ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/IO-AIO/AIO.xs
Revision: 1.34
Committed: Tue Aug 23 00:03:14 2005 UTC (18 years, 8 months ago) by root
Branch: MAIN
Changes since 1.33: +2 -0 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #define _REENTRANT 1
2 #include <errno.h>
3
4 #include "EXTERN.h"
5 #include "perl.h"
6 #include "XSUB.h"
7
8 #include "autoconf/config.h"
9
10 #include <pthread.h>
11
12 #include <sys/types.h>
13 #include <sys/stat.h>
14
15 #include <unistd.h>
16 #include <fcntl.h>
17 #include <signal.h>
18 #include <sched.h>
19
20 #if HAVE_SENDFILE
21 # if __linux
22 # include <sys/sendfile.h>
23 # elif __freebsd
24 # include <sys/socket.h>
25 # include <sys/uio.h>
26 # elif __hpux
27 # include <sys/socket.h>
28 # else
29 # error sendfile support requested but not available
30 # endif
31 #endif
32
33 #if __ia64
34 # define STACKSIZE 65536
35 #else
36 # define STACKSIZE 4096
37 #endif
38
39 enum {
40 REQ_QUIT,
41 REQ_OPEN, REQ_CLOSE,
42 REQ_READ, REQ_WRITE, REQ_READAHEAD,
43 REQ_SENDFILE,
44 REQ_STAT, REQ_LSTAT, REQ_FSTAT,
45 REQ_FSYNC, REQ_FDATASYNC,
46 REQ_UNLINK, REQ_RMDIR,
47 REQ_SYMLINK,
48 };
49
50 typedef struct aio_cb {
51 struct aio_cb *volatile next;
52
53 int type;
54
55 int fd, fd2;
56 off_t offset;
57 size_t length;
58 ssize_t result;
59 mode_t mode; /* open */
60 int errorno;
61 SV *data, *callback;
62 SV *fh, *fh2;
63 void *dataptr, *data2ptr;
64 STRLEN dataoffset;
65
66 Stat_t *statdata;
67 } aio_cb;
68
69 typedef aio_cb *aio_req;
70
71 static int started, wanted;
72 static volatile int nreqs;
73 static int max_outstanding = 1<<30;
74 static int respipe [2];
75
76 static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
77 static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
78 static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
79
80 static volatile aio_req reqs, reqe; /* queue start, queue end */
81 static volatile aio_req ress, rese; /* queue start, queue end */
82
83 static void free_req (aio_req req)
84 {
85 if (req->data)
86 SvREFCNT_dec (req->data);
87
88 if (req->fh)
89 SvREFCNT_dec (req->fh);
90
91 if (req->fh2)
92 SvREFCNT_dec (req->fh2);
93
94 if (req->statdata)
95 Safefree (req->statdata);
96
97 if (req->callback)
98 SvREFCNT_dec (req->callback);
99
100 Safefree (req);
101 }
102
103 static void
104 poll_wait ()
105 {
106 if (nreqs && !ress)
107 {
108 fd_set rfd;
109 FD_ZERO(&rfd);
110 FD_SET(respipe [0], &rfd);
111
112 select (respipe [0] + 1, &rfd, 0, 0, 0);
113 }
114 }
115
116 static int
117 poll_cb ()
118 {
119 dSP;
120 int count = 0;
121 int do_croak = 0;
122 aio_req req;
123
124 for (;;)
125 {
126 pthread_mutex_lock (&reslock);
127 req = ress;
128
129 if (req)
130 {
131 ress = req->next;
132
133 if (!ress)
134 {
135 /* read any signals sent by the worker threads */
136 char buf [32];
137 while (read (respipe [0], buf, 32) == 32)
138 ;
139
140 rese = 0;
141 }
142 }
143
144 pthread_mutex_unlock (&reslock);
145
146 if (!req)
147 break;
148
149 nreqs--;
150
151 if (req->type == REQ_QUIT)
152 started--;
153 else
154 {
155 int errorno = errno;
156 errno = req->errorno;
157
158 if (req->type == REQ_READ)
159 SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));
160
161 if (req->data2ptr && (req->type == REQ_READ || req->type == REQ_WRITE))
162 SvREADONLY_off (req->data);
163
164 if (req->statdata)
165 {
166 PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
167 PL_laststatval = req->result;
168 PL_statcache = *(req->statdata);
169 }
170
171 ENTER;
172 PUSHMARK (SP);
173 XPUSHs (sv_2mortal (newSViv (req->result)));
174
175 if (req->type == REQ_OPEN)
176 {
177 /* convert fd to fh */
178 SV *fh;
179
180 PUTBACK;
181 call_pv ("IO::AIO::_fd2fh", G_SCALAR | G_EVAL);
182 SPAGAIN;
183
184 fh = SvREFCNT_inc (POPs);
185
186 PUSHMARK (SP);
187 XPUSHs (sv_2mortal (fh));
188 }
189
190 if (SvOK (req->callback))
191 {
192 PUTBACK;
193 call_sv (req->callback, G_VOID | G_EVAL);
194 SPAGAIN;
195
196 if (SvTRUE (ERRSV))
197 {
198 free_req (req);
199 croak (0);
200 }
201 }
202
203 LEAVE;
204
205 errno = errorno;
206 count++;
207 }
208
209 free_req (req);
210 }
211
212 return count;
213 }
214
215 static void *aio_proc(void *arg);
216
217 static void
218 start_thread (void)
219 {
220 sigset_t fullsigset, oldsigset;
221 pthread_t tid;
222 pthread_attr_t attr;
223
224 pthread_attr_init (&attr);
225 pthread_attr_setstacksize (&attr, STACKSIZE);
226 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
227
228 sigfillset (&fullsigset);
229 sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
230
231 if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
232 started++;
233
234 sigprocmask (SIG_SETMASK, &oldsigset, 0);
235 }
236
237 static void
238 send_req (aio_req req)
239 {
240 while (started < wanted && nreqs >= started)
241 start_thread ();
242
243 nreqs++;
244
245 pthread_mutex_lock (&reqlock);
246
247 req->next = 0;
248
249 if (reqe)
250 {
251 reqe->next = req;
252 reqe = req;
253 }
254 else
255 reqe = reqs = req;
256
257 pthread_cond_signal (&reqwait);
258 pthread_mutex_unlock (&reqlock);
259
260 if (nreqs > max_outstanding)
261 for (;;)
262 {
263 poll_cb ();
264
265 if (nreqs <= max_outstanding)
266 break;
267
268 poll_wait ();
269 }
270 }
271
272 static void
273 end_thread (void)
274 {
275 aio_req req;
276 Newz (0, req, 1, aio_cb);
277 req->type = REQ_QUIT;
278
279 send_req (req);
280 }
281
282 static void min_parallel (int nthreads)
283 {
284 if (wanted < nthreads)
285 wanted = nthreads;
286 }
287
288 static void max_parallel (int nthreads)
289 {
290 int cur = started;
291
292 if (wanted > nthreads)
293 wanted = nthreads;
294
295 while (cur > wanted)
296 {
297 end_thread ();
298 cur--;
299 }
300
301 while (started > wanted)
302 {
303 poll_wait ();
304 poll_cb ();
305 }
306 }
307
308 static void create_pipe ()
309 {
310 if (pipe (respipe))
311 croak ("unable to initialize result pipe");
312
313 if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
314 croak ("cannot set result pipe to nonblocking mode");
315
316 if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
317 croak ("cannot set result pipe to nonblocking mode");
318 }
319
320 static void atfork_prepare (void)
321 {
322 pthread_mutex_lock (&reqlock);
323 pthread_mutex_lock (&reslock);
324 }
325
326 static void atfork_parent (void)
327 {
328 pthread_mutex_unlock (&reslock);
329 pthread_mutex_unlock (&reqlock);
330 }
331
332 static void atfork_child (void)
333 {
334 aio_req prv;
335
336 started = 0;
337
338 while (reqs)
339 {
340 prv = reqs;
341 reqs = prv->next;
342 free_req (prv);
343 }
344
345 reqs = reqe = 0;
346
347 while (ress)
348 {
349 prv = ress;
350 ress = prv->next;
351 free_req (prv);
352 }
353
354 ress = rese = 0;
355
356 close (respipe [0]);
357 close (respipe [1]);
358 create_pipe ();
359
360 atfork_parent ();
361 }
362
363 /*****************************************************************************/
364 /* work around various missing functions */
365
366 #if !HAVE_PREADWRITE
367 # define pread aio_pread
368 # define pwrite aio_pwrite
369
370 /*
371 * make our pread/pwrite safe against themselves, but not against
372 * normal read/write by using a mutex. slows down execution a lot,
373 * but that's your problem, not mine.
374 */
375 static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;
376
377 static ssize_t
378 pread (int fd, void *buf, size_t count, off_t offset)
379 {
380 ssize_t res;
381 off_t ooffset;
382
383 pthread_mutex_lock (&iolock);
384 ooffset = lseek (fd, 0, SEEK_CUR);
385 lseek (fd, offset, SEEK_SET);
386 res = read (fd, buf, count);
387 lseek (fd, ooffset, SEEK_SET);
388 pthread_mutex_unlock (&iolock);
389
390 return res;
391 }
392
393 static ssize_t
394 pwrite (int fd, void *buf, size_t count, off_t offset)
395 {
396 ssize_t res;
397 off_t ooffset;
398
399 pthread_mutex_lock (&iolock);
400 ooffset = lseek (fd, 0, SEEK_CUR);
401 lseek (fd, offset, SEEK_SET);
402 res = write (fd, buf, count);
403 lseek (fd, offset, SEEK_SET);
404 pthread_mutex_unlock (&iolock);
405
406 return res;
407 }
408 #endif
409
410 #if !HAVE_FDATASYNC
411 # define fdatasync fsync
412 #endif
413
414 #if !HAVE_READAHEAD
415 # define readahead aio_readahead
416
417 static char readahead_buf[4096];
418
419 static ssize_t
420 readahead (int fd, off_t offset, size_t count)
421 {
422 while (count > 0)
423 {
424 size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
425
426 pread (fd, readahead_buf, len, offset);
427 offset += len;
428 count -= len;
429 }
430
431 errno = 0;
432 }
433 #endif
434
435 /* sendfile always needs emulation */
436 static ssize_t
437 sendfile_ (int ofd, int ifd, off_t offset, size_t count)
438 {
439 ssize_t res;
440
441 if (!count)
442 return 0;
443
444 #if __linux
445 res = sendfile (ofd, ifd, &offset, count);
446
447 #elif __freebsd
448 /*
449 * Of course, the freebsd sendfile is a dire hack with no thoughts
450 * wasted on making it similar to other i/o functions.
451 */
452 {
453 off_t sbytes;
454 res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);
455
456 if (!res && errno == EAGAIN)
457 /* maybe on others, too, as usual, the manpage leaves you guessing */
458 res = sbytes;
459 }
460
461 #elif __hpux
462 res = sendfile (ofd, ifd, offset, count, 0, 0);
463
464 #else
465 res = -1;
466 errno = ENOSYS;
467 #endif
468
469 if (res < 0 && (errno == ENOSYS || errno == EINVAL || errno == ENOTSOCK))
470 {
471 /* emulate sendfile. this is a major pain in the ass */
472 char *buf = malloc (4096);
473 res = 0;
474
475 for (;;)
476 {
477 ssize_t cnt;
478
479 cnt = pread (ifd, buf, 4096, offset);
480
481 if (cnt <= 0)
482 {
483 if (cnt && !res) res = -1;
484 break;
485 }
486
487 cnt = write (ofd, buf, cnt);
488
489 if (cnt <= 0)
490 {
491 if (cnt && !res) res = -1;
492 break;
493 }
494
495 offset += cnt;
496 res += cnt;
497 }
498
499 {
500 int errorno = errno;
501 free (buf);
502 errno = errorno;
503 }
504 }
505
506 return res;
507 }
508
509 /*****************************************************************************/
510
511 static void *
512 aio_proc (void *thr_arg)
513 {
514 aio_req req;
515 int type;
516
517 do
518 {
519 pthread_mutex_lock (&reqlock);
520
521 for (;;)
522 {
523 req = reqs;
524
525 if (reqs)
526 {
527 reqs = reqs->next;
528 if (!reqs) reqe = 0;
529 }
530
531 if (req)
532 break;
533
534 pthread_cond_wait (&reqwait, &reqlock);
535 }
536
537 pthread_mutex_unlock (&reqlock);
538
539 errno = 0; /* strictly unnecessary */
540
541 type = req->type;
542
543 switch (type)
544 {
545 case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
546 case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
547
548 case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
549 case REQ_SENDFILE: req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;
550
551 case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
552 case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
553 case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
554
555 case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
556 case REQ_CLOSE: req->result = close (req->fd); break;
557 case REQ_UNLINK: req->result = unlink (req->dataptr); break;
558 case REQ_RMDIR: req->result = rmdir (req->dataptr); break;
559 case REQ_SYMLINK: req->result = symlink (req->data2ptr, req->dataptr); break;
560
561 case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
562 case REQ_FSYNC: req->result = fsync (req->fd); break;
563
564 case REQ_QUIT:
565 break;
566
567 default:
568 req->result = ENOSYS;
569 break;
570 }
571
572 req->errorno = errno;
573
574 pthread_mutex_lock (&reslock);
575
576 req->next = 0;
577
578 if (rese)
579 {
580 rese->next = req;
581 rese = req;
582 }
583 else
584 {
585 rese = ress = req;
586
587 /* write a dummy byte to the pipe so fh becomes ready */
588 write (respipe [1], &respipe, 1);
589 }
590
591 pthread_mutex_unlock (&reslock);
592 }
593 while (type != REQ_QUIT);
594
595 return 0;
596 }
597
598 #define dREQ \
599 aio_req req; \
600 \
601 if (SvOK (callback) && !SvROK (callback)) \
602 croak ("clalback must be undef or of reference type"); \
603 \
604 Newz (0, req, 1, aio_cb); \
605 if (!req) \
606 croak ("out of memory during aio_req allocation"); \
607 \
608 req->callback = newSVsv (callback);
609
610 MODULE = IO::AIO PACKAGE = IO::AIO
611
612 PROTOTYPES: ENABLE
613
614 BOOT:
615 {
616 create_pipe ();
617 pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
618 }
619
620 void
621 min_parallel(nthreads)
622 int nthreads
623 PROTOTYPE: $
624
625 void
626 max_parallel(nthreads)
627 int nthreads
628 PROTOTYPE: $
629
630 int
631 max_outstanding(nreqs)
632 int nreqs
633 PROTOTYPE: $
634 CODE:
635 RETVAL = max_outstanding;
636 max_outstanding = nreqs;
637
638 void
639 aio_open(pathname,flags,mode,callback=&PL_sv_undef)
640 SV * pathname
641 int flags
642 int mode
643 SV * callback
644 PROTOTYPE: $$$;$
645 CODE:
646 {
647 dREQ;
648
649 req->type = REQ_OPEN;
650 req->data = newSVsv (pathname);
651 req->dataptr = SvPVbyte_nolen (req->data);
652 req->fd = flags;
653 req->mode = mode;
654
655 send_req (req);
656 }
657
658 void
659 aio_close(fh,callback=&PL_sv_undef)
660 SV * fh
661 SV * callback
662 PROTOTYPE: $;$
663 ALIAS:
664 aio_close = REQ_CLOSE
665 aio_fsync = REQ_FSYNC
666 aio_fdatasync = REQ_FDATASYNC
667 CODE:
668 {
669 dREQ;
670
671 req->type = ix;
672 req->fh = newSVsv (fh);
673 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
674
675 send_req (req);
676 }
677
678 void
679 aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
680 SV * fh
681 UV offset
682 UV length
683 SV * data
684 UV dataoffset
685 SV * callback
686 ALIAS:
687 aio_read = REQ_READ
688 aio_write = REQ_WRITE
689 PROTOTYPE: $$$$$;$
690 CODE:
691 {
692 aio_req req;
693 STRLEN svlen;
694 char *svptr = SvPVbyte (data, svlen);
695
696 SvUPGRADE (data, SVt_PV);
697 SvPOK_on (data);
698
699 if (dataoffset < 0)
700 dataoffset += svlen;
701
702 if (dataoffset < 0 || dataoffset > svlen)
703 croak ("data offset outside of string");
704
705 if (ix == REQ_WRITE)
706 {
707 /* write: check length and adjust. */
708 if (length < 0 || length + dataoffset > svlen)
709 length = svlen - dataoffset;
710 }
711 else
712 {
713 /* read: grow scalar as necessary */
714 svptr = SvGROW (data, length + dataoffset);
715 }
716
717 if (length < 0)
718 croak ("length must not be negative");
719
720 {
721 dREQ;
722
723 req->type = ix;
724 req->fh = newSVsv (fh);
725 req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
726 : IoOFP (sv_2io (fh)));
727 req->offset = offset;
728 req->length = length;
729 req->data = SvREFCNT_inc (data);
730 req->dataptr = (char *)svptr + dataoffset;
731
732 if (!SvREADONLY (data))
733 {
734 SvREADONLY_on (data);
735 req->data2ptr = (void *)data;
736 }
737
738 send_req (req);
739 }
740 }
741
742 void
743 aio_sendfile(out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
744 SV * out_fh
745 SV * in_fh
746 UV in_offset
747 UV length
748 SV * callback
749 PROTOTYPE: $$$$;$
750 CODE:
751 {
752 dREQ;
753
754 req->type = REQ_SENDFILE;
755 req->fh = newSVsv (out_fh);
756 req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
757 req->fh2 = newSVsv (in_fh);
758 req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
759 req->offset = in_offset;
760 req->length = length;
761
762 send_req (req);
763 }
764
765 void
766 aio_readahead(fh,offset,length,callback=&PL_sv_undef)
767 SV * fh
768 UV offset
769 IV length
770 SV * callback
771 PROTOTYPE: $$$;$
772 CODE:
773 {
774 dREQ;
775
776 req->type = REQ_READAHEAD;
777 req->fh = newSVsv (fh);
778 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
779 req->offset = offset;
780 req->length = length;
781
782 send_req (req);
783 }
784
785 void
786 aio_stat(fh_or_path,callback=&PL_sv_undef)
787 SV * fh_or_path
788 SV * callback
789 ALIAS:
790 aio_stat = REQ_STAT
791 aio_lstat = REQ_LSTAT
792 CODE:
793 {
794 dREQ;
795
796 New (0, req->statdata, 1, Stat_t);
797 if (!req->statdata)
798 {
799 free_req (req);
800 croak ("out of memory during aio_req->statdata allocation");
801 }
802
803 if (SvPOK (fh_or_path))
804 {
805 req->type = ix;
806 req->data = newSVsv (fh_or_path);
807 req->dataptr = SvPVbyte_nolen (req->data);
808 }
809 else
810 {
811 req->type = REQ_FSTAT;
812 req->fh = newSVsv (fh_or_path);
813 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
814 }
815
816 send_req (req);
817 }
818
819 void
820 aio_unlink(pathname,callback=&PL_sv_undef)
821 SV * pathname
822 SV * callback
823 ALIAS:
824 aio_unlink = REQ_UNLINK
825 aio_rmdir = REQ_RMDIR
826 CODE:
827 {
828 dREQ;
829
830 req->type = ix;
831 req->data = newSVsv (pathname);
832 req->dataptr = SvPVbyte_nolen (req->data);
833
834 send_req (req);
835 }
836
837 void
838 aio_symlink(oldpath,newpath,callback=&PL_sv_undef)
839 SV * oldpath
840 SV * newpath
841 SV * callback
842 CODE:
843 {
844 dREQ;
845
846 req->type = REQ_SYMLINK;
847 req->fh = newSVsv (oldpath);
848 req->data2ptr = SvPVbyte_nolen (req->fh);
849 req->data = newSVsv (newpath);
850 req->dataptr = SvPVbyte_nolen (req->data);
851
852 send_req (req);
853 }
854
855 void
856 flush()
857 PROTOTYPE:
858 CODE:
859 while (nreqs)
860 {
861 poll_wait ();
862 poll_cb ();
863 }
864
865 void
866 poll()
867 PROTOTYPE:
868 CODE:
869 if (nreqs)
870 {
871 poll_wait ();
872 poll_cb ();
873 }
874
875 int
876 poll_fileno()
877 PROTOTYPE:
878 CODE:
879 RETVAL = respipe [0];
880 OUTPUT:
881 RETVAL
882
883 int
884 poll_cb(...)
885 PROTOTYPE:
886 CODE:
887 RETVAL = poll_cb ();
888 OUTPUT:
889 RETVAL
890
891 void
892 poll_wait()
893 PROTOTYPE:
894 CODE:
895 if (nreqs)
896 poll_wait ();
897
898 int
899 nreqs()
900 PROTOTYPE:
901 CODE:
902 RETVAL = nreqs;
903 OUTPUT:
904 RETVAL
905