libpthread/nptl: core of the "Native Posix Threading Library" for uClibc

targetting arm,sh,i386,mips,sparc for now

Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/libpthread/nptl/pthread_mutex_timedlock.c b/libpthread/nptl/pthread_mutex_timedlock.c
new file mode 100644
index 000000000..1cd2c7e60
--- /dev/null
+++ b/libpthread/nptl/pthread_mutex_timedlock.c
@@ -0,0 +1,118 @@
+/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   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 "pthreadP.h"
+#include <lowlevellock.h>
+
+
+int
+pthread_mutex_timedlock (mutex, abstime)
+     pthread_mutex_t *mutex;
+     const struct timespec *abstime;
+{
+  pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
+  int result = 0;
+
+  /* We must not check ABSTIME here.  If the thread does not block
+     abstime must not be checked for a valid value.  */
+
+  switch (mutex->__data.__kind)
+    {
+      /* Recursive mutex.  */
+    case PTHREAD_MUTEX_RECURSIVE_NP:
+      /* Check whether we already hold the mutex.  */
+      if (mutex->__data.__owner == id)
+	{
+	  /* Just bump the counter.  */
+	  if (__builtin_expect (mutex->__data.__count + 1 == 0, 0))
+	    /* Overflow of the counter.  */
+	    return EAGAIN;
+
+	  ++mutex->__data.__count;
+
+	  goto out;
+	}
+      else
+	{
+	  /* We have to get the mutex.  */
+	  result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
+
+	  if (result != 0)
+	    goto out;
+
+	  /* Only locked once so far.  */
+	  mutex->__data.__count = 1;
+	}
+      break;
+
+      /* Error checking mutex.  */
+    case PTHREAD_MUTEX_ERRORCHECK_NP:
+      /* Check whether we already hold the mutex.  */
+      if (mutex->__data.__owner == id)
+	return EDEADLK;
+
+      /* FALLTHROUGH */
+
+    default:
+      /* Correct code cannot set any other type.  */
+    case PTHREAD_MUTEX_TIMED_NP:
+    simple:
+      /* Normal mutex.  */
+      result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
+      break;
+
+    case PTHREAD_MUTEX_ADAPTIVE_NP:
+      if (! __is_smp)
+	goto simple;
+
+      if (lll_mutex_trylock (mutex->__data.__lock) != 0)
+	{
+	  int cnt = 0;
+	  int max_cnt = MIN (MAX_ADAPTIVE_COUNT,
+			     mutex->__data.__spins * 2 + 10);
+	  do
+	    {
+	      if (cnt++ >= max_cnt)
+		{
+		  result = lll_mutex_timedlock (mutex->__data.__lock, abstime);
+		  break;
+		}
+
+#ifdef BUSY_WAIT_NOP
+	      BUSY_WAIT_NOP;
+#endif
+	    }
+	  while (lll_mutex_trylock (mutex->__data.__lock) != 0);
+
+	  mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8;
+	}
+      break;
+    }
+
+  if (result == 0)
+    {
+      /* Record the ownership.  */
+      mutex->__data.__owner = id;
+      ++mutex->__data.__nusers;
+    }
+
+ out:
+  return result;
+}