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root |
1.1 |
/* |
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* libev linux aio fd activity backend |
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* |
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* Copyright (c) 2019 Marc Alexander Lehmann <libev@schmorp.de> |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without modifica- |
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* tion, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright notice, |
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* this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
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* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
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* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
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* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
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* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- |
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* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* |
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* Alternatively, the contents of this file may be used under the terms of |
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* the GNU General Public License ("GPL") version 2 or any later version, |
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* in which case the provisions of the GPL are applicable instead of |
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* the above. If you wish to allow the use of your version of this file |
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* only under the terms of the GPL and not to allow others to use your |
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* version of this file under the BSD license, indicate your decision |
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* by deleting the provisions above and replace them with the notice |
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* and other provisions required by the GPL. If you do not delete the |
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* provisions above, a recipient may use your version of this file under |
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* either the BSD or the GPL. |
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*/ |
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root |
1.10 |
#define EPOLL_FALLBACK 1 |
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root |
1.1 |
#include <sys/time.h> /* actually linux/time.h, but we must assume they are compatible */ |
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root |
1.2 |
#include <poll.h> |
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root |
1.1 |
#include <linux/aio_abi.h> |
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46 |
root |
1.10 |
#if EPOLL_FALLBACK |
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# include <sys/epoll.h> |
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#endif |
49 |
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root |
1.6 |
/* we try to fill 4kB pages exactly. |
51 |
root |
1.1 |
* the ring buffer header is 32 bytes, every io event is 32 bytes. |
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root |
1.6 |
* the kernel takes the io event number, doubles it, adds 2, adds the ring buffer. |
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root |
1.9 |
* therefore the calculation below will use "exactly" 4kB for the ring buffer |
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root |
1.1 |
*/ |
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root |
1.9 |
#define EV_LINUXAIO_DEPTH (128 / 2 - 2 - 1) /* max. number of io events per batch */ |
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root |
1.1 |
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/*****************************************************************************/ |
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root |
1.20 |
/* syscall wrapdadoop - this section has the raw syscall definitions */ |
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root |
1.1 |
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#include <sys/syscall.h> /* no glibc wrappers */ |
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root |
1.5 |
/* aio_abi.h is not versioned in any way, so we cannot test for its existance */ |
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root |
1.1 |
#define IOCB_CMD_POLL 5 |
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/* taken from linux/fs/aio.c */ |
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#define AIO_RING_MAGIC 0xa10a10a1 |
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#define AIO_RING_INCOMPAT_FEATURES 0 |
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struct aio_ring |
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{ |
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unsigned id; /* kernel internal index number */ |
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unsigned nr; /* number of io_events */ |
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unsigned head; /* Written to by userland or by kernel. */ |
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unsigned tail; |
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unsigned magic; |
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unsigned compat_features; |
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unsigned incompat_features; |
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unsigned header_length; /* size of aio_ring */ |
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struct io_event io_events[0]; |
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}; |
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root |
1.6 |
inline_size |
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int |
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root |
1.20 |
evsys_io_setup (unsigned nr_events, aio_context_t *ctx_idp) |
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root |
1.1 |
{ |
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return syscall (SYS_io_setup, nr_events, ctx_idp); |
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} |
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root |
1.6 |
inline_size |
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int |
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root |
1.20 |
evsys_io_destroy (aio_context_t ctx_id) |
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1.1 |
{ |
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return syscall (SYS_io_destroy, ctx_id); |
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} |
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97 |
root |
1.6 |
inline_size |
98 |
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int |
99 |
root |
1.20 |
evsys_io_submit (aio_context_t ctx_id, long nr, struct iocb *cbp[]) |
100 |
root |
1.1 |
{ |
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return syscall (SYS_io_submit, ctx_id, nr, cbp); |
102 |
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} |
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104 |
root |
1.6 |
inline_size |
105 |
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int |
106 |
root |
1.20 |
evsys_io_cancel (aio_context_t ctx_id, struct iocb *cbp, struct io_event *result) |
107 |
root |
1.1 |
{ |
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return syscall (SYS_io_cancel, ctx_id, cbp, result); |
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} |
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111 |
root |
1.6 |
inline_size |
112 |
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int |
113 |
root |
1.20 |
evsys_io_getevents (aio_context_t ctx_id, long min_nr, long nr, struct io_event *events, struct timespec *timeout) |
114 |
root |
1.1 |
{ |
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return syscall (SYS_io_getevents, ctx_id, min_nr, nr, events, timeout); |
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} |
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/*****************************************************************************/ |
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/* actual backed implementation */ |
120 |
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121 |
root |
1.7 |
/* we use out own wrapper structure in acse we ever want to do something "clever" */ |
122 |
root |
1.1 |
typedef struct aniocb |
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{ |
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struct iocb io; |
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/*int inuse;*/ |
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} *ANIOCBP; |
127 |
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128 |
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inline_size |
129 |
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void |
130 |
root |
1.22 |
linuxaio_array_needsize_iocbp (ANIOCBP *base, int offset, int count) |
131 |
root |
1.1 |
{ |
132 |
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while (count--) |
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{ |
134 |
root |
1.23 |
/* TODO: quite the overhead to allocate every iocb separately, maybe use our own alocator? */ |
135 |
root |
1.22 |
ANIOCBP iocb = (ANIOCBP)ev_malloc (sizeof (*iocb)); |
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137 |
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/* full zero initialise is probably not required at the moment, but |
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* this is not well documented, so we better do it. |
139 |
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*/ |
140 |
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memset (iocb, 0, sizeof (*iocb)); |
141 |
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142 |
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iocb->io.aio_lio_opcode = IOCB_CMD_POLL; |
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iocb->io.aio_data = offset; |
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iocb->io.aio_fildes = offset; |
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146 |
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base [offset++] = iocb; |
147 |
root |
1.1 |
} |
148 |
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} |
149 |
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150 |
root |
1.6 |
ecb_cold |
151 |
root |
1.1 |
static void |
152 |
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linuxaio_free_iocbp (EV_P) |
153 |
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{ |
154 |
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while (linuxaio_iocbpmax--) |
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ev_free (linuxaio_iocbps [linuxaio_iocbpmax]); |
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157 |
root |
1.6 |
linuxaio_iocbpmax = 0; /* next resize will completely reallocate the array, at some overhead */ |
158 |
root |
1.1 |
} |
159 |
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160 |
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static void |
161 |
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linuxaio_modify (EV_P_ int fd, int oev, int nev) |
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{ |
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array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp); |
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root |
1.22 |
ANIOCBP iocb = linuxaio_iocbps [fd]; |
165 |
root |
1.1 |
|
166 |
root |
1.10 |
#if EPOLL_FALLBACK |
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if (iocb->io.aio_reqprio < 0) |
168 |
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{ |
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epoll_ctl (backend_fd, EPOLL_CTL_DEL, fd, 0); |
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iocb->io.aio_reqprio = 0; |
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} |
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#endif |
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174 |
root |
1.1 |
if (iocb->io.aio_buf) |
175 |
root |
1.20 |
evsys_io_cancel (linuxaio_ctx, &iocb->io, (struct io_event *)0); /* always returns an error relevant kernels */ |
176 |
root |
1.1 |
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if (nev) |
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{ |
179 |
root |
1.22 |
iocb->io.aio_buf = |
180 |
root |
1.1 |
(nev & EV_READ ? POLLIN : 0) |
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| (nev & EV_WRITE ? POLLOUT : 0); |
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183 |
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/* queue iocb up for io_submit */ |
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/* this assumes we only ever get one call per fd per loop iteration */ |
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++linuxaio_submitcnt; |
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array_needsize (struct iocb *, linuxaio_submits, linuxaio_submitmax, linuxaio_submitcnt, array_needsize_noinit); |
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linuxaio_submits [linuxaio_submitcnt - 1] = &iocb->io; |
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} |
189 |
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} |
190 |
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191 |
root |
1.19 |
#if EPOLL_FALLBACK |
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193 |
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static void |
194 |
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linuxaio_rearm_epoll (EV_P_ struct iocb *iocb, int op) |
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{ |
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struct epoll_event eev; |
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eev.events = EPOLLONESHOT; |
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if (iocb->aio_buf & POLLIN ) eev.events |= EPOLLIN ; |
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if (iocb->aio_buf & POLLOUT) eev.events |= EPOLLOUT; |
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eev.data.fd = iocb->aio_fildes; |
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203 |
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if (epoll_ctl (backend_fd, op, iocb->aio_fildes, &eev) < 0) |
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ev_syserr ("(libeio) linuxaio epoll_ctl"); |
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} |
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static void |
208 |
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linuxaio_epoll_cb (EV_P_ struct ev_io *w, int revents) |
209 |
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{ |
210 |
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struct epoll_event events[16]; |
211 |
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212 |
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for (;;) |
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{ |
214 |
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int idx; |
215 |
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int res = epoll_wait (backend_fd, events, sizeof (events) / sizeof (events [0]), 0); |
216 |
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217 |
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if (expect_false (res < 0)) |
218 |
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ev_syserr ("(libev) linuxaio epoll_wait"); |
219 |
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else if (!res) |
220 |
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break; |
221 |
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222 |
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for (idx = res; idx--; ) |
223 |
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{ |
224 |
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int fd = events [idx].data.fd; |
225 |
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uint32_t ev = events [idx].events; |
226 |
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227 |
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assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdmax)); |
228 |
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229 |
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linuxaio_rearm_epoll (EV_A_ &linuxaio_iocbps [fd]->io, EPOLL_CTL_MOD); |
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231 |
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fd_event (EV_A_ fd, |
232 |
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(ev & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0) |
233 |
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| (ev & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0)); |
234 |
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} |
235 |
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236 |
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if (res < sizeof (events) / sizeof (events [0])) |
237 |
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break; |
238 |
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} |
239 |
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} |
240 |
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241 |
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#endif |
242 |
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243 |
root |
1.1 |
static void |
244 |
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linuxaio_parse_events (EV_P_ struct io_event *ev, int nr) |
245 |
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{ |
246 |
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while (nr) |
247 |
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{ |
248 |
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int fd = ev->data; |
249 |
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int res = ev->res; |
250 |
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251 |
root |
1.2 |
assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdmax)); |
252 |
root |
1.1 |
|
253 |
root |
1.19 |
/* linux aio is oneshot: rearm fd. TODO: this does more work than needed */ |
254 |
root |
1.1 |
linuxaio_iocbps [fd]->io.aio_buf = 0; |
255 |
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anfds [fd].events = 0; |
256 |
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fd_change (EV_A_ fd, 0); |
257 |
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258 |
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/* feed events, we do not expect or handle POLLNVAL */ |
259 |
root |
1.21 |
fd_event ( |
260 |
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EV_A_ |
261 |
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fd, |
262 |
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(res & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0) |
263 |
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| (res & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0) |
264 |
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); |
265 |
root |
1.1 |
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266 |
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--nr; |
267 |
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++ev; |
268 |
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} |
269 |
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} |
270 |
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271 |
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/* get any events from ringbuffer, return true if any were handled */ |
272 |
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static int |
273 |
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linuxaio_get_events_from_ring (EV_P) |
274 |
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{ |
275 |
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struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx; |
276 |
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277 |
root |
1.13 |
/* the kernel reads and writes both of these variables, */ |
278 |
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/* as a C extension, we assume that volatile use here */ |
279 |
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/* both makes reads atomic and once-only */ |
280 |
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unsigned head = *(volatile unsigned *)&ring->head; |
281 |
root |
1.1 |
unsigned tail = *(volatile unsigned *)&ring->tail; |
282 |
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283 |
root |
1.6 |
if (head == tail) |
284 |
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return 0; |
285 |
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286 |
root |
1.7 |
/* bail out if the ring buffer doesn't match the expected layout */ |
287 |
root |
1.17 |
if (expect_false (ring->magic != AIO_RING_MAGIC) |
288 |
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|| ring->incompat_features != AIO_RING_INCOMPAT_FEATURES |
289 |
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|| ring->header_length != sizeof (struct aio_ring)) /* TODO: or use it to find io_event[0]? */ |
290 |
root |
1.1 |
return 0; |
291 |
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292 |
root |
1.12 |
/* make sure the events up to tail are visible */ |
293 |
root |
1.9 |
ECB_MEMORY_FENCE_ACQUIRE; |
294 |
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295 |
root |
1.1 |
/* parse all available events, but only once, to avoid starvation */ |
296 |
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if (tail > head) /* normal case around */ |
297 |
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linuxaio_parse_events (EV_A_ ring->io_events + head, tail - head); |
298 |
root |
1.6 |
else /* wrapped around */ |
299 |
root |
1.1 |
{ |
300 |
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linuxaio_parse_events (EV_A_ ring->io_events + head, ring->nr - head); |
301 |
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linuxaio_parse_events (EV_A_ ring->io_events, tail); |
302 |
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} |
303 |
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304 |
root |
1.16 |
/* TODO: we only need a compiler barrier here, not a read fence */ |
305 |
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ECB_MEMORY_FENCE_RELEASE; |
306 |
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/* as an extension to C, we hope that the volatile will make this atomic and once-only */ |
307 |
root |
1.11 |
*(volatile unsigned *)&ring->head = tail; |
308 |
root |
1.12 |
/* make sure kernel can see our new head value - probably not required */ |
309 |
root |
1.11 |
ECB_MEMORY_FENCE_RELEASE; |
310 |
root |
1.1 |
|
311 |
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return 1; |
312 |
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} |
313 |
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314 |
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/* read at least one event from kernel, or timeout */ |
315 |
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inline_size |
316 |
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void |
317 |
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linuxaio_get_events (EV_P_ ev_tstamp timeout) |
318 |
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{ |
319 |
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struct timespec ts; |
320 |
root |
1.18 |
struct io_event ioev[1]; |
321 |
root |
1.1 |
int res; |
322 |
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323 |
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if (linuxaio_get_events_from_ring (EV_A)) |
324 |
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return; |
325 |
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326 |
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/* no events, so wait for at least one, then poll ring buffer again */ |
327 |
root |
1.7 |
/* this degrades to one event per loop iteration */ |
328 |
root |
1.1 |
/* if the ring buffer changes layout, but so be it */ |
329 |
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|
330 |
root |
1.19 |
EV_RELEASE_CB; |
331 |
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|
332 |
root |
1.1 |
ts.tv_sec = (long)timeout; |
333 |
|
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ts.tv_nsec = (long)((timeout - ts.tv_sec) * 1e9); |
334 |
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|
335 |
root |
1.20 |
res = evsys_io_getevents (linuxaio_ctx, 1, sizeof (ioev) / sizeof (ioev [0]), ioev, &ts); |
336 |
root |
1.1 |
|
337 |
root |
1.19 |
EV_ACQUIRE_CB; |
338 |
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|
339 |
root |
1.1 |
if (res < 0) |
340 |
root |
1.10 |
if (errno == EINTR) |
341 |
|
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/* ignored */; |
342 |
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else |
343 |
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ev_syserr ("(libev) linuxaio io_getevents"); |
344 |
root |
1.1 |
else if (res) |
345 |
|
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{ |
346 |
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/* at least one event received, handle it and any remaining ones in the ring buffer */ |
347 |
root |
1.18 |
linuxaio_parse_events (EV_A_ ioev, res); |
348 |
root |
1.1 |
linuxaio_get_events_from_ring (EV_A); |
349 |
|
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} |
350 |
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} |
351 |
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352 |
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static void |
353 |
|
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linuxaio_poll (EV_P_ ev_tstamp timeout) |
354 |
|
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{ |
355 |
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int submitted; |
356 |
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|
357 |
|
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/* first phase: submit new iocbs */ |
358 |
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359 |
|
|
/* io_submit might return less than the requested number of iocbs */ |
360 |
|
|
/* this is, afaics, only because of errors, but we go by the book and use a loop, */ |
361 |
|
|
/* which allows us to pinpoint the errornous iocb */ |
362 |
|
|
for (submitted = 0; submitted < linuxaio_submitcnt; ) |
363 |
|
|
{ |
364 |
root |
1.19 |
#if 0 |
365 |
|
|
int res; |
366 |
|
|
if (linuxaio_submits[submitted]->aio_fildes == backend_fd) |
367 |
root |
1.20 |
res = evsys_io_submit (linuxaio_ctx, 1, linuxaio_submits + submitted); |
368 |
root |
1.19 |
else |
369 |
|
|
{ res = -1; errno = EINVAL; }; |
370 |
|
|
#else |
371 |
root |
1.20 |
int res = evsys_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted); |
372 |
root |
1.19 |
#endif |
373 |
root |
1.1 |
|
374 |
root |
1.17 |
if (expect_false (res < 0)) |
375 |
root |
1.1 |
if (errno == EAGAIN) |
376 |
|
|
{ |
377 |
|
|
/* This happens when the ring buffer is full, at least. I assume this means |
378 |
|
|
* that the event was queued synchronously during io_submit, and thus |
379 |
root |
1.10 |
* the buffer overflowed. |
380 |
|
|
* In this case, we just try in next loop iteration. |
381 |
root |
1.7 |
* This should not result in a few fds taking priority, as the interface |
382 |
|
|
* is one-shot, and we submit iocb's in a round-robin fashion. |
383 |
root |
1.19 |
* TODO: maybe make "submitted" persistent, so we don't have to memmove? |
384 |
root |
1.1 |
*/ |
385 |
root |
1.19 |
if (ecb_expect_false (submitted)) |
386 |
|
|
{ |
387 |
|
|
memmove (linuxaio_submits, linuxaio_submits + submitted, (linuxaio_submitcnt - submitted) * sizeof (*linuxaio_submits)); |
388 |
|
|
linuxaio_submitcnt -= submitted; |
389 |
|
|
} |
390 |
|
|
|
391 |
root |
1.1 |
timeout = 0; |
392 |
|
|
break; |
393 |
|
|
} |
394 |
root |
1.10 |
#if EPOLL_FALLBACK |
395 |
|
|
else if (errno == EINVAL) |
396 |
|
|
{ |
397 |
root |
1.15 |
/* This happens for unsupported fds, officially, but in my testing, |
398 |
root |
1.10 |
* also randomly happens for supported fds. We fall back to good old |
399 |
|
|
* poll() here, under the assumption that this is a very rare case. |
400 |
root |
1.19 |
* See https://lore.kernel.org/patchwork/patch/1047453/ to see |
401 |
|
|
* discussion about such a case (ttys) where polling for POLLIN |
402 |
|
|
* fails but POLLIN|POLLOUT works. |
403 |
root |
1.10 |
*/ |
404 |
|
|
struct iocb *iocb = linuxaio_submits [submitted]; |
405 |
|
|
|
406 |
root |
1.21 |
linuxaio_rearm_epoll (EV_A_ linuxaio_submits [submitted], EPOLL_CTL_ADD); |
407 |
root |
1.10 |
iocb->aio_reqprio = -1; /* mark iocb as epoll */ |
408 |
root |
1.21 |
|
409 |
|
|
res = 1; /* skip this iocb */ |
410 |
root |
1.10 |
} |
411 |
|
|
#endif |
412 |
root |
1.21 |
else if (errno == EBADF) |
413 |
|
|
{ |
414 |
|
|
fd_kill (EV_A_ linuxaio_submits [submitted]->aio_fildes); |
415 |
|
|
|
416 |
|
|
res = 1; /* skip this iocb */ |
417 |
|
|
} |
418 |
root |
1.1 |
else |
419 |
root |
1.8 |
ev_syserr ("(libev) linuxaio io_submit"); |
420 |
root |
1.1 |
|
421 |
|
|
submitted += res; |
422 |
|
|
} |
423 |
|
|
|
424 |
|
|
linuxaio_submitcnt = 0; |
425 |
|
|
|
426 |
|
|
/* second phase: fetch and parse events */ |
427 |
|
|
|
428 |
|
|
linuxaio_get_events (EV_A_ timeout); |
429 |
|
|
} |
430 |
|
|
|
431 |
|
|
inline_size |
432 |
|
|
int |
433 |
|
|
linuxaio_init (EV_P_ int flags) |
434 |
|
|
{ |
435 |
|
|
/* would be great to have a nice test for IOCB_CMD_POLL instead */ |
436 |
root |
1.2 |
/* also: test some semi-common fd types, such as files and ttys in recommended_backends */ |
437 |
root |
1.15 |
#if EPOLL_FALLBACK |
438 |
|
|
/* 4.19 made epoll work */ |
439 |
|
|
if (ev_linux_version () < 0x041300) |
440 |
|
|
return 0; |
441 |
|
|
#else |
442 |
|
|
/* 4.18 introduced IOCB_CMD_POLL */ |
443 |
|
|
if (ev_linux_version () < 0x041200) |
444 |
root |
1.1 |
return 0; |
445 |
root |
1.15 |
#endif |
446 |
root |
1.1 |
|
447 |
root |
1.3 |
linuxaio_ctx = 0; |
448 |
root |
1.20 |
if (evsys_io_setup (EV_LINUXAIO_DEPTH, &linuxaio_ctx) < 0) |
449 |
root |
1.1 |
return 0; |
450 |
|
|
|
451 |
root |
1.10 |
#if EPOLL_FALLBACK |
452 |
|
|
backend_fd = ev_epoll_create (); |
453 |
|
|
if (backend_fd < 0) |
454 |
|
|
{ |
455 |
root |
1.20 |
evsys_io_destroy (linuxaio_ctx); |
456 |
root |
1.10 |
return 0; |
457 |
|
|
} |
458 |
|
|
|
459 |
|
|
ev_io_init (EV_A_ &linuxaio_epoll_w, linuxaio_epoll_cb, backend_fd, EV_READ); |
460 |
root |
1.19 |
ev_set_priority (&linuxaio_epoll_w, EV_MAXPRI); |
461 |
root |
1.10 |
ev_io_start (EV_A_ &linuxaio_epoll_w); |
462 |
root |
1.14 |
ev_unref (EV_A); /* watcher should not keep loop alive */ |
463 |
root |
1.10 |
#endif |
464 |
|
|
|
465 |
root |
1.1 |
backend_modify = linuxaio_modify; |
466 |
|
|
backend_poll = linuxaio_poll; |
467 |
|
|
|
468 |
|
|
linuxaio_iocbpmax = 0; |
469 |
|
|
linuxaio_iocbps = 0; |
470 |
|
|
|
471 |
|
|
linuxaio_submits = 0; |
472 |
|
|
linuxaio_submitmax = 0; |
473 |
|
|
linuxaio_submitcnt = 0; |
474 |
|
|
|
475 |
|
|
return EVBACKEND_LINUXAIO; |
476 |
|
|
} |
477 |
|
|
|
478 |
|
|
inline_size |
479 |
|
|
void |
480 |
|
|
linuxaio_destroy (EV_P) |
481 |
|
|
{ |
482 |
root |
1.10 |
#if EPOLL_FALLBACK |
483 |
|
|
close (backend_fd); |
484 |
|
|
#endif |
485 |
root |
1.1 |
linuxaio_free_iocbp (EV_A); |
486 |
root |
1.21 |
evsys_io_destroy (linuxaio_ctx); |
487 |
root |
1.1 |
} |
488 |
|
|
|
489 |
|
|
inline_size |
490 |
|
|
void |
491 |
|
|
linuxaio_fork (EV_P) |
492 |
|
|
{ |
493 |
root |
1.6 |
/* this frees all iocbs, which is very heavy-handed */ |
494 |
root |
1.2 |
linuxaio_destroy (EV_A); |
495 |
root |
1.6 |
linuxaio_submitcnt = 0; /* all pointers were invalidated */ |
496 |
root |
1.2 |
|
497 |
root |
1.3 |
linuxaio_ctx = 0; |
498 |
root |
1.20 |
while (evsys_io_setup (EV_LINUXAIO_DEPTH, &linuxaio_ctx) < 0) |
499 |
root |
1.8 |
ev_syserr ("(libev) linuxaio io_setup"); |
500 |
root |
1.2 |
|
501 |
root |
1.10 |
#if EPOLL_FALLBACK |
502 |
|
|
while ((backend_fd = ev_epoll_create ()) < 0) |
503 |
|
|
ev_syserr ("(libev) linuxaio epoll_create"); |
504 |
|
|
|
505 |
|
|
ev_io_stop (EV_A_ &linuxaio_epoll_w); |
506 |
|
|
ev_io_init (EV_A_ &linuxaio_epoll_w, linuxaio_epoll_cb, backend_fd, EV_READ); |
507 |
|
|
ev_io_start (EV_A_ &linuxaio_epoll_w); |
508 |
|
|
#endif |
509 |
|
|
|
510 |
root |
1.2 |
fd_rearm_all (EV_A); |
511 |
root |
1.1 |
} |
512 |
|
|
|