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Diffstat (limited to 'rtkaio/sysdeps/unix/sysv/linux/kaio_suspend.c')
-rw-r--r--rtkaio/sysdeps/unix/sysv/linux/kaio_suspend.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/rtkaio/sysdeps/unix/sysv/linux/kaio_suspend.c b/rtkaio/sysdeps/unix/sysv/linux/kaio_suspend.c
new file mode 100644
index 0000000000..2400c5223c
--- /dev/null
+++ b/rtkaio/sysdeps/unix/sysv/linux/kaio_suspend.c
@@ -0,0 +1,327 @@
+/* Suspend until termination of a requests.
+ Copyright (C) 1997, 1998, 1999, 2000, 2002, 2003, 2006
+ Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+
+/* We use an UGLY hack to prevent gcc from finding us cheating. The
+ implementations of aio_suspend and aio_suspend64 are identical and so
+ we want to avoid code duplication by using aliases. But gcc sees
+ the different parameter lists and prints a warning. We define here
+ a function so that aio_suspend64 has no prototype. */
+#define aio_suspend64 XXX
+#include <aio.h>
+/* And undo the hack. */
+#undef aio_suspend64
+
+#include <kaio_misc.h>
+
+#ifndef USE_KAIO
+#include <aio_suspend.c>
+#else
+
+#include <assert.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+#include <bits/libc-lock.h>
+#include <sysdep-cancel.h>
+
+
+struct clparam
+{
+ const struct aiocb *const *list;
+ struct waitlist *waitlist;
+ struct requestlist **requestlist;
+#ifndef DONT_NEED_AIO_MISC_COND
+ pthread_cond_t *cond;
+#endif
+ int nent;
+};
+
+
+static void
+cleanup (void *arg)
+{
+#ifdef DONT_NEED_AIO_MISC_COND
+ /* Acquire the mutex. If pthread_cond_*wait is used this would
+ happen implicitly. */
+ pthread_mutex_lock (&__aio_requests_mutex);
+#endif
+
+ const struct clparam *param = (const struct clparam *) arg;
+
+ /* Now remove the entry in the waiting list for all requests
+ which didn't terminate. */
+ int cnt = param->nent;
+ while (cnt-- > 0)
+ if (param->list[cnt] != NULL
+ && param->list[cnt]->__error_code == EINPROGRESS)
+ {
+ struct waitlist **listp;
+
+ assert (param->requestlist[cnt] != NULL);
+
+ /* There is the chance that we cannot find our entry anymore. This
+ could happen if the request terminated and restarted again. */
+ listp = &param->requestlist[cnt]->waiting;
+ while (*listp != NULL && *listp != &param->waitlist[cnt])
+ listp = &(*listp)->next;
+
+ if (*listp != NULL)
+ *listp = (*listp)->next;
+ }
+
+#ifndef DONT_NEED_AIO_MISC_COND
+ /* Release the conditional variable. */
+ (void) pthread_cond_destroy (param->cond);
+#endif
+
+ /* Release the mutex. */
+ pthread_mutex_unlock (&__aio_requests_mutex);
+}
+
+
+int
+aio_suspend (list, nent, timeout)
+ const struct aiocb *const list[];
+ int nent;
+ const struct timespec *timeout;
+{
+ if (__builtin_expect (nent < 0, 0))
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ struct waitlist waitlist[nent];
+ struct requestlist *requestlist[nent];
+#ifndef DONT_NEED_AIO_MISC_COND
+ pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+#endif
+ int cnt;
+ int result = 0;
+ int cntr = 1;
+ int total = 0, ktotal = 0;
+
+ /* Request the mutex. */
+ pthread_mutex_lock (&__aio_requests_mutex);
+
+ /* There is not yet a finished request. Signal the request that
+ we are working for it. */
+ for (cnt = 0; cnt < nent; ++cnt)
+ if (list[cnt] != NULL)
+ {
+ if (list[cnt]->__error_code == EINPROGRESS)
+ {
+ requestlist[cnt] = __aio_find_req ((aiocb_union *) list[cnt]);
+
+ if (requestlist[cnt] != NULL)
+ {
+#ifndef DONT_NEED_AIO_MISC_COND
+ waitlist[cnt].cond = &cond;
+#endif
+ waitlist[cnt].result = NULL;
+ waitlist[cnt].next = requestlist[cnt]->waiting;
+ waitlist[cnt].counterp = &cntr;
+ waitlist[cnt].sigevp = NULL;
+#ifdef BROKEN_THREAD_SIGNALS
+ waitlist[cnt].caller_pid = 0; /* Not needed. */
+#endif
+ requestlist[cnt]->waiting = &waitlist[cnt];
+ total++;
+ if (requestlist[cnt]->kioctx != KCTX_NONE)
+ ktotal++;
+ }
+ else
+ /* We will never suspend. */
+ break;
+ }
+ else
+ /* We will never suspend. */
+ break;
+ }
+
+
+ /* Only if none of the entries is NULL or finished to be wait. */
+ if (cnt == nent && total)
+ {
+ struct clparam clparam =
+ {
+ .list = list,
+ .waitlist = waitlist,
+ .requestlist = requestlist,
+#ifndef DONT_NEED_AIO_MISC_COND
+ .cond = &cond,
+#endif
+ .nent = nent
+ };
+
+ pthread_cleanup_push (cleanup, &clparam);
+
+ if (!__kernel_thread_started && ktotal)
+ {
+ /* If the kernel aio thread was not started yet all requests
+ are served by the kernel and there are no other threads running,
+ read events with mutex hold, so that nobody else can get them
+ instead of us here. */
+ if (SINGLE_THREAD_P && total == ktotal)
+ {
+ if (timeout == NULL)
+ {
+ while (cntr == 1)
+ __aio_wait_for_events (__aio_kioctx, NULL);
+ }
+ else
+ {
+ struct timeval now;
+ struct timespec abstime, ts;
+
+ __gettimeofday (&now, NULL);
+ abstime.tv_nsec = timeout->tv_nsec + now.tv_usec * 1000;
+ abstime.tv_sec = timeout->tv_sec + now.tv_sec;
+ if (abstime.tv_nsec >= 1000000000)
+ {
+ abstime.tv_nsec -= 1000000000;
+ abstime.tv_sec += 1;
+ }
+
+ for (;;)
+ {
+ result = __aio_wait_for_events (__aio_kioctx, timeout);
+ if (cntr < 1)
+ break;
+ if (result == ETIMEDOUT)
+ break;
+
+ __gettimeofday (&now, NULL);
+ if (now.tv_sec > abstime.tv_sec
+ || (now.tv_sec == abstime.tv_sec
+ && now.tv_usec * 1000 >= abstime.tv_nsec))
+ break;
+
+ ts.tv_nsec = abstime.tv_nsec - now.tv_usec * 1000;
+ ts.tv_sec = abstime.tv_sec - now.tv_sec;
+ if (abstime.tv_nsec < now.tv_usec * 1000)
+ {
+ ts.tv_nsec += 1000000000;
+ ts.tv_sec -= 1;
+ }
+ timeout = &ts;
+ }
+
+ if (cntr < 1)
+ result = 0;
+ else
+ result = ETIMEDOUT;
+ }
+ total = 0;
+ }
+ else if (__aio_create_kernel_thread () < 0)
+ {
+ total = 0;
+ __set_errno (ENOMEM);
+ result = -1;
+ }
+ }
+
+ if (total == 0)
+ /* Suspending was handled above. */
+ ;
+#ifdef DONT_NEED_AIO_MISC_COND
+ else
+ AIO_MISC_WAIT (result, cntr, timeout, 1);
+#else
+ else if (timeout == NULL)
+ result = pthread_cond_wait (&cond, &__aio_requests_mutex);
+ else
+ {
+ /* We have to convert the relative timeout value into an
+ absolute time value with pthread_cond_timedwait expects. */
+ struct timeval now;
+ struct timespec abstime;
+
+ __gettimeofday (&now, NULL);
+ abstime.tv_nsec = timeout->tv_nsec + now.tv_usec * 1000;
+ abstime.tv_sec = timeout->tv_sec + now.tv_sec;
+ if (abstime.tv_nsec >= 1000000000)
+ {
+ abstime.tv_nsec -= 1000000000;
+ abstime.tv_sec += 1;
+ }
+
+ result = pthread_cond_timedwait (&cond, &__aio_requests_mutex,
+ &abstime);
+ }
+#endif
+
+ pthread_cleanup_pop (0);
+ }
+
+ /* Now remove the entry in the waiting list for all requests
+ which didn't terminate. */
+ while (cnt-- > 0)
+ if (list[cnt] != NULL && list[cnt]->__error_code == EINPROGRESS)
+ {
+ struct waitlist **listp;
+
+ assert (requestlist[cnt] != NULL);
+
+ /* There is the chance that we cannot find our entry anymore. This
+ could happen if the request terminated and restarted again. */
+ listp = &requestlist[cnt]->waiting;
+ while (*listp != NULL && *listp != &waitlist[cnt])
+ listp = &(*listp)->next;
+
+ if (*listp != NULL)
+ *listp = (*listp)->next;
+ }
+
+#ifndef DONT_NEED_AIO_MISC_COND
+ /* Release the conditional variable. */
+ if (__builtin_expect (pthread_cond_destroy (&cond) != 0, 0))
+ /* This must never happen. */
+ abort ();
+#endif
+
+ if (result != 0)
+ {
+#ifndef DONT_NEED_AIO_MISC_COND
+ /* An error occurred. Possibly it's ETIMEDOUT. We have to translate
+ the timeout error report of `pthread_cond_timedwait' to the
+ form expected from `aio_suspend'. */
+ if (result == ETIMEDOUT)
+ __set_errno (EAGAIN);
+ else
+#endif
+ __set_errno (result);
+
+ result = -1;
+ }
+
+ /* Release the mutex. */
+ pthread_mutex_unlock (&__aio_requests_mutex);
+
+ return result;
+}
+
+weak_alias (aio_suspend, aio_suspend64)
+#endif
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