X-Git-Url: http://git.lttng.org/?p=urcu.git;a=blobdiff_plain;f=include%2Furcu%2Fstatic%2Furcu-signal.h;fp=include%2Furcu%2Fstatic%2Furcu-signal.h;h=0000000000000000000000000000000000000000;hp=07768b340a768a30584bdf643ff14c61097a8203;hb=aad674a9a583e09e854145f18c5d8854269dce8c;hpb=3d003c571cd461aba1935e5d21e1e04da7183970 diff --git a/include/urcu/static/urcu-signal.h b/include/urcu/static/urcu-signal.h deleted file mode 100644 index 07768b3..0000000 --- a/include/urcu/static/urcu-signal.h +++ /dev/null @@ -1,140 +0,0 @@ -// SPDX-FileCopyrightText: 2009 Mathieu Desnoyers -// 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 -#include -#include -#include - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#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 */