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/cvs/IO-AIO/AIO.xs
Revision: 1.36
Committed: Tue Aug 23 01:18:04 2005 UTC (18 years, 8 months ago) by root
Branch: MAIN
Changes since 1.35: +2 -14 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 # elif __solaris /* not yet */
29 # include <sys/sendfile.h>
30 # else
31 # error sendfile support requested but not available
32 # endif
33 #endif
34
35 #if __ia64
36 # define STACKSIZE 65536
37 #else
38 # define STACKSIZE 4096
39 #endif
40
41 enum {
42 REQ_QUIT,
43 REQ_OPEN, REQ_CLOSE,
44 REQ_READ, REQ_WRITE, REQ_READAHEAD,
45 REQ_SENDFILE,
46 REQ_STAT, REQ_LSTAT, REQ_FSTAT,
47 REQ_FSYNC, REQ_FDATASYNC,
48 REQ_UNLINK, REQ_RMDIR,
49 REQ_SYMLINK,
50 };
51
52 typedef struct aio_cb {
53 struct aio_cb *volatile next;
54
55 int type;
56
57 int fd, fd2;
58 off_t offset;
59 size_t length;
60 ssize_t result;
61 mode_t mode; /* open */
62 int errorno;
63 SV *data, *callback;
64 SV *fh, *fh2;
65 void *dataptr, *data2ptr;
66 STRLEN dataoffset;
67
68 Stat_t *statdata;
69 } aio_cb;
70
71 typedef aio_cb *aio_req;
72
73 static int started, wanted;
74 static volatile int nreqs;
75 static int max_outstanding = 1<<30;
76 static int respipe [2];
77
78 static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
79 static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
80 static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
81
82 static volatile aio_req reqs, reqe; /* queue start, queue end */
83 static volatile aio_req ress, rese; /* queue start, queue end */
84
85 static void free_req (aio_req req)
86 {
87 if (req->data)
88 SvREFCNT_dec (req->data);
89
90 if (req->fh)
91 SvREFCNT_dec (req->fh);
92
93 if (req->fh2)
94 SvREFCNT_dec (req->fh2);
95
96 if (req->statdata)
97 Safefree (req->statdata);
98
99 if (req->callback)
100 SvREFCNT_dec (req->callback);
101
102 Safefree (req);
103 }
104
105 static void
106 poll_wait ()
107 {
108 if (nreqs && !ress)
109 {
110 fd_set rfd;
111 FD_ZERO(&rfd);
112 FD_SET(respipe [0], &rfd);
113
114 select (respipe [0] + 1, &rfd, 0, 0, 0);
115 }
116 }
117
118 static int
119 poll_cb ()
120 {
121 dSP;
122 int count = 0;
123 int do_croak = 0;
124 aio_req req;
125
126 for (;;)
127 {
128 pthread_mutex_lock (&reslock);
129 req = ress;
130
131 if (req)
132 {
133 ress = req->next;
134
135 if (!ress)
136 {
137 /* read any signals sent by the worker threads */
138 char buf [32];
139 while (read (respipe [0], buf, 32) == 32)
140 ;
141
142 rese = 0;
143 }
144 }
145
146 pthread_mutex_unlock (&reslock);
147
148 if (!req)
149 break;
150
151 nreqs--;
152
153 if (req->type == REQ_QUIT)
154 started--;
155 else
156 {
157 int errorno = errno;
158 errno = req->errorno;
159
160 if (req->type == REQ_READ)
161 SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));
162
163 if (req->data2ptr && (req->type == REQ_READ || req->type == REQ_WRITE))
164 SvREADONLY_off (req->data);
165
166 if (req->statdata)
167 {
168 PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
169 PL_laststatval = req->result;
170 PL_statcache = *(req->statdata);
171 }
172
173 ENTER;
174 PUSHMARK (SP);
175 XPUSHs (sv_2mortal (newSViv (req->result)));
176
177 if (req->type == REQ_OPEN)
178 {
179 /* convert fd to fh */
180 SV *fh;
181
182 PUTBACK;
183 call_pv ("IO::AIO::_fd2fh", G_SCALAR | G_EVAL);
184 SPAGAIN;
185
186 fh = SvREFCNT_inc (POPs);
187
188 PUSHMARK (SP);
189 XPUSHs (sv_2mortal (fh));
190 }
191
192 if (SvOK (req->callback))
193 {
194 PUTBACK;
195 call_sv (req->callback, G_VOID | G_EVAL);
196 SPAGAIN;
197
198 if (SvTRUE (ERRSV))
199 {
200 free_req (req);
201 croak (0);
202 }
203 }
204
205 LEAVE;
206
207 errno = errorno;
208 count++;
209 }
210
211 free_req (req);
212 }
213
214 return count;
215 }
216
217 static void *aio_proc(void *arg);
218
219 static void
220 start_thread (void)
221 {
222 sigset_t fullsigset, oldsigset;
223 pthread_t tid;
224 pthread_attr_t attr;
225
226 pthread_attr_init (&attr);
227 pthread_attr_setstacksize (&attr, STACKSIZE);
228 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
229
230 sigfillset (&fullsigset);
231 sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
232
233 if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
234 started++;
235
236 sigprocmask (SIG_SETMASK, &oldsigset, 0);
237 }
238
239 static void
240 send_req (aio_req req)
241 {
242 while (started < wanted && nreqs >= started)
243 start_thread ();
244
245 nreqs++;
246
247 pthread_mutex_lock (&reqlock);
248
249 req->next = 0;
250
251 if (reqe)
252 {
253 reqe->next = req;
254 reqe = req;
255 }
256 else
257 reqe = reqs = req;
258
259 pthread_cond_signal (&reqwait);
260 pthread_mutex_unlock (&reqlock);
261
262 if (nreqs > max_outstanding)
263 for (;;)
264 {
265 poll_cb ();
266
267 if (nreqs <= max_outstanding)
268 break;
269
270 poll_wait ();
271 }
272 }
273
274 static void
275 end_thread (void)
276 {
277 aio_req req;
278 Newz (0, req, 1, aio_cb);
279 req->type = REQ_QUIT;
280
281 send_req (req);
282 }
283
284 static void min_parallel (int nthreads)
285 {
286 if (wanted < nthreads)
287 wanted = nthreads;
288 }
289
290 static void max_parallel (int nthreads)
291 {
292 int cur = started;
293
294 if (wanted > nthreads)
295 wanted = nthreads;
296
297 while (cur > wanted)
298 {
299 end_thread ();
300 cur--;
301 }
302
303 while (started > wanted)
304 {
305 poll_wait ();
306 poll_cb ();
307 }
308 }
309
310 static void create_pipe ()
311 {
312 if (pipe (respipe))
313 croak ("unable to initialize result pipe");
314
315 if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
316 croak ("cannot set result pipe to nonblocking mode");
317
318 if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
319 croak ("cannot set result pipe to nonblocking mode");
320 }
321
322 static void atfork_prepare (void)
323 {
324 pthread_mutex_lock (&reqlock);
325 pthread_mutex_lock (&reslock);
326 }
327
328 static void atfork_parent (void)
329 {
330 pthread_mutex_unlock (&reslock);
331 pthread_mutex_unlock (&reqlock);
332 }
333
334 static void atfork_child (void)
335 {
336 aio_req prv;
337
338 started = 0;
339
340 while (reqs)
341 {
342 prv = reqs;
343 reqs = prv->next;
344 free_req (prv);
345 }
346
347 reqs = reqe = 0;
348
349 while (ress)
350 {
351 prv = ress;
352 ress = prv->next;
353 free_req (prv);
354 }
355
356 ress = rese = 0;
357
358 close (respipe [0]);
359 close (respipe [1]);
360 create_pipe ();
361
362 atfork_parent ();
363 }
364
365 /*****************************************************************************/
366 /* work around various missing functions */
367
368 #if !HAVE_PREADWRITE
369 # define pread aio_pread
370 # define pwrite aio_pwrite
371
372 /*
373 * make our pread/pwrite safe against themselves, but not against
374 * normal read/write by using a mutex. slows down execution a lot,
375 * but that's your problem, not mine.
376 */
377 static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;
378
379 static ssize_t
380 pread (int fd, void *buf, size_t count, off_t offset)
381 {
382 ssize_t res;
383 off_t ooffset;
384
385 pthread_mutex_lock (&iolock);
386 ooffset = lseek (fd, 0, SEEK_CUR);
387 lseek (fd, offset, SEEK_SET);
388 res = read (fd, buf, count);
389 lseek (fd, ooffset, SEEK_SET);
390 pthread_mutex_unlock (&iolock);
391
392 return res;
393 }
394
395 static ssize_t
396 pwrite (int fd, void *buf, size_t count, off_t offset)
397 {
398 ssize_t res;
399 off_t ooffset;
400
401 pthread_mutex_lock (&iolock);
402 ooffset = lseek (fd, 0, SEEK_CUR);
403 lseek (fd, offset, SEEK_SET);
404 res = write (fd, buf, count);
405 lseek (fd, offset, SEEK_SET);
406 pthread_mutex_unlock (&iolock);
407
408 return res;
409 }
410 #endif
411
412 #if !HAVE_FDATASYNC
413 # define fdatasync fsync
414 #endif
415
416 #if !HAVE_READAHEAD
417 # define readahead aio_readahead
418
419 static char readahead_buf[4096];
420
421 static ssize_t
422 readahead (int fd, off_t offset, size_t count)
423 {
424 while (count > 0)
425 {
426 size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
427
428 pread (fd, readahead_buf, len, offset);
429 offset += len;
430 count -= len;
431 }
432
433 errno = 0;
434 }
435 #endif
436
437 /* sendfile always needs emulation */
438 static ssize_t
439 sendfile_ (int ofd, int ifd, off_t offset, size_t count)
440 {
441 ssize_t res;
442
443 if (!count)
444 return 0;
445
446 #if HAVE_SENDFILE
447 # if __linux
448 res = sendfile (ofd, ifd, &offset, count);
449
450 # elif __freebsd
451 /*
452 * Of course, the freebsd sendfile is a dire hack with no thoughts
453 * wasted on making it similar to other I/O functions.
454 */
455 {
456 off_t sbytes;
457 res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);
458
459 if (res < 0 && sbytes)
460 /* maybe only on EAGAIN only: as usual, the manpage leaves you guessing */
461 res = sbytes;
462 }
463
464 # elif __hpux
465 res = sendfile (ofd, ifd, offset, count, 0, 0);
466
467 # elif __solaris
468 {
469 struct sendfilevec vec;
470 size_t sbytes;
471
472 vec.sfv_fd = ifd;
473 vec.sfv_flag = 0;
474 vec.sfv_off = offset;
475 vec.sfv_len = count;
476
477 res = sendfilev (ofd, &vec, 1, &sbytes);
478
479 if (res < 0 && sbytes)
480 res = sbytes;
481 }
482
483 # else
484 res = -1;
485 errno = ENOSYS;
486 # endif
487 #endif
488
489 if (res < 0
490 && (errno == ENOSYS || errno == EINVAL || errno == ENOTSOCK
491 #if __solaris
492 || errno == EAFNOSUPPORT || errno == EPROTOTYPE
493 #endif
494 )
495 )
496 {
497 /* emulate sendfile. this is a major pain in the ass */
498 char *buf = malloc (4096);
499 res = 0;
500
501 for (;;)
502 {
503 ssize_t cnt;
504
505 cnt = pread (ifd, buf, 4096, offset);
506
507 if (cnt <= 0)
508 {
509 if (cnt && !res) res = -1;
510 break;
511 }
512
513 cnt = write (ofd, buf, cnt);
514
515 if (cnt <= 0)
516 {
517 if (cnt && !res) res = -1;
518 break;
519 }
520
521 offset += cnt;
522 res += cnt;
523 }
524
525 {
526 int errorno = errno;
527 free (buf);
528 errno = errorno;
529 }
530 }
531
532 return res;
533 }
534
535 /*****************************************************************************/
536
537 static void *
538 aio_proc (void *thr_arg)
539 {
540 aio_req req;
541 int type;
542
543 do
544 {
545 pthread_mutex_lock (&reqlock);
546
547 for (;;)
548 {
549 req = reqs;
550
551 if (reqs)
552 {
553 reqs = reqs->next;
554 if (!reqs) reqe = 0;
555 }
556
557 if (req)
558 break;
559
560 pthread_cond_wait (&reqwait, &reqlock);
561 }
562
563 pthread_mutex_unlock (&reqlock);
564
565 errno = 0; /* strictly unnecessary */
566
567 type = req->type;
568
569 switch (type)
570 {
571 case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
572 case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
573
574 case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
575 case REQ_SENDFILE: req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;
576
577 case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
578 case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
579 case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
580
581 case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
582 case REQ_CLOSE: req->result = close (req->fd); break;
583 case REQ_UNLINK: req->result = unlink (req->dataptr); break;
584 case REQ_RMDIR: req->result = rmdir (req->dataptr); break;
585 case REQ_SYMLINK: req->result = symlink (req->data2ptr, req->dataptr); break;
586
587 case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
588 case REQ_FSYNC: req->result = fsync (req->fd); break;
589
590 case REQ_QUIT:
591 break;
592
593 default:
594 req->result = ENOSYS;
595 break;
596 }
597
598 req->errorno = errno;
599
600 pthread_mutex_lock (&reslock);
601
602 req->next = 0;
603
604 if (rese)
605 {
606 rese->next = req;
607 rese = req;
608 }
609 else
610 {
611 rese = ress = req;
612
613 /* write a dummy byte to the pipe so fh becomes ready */
614 write (respipe [1], &respipe, 1);
615 }
616
617 pthread_mutex_unlock (&reslock);
618 }
619 while (type != REQ_QUIT);
620
621 return 0;
622 }
623
624 #define dREQ \
625 aio_req req; \
626 \
627 if (SvOK (callback) && !SvROK (callback)) \
628 croak ("clalback must be undef or of reference type"); \
629 \
630 Newz (0, req, 1, aio_cb); \
631 if (!req) \
632 croak ("out of memory during aio_req allocation"); \
633 \
634 req->callback = newSVsv (callback);
635
636 MODULE = IO::AIO PACKAGE = IO::AIO
637
638 PROTOTYPES: ENABLE
639
640 BOOT:
641 {
642 create_pipe ();
643 pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
644 }
645
646 void
647 min_parallel(nthreads)
648 int nthreads
649 PROTOTYPE: $
650
651 void
652 max_parallel(nthreads)
653 int nthreads
654 PROTOTYPE: $
655
656 int
657 max_outstanding(nreqs)
658 int nreqs
659 PROTOTYPE: $
660 CODE:
661 RETVAL = max_outstanding;
662 max_outstanding = nreqs;
663
664 void
665 aio_open(pathname,flags,mode,callback=&PL_sv_undef)
666 SV * pathname
667 int flags
668 int mode
669 SV * callback
670 PROTOTYPE: $$$;$
671 CODE:
672 {
673 dREQ;
674
675 req->type = REQ_OPEN;
676 req->data = newSVsv (pathname);
677 req->dataptr = SvPVbyte_nolen (req->data);
678 req->fd = flags;
679 req->mode = mode;
680
681 send_req (req);
682 }
683
684 void
685 aio_close(fh,callback=&PL_sv_undef)
686 SV * fh
687 SV * callback
688 PROTOTYPE: $;$
689 ALIAS:
690 aio_close = REQ_CLOSE
691 aio_fsync = REQ_FSYNC
692 aio_fdatasync = REQ_FDATASYNC
693 CODE:
694 {
695 dREQ;
696
697 req->type = ix;
698 req->fh = newSVsv (fh);
699 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
700
701 send_req (req);
702 }
703
704 void
705 aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
706 SV * fh
707 UV offset
708 UV length
709 SV * data
710 UV dataoffset
711 SV * callback
712 ALIAS:
713 aio_read = REQ_READ
714 aio_write = REQ_WRITE
715 PROTOTYPE: $$$$$;$
716 CODE:
717 {
718 aio_req req;
719 STRLEN svlen;
720 char *svptr = SvPVbyte (data, svlen);
721
722 SvUPGRADE (data, SVt_PV);
723 SvPOK_on (data);
724
725 if (dataoffset < 0)
726 dataoffset += svlen;
727
728 if (dataoffset < 0 || dataoffset > svlen)
729 croak ("data offset outside of string");
730
731 if (ix == REQ_WRITE)
732 {
733 /* write: check length and adjust. */
734 if (length < 0 || length + dataoffset > svlen)
735 length = svlen - dataoffset;
736 }
737 else
738 {
739 /* read: grow scalar as necessary */
740 svptr = SvGROW (data, length + dataoffset);
741 }
742
743 if (length < 0)
744 croak ("length must not be negative");
745
746 {
747 dREQ;
748
749 req->type = ix;
750 req->fh = newSVsv (fh);
751 req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
752 : IoOFP (sv_2io (fh)));
753 req->offset = offset;
754 req->length = length;
755 req->data = SvREFCNT_inc (data);
756 req->dataptr = (char *)svptr + dataoffset;
757
758 if (!SvREADONLY (data))
759 {
760 SvREADONLY_on (data);
761 req->data2ptr = (void *)data;
762 }
763
764 send_req (req);
765 }
766 }
767
768 void
769 aio_sendfile(out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
770 SV * out_fh
771 SV * in_fh
772 UV in_offset
773 UV length
774 SV * callback
775 PROTOTYPE: $$$$;$
776 CODE:
777 {
778 dREQ;
779
780 req->type = REQ_SENDFILE;
781 req->fh = newSVsv (out_fh);
782 req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
783 req->fh2 = newSVsv (in_fh);
784 req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
785 req->offset = in_offset;
786 req->length = length;
787
788 send_req (req);
789 }
790
791 void
792 aio_readahead(fh,offset,length,callback=&PL_sv_undef)
793 SV * fh
794 UV offset
795 IV length
796 SV * callback
797 PROTOTYPE: $$$;$
798 CODE:
799 {
800 dREQ;
801
802 req->type = REQ_READAHEAD;
803 req->fh = newSVsv (fh);
804 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
805 req->offset = offset;
806 req->length = length;
807
808 send_req (req);
809 }
810
811 void
812 aio_stat(fh_or_path,callback=&PL_sv_undef)
813 SV * fh_or_path
814 SV * callback
815 ALIAS:
816 aio_stat = REQ_STAT
817 aio_lstat = REQ_LSTAT
818 CODE:
819 {
820 dREQ;
821
822 New (0, req->statdata, 1, Stat_t);
823 if (!req->statdata)
824 {
825 free_req (req);
826 croak ("out of memory during aio_req->statdata allocation");
827 }
828
829 if (SvPOK (fh_or_path))
830 {
831 req->type = ix;
832 req->data = newSVsv (fh_or_path);
833 req->dataptr = SvPVbyte_nolen (req->data);
834 }
835 else
836 {
837 req->type = REQ_FSTAT;
838 req->fh = newSVsv (fh_or_path);
839 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
840 }
841
842 send_req (req);
843 }
844
845 void
846 aio_unlink(pathname,callback=&PL_sv_undef)
847 SV * pathname
848 SV * callback
849 ALIAS:
850 aio_unlink = REQ_UNLINK
851 aio_rmdir = REQ_RMDIR
852 CODE:
853 {
854 dREQ;
855
856 req->type = ix;
857 req->data = newSVsv (pathname);
858 req->dataptr = SvPVbyte_nolen (req->data);
859
860 send_req (req);
861 }
862
863 void
864 aio_symlink(oldpath,newpath,callback=&PL_sv_undef)
865 SV * oldpath
866 SV * newpath
867 SV * callback
868 CODE:
869 {
870 dREQ;
871
872 req->type = REQ_SYMLINK;
873 req->fh = newSVsv (oldpath);
874 req->data2ptr = SvPVbyte_nolen (req->fh);
875 req->data = newSVsv (newpath);
876 req->dataptr = SvPVbyte_nolen (req->data);
877
878 send_req (req);
879 }
880
881 void
882 flush()
883 PROTOTYPE:
884 CODE:
885 while (nreqs)
886 {
887 poll_wait ();
888 poll_cb ();
889 }
890
891 void
892 poll()
893 PROTOTYPE:
894 CODE:
895 if (nreqs)
896 {
897 poll_wait ();
898 poll_cb ();
899 }
900
901 int
902 poll_fileno()
903 PROTOTYPE:
904 CODE:
905 RETVAL = respipe [0];
906 OUTPUT:
907 RETVAL
908
909 int
910 poll_cb(...)
911 PROTOTYPE:
912 CODE:
913 RETVAL = poll_cb ();
914 OUTPUT:
915 RETVAL
916
917 void
918 poll_wait()
919 PROTOTYPE:
920 CODE:
921 if (nreqs)
922 poll_wait ();
923
924 int
925 nreqs()
926 PROTOTYPE:
927 CODE:
928 RETVAL = nreqs;
929 OUTPUT:
930 RETVAL
931