source: lib/libtrace_parallel.h @ 76291d1

4.0.1-hotfixescachetimestampsdevelopdpdk-ndagetsilivelibtrace4ndag_formatpfringrc-4.0.1rc-4.0.2rc-4.0.3rc-4.0.4ringdecrementfixringperformanceringtimestampfixes
Last change on this file since 76291d1 was 76291d1, checked in by Richard Sanger <rsangerarj@…>, 6 years ago

Add a quick mockup of shanes interface using functions for each message

I.e. set a function for MESSAGE_PACKET etc. which only receives packets.

Ported tracestats_parallel to use this interface.

Note it is not yet complete, however should give a feel of how it will work.
And provide a good work around to the thread issues on older machines.

  • Property mode set to 100644
File size: 41.2 KB
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1/*
2 * This file is part of libtrace
3 *
4 * Copyright (c) 2007,2008,2009,2010 The University of Waikato, Hamilton,
5 * New Zealand.
6 *
7 * Authors: Richard Sanger
8 *
9 * All rights reserved.
10 *
11 * This code has been developed by the University of Waikato WAND
12 * research group. For further information please see http://www.wand.net.nz/
13 *
14 * libtrace is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * libtrace is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with libtrace; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
27 *
28 * $Id$
29 *
30 */
31
32/** @file
33 *
34 * @brief Header file containing definitions for structures and functions
35 * related to the parallel framework
36 *
37 * @author Richard Sanger
38 *
39 * @version $Id$
40 *
41 * The parallel libtrace framework is a replacement to the libtrace framework. XXX TODO MAKE MORE DOCS HERE.
42 */
43
44#ifndef LIBTRACE_PARALLEL_H
45#define LIBTRACE_PARALLEL_H
46
47#include "libtrace.h"
48#include <stdio.h>
49
50typedef struct libtrace_result_t libtrace_result_t;
51
52/**
53 * A collection of types for convenience used in place of a
54 * simple void* to allow a any type of data to be stored.
55 *
56 * This is expected to be 8 bytes in length.
57 */
58typedef union {
59        /* Pointers */
60        void *ptr;
61        libtrace_packet_t *pkt;
62        libtrace_result_t *res;
63
64        /* C99 Integer types */
65        /* NOTE: Standard doesn't require 64-bit
66         * but x32 and x64 gcc does */
67        int64_t sint64;
68        uint64_t uint64;
69
70        uint32_t uint32s[2];
71        int32_t sint32s[2];
72        uint32_t uint32;
73        int32_t sint32;
74
75        uint16_t uint16s[4];
76        int16_t sint16s[4];
77        uint16_t uint16;
78        int16_t sint16;
79
80        uint8_t uint8s[8];
81        int8_t sint8s[8];
82        uint8_t uint8;
83        int8_t sint8;
84
85        size_t size;
86
87        /* C basic types - we cannot be certain of the size */
88        int sint;
89        unsigned int uint;
90
91        signed char schars[8];
92        unsigned char uchars[8];
93        signed char schar;
94        unsigned char uchar;
95
96        /* Real numbers */
97        float rfloat;
98        double rdouble;
99} libtrace_generic_t;
100ct_assert(sizeof(libtrace_generic_t) == 8);
101
102typedef struct libtrace_message_t {
103        int code; /**< The message code see enum libtrace_messages */
104        libtrace_generic_t data; /**< Additional data related to the message */
105        libtrace_thread_t *sender; /**< The thread that sent the message */
106} libtrace_message_t;
107
108/** Structure holding information about a result */
109struct libtrace_result_t {
110        uint64_t key;
111        libtrace_generic_t value;
112        int type;
113};
114
115/** The libtrace_messages enum
116 * All libtrace messages are defined and documented here.
117 *
118 * Some messages can be sent to control the library while others
119 * are received by the per-packet and reporter functions to inform the libtrace
120 * application.
121 *
122 * If a user wishes to send there own custom messages they should use
123 * numbers greater than MESSAGE_USER (1000).
124 *
125 * @note Some messages are for internal use only
126 */
127enum libtrace_messages {
128        /** A libtrace packet is ready, this will only be sent to per
129         * packet threads.
130         * @param data Holds the packet in data.pkt. The packet belongs to
131         * libtrace and should either be returned from the per-packet function
132         * if no longer needed or free'd at some later time using the XXX
133         * function.
134         * @param sender The sender will be set as the current thread
135         */
136        MESSAGE_PACKET,
137        /** A libtrace result is ready, this will only be sent to the reporter
138         * thread.
139         * @param data Holds the result in data.res. The memory holding the
140         * result is allocated by libtrace and should not be free'd. However
141         * note that any data stored within the result might need to be free'd.
142         * @param sender The sender will be set as the current thread
143         */
144        MESSAGE_RESULT,
145
146        /** A message sent to each thread when it starts. This is sent
147         * to both the reporter and per-packet threads. This will be sent once
148         * after trace_pstart() (assuming no errors occurs).
149         *
150         * This can be used to allocate resources required by each thread.
151         *
152         * These can be free'd when MESSAGE_STOPPING is received.
153         *
154         * @param data unused, do not use this
155         * @param sender The sender will be set as the current thread
156         */
157        MESSAGE_STARTING,
158
159        /** A message sent to each thread when it stops. This is sent
160         * to both the reporter and per-packet threads. This will be sent once
161         * after MESSAGE_STARTING.
162         *
163         * This can be used to free any resources allocated with
164         * MESSAGE_STARTING.
165         *
166         * @param data unused, do not use this
167         * @param sender The sender will be set as the current thread
168         */
169        MESSAGE_STOPPING,
170
171        /** A message sent to each thread when a thread transitions between a
172         * paused (or unstarted) state to running state. This is sent
173         * to both the reporter and per-packet threads. This will be sent after
174         * MESSAGE_STARTING when a trace is first started and when a trace
175         * is started (trace_pstart()) after a pause (trace_ppause()).
176         *
177         * This can be used to allocate resources.
178         *
179         * @param data unused, do not use this
180         * @param sender The sender will be set as the current thread
181         */
182        MESSAGE_RESUMING,
183
184        /** A message sent to each thread when a thread transitions between a
185         * paused (or unstarted) state to running state. This is sent
186         * to both the reporter and per-packet threads. This will be sent after
187         * MESSAGE_STARTING when a trace is first started and when a trace
188         * is started (trace_pstart()) after a pause (trace_ppause()).
189         *
190         * This can be used to allocate resources.
191         *
192         * @param data unused, do not use this
193         * @param sender The sender will be set as the current thread
194         */
195        MESSAGE_PAUSING,
196
197        /** An internal message do not use this */
198        MESSAGE_DO_PAUSE,
199        /** An internal message do not use this */
200        MESSAGE_DO_STOP,
201
202        /** Sent to all per-packet threads (including the sender) and the
203         * reducer when the first packet is seen for a thread.
204         *
205         * @param data The first packet is stored in data.pkt. This packet is
206         * shared by all threads receiving the message and is valid until
207         * MESSAGE_PAUSING is received.
208         * @param sender The per-packet thread which received the packet
209         *
210         * @note Upon pausing and restarting a trace this will be reset and
211         * sent once a new packet is encountered
212         *
213         * @
214         */
215        MESSAGE_FIRST_PACKET,
216
217        /** Notify the reporter thread more data is available.
218         *
219         * Triggers the reporter to read as many results as possible.
220         *
221         * @param data unused
222         * @param sender the sending
223         *
224         * @note This message should not be sent directly instead call
225         * trace_post_reporter()
226         *
227         * @see trace_get_first_packet()
228         */
229        MESSAGE_POST_REPORTER,
230
231        /** Sent to per-packet threads periodically after the configured time
232         * interval has passed.
233         *
234         * This is sent out-of-band with respect to packets and as a result
235         * can appear after a packet with an later time-stamp, or before one
236         * with an earlier time-stamp.
237         *
238         * @param data data.uint64_t holds the system time-stamp in the
239         * erf format
240         * @param sender should be ignored
241         */
242        MESSAGE_TICK_INTERVAL,
243
244        /** Sent to per-packet threads once the configured number of packets
245         * are read from a trace.
246         *
247         * This are sent in-band with respect to packets such that all
248         * threads will see it between the same packets.
249         *
250         * @param data The number of packets seen so far across all threads
251         * @param sender Set to the current per-packet thread
252         */
253        MESSAGE_TICK_COUNT,
254
255        /** For specific user defined messages use codes of MESSAGE_USER or above. */
256        MESSAGE_USER = 1000
257};
258
259/** The hasher types available to libtrace application.
260 * These can be selected using trace_set_hasher().
261 */
262enum hasher_types {
263        /** Balance load across per-packet threads as best as possible, this is
264         * basically to say I do not care about where packets are sent. This
265         * might still might be implemented using a hash or round robin etc.
266         * depending on the format and libtrace configuration.
267         */
268        HASHER_BALANCE,
269
270        /** Use a hash which is bi-directional for TCP and UDP flows, that is
271         * packets with the same 5-tuple are sent to the same per-packet thread.
272         * All non TCP/UDP packets will be sent to the same thread.
273         *
274         * @note it is possible that UDP packets may not be spread across
275         * per-packet threads, depending upon the format support. In this case
276         * they would be directed to a single per-packet thread.
277         */
278        HASHER_BIDIRECTIONAL,
279
280        /** Use a hash which is uni-directional across TCP and UDP flows, this
281         * means the opposing directions of the same 5-tuple might end up on
282         * different per-packet threads.
283         * Otherwise this is identical to HASHER_BIDIRECTIONAL
284         */
285        HASHER_UNIDIRECTIONAL,
286
287        /**
288         * Always use the user supplied hasher, this disables native
289         * support in and is likely significantly slower.
290         */
291        HASHER_CUSTOM
292};
293
294typedef struct libtrace_info_t {
295        /**
296         * True if a live format (i.e. packets have to be trace-time).
297         * Otherwise false, indicating packets can be read as fast
298         * as possible from the format.
299         */
300        bool live;
301
302        /**
303         * The maximum number of threads supported by a parallel trace. 1
304         * if parallel support is not native (in this case libtrace will simulate
305         * an unlimited number of threads), -1 means unlimited and 0 unknown.
306         */
307        int max_threads;
308
309        /* TODO hash fn supported list */
310
311        /* TODO consider time/clock details?? */
312} libtrace_info_t;
313
314/**
315 * The methods we use to combine multiple outputs into a single output
316 * This is not considered a stable API however is public.
317 * Where possible use built in combiners.
318 *
319 * @note this structure is duplicated per trace and as such can
320 * have functions rewritten, and in fact should if possible.
321 */
322typedef struct libtrace_combine libtrace_combine_t;
323struct libtrace_combine {
324
325        /**
326         * Called at the start of the trace to allow data-structures
327         * to be initialised and allow functions to be swapped if appropriate.
328         *
329         * Also factors such as whether the trace is live or not can
330         * be used to determine the functions used.
331         * @return 0 if successful, -1 if an error occurs
332         */
333        int (*initialise)(libtrace_t *,libtrace_combine_t *);
334
335        /**
336         * Called when the trace ends, clean up any memory here
337         * from libtrace_t * init.
338         */
339        void (*destroy)(libtrace_t *, libtrace_combine_t *);
340
341        /**
342         * Publish a result against it's a threads queue.
343         * If null publish directly, expected to be used
344         * as a single threaded optimisation and can be
345         * set to NULL by init if this case is detected.
346         *
347         * TODO this is old info
348         */
349        void (*publish)(libtrace_t *, int thread_id, libtrace_combine_t *, libtrace_result_t *);
350
351        /**
352         * Read as many results as possible from the trace.
353         * Directly calls the users code to handle results from here.
354         *
355         * THIS SHOULD BE NON-BLOCKING AND READ AS MANY AS POSSIBLE
356         * If publish is NULL, this probably should be NULL also otherwise
357         * it will not be called.
358         */
359        void (*read)(libtrace_t *, libtrace_combine_t *);
360
361        /**
362         * Called when the trace is finished to flush the final
363         * results to the reporter thread.
364         *
365         * There may be no results, in which case this should
366         * just return.
367         *
368         * Libtrace state:
369         * Called from reporter thread
370         * No perpkt threads will be running, i.e. publish will not be
371         * called again.
372         *
373         * If publish is NULL, this probably should be NULL also otherwise
374         * it will not be called.
375         */
376        void (*read_final)(libtrace_t *, libtrace_combine_t *);
377
378        /**
379         * Pause must make sure any results of the type packet are safe.
380         * That means trace_copy_packet() and destroy the original.
381         * This also should be NULL if publish is NULL.
382         */
383        void (*pause)(libtrace_t *, libtrace_combine_t *);
384
385        /**
386         * Data storage for all the combiner threads
387         */
388        void *queues;
389
390        /**
391         * Configuration options, what this does is up to the combiner
392         * chosen.
393         */
394        libtrace_generic_t configuration;
395};
396
397/**
398 * The definition for the main function that the user supplies to process
399 * packets.
400 *
401 * @param trace The trace the packet is related to.
402 * @param thread The thread identifier.
403 * @param mesg_code The type of data ready, the most important being MESSAGE_PACKET.
404 * In this case data.pkt contains the packet.
405 * @param data A generic union of types that fit into 8 bytes, containing
406 * information dependent upon the mesg_code.
407 * @param sender The thread from which the message originated.
408 * @return If the message type is MESSAGE_PACKET a packet can be returned back
409 * to the library similar to trace_free_packet() otherwise this should be NULL.
410 *
411 * The values of data and sender depend upon the mesg_code. Please see the
412 * documentation for the message as to what value these will contain.
413 */
414typedef void* (*fn_per_pkt)(libtrace_t* trace,
415                            libtrace_thread_t *thread,
416                            int mesg_code,
417                            libtrace_generic_t data,
418                            libtrace_thread_t *sender);
419
420/**
421 * The definition for the main function that the user supplies to process
422 * results from trace_publish_result().
423 *
424 * @param trace The trace the packet is related to.
425 * @param mesg_code The type of data ready, the most important being MESSAGE_RESULT.
426 * In this case data.res contains the result.
427 * @param data A generic union of types that fit into 8 bytes, containing
428 * information dependent upon the mesg_code.
429 * @param sender The thread from which the message originated.
430 *
431 * The values of data and sender depend upon the mesg_code. Please see the
432 * documentation for the message as to what value these will contain.
433 */
434typedef void (*fn_reporter)(libtrace_t* trace,
435                            int mesg_code,
436                            libtrace_generic_t data,
437                            libtrace_thread_t *sender);
438
439/**
440 * The definition for a hasher function, allowing matching packets to be
441 * directed to the same per packet thread for processing.
442 *
443 * @param packet The packet to be hashed.
444 * @param data A void pointer which can contain additional information,
445 * such as configuration of the hasher function.
446 */
447typedef uint64_t (*fn_hasher)(const libtrace_packet_t* packet, void *data);
448
449
450/** Start or restart an input trace in the parallel libtrace framework.
451 *
452 * @param libtrace The input trace to start
453 * @param global_blob Global data related to this trace accessible using trace_get_global()
454 * @param per_pkt A user supplied function called when a packet is ready
455 * @param reporter A user supplied function called when a result is ready.
456 * Optional if NULL the reporter thread will not be started.
457 * @return 0 on success, otherwise -1 to indicate an error has occurred
458 *
459 * This can also be used to restart an existing parallel trace,
460 * that has previously been paused using trace_ppause().
461 * In this case global_blob,per_pkt and reporter will only be updated
462 * if they are non-null. Otherwise their previous values will be maintained.
463 *
464 */
465DLLEXPORT int trace_pstart(libtrace_t *libtrace, void* global_blob,
466                           fn_per_pkt per_pkt, fn_reporter reporter);
467
468
469/**
470 * @param libtrace The parallel trace
471 * @param t The thread
472 * @param data The data associated with the message
473 * @param global The global storage
474 * @param tls The thread local storage
475 */
476typedef void* (*fn_handler)(libtrace_t *libtrace,
477                               libtrace_thread_t *t,
478                               libtrace_generic_t data,
479                               void *global,
480                               void *tls);
481
482/** Registers a built-in message with a handler.
483 * Note we do not include the sending thread as an argument to the reporter.
484 * If set to NULL, the message will be sent to default perpkt handler.
485 *
486 * @param libtrace The input trace to start
487 * @param message The message to intercept
488 * @param handler the handler to be called when the message is received
489 * @return 0 if successful otherwise -1.
490 */
491DLLEXPORT int trace_set_handler(libtrace_t *libtrace, enum libtrace_messages message, fn_handler handler);
492
493/** Pauses a trace previously started with trace_pstart()
494 *
495 * @param libtrace The parallel trace to be paused
496 * @return 0 on success, otherwise -1 to indicate an error has occurred
497 *
498 */
499DLLEXPORT int trace_ppause(libtrace_t *libtrace);
500
501/** Stops a parallel trace, causing all threads to exit as if an EOF
502 * has occurred. This replaces trace_interrupt(), allowing
503 * a specified trace to be stopped.
504 *
505 * @param libtrace The parallel trace to be stopped
506 * @return 0 on success, otherwise -1 to indicate an error has occurred
507 *
508 * This should only be called by the main thread.
509 *
510 */
511DLLEXPORT int trace_pstop(libtrace_t *libtrace);
512
513/** Waits for a trace to finish and all threads to join.
514 *
515 * @param trace The parallel trace
516 *
517 * Waits for a trace to finish, whether this be due to
518 * an error occurring, an EOF or trace_pstop.
519 *
520 */
521DLLEXPORT void trace_join(libtrace_t * trace);
522
523/**
524 * @name User Data Storage
525 *
526 * These method provide a way for users to store data against a trace or
527 * a thread.
528 *
529 * Alternatively one could use global variables and thread local
530 * storage (__thread), respectively, which in many cases could be simpler.
531 *
532 * @note We do not lock on reads, instead we rely on the
533 * processor making any writes appear atomically.
534 *
535 * @{
536 */
537
538/** Returns the data stored against a trace.
539 *
540 * @param trace The parallel trace
541 * @return The stored data.
542 */
543DLLEXPORT void * trace_get_local(libtrace_t *trace);
544
545/** Store data against a trace so that all threads can access it
546 * using trace_get_global().
547 *
548 * @param trace The parallel trace.
549 * @param data The new value to save against the trace
550 * @return The previously stored value
551 *
552 * The update to the previous value is atomic and thread-safe.
553 *
554 * @note Although this is thread-safe another thread may still be
555 * using the previous data, as such further synchronisation is needed
556 * if a thread wanted to free the existing value.
557 */
558DLLEXPORT void * trace_set_local(libtrace_t *trace, void * data);
559
560/** Returns the users data stored against a thread.
561 *
562 * @param thread The thread
563 * @return The stored data
564 */
565DLLEXPORT void * trace_get_tls(libtrace_thread_t *thread);
566
567/** Store data against a thread.
568 *
569 * @param The parallel trace.
570 * @param data The new value to save against the trace
571 * @return The previously stored value
572 *
573 * This function is not thread-safe and is intended only to be
574 * called on the currently running thread.
575 */
576DLLEXPORT void * trace_set_tls(libtrace_thread_t *thread, void * data);
577
578/// @}
579
580
581/**
582 * @name Parallel Configuration
583 *
584 * These methods provide a way to configure the parallel libtrace library.
585 *
586 * Many of these options are typically unneeded by most applications as they
587 * control tuning aspects of the library and are more useful to the
588 * end user.
589 *
590 * To allow the end user to change this configuration libtrace will search for
591 * three environment variables and apply them to the configuration in the
592 * following order. Such that the first has the lowest priority.
593 *
594 * 1. LIBTRACE_CONF, The global environment configuration
595 * 2. LIBTRACE_CONF_<FORMAT>, Applied to a given format
596 * 3. LIBTRACE_CONF_<FORMAT_URI>, Applied the specified trace
597 *
598 * E.g.
599 * - int:eth0 would match LIBTRACE_CONF, LIBTRACE_CONF_INT, LIBTRACE_CONF_INT_ETH0
600 * - dag:/dev/dag0,0 would match LIBTRACE_CONF, LIBTRACE_CONF_DAG, LIBTRACE_CONF_DAG__DEV_DAG0_0
601 * - test.erf would match LIBTRACE_CONF, LIBTRACE_CONF_ERF, LIBTRACE_CONF_ERF_TEST_ERF
602 *
603 * @note All environment variables names MUST only contain
604 * [A-Z], [0-9] and [_] (underscore). Any characters
605 * outside of this range should be capitalised if possible or replaced with an
606 * underscore.
607 * @{
608 */
609
610/** Set the maximum number of perpkt threads to use in a trace.
611 *
612 * @param[in] trace The parallel input trace
613 * @param[in] nb The number of threads to use. If 0 use default.
614 * @return 0 if successful otherwise -1
615 */
616DLLEXPORT int trace_set_perpkt_threads(libtrace_t *trace, int nb);
617
618/** Set the interval between tick messages in milliseconds.
619 *
620 * @param[in] trace The parallel input trace
621 * @param[in] millisec The interval in milliseconds. If 0 this is disabled [default].
622 * @return 0 if successful otherwise -1
623 *
624 * When a underlying parallel live trace is used MESSAGE_TICK_INTERVAL is sent
625 * every tick interval to all per-packet threads to ensure data is received.
626 * This allows results to be printed even in cases flows are not being directed
627 * to a per-packet thread, while still maintaining order etc.
628 *
629 * @note Tick count is preferred over tick interval and will be used rather
630 * than tick interval if possible.
631 * @see MESSAGE_TICK_INTERVAL, trace_set_tick_count()
632 */
633DLLEXPORT int trace_set_tick_interval(libtrace_t *trace, size_t millisec);
634
635/** Set the count between tick messages.
636 *
637 * @param[in] trace The parallel input trace
638 * @param[in] count The tick count.  If 0 this is disabled [default].
639 * @return 0 if successful otherwise -1
640 *
641 * When an underlying trace is accessed internally by libtrace in a
642 * single-threaded manner MESSAGE_TICK_COUNT is sent to all per-packet threads
643 * after every count packets have been seen in the trace. This allows results
644 * to be printed even in cases flows are not being directed to a per-packet
645 * thread, while still maintaining order etc.
646 *
647 * @see MESSAGE_TICK_COUNT, trace_set_tick_interval()
648 */
649DLLEXPORT int trace_set_tick_count(libtrace_t *trace, size_t count);
650
651/**
652 * Delays packets so they are played back in trace-time rather than as fast
653 * as possible (real-time).
654 *
655 * @param A parallel input trace
656 * @param tracetime If true packets are released with time intervals matching
657 * the original trace. Otherwise packets are read as fast as possible.
658 * @return 0 if successful otherwise -1
659 */
660DLLEXPORT int trace_set_tracetime(libtrace_t *trace, bool tracetime);
661
662/** This sets the maximum size of the freelist used to store empty packets
663 * and their memory buffers.
664 *
665 * @param trace A parallel input trace
666 * @param size The number of empty packets to cache in memory. Set to the
667 * default, 0, to autoconfigure this value.
668 * @return 0 if successful otherwise -1
669 *
670 * Internally libtrace maintains a buffer of packet structures, this buffer
671 * includes a cache per thread and a shared main pool. This configures
672 * the size of the main pool. If an application is not passing packets
673 * through to the reducer step --- that is to say returns packets from
674 * the perpkt function --- this buffer will not need to be used.
675 *
676 * @note Setting this too low could cause performance issues or a deadlock. An
677 * unblockable warning will be printed.
678 *
679 * @see trace_set_thread_cache_size(), trace_set_fixed_count()
680 */
681DLLEXPORT int trace_set_cache_size(libtrace_t *trace, size_t size);
682
683/** This sets the maximum size of the freelist thread cache's used to provide
684 * faster access than the main shared pool.
685 *
686 * @param trace A parallel input trace
687 * @param size The number of empty packets to cache in memory. Set to the
688 * default, 0, to autoconfigure this value.
689 * @return 0 if successful otherwise -1
690 *
691 * @see trace_set_cache_size(), trace_set_fixed_count()
692 */
693DLLEXPORT int trace_set_thread_cache_size(libtrace_t *trace, size_t size);
694
695/** If true the total number of packets that can be created by a trace is limited
696 * to that set by trace_set_cache_size(), otherwise once exceeded malloc
697 * and free will be used to create and free packets, this will be slower than
698 * using the freelist and could run a machine out of memory.
699 *
700 * @param trace A parallel input trace
701 * @param fixed If true the total number of packets is limited, otherwise
702 * it is not. Defaults to false.
703 * @return 0 if successful otherwise -1
704 *
705 * @see trace_set_thread_cache_size(), trace_set_cache_size()
706 */
707DLLEXPORT int trace_set_fixed_count(libtrace_t *trace, bool fixed);
708
709/** The number of packets to batch together for processing internally
710 * by libtrace.
711 *
712 * @param trace A parallel input trace
713 * @param size The total number of packets to batch together. Set to the
714 * default, 0, to autoconfigure this value.
715 * @return 0 if successful otherwise -1
716 *
717 * Internally libtrace will attempt to read up to this number of packets from
718 * a format typically values of 10 will get good performance and increasing
719 * beyond that will should little difference.
720 *
721 * @note We still pass a single packet at a time to the perpkt function
722 */
723DLLEXPORT int trace_set_burst_size(libtrace_t *trace, size_t size);
724
725/**
726 * See diagrams, this sets the maximum size of buffers used between
727 * the single hasher thread and the buffer.
728 * NOTE setting this to less than recommend could cause deadlock a
729 * trace that manages its own packets.
730 * A unblockable warning message will be printed to stderr in this case.
731 */
732/** The number of packets that can queue per thread from hasher thread */
733DLLEXPORT int trace_set_hasher_queue_size(libtrace_t *trace, size_t size);
734
735/** If true use a polling hasher queue, that means that we will spin/or yield
736 * when data is not available rather than blocking on a condition.
737 *
738 * @param trace A parallel input trace
739 * @param polling If true the hasher will poll waiting for data, otherwise
740 * it is not. Defaults to false.
741 *
742 * We note this is likely to waste many CPU cycles and could even decrease
743 * performance.
744 *
745 * @return 0 if successful otherwise -1
746 */
747DLLEXPORT int trace_set_hasher_polling(libtrace_t *trace, bool polling);
748
749/** If true the reporter thread will continuously poll waiting for results
750 * if false they are only checked when a message is received, this message
751 * is controlled by reporter_thold.
752 *
753 * @param trace A parallel input trace
754 * @param polling If true the reporter will poll waiting for data, otherwise
755 * it is not. Defaults to false.
756 * @return 0 if successful otherwise -1
757 *
758 * We note this is likely to waste many CPU cycles and could even decrease
759 * performance.
760 *
761 * @note This setting could be ignored by some reporters.
762 */
763DLLEXPORT int trace_set_reporter_polling(libtrace_t *trace, bool polling);
764
765/** Set the perpkt thread result queue size before triggering the reporter
766 * to read results.
767 *
768 * @param trace A parallel input trace
769 * @param thold The threshold on the number of results to enqueue before
770 * notifying the reporter thread to read them.
771 * @return 0 if successful otherwise -1
772 *
773 *
774 * @note This setting is generally ignored if trace_set_reporter_polling() is
775 * set however some combiner functions might ignore trace_set_reporter_polling()
776 * and still require this to be set.
777 * @see trace_publish_result(), trace_post_reporter()
778 */
779DLLEXPORT int trace_set_reporter_thold(libtrace_t *trace, size_t thold);
780
781/** Prints a line to standard error for every state change
782 * for both the trace as a whole and for each thread.
783 *
784 * @param trace A parallel input trace
785 * @param debug_state If true debug is printed. Defaults false.
786 * @return 0 if successful otherwise -1.
787 *
788 */
789DLLEXPORT int trace_set_debug_state(libtrace_t *trace, bool debug_state);
790
791/** Set the hasher function for a parallel trace.
792 *
793 * @param[in] trace The parallel trace to apply the hasher to
794 * @param[in] type The type of hashing to apply, see enum hasher_types
795 * @param[in] hasher A hasher function to use [Optional]
796 * @param[in] data Data passed to the hasher function [Optional]
797 *
798 * @return 0 if successful otherwise -1 on error
799 *
800 * The hasher function in a parallel trace can be used to control which
801 * per-packet thread a packets is processed by.
802 *
803 * HASHER_BALANCE is the default and will dispatch packets as fast as possible
804 * to all threads arbitrarily. As such when called the hasher and
805 * data parameters must be set to NULL.
806 *
807 * HASHER_CUSTOM will force the libtrace to use the user defined function. As
808 * such the hasher parameter must be supplied.
809 *
810 * With other defined hasher types we will try to push the hashing into the format
811 * by default. In this case the hasher parameter is optional and will be
812 * preferred over the default supplied by libtrace.
813 *
814 * @note When supplying a hasher function it should be thread-safe so it can
815 * be run in parallel by libtrace. Ideally this should rely upon no state, other
816 * than some form of seed value supplied in data.
817 */
818DLLEXPORT int trace_set_hasher(libtrace_t *trace, enum hasher_types type,
819                               fn_hasher hasher, void *data);
820
821/// @}
822
823
824/** Types of results.
825 * Some result types require special handling by combiners
826 * as such making use of built-in types is important.
827 *
828 * Custom result types users should be defined as RESULT_USER(1000) or greater.
829 *
830 */
831enum result_types {
832        /**
833         * The result is a packet in some circumstances special handling needs
834         * to be performed. As such packets should always be published as so.
835         *
836         * @param key (Typically) The packets order, see trace_packet_get_order()
837         * @param
838         */
839        RESULT_PACKET,
840
841        /** The result is a tick message
842         *
843         * @param key The erf time-stamp of the tick
844         */
845        RESULT_TICK_INTERVAL,
846
847        /** The result is a tick message
848         *
849         * @param key The sequence number of the tick message
850         */
851        RESULT_TICK_COUNT,
852
853        /** Any user specific codes should be above this.
854         *
855         */
856        RESULT_USER = 1000
857
858};
859
860/** Publish a result for to the combiner destined for the reporter thread
861 *
862 * @param[in] libtrace The parallel input trace
863 * @param[in] t The current per-packet thread
864 * @param[in] key The key of the result (used for sorting by the combiner)
865 * @param[in] value The value of the result
866 * @param[in] type The type of result see the documentation for the result_types enum
867 */
868DLLEXPORT void trace_publish_result(libtrace_t *libtrace,
869                                    libtrace_thread_t *t,
870                                    uint64_t key,
871                                    libtrace_generic_t value,
872                                    int type);
873
874/** Check if a dedicated hasher thread is being used.
875 *
876 * @param[in] libtrace The parallel input trace
877 * @return True if the trace has dedicated hasher thread otherwise false.
878 *
879 * This is valid once the trace is running after calling trace_pstart().
880 */
881DLLEXPORT bool trace_has_dedicated_hasher(libtrace_t * libtrace);
882
883/** Checks if a trace is using a reporter
884 *
885 * @param[in] libtrace The parallel input trace
886 * @return True if the trace is using a reporter otherwise false
887 */
888DLLEXPORT bool trace_has_reporter(libtrace_t * libtrace);
889
890/** Post a message to the reporter thread requesting it to check for more
891 * results.
892 *
893 * @param[in] The parallel input trace
894 * @return -1 upon error indicating the message has not been sent otherwise a
895 * backlog indicator (the number of messages the reporter has not yet read).
896 */
897DLLEXPORT int trace_post_reporter(libtrace_t *libtrace);
898
899/** Check the number of messages waiting in a queue
900 *
901 * @param[in] libtrace The input trace
902 * @param[in] t The thread to check, if NULL the current thread will be used [Optional]
903 *
904 * @return packets in the queue otherwise -1 upon error.
905 *
906 * @note For best performance it is recommended to supply the thread argument
907 * even if it is the current thread.
908 */
909DLLEXPORT int libtrace_thread_get_message_count(libtrace_t * libtrace,
910                                                libtrace_thread_t *t);
911
912/** Read a message from a thread in a blocking fashion
913 *
914 * @param[in] libtrace The input trace
915 * @param[in] t The thread to check, if NULL the current thread will be used [Optional]
916 * @param[out] message A pointer to libtrace_message_t structure which will be
917 * filled with the retrieved message.
918 *
919 * @return The number of messages remaining otherwise -1 upon error.
920 *
921 *
922 * @note For best performance it is recommended to supply the thread argument
923 * even if it is the current thread.
924 */
925DLLEXPORT int libtrace_thread_get_message(libtrace_t * libtrace,
926                                          libtrace_thread_t *t,
927                                          libtrace_message_t * message);
928
929/** Read a message from a thread in a blocking fashion
930 *
931 * @param[in] libtrace The input trace
932 * @param[in] t The thread to check, if NULL the current thread will be used [Optional]
933 * @param[out] message A pointer to libtrace_message_t structure which will be
934 * filled with the retrieved message.
935 *
936 * @return 0 if successful otherwise -1 upon error or if no packets were available.
937 *
938 *
939 * @note For best performance it is recommended to supply the thread argument
940 * even if it is the current thread.
941 */
942DLLEXPORT int libtrace_thread_try_get_message(libtrace_t * libtrace,
943                                              libtrace_thread_t *t,
944                                              libtrace_message_t * message);
945
946/** Send a message to the reporter thread
947 *
948 * @param[in] libtrace The parallel trace
949 * @param[in] message The message to be sent, if sender is NULL libtrace will
950 * attempt to fill this in. It is faster to assign this if it is known.
951 *
952 * @return -1 upon error indicating the message has not been sent otherwise a
953 * backlog indicator (the number of messages the reporter has not yet read).
954 */
955DLLEXPORT int trace_message_reporter(libtrace_t * libtrace,
956                                     libtrace_message_t * message);
957
958/** Send a message to all per-packet threads
959 *
960 * @param[in] libtrace The parallel trace
961 * @param[in] message The message to be sent, if sender is NULL libtrace will
962 * attempt to fill this in. It is faster to assign this if it is known.
963 *
964 * @return 0 if successful otherwise a negative number indicating the number
965 * of per-packet threads the message was not sent to (i.e. -1 means one thread
966 * could not be sent the message).
967 */
968DLLEXPORT int trace_message_perpkts(libtrace_t * libtrace,
969                                    libtrace_message_t * message);
970
971/** Send a message to a thread
972 *
973 * @param[in] libtrace The parallel trace
974 * @param[in] t The thread to message
975 * @param[in] message The message to be sent, if sender is NULL libtrace will
976 * attempt to fill this in. It is faster to assign this if it is known.
977 *
978 * @return -1 upon error indicating the message has not been sent otherwise a
979 * backlog indicator (the number of messages the thread has not yet read).
980 */
981DLLEXPORT int trace_message_thread(libtrace_t * libtrace,
982                                   libtrace_thread_t *t,
983                                   libtrace_message_t * message);
984
985/** Check if a parallel trace has finished reading packets
986 *
987 * @return True if the trace has finished reading packets (even if all results
988 * have not yet been processed). Otherwise false.
989 *
990 * @note This returns true even if all results have not yet been processed.
991 */
992DLLEXPORT bool trace_has_finished(libtrace_t * libtrace);
993
994/** Returns either the sequence number or erf timestamp of a packet.
995 *
996 * @param[in] packet
997 * @return A 64bit sequence number or erf timestamp.
998 *
999 * The returned value can be used to compare if packets come before or after
1000 * others.
1001 */
1002DLLEXPORT uint64_t trace_packet_get_order(libtrace_packet_t * packet);
1003
1004/** Returns the hash of a packet.
1005 *
1006 * @param[in] packet
1007 * @return A 64-bit hash
1008 *
1009 * @note In many cases this might not be filled in, only in cases where
1010 * a custom hash is being used. You can use trace_has_dedicated_hasher()
1011 * to check if this will be valid.
1012 */
1013DLLEXPORT uint64_t trace_packet_get_hash(libtrace_packet_t * packet);
1014
1015/** Sets the order of a packet.
1016 *
1017 * @param[in] packet
1018 * @param[in] order the new order of a packet
1019 *
1020 * @note many combiners rely on this value, ensure changing this conforms to
1021 * the combiners requirements.
1022 */
1023DLLEXPORT void trace_packet_set_order(libtrace_packet_t * packet, uint64_t order);
1024
1025/** Sets the hash of a packet.
1026 *
1027 * @param[in] packet
1028 * @param[in] hash the new hash
1029 *
1030 * Once handed to the user the libtrace library has little use for this field
1031 * and as such this can essentially be used for any storage the user requires.
1032 */
1033DLLEXPORT void trace_packet_set_hash(libtrace_packet_t * packet, uint64_t hash);
1034
1035/** TODO WHAT TO DO WITH THIS ? */
1036DLLEXPORT uint64_t tv_to_usec(const struct timeval *tv);
1037
1038
1039/** Returns the first packet of a parallel trace since it was started or
1040 * restarted.
1041 *
1042 * @param[in] libtrace the parallel input trace
1043 * @param[in] t Either a per packet thread or NULL to retrieve the first packet
1044 * of across all per packet threads.
1045 * @param[out] packet A pointer to the first packet in the trace. [Optional]
1046 * @param[out] tv The system time-stamp when this packet was received. [Optional]
1047 * @return 1 if we are confident this is the first packet. Otherwise 0 if this
1048 * is a best guess (this is only possible int the case t=NULL)
1049 * in which case we recommend calling this at a later time.
1050 * -1 is returned if an error occurs, such as supplied a invalid thread.
1051 *
1052 * The packet and timeval returned by this function is shared by all threads
1053 * and remain valid until MESSAGE_PAUSING is received.
1054 */
1055DLLEXPORT int trace_get_first_packet(libtrace_t *libtrace,
1056                                     libtrace_thread_t *t,
1057                                     const libtrace_packet_t **packet,
1058                                     const struct timeval **tv);
1059
1060/** Makes a packet safe, a packet will become invalid after a
1061 * pausing a trace.
1062 *
1063 * @param[in,out] pkt The packet to make safe
1064 *
1065 * This copies a packet in such a way that it will be able to survive a pause.
1066 * However this will not allow the packet to be used after
1067 * the format is destroyed.
1068 */
1069DLLEXPORT void libtrace_make_packet_safe(libtrace_packet_t *pkt);
1070
1071/** Makes a result safe if a result contains a packet.
1072 *
1073 * @param[in,out] res The result to make safe.
1074 *
1075 * This ensures the internal content of a result is safe to survive a pause.
1076 * See libtrace_make_packet_safe().
1077 */
1078DLLEXPORT void libtrace_make_result_safe(libtrace_result_t *res);
1079
1080/** In a parallel trace, free a packet back to libtrace.
1081 *
1082 * @param[in] libtrace A parallel input trace
1083 * @param[in] packet The packet to be released back to libtrace
1084 *
1085 * The packet should not be used after calling this function.
1086 *
1087 * @note All packets should be free'd before a trace is destroyed.
1088 */
1089DLLEXPORT void trace_free_packet(libtrace_t * libtrace, libtrace_packet_t * packet);
1090
1091
1092DLLEXPORT libtrace_info_t *trace_get_information(libtrace_t * libtrace);
1093
1094/** Sets the configuration of a trace based upon a comma separated list of
1095 * key value pairs.
1096 *
1097 * @param trace A parallel trace which is not running or destroyed
1098 * @param str A comma separated list of key=value pairs.
1099 * E.g. \em "burst_size=20,perpkt_threads=2,fixed_count=true"
1100 * @return 0 if successful otherwise -1. If bad options are passed we will
1101 * print the error to stderr but still return successful.
1102 *
1103 * List of keys:
1104 * * \b cache_size,\b cs see trace_set_cache_size() [size_t]
1105 * * \b thread_cache_size,\b tcs see trace_set_thread_cache_size() [size_t]
1106 * * \b fixed_count,\b fc see trace_set_fixed_count() [bool]
1107 * * \b burst_size,\b bs see trace_set_burst_size() [size_t]
1108 * * \b tick_interval,\b ti see trace_set_tick_interval() [size_t]
1109 * * \b tick_count,\b tc see trace_set_tick_count() [size_t]
1110 * * \b perpkt_threads,\b pt see trace_set_perpkt_threads() [XXX TBA XXX]
1111 * * \b hasher_queue_size,\b hqs see trace_set_hasher_queue_size() [size_t]
1112 * * \b hasher_polling,\b hp see trace_set_hasher_polling() [bool]
1113 * * \b reporter_polling,\b rp see trace_set_reporter_polling() [bool]
1114 * * \b reporter_thold,\b rt see trace_set_reporter_thold() [size_t]
1115 * * \b debug_state,\b ds see trace_set_debug_state() [bool]
1116 *
1117 * Booleans can be set as 0/1 or false/true.
1118 *
1119 * @note a environment variable interface is provided by default to users via
1120 * LIBTRACE_CONF, see Parallel Configuration for more information.
1121 *
1122 * @note this interface is provided to allow a user to configure an application
1123 * if a libtrace applicate wishes to configure a setting it should use a
1124 * trace_set_*() function with the same name.
1125 */
1126DLLEXPORT int trace_set_configuration(libtrace_t *trace, const char * str);
1127
1128/** Sets configuration from a file. This reads every line from the file and
1129 * interprets each line with trace_set_configuration().
1130 *
1131 * @param trace A parallel trace which is not running or destroyed
1132 * @param file A file pointer which we read each line from
1133 * @return 0 if successful otherwise -1. If bad options are passed we will
1134 * print the error to stderr but still return successful.
1135 *
1136 * @note We do not close the file pointer upon completion
1137 */
1138DLLEXPORT int trace_set_configuration_file(libtrace_t *trace, FILE *file);
1139
1140DLLEXPORT int libtrace_get_perpkt_count(libtrace_t* t); // TODO MATCH WITH THE SET_PERPKT
1141
1142/**
1143 * Sets a combiner function against the trace.
1144 *
1145 * @param trace The input trace
1146 * @combiner The combiner to use
1147 * @config config Configuration information. Dependent upon the combiner in use
1148 *
1149 * Sets a combiner against a trace, this should only be called on a
1150 * non-started or paused trace.  By default combiner_unordered
1151 * will be used.
1152 */
1153DLLEXPORT void trace_set_combiner(libtrace_t *trace, const libtrace_combine_t *combiner, libtrace_generic_t config);
1154
1155/**
1156 * Takes unordered (or ordered) input and produces unordered output.
1157 * Basically you get the result quickly but in no particular order.
1158 */
1159extern const libtrace_combine_t combiner_unordered;
1160
1161/**
1162 * Takes ordered input and produces ordered output. Perpkt threads
1163 * the output results must be ordered for this to work correctly!!
1164 */
1165extern const libtrace_combine_t combiner_ordered;
1166
1167/**
1168 * Like classic Google Map/Reduce, the results are sorted
1169 * in ascending order, this is only done when the trace finishes.
1170 *
1171 * This only works with a limited number of results, otherwise
1172 * we will just run out of memory and crash!! You should always
1173 * use combiner_ordered if you can.
1174 */
1175extern const libtrace_combine_t combiner_sorted;
1176
1177#endif // LIBTRACE_PARALLEL_H
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