+++ /dev/null
-// SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
-// SPDX-FileCopyrightText: 2009 Paul E. McKenney, IBM Corporation.
-//
-// SPDX-License-Identifier: LGPL-2.1-or-later
-
-#ifndef _URCU_SIGNAL_STATIC_H
-#define _URCU_SIGNAL_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.
- *
- * 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/debug.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/static/urcu-common.h>
-#include <urcu/static/urcu-signal-nr.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_signal_gp;
-
-extern DECLARE_URCU_TLS(struct urcu_reader, urcu_signal_reader);
-
-/*
- * Helper for _rcu_read_lock(). The format of urcu_signal_gp.ctr (as well as
- * the per-thread rcu_reader.ctr) has the lower-order bits containing a count of
- * _rcu_read_lock() nesting, and a single high-order URCU_BP_GP_CTR_PHASE bit
- * that contains either zero or one. The cmm_barrier() ensures that the accesses in
- * _rcu_read_lock() happen before the subsequent read-side critical section.
- */
-static inline void _urcu_signal_read_lock_update(unsigned long tmp)
-{
- if (caa_likely(!(tmp & URCU_GP_CTR_NEST_MASK))) {
- _CMM_STORE_SHARED(URCU_TLS(urcu_signal_reader).ctr, _CMM_LOAD_SHARED(urcu_signal_gp.ctr));
- cmm_smp_mb();
- } else
- _CMM_STORE_SHARED(URCU_TLS(urcu_signal_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 _rcu_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_signal_read_lock(void)
-{
- unsigned long tmp;
-
- urcu_assert_debug(URCU_TLS(urcu_signal_reader).registered);
- cmm_barrier();
- tmp = URCU_TLS(urcu_signal_reader).ctr;
- urcu_assert_debug((tmp & URCU_GP_CTR_NEST_MASK) != URCU_GP_CTR_NEST_MASK);
- _urcu_signal_read_lock_update(tmp);
-}
-
-/*
- * This is a helper function for _rcu_read_unlock().
- *
- * The first cmm_barrier() call ensures that the critical section is
- * seen to precede the store to rcu_reader.ctr.
- * The second cmm_barrier() call ensures that we write to rcu_reader.ctr
- * before reading the update-side futex.
- */
-static inline void _urcu_signal_read_unlock_update_and_wakeup(unsigned long tmp)
-{
- unsigned long *ctr = &URCU_TLS(urcu_signal_reader).ctr;
-
- if (caa_likely((tmp & URCU_GP_CTR_NEST_MASK) == URCU_GP_COUNT)) {
- uatomic_store(ctr, tmp - URCU_GP_COUNT, CMM_SEQ_CST);
- urcu_common_wake_up_gp(&urcu_signal_gp);
- } else {
- uatomic_store(ctr, tmp - URCU_GP_COUNT, CMM_RELAXED);
- }
-}
-
-/*
- * Exit an RCU read-side critical 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_signal_read_unlock(void)
-{
- unsigned long tmp;
-
- urcu_assert_debug(URCU_TLS(urcu_signal_reader).registered);
- tmp = URCU_TLS(urcu_signal_reader).ctr;
- urcu_assert_debug(tmp & URCU_GP_CTR_NEST_MASK);
- _urcu_signal_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_signal_read_ongoing(void)
-{
- return URCU_TLS(urcu_signal_reader).ctr & URCU_GP_CTR_NEST_MASK;
-}
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _URCU_SIGNAL_STATIC_H */
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