Linux-AIO/AIO.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sched.h>

#define STACKSIZE 1024 /* yeah */

enum { REQ_QUIT, REQ_READ, REQ_WRITE, REQ_OPEN };

typedef struct {
  char stack[STACKSIZE];
} aio_thread;

typedef struct {
  int type;
  aio_thread *thread;

/* read/write */
  int fd;
  off_t offset;
  size_t length;
  ssize_t result;
  mode_t mode; /* open */
  int errorno;
  SV *data, *callback;
  void *dataptr;
  STRLEN dataoffset;
} aio_cb;

typedef aio_cb *aio_req;

static int started;
static int nreqs;
static int reqpipe[2], respipe[2];

static int aio_proc(void *arg);

static void
start_thread(void)
{
  aio_thread *thr;

  New (0, thr, 1, aio_thread);

  if (clone (aio_proc,
             &(thr->stack[STACKSIZE]),
             CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND,
             thr) >= 0)
    started++;
  else
    Safefree (thr);
}

static void
end_thread(void)
{
  aio_req req;
  New (0, req, 1, aio_cb);
  req->type = REQ_QUIT;
  write (reqpipe[1], &req, sizeof (aio_req));
}

static void
send_req (aio_req req)
{
  nreqs++;
  write (reqpipe[1], &req, sizeof (aio_req));
}

static void
read_write (pTHX_ int dowrite, int fd, off_t offset, size_t length,
            SV *data, STRLEN dataoffset, SV*callback)
{
  aio_req req;
  STRLEN svlen;
  char *svptr = SvPV (data, svlen);

  if (dataoffset < 0)
    dataoffset += svlen;

  if (dataoffset < 0 || dataoffset > svlen)
    croak ("data offset outside of string");

  if (dowrite)
    {
      /* write: check length and adjust. */
      if (length < 0 || length + dataoffset > svlen)
        length = svlen - dataoffset;
    }
  else
    {
      /* read: grow scalar as necessary */
      svptr = SvGROW (data, length + dataoffset);
    }

  if (length < 0)
    croak ("length must not be negative");

  New (0, req, 1, aio_cb);

  if (!req)
    croak ("out of memory during aio_req allocation");

  req->type = dowrite ? REQ_WRITE : REQ_READ;
  req->fd = fd;
  req->offset = offset;
  req->length = length;
  req->data = SvREFCNT_inc (data);
  req->dataptr = (char *)svptr + dataoffset;
  req->callback = SvREFCNT_inc (callback);

  send_req (req);
}

static int
poll_cb (pTHX)
{
  dSP;
  int count = 0;
  aio_req req;

  while (read (respipe[0], (void *)&req, sizeof (req)) == sizeof (req))
    {
      if (req->type == REQ_QUIT)
        {
          Safefree (req->thread);
          started--;
        }
      else
        {
          int errorno = errno;
          errno = req->errorno;

          if (req->type == REQ_READ)
            SvCUR_set (req->data, req->dataoffset
                                  + req->result > 0 ? req->result : 0);

          PUSHMARK (SP);
          XPUSHs (sv_2mortal (newSViv (req->result)));
          PUTBACK;
          call_sv (req->callback, G_VOID);
          SPAGAIN;
          
          SvREFCNT_dec (req->data);
          SvREFCNT_dec (req->callback);

          errno = errorno;
          nreqs--;
          count++;
        }

      Safefree (req);
    }

  return count;
}

static sigset_t fullsigset;

#undef errno
#include <asm/unistd.h>

static int
aio_proc(void *thr_arg)
{
  aio_thread *thr = thr_arg;
  int sig;
  int errno;
  aio_req req;

  sigprocmask (SIG_SETMASK, &fullsigset, 0);

  /* we rely on gcc's ability to create closures. */
  _syscall3(int,lseek,int,fd,off_t,offset,int,whence);
  _syscall3(int,read,int,fd,char *,buf,off_t,count);
  _syscall3(int,write,int,fd,char *,buf,off_t,count);
  _syscall3(int,open,char *,pathname,int,flags,mode_t,mode);

  /* then loop */
  while (read (reqpipe[0], (void *)&req, sizeof (req)) == sizeof (req))
    {
      req->thread = thr;
      errno = 0;

      if (req->type == REQ_READ || req->type == REQ_WRITE)
        {
          if (lseek (req->fd, req->offset, SEEK_SET) == req->offset)
            {
              if (req->type == REQ_READ)
                req->result = read (req->fd, req->dataptr, req->length);
              else
                req->result = write(req->fd, req->dataptr, req->length);
            }
        }
      else if (req->type == REQ_OPEN)
        {
          req->result = open (req->dataptr, req->fd, req->mode);
        }
      else
        {
          write (respipe[1], (void *)&req, sizeof (req));
          break;
        }

      req->errorno = errno;
      write (respipe[1], (void *)&req, sizeof (req));
    }

  return 0;
}

MODULE = Linux::AIO                PACKAGE = Linux::AIO

BOOT:
{
        sigfillset (&fullsigset);

        if (pipe (reqpipe) || pipe (respipe))
          croak ("unable to initialize request or result pipe");

        if (fcntl (respipe[0], F_SETFL, O_NONBLOCK))
          croak ("cannot set result pipe to nonblocking mode");
}

void
min_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $
        CODE:
        while (nthreads > started)
          start_thread ();

void
max_parallel(nthreads)
        int     nthreads
        PROTOTYPE: $
        CODE:
        int cur = started;
        while (cur > nthreads)
          {          
            end_thread ();
            cur--;
          }

        poll_cb ();
        while (started > nthreads)
          {
            sched_yield ();
            poll_cb ();
          }

void
aio_read(fh,offset,length,data,dataoffset,callback)
        PerlIO *        fh
        UV              offset
        STRLEN          length
        SV *            data
        STRLEN          dataoffset
        SV *            callback
        PROTOTYPE: $$$$$$
        ALIAS:
          aio_write = 1
        CODE:
        SvUPGRADE (data, SVt_PV);
        SvPOK_on (data);
        read_write (aTHX_ ix, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);

void
aio_open(pathname,flags,mode,callback)
        char *  pathname
        int     flags
        int     mode
        SV *    callback
        PROTOTYPE: $$$$
        CODE:
        aio_req req;

        New (0, req, 1, aio_cb);

        if (!req)
          croak ("out of memory during aio_req allocation");

        req->type = REQ_OPEN;
        req->dataptr = pathname;
        req->fd = flags;
        req->mode = mode;
        req->callback = SvREFCNT_inc (callback);

        send_req (req);

int
poll_fileno()
        PROTOTYPE:
        CODE:
        RETVAL = respipe[0];
        OUTPUT:
        RETVAL

int
poll_cb(...)
        PROTOTYPE:
        CODE:
        RETVAL = poll_cb (aTHX);
        OUTPUT:
        RETVAL

int
nreqs()
        PROTOTYPE:
        CODE:
        RETVAL = nreqs;
        OUTPUT:
        RETVAL

Revision:	1.8
Committed:	Thu Aug 16 02:43:46 2001 UTC (22 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.7:	+48 -17 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include "EXTERN.h"
2			#include "perl.h"
3			#include "XSUB.h"
4
5			#include <sys/types.h>
6			#include <unistd.h>
7	root	1.5	#include <fcntl.h>
8	root	1.8	#include <signal.h>
9	root	1.1	#include <sched.h>
10
11	root	1.8	#define STACKSIZE 1024 /* yeah */
12	root	1.1
13	root	1.8	enum { REQ_QUIT, REQ_READ, REQ_WRITE, REQ_OPEN };
14	root	1.1
15			typedef struct {
16			char stack[STACKSIZE];
17			} aio_thread;
18
19			typedef struct {
20			int type;
21			aio_thread *thread;
22
23			/* read/write */
24			int fd;
25			off_t offset;
26			size_t length;
27	root	1.2	ssize_t result;
28	root	1.8	mode_t mode; /* open */
29	root	1.1	int errorno;
30	root	1.5	SV data, callback;
31	root	1.1	void *dataptr;
32	root	1.2	STRLEN dataoffset;
33	root	1.1	} aio_cb;
34
35			typedef aio_cb *aio_req;
36
37			static int started;
38	root	1.5	static int nreqs;
39	root	1.1	static int reqpipe[2], respipe[2];
40
41	root	1.2	static int aio_proc(void *arg);
42
43	root	1.1	static void
44			start_thread(void)
45			{
46	root	1.2	aio_thread *thr;
47
48			New (0, thr, 1, aio_thread);
49
50			if (clone (aio_proc,
51			&(thr->stack[STACKSIZE]),
52			CLONE_VM\|CLONE_FS\|CLONE_FILES\|CLONE_SIGHAND,
53			thr) >= 0)
54			started++;
55			else
56			Safefree (thr);
57	root	1.1	}
58
59			static void
60			end_thread(void)
61			{
62	root	1.5	aio_req req;
63			New (0, req, 1, aio_cb);
64			req->type = REQ_QUIT;
65	root	1.1	write (reqpipe[1], &req, sizeof (aio_req));
66	root	1.2	}
67
68			static void
69	root	1.8	send_req (aio_req req)
70			{
71			nreqs++;
72			write (reqpipe[1], &req, sizeof (aio_req));
73			}
74
75			static void
76	root	1.5	read_write (pTHX_ int dowrite, int fd, off_t offset, size_t length,
77			SV data, STRLEN dataoffset, SVcallback)
78	root	1.2	{
79	root	1.5	aio_req req;
80			STRLEN svlen;
81			char *svptr = SvPV (data, svlen);
82
83			if (dataoffset < 0)
84			dataoffset += svlen;
85
86			if (dataoffset < 0 \|\| dataoffset > svlen)
87			croak ("data offset outside of string");
88
89			if (dowrite)
90			{
91			/* write: check length and adjust. */
92			if (length < 0 \|\| length + dataoffset > svlen)
93			length = svlen - dataoffset;
94			}
95			else
96			{
97			/* read: grow scalar as necessary */
98			svptr = SvGROW (data, length + dataoffset);
99			}
100
101			if (length < 0)
102			croak ("length must not be negative");
103
104			New (0, req, 1, aio_cb);
105
106			if (!req)
107			croak ("out of memory during aio_req allocation");
108
109			req->type = dowrite ? REQ_WRITE : REQ_READ;
110			req->fd = fd;
111			req->offset = offset;
112			req->length = length;
113			req->data = SvREFCNT_inc (data);
114	root	1.6	req->dataptr = (char *)svptr + dataoffset;
115	root	1.5	req->callback = SvREFCNT_inc (callback);
116
117	root	1.8	send_req (req);
118	root	1.5	}
119
120			static int
121			poll_cb (pTHX)
122			{
123			dSP;
124			int count = 0;
125			aio_req req;
126
127			while (read (respipe[0], (void *)&req, sizeof (req)) == sizeof (req))
128			{
129			if (req->type == REQ_QUIT)
130			{
131			Safefree (req->thread);
132			started--;
133			}
134			else
135			{
136			int errorno = errno;
137			errno = req->errorno;
138
139			if (req->type == REQ_READ)
140	root	1.6	SvCUR_set (req->data, req->dataoffset
141			+ req->result > 0 ? req->result : 0);
142	root	1.5
143			PUSHMARK (SP);
144			XPUSHs (sv_2mortal (newSViv (req->result)));
145			PUTBACK;
146			call_sv (req->callback, G_VOID);
147			SPAGAIN;
148
149			SvREFCNT_dec (req->data);
150			SvREFCNT_dec (req->callback);
151
152			errno = errorno;
153			nreqs--;
154			count++;
155			}
156
157			Safefree (req);
158			}
159
160			return count;
161	root	1.2	}
162
163	root	1.8	static sigset_t fullsigset;
164
165	root	1.2	#undef errno
166			#include <asm/unistd.h>
167
168			static int
169			aio_proc(void *thr_arg)
170			{
171			aio_thread *thr = thr_arg;
172			int sig;
173			int errno;
174			aio_req req;
175
176	root	1.8	sigprocmask (SIG_SETMASK, &fullsigset, 0);
177
178	root	1.2	/* we rely on gcc's ability to create closures. */
179			_syscall3(int,lseek,int,fd,off_t,offset,int,whence);
180			_syscall3(int,read,int,fd,char *,buf,off_t,count);
181			_syscall3(int,write,int,fd,char *,buf,off_t,count);
182	root	1.8	_syscall3(int,open,char *,pathname,int,flags,mode_t,mode);
183	root	1.2
184			/* then loop */
185			while (read (reqpipe[0], (void *)&req, sizeof (req)) == sizeof (req))
186			{
187			req->thread = thr;
188	root	1.8	errno = 0;
189	root	1.2
190			if (req->type == REQ_READ \|\| req->type == REQ_WRITE)
191			{
192			if (lseek (req->fd, req->offset, SEEK_SET) == req->offset)
193			{
194			if (req->type == REQ_READ)
195			req->result = read (req->fd, req->dataptr, req->length);
196			else
197			req->result = write(req->fd, req->dataptr, req->length);
198			}
199	root	1.8	}
200			else if (req->type == REQ_OPEN)
201			{
202			req->result = open (req->dataptr, req->fd, req->mode);
203	root	1.2	}
204			else
205			{
206			write (respipe[1], (void *)&req, sizeof (req));
207			break;
208			}
209
210	root	1.8	req->errorno = errno;
211	root	1.2	write (respipe[1], (void *)&req, sizeof (req));
212			}
213
214			return 0;
215	root	1.1	}
216
217			MODULE = Linux::AIO PACKAGE = Linux::AIO
218
219			BOOT:
220			{
221	root	1.8	sigfillset (&fullsigset);
222
223	root	1.1	if (pipe (reqpipe) \|\| pipe (respipe))
224			croak ("unable to initialize request or result pipe");
225	root	1.5
226			if (fcntl (respipe[0], F_SETFL, O_NONBLOCK))
227			croak ("cannot set result pipe to nonblocking mode");
228	root	1.1	}
229
230			void
231			min_parallel(nthreads)
232			int nthreads
233	root	1.5	PROTOTYPE: $
234	root	1.1	CODE:
235			while (nthreads > started)
236			start_thread ();
237
238			void
239			max_parallel(nthreads)
240			int nthreads
241	root	1.5	PROTOTYPE: $
242	root	1.1	CODE:
243	root	1.5	int cur = started;
244			while (cur > nthreads)
245			{
246			end_thread ();
247			cur--;
248			}
249
250			poll_cb ();
251	root	1.1	while (started > nthreads)
252	root	1.5	{
253			sched_yield ();
254			poll_cb ();
255			}
256	root	1.1
257			void
258	root	1.5	aio_read(fh,offset,length,data,dataoffset,callback)
259			PerlIO * fh
260	root	1.6	UV offset
261			STRLEN length
262	root	1.5	SV * data
263			STRLEN dataoffset
264			SV * callback
265			PROTOTYPE: $$$$$$
266	root	1.3	ALIAS:
267	root	1.5	aio_write = 1
268	root	1.1	CODE:
269	root	1.6	SvUPGRADE (data, SVt_PV);
270			SvPOK_on (data);
271	root	1.5	read_write (aTHX_ ix, PerlIO_fileno (fh), offset, length, data, dataoffset, callback);
272	root	1.8
273			void
274			aio_open(pathname,flags,mode,callback)
275			char * pathname
276			int flags
277			int mode
278			SV * callback
279			PROTOTYPE: $$$$
280			CODE:
281			aio_req req;
282
283			New (0, req, 1, aio_cb);
284
285			if (!req)
286			croak ("out of memory during aio_req allocation");
287
288			req->type = REQ_OPEN;
289			req->dataptr = pathname;
290			req->fd = flags;
291			req->mode = mode;
292			req->callback = SvREFCNT_inc (callback);
293
294			send_req (req);
295	root	1.5
296			int
297			poll_fileno()
298			PROTOTYPE:
299			CODE:
300			RETVAL = respipe[0];
301			OUTPUT:
302			RETVAL
303
304			int
305	root	1.6	poll_cb(...)
306	root	1.5	PROTOTYPE:
307			CODE:
308			RETVAL = poll_cb (aTHX);
309			OUTPUT:
310			RETVAL
311
312			int
313			nreqs()
314			PROTOTYPE:
315			CODE:
316			RETVAL = nreqs;
317			OUTPUT:
318			RETVAL
319