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-rw-r--r--libpthread/nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c b/libpthread/nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c
new file mode 100644
index 000000000..3830f94da
--- /dev/null
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c
@@ -0,0 +1,114 @@
+/* Copyright (C) 2006, 2007 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Jakub Jelinek <jakub@redhat.com>, 2006.
+
+ 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. */
+
+#include <errno.h>
+#include <sysdep.h>
+#include <lowlevellock.h>
+#include <sys/time.h>
+#include <pthreadP.h>
+
+
+int
+__lll_robust_lock_wait (int *futex, int private)
+{
+ int oldval = *futex;
+ int tid = THREAD_GETMEM (THREAD_SELF, tid);
+
+ /* If the futex changed meanwhile try locking again. */
+ if (oldval == 0)
+ goto try;
+
+ do
+ {
+ if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0))
+ return oldval;
+
+ int newval = oldval | FUTEX_WAITERS;
+ if (oldval != newval
+ && atomic_compare_and_exchange_bool_acq (futex, newval, oldval))
+ continue;
+
+ lll_futex_wait (futex, newval, private);
+
+ try:
+ ;
+ }
+ while ((oldval = atomic_compare_and_exchange_val_acq (futex,
+ tid | FUTEX_WAITERS,
+ 0)) != 0);
+ return 0;
+}
+
+
+int
+__lll_robust_timedlock_wait (int *futex, const struct timespec *abstime,
+ int private)
+{
+ /* Reject invalid timeouts. */
+ if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)
+ return EINVAL;
+
+ int tid = THREAD_GETMEM (THREAD_SELF, tid);
+ int oldval = *futex;
+
+ /* If the futex changed meanwhile try locking again. */
+ if (oldval == 0)
+ goto try;
+
+ do
+ {
+ struct timeval tv;
+ struct timespec rt;
+
+ /* Get the current time. */
+ (void) __gettimeofday (&tv, NULL);
+
+ /* Compute relative timeout. */
+ rt.tv_sec = abstime->tv_sec - tv.tv_sec;
+ rt.tv_nsec = abstime->tv_nsec - tv.tv_usec * 1000;
+ if (rt.tv_nsec < 0)
+ {
+ rt.tv_nsec += 1000000000;
+ --rt.tv_sec;
+ }
+
+ /* Already timed out? */
+ if (rt.tv_sec < 0)
+ return ETIMEDOUT;
+
+ /* Wait. */
+ if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0))
+ return oldval;
+
+ int newval = oldval | FUTEX_WAITERS;
+ if (oldval != newval
+ && atomic_compare_and_exchange_bool_acq (futex, newval, oldval))
+ continue;
+
+ lll_futex_timed_wait (futex, newval, &rt, private);
+
+ try:
+ ;
+ }
+ while ((oldval = atomic_compare_and_exchange_val_acq (futex,
+ tid | FUTEX_WAITERS,
+ 0)) != 0);
+
+ return 0;
+}