--- /dev/null
+#ifndef _URCU_MB_STATIC_H
+#define _URCU_MB_STATIC_H
+
+/*
+ * urcu-mb-static.h
+ *
+ * Userspace RCU header.
+ *
+ * TO BE INCLUDED ONLY IN CODE THAT IS TO BE RECOMPILED ON EACH LIBURCU
+ * RELEASE. See urcu.h for linking dynamically with the userspace rcu library.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
+ *
+ * This 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.
+ *
+ * This 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * IBM's contributions to this file may be relicensed under LGPLv2 or later.
+ */
+
+#include <stdlib.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <stdint.h>
+
+#include <urcu/config.h>
+#include <urcu/compiler.h>
+#include <urcu/arch.h>
+#include <urcu/system.h>
+#include <urcu/uatomic.h>
+#include <urcu/list.h>
+#include <urcu/futex.h>
+#include <urcu/tls-compat.h>
+#include <urcu/debug.h>
+#include <urcu/static/urcu-common.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * This code section can only be included in LGPL 2.1 compatible source code.
+ * See below for the function call wrappers which can be used in code meant to
+ * be only linked with the Userspace RCU library. This comes with a small
+ * performance degradation on the read-side due to the added function calls.
+ * This is required to permit relinking with newer versions of the library.
+ */
+
+extern struct urcu_gp urcu_mb_gp;
+
+extern DECLARE_URCU_TLS(struct urcu_reader, urcu_mb_reader);
+
+/*
+ * Helper for _urcu_mb_read_lock(). The format of urcu_mb_gp.ctr (as well as
+ * the per-thread rcu_reader.ctr) has the upper bits containing a count of
+ * _urcu_mb_read_lock() nesting, and a lower-order bit that contains either zero
+ * or URCU_GP_CTR_PHASE. The cmm_smp_mb() ensures that the accesses in
+ * _urcu_mb_read_lock() happen before the subsequent read-side critical section.
+ */
+static inline void _urcu_mb_read_lock_update(unsigned long tmp)
+{
+ if (caa_likely(!(tmp & URCU_GP_CTR_NEST_MASK))) {
+ _CMM_STORE_SHARED(URCU_TLS(urcu_mb_reader).ctr, _CMM_LOAD_SHARED(urcu_mb_gp.ctr));
+ cmm_smp_mb();
+ } else
+ _CMM_STORE_SHARED(URCU_TLS(urcu_mb_reader).ctr, tmp + URCU_GP_COUNT);
+}
+
+/*
+ * Enter an RCU read-side critical section.
+ *
+ * The first cmm_barrier() call ensures that the compiler does not reorder
+ * the body of _urcu_mb_read_lock() with a mutex.
+ *
+ * This function and its helper are both less than 10 lines long. The
+ * intent is that this function meets the 10-line criterion in LGPL,
+ * allowing this function to be invoked directly from non-LGPL code.
+ */
+static inline void _urcu_mb_read_lock(void)
+{
+ unsigned long tmp;
+
+ urcu_assert(URCU_TLS(urcu_mb_reader).registered);
+ cmm_barrier();
+ tmp = URCU_TLS(urcu_mb_reader).ctr;
+ urcu_assert((tmp & URCU_GP_CTR_NEST_MASK) != URCU_GP_CTR_NEST_MASK);
+ _urcu_mb_read_lock_update(tmp);
+}
+
+/*
+ * This is a helper function for _urcu_mb_read_unlock().
+ *
+ * The first cmm_smp_mb() call ensures that the critical section is
+ * seen to precede the store to rcu_reader.ctr.
+ * The second cmm_smp_mb() call ensures that we write to rcu_reader.ctr
+ * before reading the update-side futex.
+ */
+static inline void _urcu_mb_read_unlock_update_and_wakeup(unsigned long tmp)
+{
+ if (caa_likely((tmp & URCU_GP_CTR_NEST_MASK) == URCU_GP_COUNT)) {
+ cmm_smp_mb();
+ _CMM_STORE_SHARED(URCU_TLS(urcu_mb_reader).ctr, tmp - URCU_GP_COUNT);
+ cmm_smp_mb();
+ urcu_common_wake_up_gp(&urcu_mb_gp);
+ } else
+ _CMM_STORE_SHARED(URCU_TLS(urcu_mb_reader).ctr, tmp - URCU_GP_COUNT);
+}
+
+/*
+ * Exit an RCU read-side crtical section. Both this function and its
+ * helper are smaller than 10 lines of code, and are intended to be
+ * usable by non-LGPL code, as called out in LGPL.
+ */
+static inline void _urcu_mb_read_unlock(void)
+{
+ unsigned long tmp;
+
+ urcu_assert(URCU_TLS(urcu_mb_reader).registered);
+ tmp = URCU_TLS(urcu_mb_reader).ctr;
+ urcu_assert(tmp & URCU_GP_CTR_NEST_MASK);
+ _urcu_mb_read_unlock_update_and_wakeup(tmp);
+ cmm_barrier(); /* Ensure the compiler does not reorder us with mutex */
+}
+
+/*
+ * Returns whether within a RCU read-side critical section.
+ *
+ * This function is less than 10 lines long. The intent is that this
+ * function meets the 10-line criterion for LGPL, allowing this function
+ * to be invoked directly from non-LGPL code.
+ */
+static inline int _urcu_mb_read_ongoing(void)
+{
+ return URCU_TLS(urcu_mb_reader).ctr & URCU_GP_CTR_NEST_MASK;
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _URCU_MB_STATIC_H */
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