2 * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
4 * This contains the definitions for the Linux Trace Toolkit tracer.
10 //ust// #include <stdarg.h>
11 //ust// #include <linux/types.h>
12 //ust// #include <linux/limits.h>
13 //ust// #include <linux/list.h>
14 //ust// #include <linux/cache.h>
15 //ust// #include <linux/kernel.h>
16 //ust// #include <linux/timex.h>
17 //ust// #include <linux/wait.h>
18 //ust// #include <linux/ltt-relay.h>
19 //ust// #include <linux/ltt-channels.h>
20 //ust// #include <linux/ltt-core.h>
21 //ust// #include <linux/marker.h>
22 //ust// #include <linux/trace-clock.h>
23 //ust// #include <asm/atomic.h>
24 //ust// #include <asm/local.h>
25 #include <sys/types.h>
29 #include "kernelcompat.h"
32 /* Number of bytes to log with a read/write event */
33 #define LTT_LOG_RW_SIZE 32L
35 /* Interval (in jiffies) at which the LTT per-CPU timer fires */
36 #define LTT_PERCPU_TIMER_INTERVAL 1
39 #define LTT_ARCH_TYPE LTT_ARCH_TYPE_UNDEFINED
42 #ifndef LTT_ARCH_VARIANT
43 #define LTT_ARCH_VARIANT LTT_ARCH_VARIANT_NONE
46 struct ltt_active_marker
;
48 /* Maximum number of callbacks per marker */
49 #define LTT_NR_CALLBACKS 10
51 struct ltt_serialize_closure
;
52 struct ltt_probe_private_data
;
54 /* Serialization callback '%k' */
55 typedef size_t (*ltt_serialize_cb
)(struct rchan_buf
*buf
, size_t buf_offset
,
56 struct ltt_serialize_closure
*closure
,
57 void *serialize_private
, int *largest_align
,
58 const char *fmt
, va_list *args
);
60 struct ltt_serialize_closure
{
61 ltt_serialize_cb
*callbacks
;
62 long cb_args
[LTT_NR_CALLBACKS
];
66 size_t ltt_serialize_data(struct rchan_buf
*buf
, size_t buf_offset
,
67 struct ltt_serialize_closure
*closure
,
68 void *serialize_private
,
69 int *largest_align
, const char *fmt
, va_list *args
);
71 //ust// struct ltt_available_probe {
72 //ust// const char *name; /* probe name */
73 //ust// const char *format;
74 //ust// marker_probe_func *probe_func;
75 //ust// ltt_serialize_cb callbacks[LTT_NR_CALLBACKS];
76 //ust// struct list_head node; /* registered probes list */
79 struct ltt_probe_private_data
{
80 struct ltt_trace_struct
*trace
; /*
81 * Target trace, for metadata
84 ltt_serialize_cb serializer
; /*
85 * Serialization function override.
87 void *serialize_private
; /*
88 * Private data for serialization
98 struct ltt_active_marker
{
99 struct list_head node
; /* active markers list */
103 struct ltt_available_probe
*probe
;
106 struct marker
; //ust//
107 extern void ltt_vtrace(const struct marker
*mdata
, void *probe_data
,
108 void *call_data
, const char *fmt
, va_list *args
);
109 extern void ltt_trace(const struct marker
*mdata
, void *probe_data
,
110 void *call_data
, const char *fmt
, ...);
113 * Unique ID assigned to each registered probe.
116 MARKER_ID_SET_MARKER_ID
= 0, /* Static IDs available (range 0-7) */
117 MARKER_ID_SET_MARKER_FORMAT
,
118 MARKER_ID_COMPACT
, /* Compact IDs (range: 8-127) */
119 MARKER_ID_DYNAMIC
, /* Dynamic IDs (range: 128-65535) */
122 /* static ids 0-1 reserved for internal use. */
123 #define MARKER_CORE_IDS 2
124 static inline enum marker_id
marker_id_type(uint16_t id
)
126 if (id
< MARKER_CORE_IDS
)
127 return (enum marker_id
)id
;
129 return MARKER_ID_DYNAMIC
;
132 //ust// #ifdef CONFIG_LTT
134 struct user_dbg_data
{
135 unsigned long avail_size
;
140 struct ltt_trace_ops
{
141 /* First 32 bytes cache-hot cacheline */
142 int (*reserve_slot
) (struct ltt_trace_struct
*trace
,
143 struct ltt_channel_struct
*channel
,
144 void **transport_data
, size_t data_size
,
145 size_t *slot_size
, long *buf_offset
, u64
*tsc
,
146 unsigned int *rflags
,
149 void (*commit_slot
) (struct ltt_channel_struct
*channel
,
150 void **transport_data
, long buf_offset
,
152 void (*wakeup_channel
) (struct ltt_channel_struct
*ltt_channel
);
153 int (*user_blocking
) (struct ltt_trace_struct
*trace
,
154 unsigned int index
, size_t data_size
,
155 struct user_dbg_data
*dbg
);
156 //ust// /* End of first 32 bytes cacheline */
157 //ust// int (*create_dirs) (struct ltt_trace_struct *new_trace);
158 //ust// void (*remove_dirs) (struct ltt_trace_struct *new_trace);
159 int (*create_channel
) (const char *trace_name
,
160 struct ltt_trace_struct
*trace
,
161 struct dentry
*dir
, const char *channel_name
,
162 struct ltt_channel_struct
*ltt_chan
,
163 unsigned int subbuf_size
,
164 unsigned int n_subbufs
, int overwrite
);
165 void (*finish_channel
) (struct ltt_channel_struct
*channel
);
166 void (*remove_channel
) (struct ltt_channel_struct
*channel
);
167 void (*user_errors
) (struct ltt_trace_struct
*trace
,
168 unsigned int index
, size_t data_size
,
169 struct user_dbg_data
*dbg
, int cpu
);
170 //ust// #ifdef CONFIG_HOTPLUG_CPU
171 //ust// int (*handle_cpuhp) (struct notifier_block *nb,
172 //ust// unsigned long action, void *hcpu,
173 //ust// struct ltt_trace_struct *trace);
175 } ____cacheline_aligned
;
177 struct ltt_transport
{
179 struct module
*owner
;
180 struct list_head node
;
181 struct ltt_trace_ops ops
;
184 enum trace_mode
{ LTT_TRACE_NORMAL
, LTT_TRACE_FLIGHT
, LTT_TRACE_HYBRID
};
186 #define CHANNEL_FLAG_ENABLE (1U<<0)
187 #define CHANNEL_FLAG_OVERWRITE (1U<<1)
189 /* Per-trace information - each trace/flight recorder represented by one */
190 struct ltt_trace_struct
{
191 /* First 32 bytes cache-hot cacheline */
192 struct list_head list
;
193 struct ltt_trace_ops
*ops
;
195 /* Second 32 bytes cache-hot cacheline */
196 struct ltt_channel_struct
*channels
;
197 unsigned int nr_channels
;
201 unsigned long long start_monotonic
;
202 struct timeval start_time
;
203 struct ltt_channel_setting
*settings
;
205 struct dentry
*trace_root
;
207 //ust// struct rchan_callbacks callbacks;
208 struct kref kref
; /* Each channel has a kref of the trace struct */
209 struct ltt_transport
*transport
;
210 struct kref ltt_transport_kref
;
211 //ust// wait_queue_head_t kref_wq; /* Place for ltt_trace_destroy to sleep */
212 char trace_name
[NAME_MAX
];
213 } ____cacheline_aligned
;
215 /* Hardcoded event headers
217 * event header for a trace with active heartbeat : 27 bits timestamps
219 * headers are 32-bits aligned. In order to insure such alignment, a dynamic per
220 * trace alignment value must be done.
222 * Remember that the C compiler does align each member on the boundary
223 * equivalent to their own size.
225 * As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
226 * bytes aligned, so the buffer header and trace header are aligned.
228 * Event headers are aligned depending on the trace alignment option.
230 * Note using C structure bitfields for cross-endianness and portability
234 #define LTT_RESERVED_EVENTS 3
235 #define LTT_EVENT_BITS 5
236 #define LTT_FREE_EVENTS ((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
237 #define LTT_TSC_BITS 27
238 #define LTT_TSC_MASK ((1 << LTT_TSC_BITS) - 1)
240 struct ltt_event_header
{
241 u32 id_time
; /* 5 bits event id (MSB); 27 bits time (LSB) */
244 /* Reservation flags */
245 #define LTT_RFLAG_ID (1 << 0)
246 #define LTT_RFLAG_ID_SIZE (1 << 1)
247 #define LTT_RFLAG_ID_SIZE_TSC (1 << 2)
250 * We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
251 * specifically with CPU frequency scaling someday, so using an interpolation
252 * between the start and end of buffer values is not flexible enough. Using an
253 * immediate frequency value permits to calculate directly the times for parts
254 * of a buffer that would be before a frequency change.
256 * Keep the natural field alignment for _each field_ within this structure if
257 * you ever add/remove a field from this header. Packed attribute is not used
258 * because gcc generates poor code on at least powerpc and mips. Don't ever
259 * let gcc add padding between the structure elements.
261 struct ltt_subbuffer_header
{
262 uint64_t cycle_count_begin
; /* Cycle count at subbuffer start */
263 uint64_t cycle_count_end
; /* Cycle count at subbuffer end */
264 uint32_t magic_number
; /*
265 * Trace magic number.
266 * contains endianness information.
268 uint8_t major_version
;
269 uint8_t minor_version
;
270 uint8_t arch_size
; /* Architecture pointer size */
271 uint8_t alignment
; /* LTT data alignment */
272 uint64_t start_time_sec
; /* NTP-corrected start time */
273 uint64_t start_time_usec
;
274 uint64_t start_freq
; /*
275 * Frequency at trace start,
276 * used all along the trace.
278 uint32_t freq_scale
; /* Frequency scaling (divisor) */
279 uint32_t lost_size
; /* Size unused at end of subbuffer */
280 uint32_t buf_size
; /* Size of this subbuffer */
281 uint32_t events_lost
; /*
282 * Events lost in this subbuffer since
283 * the beginning of the trace.
286 uint32_t subbuf_corrupt
; /*
287 * Corrupted (lost) subbuffers since
288 * the begginig of the trace.
291 uint8_t header_end
[0]; /* End of header */
295 * ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
297 * Return header size without padding after the structure. Don't use packed
298 * structure because gcc generates inefficient code on some architectures
301 static inline size_t ltt_subbuffer_header_size(void)
303 return offsetof(struct ltt_subbuffer_header
, header_end
);
307 * ltt_get_header_size
309 * Calculate alignment offset to 32-bits. This is the alignment offset of the
313 * The event header must be 32-bits. The total offset calculated here :
315 * Alignment of header struct on 32 bits (min arch size, header size)
316 * + sizeof(header struct) (32-bits)
317 * + (opt) u16 (ext. event id)
318 * + (opt) u16 (event_size) (if event_size == 0xFFFFUL, has ext. event size)
319 * + (opt) u32 (ext. event size)
320 * + (opt) u64 full TSC (aligned on min(64-bits, arch size))
322 * The payload must itself determine its own alignment from the biggest type it
325 static inline unsigned char ltt_get_header_size(
326 struct ltt_channel_struct
*channel
,
329 size_t *before_hdr_pad
,
332 size_t orig_offset
= offset
;
335 BUILD_BUG_ON(sizeof(struct ltt_event_header
) != sizeof(u32
));
337 padding
= ltt_align(offset
, sizeof(struct ltt_event_header
));
339 offset
+= sizeof(struct ltt_event_header
);
342 case LTT_RFLAG_ID_SIZE_TSC
:
343 offset
+= sizeof(u16
) + sizeof(u16
);
344 if (data_size
>= 0xFFFFU
)
345 offset
+= sizeof(u32
);
346 offset
+= ltt_align(offset
, sizeof(u64
));
347 offset
+= sizeof(u64
);
349 case LTT_RFLAG_ID_SIZE
:
350 offset
+= sizeof(u16
) + sizeof(u16
);
351 if (data_size
>= 0xFFFFU
)
352 offset
+= sizeof(u32
);
355 offset
+= sizeof(u16
);
359 *before_hdr_pad
= padding
;
360 return offset
- orig_offset
;
364 * ltt_write_event_header
366 * Writes the event header to the offset (already aligned on 32-bits).
368 * @trace : trace to write to.
369 * @channel : pointer to the channel structure..
370 * @buf : buffer to write to.
371 * @buf_offset : buffer offset to write to (aligned on 32 bits).
373 * @event_size : size of the event, excluding the event header.
374 * @tsc : time stamp counter.
375 * @rflags : reservation flags.
377 * returns : offset where the event data must be written.
379 static inline size_t ltt_write_event_header(struct ltt_trace_struct
*trace
,
380 struct ltt_channel_struct
*channel
,
381 struct rchan_buf
*buf
, long buf_offset
,
382 u16 eID
, size_t event_size
,
383 u64 tsc
, unsigned int rflags
)
385 struct ltt_event_header header
;
389 case LTT_RFLAG_ID_SIZE_TSC
:
390 header
.id_time
= 29 << LTT_TSC_BITS
;
392 case LTT_RFLAG_ID_SIZE
:
393 header
.id_time
= 30 << LTT_TSC_BITS
;
396 header
.id_time
= 31 << LTT_TSC_BITS
;
399 header
.id_time
= eID
<< LTT_TSC_BITS
;
402 header
.id_time
|= (u32
)tsc
& LTT_TSC_MASK
;
403 ltt_relay_write(buf
, buf_offset
, &header
, sizeof(header
));
404 buf_offset
+= sizeof(header
);
407 case LTT_RFLAG_ID_SIZE_TSC
:
408 small_size
= min_t(size_t, event_size
, 0xFFFFU
);
409 ltt_relay_write(buf
, buf_offset
,
410 (u16
[]){ (u16
)eID
}, sizeof(u16
));
411 buf_offset
+= sizeof(u16
);
412 ltt_relay_write(buf
, buf_offset
,
413 (u16
[]){ (u16
)small_size
}, sizeof(u16
));
414 buf_offset
+= sizeof(u16
);
415 if (small_size
== 0xFFFFU
) {
416 ltt_relay_write(buf
, buf_offset
,
417 (u32
[]){ (u32
)event_size
}, sizeof(u32
));
418 buf_offset
+= sizeof(u32
);
420 buf_offset
+= ltt_align(buf_offset
, sizeof(u64
));
421 ltt_relay_write(buf
, buf_offset
,
422 (u64
[]){ (u64
)tsc
}, sizeof(u64
));
423 buf_offset
+= sizeof(u64
);
425 case LTT_RFLAG_ID_SIZE
:
426 small_size
= min_t(size_t, event_size
, 0xFFFFU
);
427 ltt_relay_write(buf
, buf_offset
,
428 (u16
[]){ (u16
)eID
}, sizeof(u16
));
429 buf_offset
+= sizeof(u16
);
430 ltt_relay_write(buf
, buf_offset
,
431 (u16
[]){ (u16
)small_size
}, sizeof(u16
));
432 buf_offset
+= sizeof(u16
);
433 if (small_size
== 0xFFFFU
) {
434 ltt_relay_write(buf
, buf_offset
,
435 (u32
[]){ (u32
)event_size
}, sizeof(u32
));
436 buf_offset
+= sizeof(u32
);
440 ltt_relay_write(buf
, buf_offset
,
441 (u16
[]){ (u16
)eID
}, sizeof(u16
));
442 buf_offset
+= sizeof(u16
);
453 /* Buffer offset macros */
456 * BUFFER_TRUNC zeroes the subbuffer offset and the subbuffer number parts of
457 * the offset, which leaves only the buffer number.
459 #define BUFFER_TRUNC(offset, chan) \
460 ((offset) & (~((chan)->alloc_size-1)))
461 #define BUFFER_OFFSET(offset, chan) ((offset) & ((chan)->alloc_size - 1))
462 #define SUBBUF_OFFSET(offset, chan) ((offset) & ((chan)->subbuf_size - 1))
463 #define SUBBUF_ALIGN(offset, chan) \
464 (((offset) + (chan)->subbuf_size) & (~((chan)->subbuf_size - 1)))
465 #define SUBBUF_TRUNC(offset, chan) \
466 ((offset) & (~((chan)->subbuf_size - 1)))
467 #define SUBBUF_INDEX(offset, chan) \
468 (BUFFER_OFFSET((offset), chan) >> (chan)->subbuf_size_order)
473 * Atomic slot reservation in a LTTng buffer. It will take care of
474 * sub-buffer switching.
478 * @trace : the trace structure to log to.
479 * @channel : the chanel to reserve space into.
480 * @transport_data : specific transport data.
481 * @data_size : size of the variable length data to log.
482 * @slot_size : pointer to total size of the slot (out)
483 * @buf_offset : pointer to reserve offset (out)
484 * @tsc : pointer to the tsc at the slot reservation (out)
485 * @rflags : reservation flags (header specificity)
488 * Return : -ENOSPC if not enough space, else 0.
490 static inline int ltt_reserve_slot(
491 struct ltt_trace_struct
*trace
,
492 struct ltt_channel_struct
*channel
,
493 void **transport_data
,
498 unsigned int *rflags
,
502 return trace
->ops
->reserve_slot(trace
, channel
, transport_data
,
503 data_size
, slot_size
, buf_offset
, tsc
, rflags
,
511 * Atomic unordered slot commit. Increments the commit count in the
512 * specified sub-buffer, and delivers it if necessary.
516 * @channel : the chanel to reserve space into.
517 * @transport_data : specific transport data.
518 * @buf_offset : offset of beginning of reserved slot
519 * @slot_size : size of the reserved slot.
521 static inline void ltt_commit_slot(
522 struct ltt_channel_struct
*channel
,
523 void **transport_data
,
527 struct ltt_trace_struct
*trace
= channel
->trace
;
529 trace
->ops
->commit_slot(channel
, transport_data
, buf_offset
, slot_size
);
541 //ust// #define LTT_RELAY_ROOT "ltt"
542 //ust// #define LTT_RELAY_LOCKED_ROOT "ltt-locked"
544 #define LTT_METADATA_CHANNEL "metadata_state"
545 #define LTT_UST_CHANNEL "ust"
547 #define LTT_FLIGHT_PREFIX "flight-"
549 /* Tracer properties */
550 #define LTT_DEFAULT_SUBBUF_SIZE_LOW 65536
551 #define LTT_DEFAULT_N_SUBBUFS_LOW 2
552 #define LTT_DEFAULT_SUBBUF_SIZE_MED 262144
553 #define LTT_DEFAULT_N_SUBBUFS_MED 2
554 #define LTT_DEFAULT_SUBBUF_SIZE_HIGH 1048576
555 #define LTT_DEFAULT_N_SUBBUFS_HIGH 2
556 #define LTT_TRACER_MAGIC_NUMBER 0x00D6B7ED
557 #define LTT_TRACER_VERSION_MAJOR 2
558 #define LTT_TRACER_VERSION_MINOR 3
561 * Size reserved for high priority events (interrupts, NMI, BH) at the end of a
562 * nearly full buffer. User space won't use this last amount of space when in
563 * blocking mode. This space also includes the event header that would be
564 * written by this user space event.
566 #define LTT_RESERVE_CRITICAL 4096
568 /* Register and unregister function pointers */
570 enum ltt_module_function
{
571 LTT_FUNCTION_RUN_FILTER
,
572 LTT_FUNCTION_FILTER_CONTROL
,
573 LTT_FUNCTION_STATEDUMP
576 //ust// extern int ltt_module_register(enum ltt_module_function name, void *function,
577 //ust// struct module *owner);
578 //ust// extern void ltt_module_unregister(enum ltt_module_function name);
580 void ltt_transport_register(struct ltt_transport
*transport
);
581 void ltt_transport_unregister(struct ltt_transport
*transport
);
583 /* Exported control function */
585 //ust// enum ltt_control_msg {
586 //ust// LTT_CONTROL_START,
587 //ust// LTT_CONTROL_STOP,
588 //ust// LTT_CONTROL_CREATE_TRACE,
589 //ust// LTT_CONTROL_DESTROY_TRACE
592 union ltt_control_args
{
594 enum trace_mode mode
;
595 unsigned int subbuf_size_low
;
596 unsigned int n_subbufs_low
;
597 unsigned int subbuf_size_med
;
598 unsigned int n_subbufs_med
;
599 unsigned int subbuf_size_high
;
600 unsigned int n_subbufs_high
;
604 int _ltt_trace_setup(const char *trace_name
);
605 int ltt_trace_setup(const char *trace_name
);
606 struct ltt_trace_struct
*_ltt_trace_find_setup(const char *trace_name
);
607 int ltt_trace_set_type(const char *trace_name
, const char *trace_type
);
608 int ltt_trace_set_channel_subbufsize(const char *trace_name
,
609 const char *channel_name
, unsigned int size
);
610 int ltt_trace_set_channel_subbufcount(const char *trace_name
,
611 const char *channel_name
, unsigned int cnt
);
612 int ltt_trace_set_channel_enable(const char *trace_name
,
613 const char *channel_name
, unsigned int enable
);
614 int ltt_trace_set_channel_overwrite(const char *trace_name
,
615 const char *channel_name
, unsigned int overwrite
);
616 int ltt_trace_alloc(const char *trace_name
);
617 int ltt_trace_destroy(const char *trace_name
);
618 int ltt_trace_start(const char *trace_name
);
619 int ltt_trace_stop(const char *trace_name
);
621 //ust// extern int ltt_control(enum ltt_control_msg msg, const char *trace_name,
622 //ust// const char *trace_type, union ltt_control_args args);
624 enum ltt_filter_control_msg
{
625 LTT_FILTER_DEFAULT_ACCEPT
,
626 LTT_FILTER_DEFAULT_REJECT
629 extern int ltt_filter_control(enum ltt_filter_control_msg msg
,
630 const char *trace_name
);
632 extern struct dentry
*get_filter_root(void);
634 void ltt_write_trace_header(struct ltt_trace_struct
*trace
,
635 struct ltt_subbuffer_header
*header
);
636 extern void ltt_buffer_destroy(struct ltt_channel_struct
*ltt_chan
);
638 void ltt_core_register(int (*function
)(u8
, void *));
640 void ltt_core_unregister(void);
642 void ltt_release_trace(struct kref
*kref
);
643 void ltt_release_transport(struct kref
*kref
);
645 extern int ltt_probe_register(struct ltt_available_probe
*pdata
);
646 extern int ltt_probe_unregister(struct ltt_available_probe
*pdata
);
647 extern int ltt_marker_connect(const char *channel
, const char *mname
,
649 extern int ltt_marker_disconnect(const char *channel
, const char *mname
,
651 extern void ltt_dump_marker_state(struct ltt_trace_struct
*trace
);
653 void ltt_lock_traces(void);
654 void ltt_unlock_traces(void);
656 //ust// extern void ltt_dump_softirq_vec(void *call_data);
658 //ust// #ifdef CONFIG_HAVE_LTT_DUMP_TABLES
659 //ust// extern void ltt_dump_sys_call_table(void *call_data);
660 //ust// extern void ltt_dump_idt_table(void *call_data);
662 //ust// static inline void ltt_dump_sys_call_table(void *call_data)
666 //ust// static inline void ltt_dump_idt_table(void *call_data)
671 //ust// #ifdef CONFIG_LTT_KPROBES
672 //ust// extern void ltt_dump_kprobes_table(void *call_data);
674 //ust// static inline void ltt_dump_kprobes_table(void *call_data)
679 //ust// /* Relay IOCTL */
681 //ust// /* Get the next sub buffer that can be read. */
682 //ust// #define RELAY_GET_SUBBUF _IOR(0xF5, 0x00, __u32)
683 //ust// /* Release the oldest reserved (by "get") sub buffer. */
684 //ust// #define RELAY_PUT_SUBBUF _IOW(0xF5, 0x01, __u32)
685 //ust// /* returns the number of sub buffers in the per cpu channel. */
686 //ust// #define RELAY_GET_N_SUBBUFS _IOR(0xF5, 0x02, __u32)
687 //ust// /* returns the size of the sub buffers. */
688 //ust// #define RELAY_GET_SUBBUF_SIZE _IOR(0xF5, 0x03, __u32)
690 //ust// #endif /* CONFIG_LTT */
692 #endif /* _LTT_TRACER_H */