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authorad <ad@NetBSD.org>2007-08-16 13:54:16 +0000
committerad <ad@NetBSD.org>2007-08-16 13:54:16 +0000
commitd9adedd76400ff3a3069a7e9f55a78ff6aeb43e8 (patch)
tree4e3cfb7305417e09804e79b93bf94ca7313bc87b /lib/libpthread/pthread_spin.c
parent8423867fa7ce95339fc3981d44d13c064fd8614e (diff)
Trim fat off libpthread internal spinlock operations. Makes a mesurable
improvement across the board.
Diffstat (limited to 'lib/libpthread/pthread_spin.c')
-rw-r--r--lib/libpthread/pthread_spin.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/lib/libpthread/pthread_spin.c b/lib/libpthread/pthread_spin.c
new file mode 100644
index 00000000000..1e7af0ee544
--- /dev/null
+++ b/lib/libpthread/pthread_spin.c
@@ -0,0 +1,139 @@
+/* $NetBSD: pthread_spin.c,v 1.1 2007/08/16 13:54:17 ad Exp $ */
+
+/*-
+ * Copyright (c) 2001, 2006, 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Nathan J. Williams and Andrew Doran.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the NetBSD
+ * Foundation, Inc. and its contributors.
+ * 4. Neither the name of The NetBSD Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * Public (POSIX-specified) spinlocks.
+ */
+
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: pthread_spin.c,v 1.1 2007/08/16 13:54:17 ad Exp $");
+
+#include <sys/types.h>
+#include <sys/lock.h>
+#include <sys/ras.h>
+
+#include <errno.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "pthread.h"
+#include "pthread_int.h"
+
+int
+pthread_spin_init(pthread_spinlock_t *lock, int pshared)
+{
+
+#ifdef ERRORCHECK
+ if (lock == NULL || (pshared != PTHREAD_PROCESS_PRIVATE &&
+ pshared != PTHREAD_PROCESS_SHARED))
+ return EINVAL;
+#endif
+ lock->pts_magic = _PT_SPINLOCK_MAGIC;
+
+ /*
+ * We don't actually use the pshared flag for anything;
+ * CPU simple locks have all the process-shared properties
+ * that we want anyway.
+ */
+ lock->pts_flags = pshared;
+ pthread_lockinit(&lock->pts_spin);
+
+ return 0;
+}
+
+int
+pthread_spin_destroy(pthread_spinlock_t *lock)
+{
+
+#ifdef ERRORCHECK
+ if (lock == NULL || lock->pts_magic != _PT_SPINLOCK_MAGIC)
+ return EINVAL;
+ if (lock->pts_spin != __SIMPLELOCK_UNLOCKED)
+ return EBUSY;
+#endif
+
+ lock->pts_magic = _PT_SPINLOCK_DEAD;
+
+ return 0;
+}
+
+int
+pthread_spin_lock(pthread_spinlock_t *lock)
+{
+
+#ifdef ERRORCHECK
+ if (lock == NULL || lock->pts_magic != _PT_SPINLOCK_MAGIC)
+ return EINVAL;
+#endif
+
+ while (pthread__simple_lock_try(&lock->pts_spin) == 0) {
+ pthread__smt_pause();
+ }
+
+ return 0;
+}
+
+int
+pthread_spin_trylock(pthread_spinlock_t *lock)
+{
+
+#ifdef ERRORCHECK
+ if (lock == NULL || lock->pts_magic != _PT_SPINLOCK_MAGIC)
+ return EINVAL;
+#endif
+
+ if (pthread__simple_lock_try(&lock->pts_spin) == 0)
+ return EBUSY;
+
+ return 0;
+}
+
+int
+pthread_spin_unlock(pthread_spinlock_t *lock)
+{
+
+#ifdef ERRORCHECK
+ if (lock == NULL || lock->pts_magic != _PT_SPINLOCK_MAGIC)
+ return EINVAL;
+#endif
+
+ pthread__simple_unlock(&lock->pts_spin);
+
+ return 0;
+}