2 * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
3 * Copyright (C) 2009 Pierre-Marc Fournier
5 * This contains the definitions for the Linux Trace Toolkit tracer.
7 * Ported to userspace by Pierre-Marc Fournier.
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include <sys/types.h>
29 #include <ust/marker.h>
30 #include <ust/marker-internal.h>
31 #include <ust/probe.h>
34 #include "tracercore.h"
35 #include "tracerconst.h"
38 /* Number of bytes to log with a read/write event */
39 #define LTT_LOG_RW_SIZE 32L
41 /* Interval (in jiffies) at which the LTT per-CPU timer fires */
42 #define LTT_PERCPU_TIMER_INTERVAL 1
45 #define LTT_ARCH_TYPE LTT_ARCH_TYPE_UNDEFINED
48 #ifndef LTT_ARCH_VARIANT
49 #define LTT_ARCH_VARIANT LTT_ARCH_VARIANT_NONE
52 struct ltt_active_ust_marker
;
54 /* Maximum number of callbacks per ust_marker */
55 #define LTT_NR_CALLBACKS 10
57 struct ltt_serialize_closure
;
58 struct ltt_probe_private_data
;
60 struct ltt_serialize_closure
{
61 ltt_serialize_cb
*callbacks
;
62 long cb_args
[LTT_NR_CALLBACKS
];
66 extern size_t ltt_serialize_data(struct ust_buffer
*buf
, size_t buf_offset
,
67 struct ltt_serialize_closure
*closure
,
68 void *serialize_private
,
69 unsigned int stack_pos_ctx
, int *largest_align
,
70 const char *fmt
, va_list *args
);
72 struct ltt_probe_private_data
{
73 struct ust_trace
*trace
; /*
74 * Target trace, for metadata
77 ltt_serialize_cb serializer
; /*
78 * Serialization function override.
80 void *serialize_private
; /*
81 * Private data for serialization
91 struct chan_info_struct
{
93 unsigned int def_subbufsize
;
94 unsigned int def_subbufcount
;
97 struct ltt_active_ust_marker
{
98 struct cds_list_head node
; /* active markers list */
102 struct ltt_available_probe
*probe
;
105 struct ust_marker
; //ust//
106 extern void ltt_vtrace(const struct ust_marker
*mdata
, void *probe_data
,
107 void *call_data
, const char *fmt
, va_list *args
);
108 extern void ltt_trace(const struct ust_marker
*mdata
, void *probe_data
,
109 void *call_data
, const char *fmt
, ...);
112 * Unique ID assigned to each registered probe.
115 UST_MARKER_ID_SET_MARKER_ID
= 0, /* Static IDs available (range 0-7) */
116 UST_MARKER_ID_SET_MARKER_FORMAT
,
117 UST_MARKER_ID_COMPACT
, /* Compact IDs (range: 8-127) */
118 UST_MARKER_ID_DYNAMIC
, /* Dynamic IDs (range: 128-65535) */
121 /* static ids 0-1 reserved for internal use. */
122 #define UST_MARKER_CORE_IDS 2
123 static __inline__
enum ust_marker_id
ust_marker_id_type(uint16_t id
)
125 if (id
< UST_MARKER_CORE_IDS
)
126 return (enum ust_marker_id
)id
;
128 return UST_MARKER_ID_DYNAMIC
;
131 struct user_dbg_data
{
132 unsigned long avail_size
;
137 struct ltt_trace_ops
{
138 /* First 32 bytes cache-hot cacheline */
139 void (*wakeup_channel
) (struct ust_channel
*channel
);
140 int (*user_blocking
) (struct ust_trace
*trace
,
141 unsigned int index
, size_t data_size
,
142 struct user_dbg_data
*dbg
);
143 /* End of first 32 bytes cacheline */
144 int (*create_dirs
) (struct ust_trace
*new_trace
);
145 void (*remove_dirs
) (struct ust_trace
*new_trace
);
146 int (*create_channel
) (const char *trace_name
,
147 struct ust_trace
*trace
,
148 const char *channel_name
,
149 struct ust_channel
*channel
,
150 unsigned int subbuf_size
,
151 unsigned int n_subbufs
, int overwrite
);
152 void (*finish_channel
) (struct ust_channel
*channel
);
153 void (*remove_channel
) (struct ust_channel
*channel
);
154 void (*user_errors
) (struct ust_trace
*trace
,
155 unsigned int index
, size_t data_size
,
156 struct user_dbg_data
*dbg
, unsigned int cpu
);
159 struct ltt_transport
{
161 struct module
*owner
;
162 struct cds_list_head node
;
163 struct ltt_trace_ops ops
;
166 enum trace_mode
{ LTT_TRACE_NORMAL
, LTT_TRACE_FLIGHT
, LTT_TRACE_HYBRID
};
168 #define CHANNEL_FLAG_ENABLE (1U<<0)
169 #define CHANNEL_FLAG_OVERWRITE (1U<<1)
171 /* Per-trace information - each trace/flight recorder represented by one */
173 /* First 32 bytes cache-hot cacheline */
174 struct cds_list_head list
;
175 struct ltt_trace_ops
*ops
;
177 /* Second 32 bytes cache-hot cacheline */
178 struct ust_channel
*channels
;
179 unsigned int nr_channels
;
183 unsigned long long start_monotonic
;
184 struct timeval start_time
;
185 struct ltt_channel_setting
*settings
;
187 struct dentry
*trace_root
;
189 struct urcu_ref urcu_ref
; /* Each channel has a urcu_ref of the trace struct */
190 struct ltt_transport
*transport
;
191 struct urcu_ref ltt_transport_urcu_ref
;
192 char trace_name
[NAME_MAX
];
193 } ____cacheline_aligned
;
196 * We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
197 * specifically with CPU frequency scaling someday, so using an interpolation
198 * between the start and end of buffer values is not flexible enough. Using an
199 * immediate frequency value permits to calculate directly the times for parts
200 * of a buffer that would be before a frequency change.
202 * Keep the natural field alignment for _each field_ within this structure if
203 * you ever add/remove a field from this header. Packed attribute is not used
204 * because gcc generates poor code on at least powerpc and mips. Don't ever
205 * let gcc add padding between the structure elements.
207 struct ltt_subbuffer_header
{
208 uint64_t cycle_count_begin
; /* Cycle count at subbuffer start */
209 uint64_t cycle_count_end
; /* Cycle count at subbuffer end */
210 uint32_t magic_number
; /*
211 * Trace magic number.
212 * contains endianness information.
214 uint8_t major_version
;
215 uint8_t minor_version
;
216 uint8_t arch_size
; /* Architecture pointer size */
217 uint8_t alignment
; /* LTT data alignment */
218 uint64_t start_time_sec
; /* NTP-corrected start time */
219 uint64_t start_time_usec
;
220 uint64_t start_freq
; /*
221 * Frequency at trace start,
222 * used all along the trace.
224 uint32_t freq_scale
; /* Frequency scaling (divisor) */
225 uint32_t data_size
; /* Size of data in subbuffer */
226 uint32_t sb_size
; /* Subbuffer size (including padding) */
227 uint32_t events_lost
; /*
228 * Events lost in this subbuffer since
229 * the beginning of the trace.
232 uint32_t subbuf_corrupt
; /*
233 * Corrupted (lost) subbuffers since
234 * the begginig of the trace.
237 uint8_t header_end
[0]; /* End of header */
241 * ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
243 * Return header size without padding after the structure. Don't use packed
244 * structure because gcc generates inefficient code on some architectures
247 static __inline__
size_t ltt_subbuffer_header_size(void)
249 return offsetof(struct ltt_subbuffer_header
, header_end
);
252 extern size_t ltt_write_event_header_slow(struct ust_channel
*channel
,
253 struct ust_buffer
*buf
, long buf_offset
,
254 u16 eID
, u32 event_size
,
255 u64 tsc
, unsigned int rflags
);
259 * ltt_write_event_header
261 * Writes the event header to the offset (already aligned on 32-bits).
263 * @trace : trace to write to.
264 * @channel : pointer to the channel structure..
265 * @buf : buffer to write to.
266 * @buf_offset : buffer offset to write to (aligned on 32 bits).
268 * @event_size : size of the event, excluding the event header.
269 * @tsc : time stamp counter.
270 * @rflags : reservation flags.
272 * returns : offset where the event data must be written.
274 static __inline__
size_t ltt_write_event_header(struct ust_channel
*chan
,
275 struct ust_buffer
*buf
, long buf_offset
,
276 u16 eID
, u32 event_size
,
277 u64 tsc
, unsigned int rflags
)
279 struct ltt_event_header header
;
281 if (unlikely(rflags
))
284 header
.id_time
= eID
<< LTT_TSC_BITS
;
285 header
.id_time
|= (u32
)tsc
& LTT_TSC_MASK
;
286 ust_buffers_write(buf
, buf_offset
, &header
, sizeof(header
));
287 buf_offset
+= sizeof(header
);
292 return ltt_write_event_header_slow(chan
, buf
, buf_offset
,
293 eID
, event_size
, tsc
, rflags
);
306 #define LTT_METADATA_CHANNEL "metadata_state"
307 #define LTT_UST_CHANNEL "ust"
309 #define LTT_FLIGHT_PREFIX "flight-"
311 /* Tracer properties */
312 //#define LTT_DEFAULT_SUBBUF_SIZE_LOW 134217728
313 #define LTT_DEFAULT_SUBBUF_SIZE_LOW 65536
314 //#define LTT_DEFAULT_SUBBUF_SIZE_LOW 4096
315 #define LTT_DEFAULT_N_SUBBUFS_LOW 2
316 //#define LTT_DEFAULT_SUBBUF_SIZE_MED 134217728
317 #define LTT_DEFAULT_SUBBUF_SIZE_MED 262144
318 //#define LTT_DEFAULT_SUBBUF_SIZE_MED 4096
319 #define LTT_DEFAULT_N_SUBBUFS_MED 2
320 //#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 134217728
321 #define LTT_DEFAULT_SUBBUF_SIZE_HIGH 1048576
322 //#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 4096
323 #define LTT_DEFAULT_N_SUBBUFS_HIGH 2
324 #define LTT_TRACER_MAGIC_NUMBER 0x00D6B7ED
325 #define LTT_TRACER_VERSION_MAJOR 2
326 #define LTT_TRACER_VERSION_MINOR 6
329 * ust_write_trace_header - Write trace header
330 * @trace: Trace information
331 * @header: Memory address where the information must be written to
333 static __inline__
void ltt_write_trace_header(struct ust_trace
*trace
,
334 struct ltt_subbuffer_header
*header
)
336 header
->magic_number
= LTT_TRACER_MAGIC_NUMBER
;
337 header
->major_version
= LTT_TRACER_VERSION_MAJOR
;
338 header
->minor_version
= LTT_TRACER_VERSION_MINOR
;
339 header
->arch_size
= sizeof(void *);
340 header
->alignment
= ltt_get_alignment();
341 header
->start_time_sec
= trace
->start_time
.tv_sec
;
342 header
->start_time_usec
= trace
->start_time
.tv_usec
;
343 header
->start_freq
= trace
->start_freq
;
344 header
->freq_scale
= trace
->freq_scale
;
349 static __inline__
int ust_get_cpu(void)
353 cpu
= sched_getcpu();
354 if (likely(cpu
>= 0))
357 * If getcpu(2) is not implemented in the Kernel use CPU 0 as fallback.
362 #else /* #else #ifndef UST_VALGRIND */
364 static __inline__
int ust_get_cpu(void)
367 * Valgrind does not support the sched_getcpu() vsyscall.
368 * It causes it to detect a segfault in the program and stop it.
369 * So if we want to check libust with valgrind, we have to refrain
370 * from using this call. TODO: it would probably be better to return
371 * other values too, to better test it.
376 #endif /* #else #ifndef UST_VALGRIND */
379 * Size reserved for high priority events (interrupts, NMI, BH) at the end of a
380 * nearly full buffer. User space won't use this last amount of space when in
381 * blocking mode. This space also includes the event header that would be
382 * written by this user space event.
384 #define LTT_RESERVE_CRITICAL 4096
386 /* Register and unregister function pointers */
388 enum ltt_module_function
{
389 LTT_FUNCTION_RUN_FILTER
,
390 LTT_FUNCTION_FILTER_CONTROL
,
391 LTT_FUNCTION_STATEDUMP
394 extern void ltt_transport_register(struct ltt_transport
*transport
);
395 extern void ltt_transport_unregister(struct ltt_transport
*transport
);
397 /* Exported control function */
399 union ltt_control_args
{
401 enum trace_mode mode
;
402 unsigned int subbuf_size_low
;
403 unsigned int n_subbufs_low
;
404 unsigned int subbuf_size_med
;
405 unsigned int n_subbufs_med
;
406 unsigned int subbuf_size_high
;
407 unsigned int n_subbufs_high
;
411 extern int _ltt_trace_setup(const char *trace_name
);
412 extern int ltt_trace_setup(const char *trace_name
);
413 extern struct ust_trace
*_ltt_trace_find_setup(const char *trace_name
);
414 extern int ltt_trace_set_type(const char *trace_name
, const char *trace_type
);
415 extern int ltt_trace_set_channel_subbufsize(const char *trace_name
,
416 const char *channel_name
, unsigned int size
);
417 extern int ltt_trace_set_channel_subbufcount(const char *trace_name
,
418 const char *channel_name
, unsigned int cnt
);
419 extern int ltt_trace_set_channel_enable(const char *trace_name
,
420 const char *channel_name
, unsigned int enable
);
421 extern int ltt_trace_set_channel_overwrite(const char *trace_name
,
422 const char *channel_name
, unsigned int overwrite
);
423 extern int ltt_trace_alloc(const char *trace_name
);
424 extern int ltt_trace_destroy(const char *trace_name
, int drop
);
425 extern int ltt_trace_start(const char *trace_name
);
426 extern int ltt_trace_stop(const char *trace_name
);
428 enum ltt_filter_control_msg
{
429 LTT_FILTER_DEFAULT_ACCEPT
,
430 LTT_FILTER_DEFAULT_REJECT
433 extern int ltt_filter_control(enum ltt_filter_control_msg msg
,
434 const char *trace_name
);
436 extern struct dentry
*get_filter_root(void);
438 extern void ltt_write_trace_header(struct ust_trace
*trace
,
439 struct ltt_subbuffer_header
*header
);
440 extern void ltt_buffer_destroy(struct ust_channel
*ltt_chan
);
442 extern void ltt_core_register(int (*function
)(u8
, void *));
444 extern void ltt_core_unregister(void);
446 extern void ltt_release_trace(struct urcu_ref
*urcu_ref
);
447 extern void ltt_release_transport(struct urcu_ref
*urcu_ref
);
449 extern void ltt_dump_ust_marker_state(struct ust_trace
*trace
);
451 extern void ltt_lock_traces(void);
452 extern void ltt_unlock_traces(void);
454 extern struct ust_trace
*_ltt_trace_find(const char *trace_name
);
456 #endif /* _LTT_TRACER_H */