 | ||
168 | ret = lib_ring_buffer_reserve(&client_config, ctx); | |
169 | if (ret) | |
170 | goto put; | |
171 | return ret; | |
172 | ||
173 | put: | |
174 | lib_ring_buffer_put_cpu(&client_config); | |
175 | return ret; | |
ad1c05e1 MD |
176 | } |
177 | ||
1c25284c MD |
178 | void ltt_event_commit(struct lib_ring_buffer_ctx *ctx) |
179 | { | |
180 | lib_ring_buffer_commit(&client_config, ctx); | |
181 | lib_ring_buffer_put_cpu(&client_config); | |
182 | } | |
183 | ||
184 | ||
7514523f | 185 | static struct ltt_transport ltt_relay_transport = { |
3d084699 | 186 | .name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING, |
7514523f MD |
187 | .owner = THIS_MODULE, |
188 | .ops = { | |
1c25284c MD |
189 | .channel_create = _channel_create, |
190 | .channel_destroy = ltt_channel_destroy, | |
ad1c05e1 MD |
191 | .buffer_read_open = ltt_buffer_read_open, |
192 | .buffer_read_close = ltt_buffer_read_close, | |
1c25284c MD |
193 | .event_reserve = ltt_event_reserve, |
194 | .event_commit = ltt_event_commit, | |
7514523f MD |
195 | }, |
196 | }; | |
197 | ||
3d084699 | 198 | static int __init ltt_ring_buffer_client_init(void) |
7514523f MD |
199 | { |
200 | printk(KERN_INFO "LTT : ltt ring buffer client init\n"); | |
201 | ltt_transport_register(<t_relay_transport); | |
202 | return 0; | |
203 | } | |
204 | ||
1c25284c MD |
205 | module_init(ltt_ring_buffer_client_init); |
206 | ||
3d084699 | 207 | static void __exit ltt_ring_buffer_client_exit(void) |
7514523f MD |
208 | { |
209 | printk(KERN_INFO "LTT : ltt ring buffer client exit\n"); | |
210 | ltt_transport_unregister(<t_relay_transport); | |
211 | } | |
212 | ||
1c25284c MD |
213 | module_exit(ltt_ring_buffer_client_exit); |
214 | ||
7514523f MD |
215 | MODULE_LICENSE("GPL and additional rights"); |
216 | MODULE_AUTHOR("Mathieu Desnoyers"); | |
3d084699 MD |
217 | MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING |
218 | " client"); |