urcu-qsbr.h: urcu/arch.h urcu/arch_uatomic.h
+urcu-pointer.o: urcu-pointer.c urcu-pointer.h urcu-pointer-static.h
+ $(CC) -fPIC ${CFLAGS} -c -o $@ $(SRC_DEP)
+
urcu.o: urcu.c urcu.h
$(CC) -fPIC ${CFLAGS} -c -o $@ $(SRC_DEP)
urcu-defer.o: urcu-defer.c urcu-defer.h
$(CC) -fPIC ${CFLAGS} -c -o $@ $(SRC_DEP)
-liburcu.so: urcu.o
+liburcu.so: urcu.o urcu-pointer.o
$(CC) ${LDFLAGS} -fPIC -shared -o $@ $<
-liburcu-qsbr.so: urcu-qsbr.o
+liburcu-qsbr.so: urcu-qsbr.o urcu-pointer.o
$(CC) ${LDFLAGS} -fPIC -shared -o $@ $<
-liburcu-mb.so: urcu-mb.o
+liburcu-mb.so: urcu-mb.o urcu-pointer.o
$(CC) ${LDFLAGS} -fPIC -shared -o $@ $<
liburcu-defer.so: urcu-defer.o
cp -f urcu.h urcu-static.h \
urcu-qsbr.h urcu-qsbr-static.h \
urcu-defer.h urcu-defer-static.h \
+ urcu-pointer.h urcu-pointer-static.h \
/usr/include/
clean:
CFLAGS+=-I${LIBDIR}
-URCU_SIGNAL=${LIBDIR}/urcu.o ${LIBDIR}/urcu.h
-URCU_SIGNAL_YIELD=${LIBDIR}/urcu-yield.o ${LIBDIR}/urcu.h
-URCU_MB=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu.h
-URCU_QSBR=${LIBDIR}/urcu-qsbr.o ${LIBDIR}/urcu-qsbr.h
-URCU_MB_DEFER=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu-defer.o ${LIBDIR}/urcu.h
+URCU_SIGNAL=${LIBDIR}/urcu.o ${LIBDIR}/urcu-pointer.o ${LIBDIR}/urcu.h
+URCU_SIGNAL_YIELD=${LIBDIR}/urcu-yield.o ${LIBDIR}/urcu-pointer.o ${LIBDIR}/urcu.h
+URCU_MB=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu-pointer.o ${LIBDIR}/urcu.h
+URCU_QSBR=${LIBDIR}/urcu-qsbr.o ${LIBDIR}/urcu-pointer.o ${LIBDIR}/urcu-qsbr.h
+URCU_MB_DEFER=${LIBDIR}/urcu-mb.o ${LIBDIR}/urcu-defer.o ${LIBDIR}/urcu-pointer.o ${LIBDIR}/urcu.h
all: test_urcu test_urcu_dynamic_link test_urcu_timing \
test_rwlock_timing test_rwlock test_perthreadlock_timing \
--- /dev/null
+#ifndef _URCU_POINTER_STATIC_H
+#define _URCU_POINTER_STATIC_H
+
+/*
+ * urcu-pointer-static.h
+ *
+ * Userspace RCU header. Operations on pointers.
+ *
+ * TO BE INCLUDED ONLY IN LGPL-COMPATIBLE CODE. See urcu-pointer.h for
+ * linking dynamically with the userspace rcu library.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * 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 <urcu/compiler.h>
+#include <urcu/arch.h>
+#include <urcu/system.h>
+#include <urcu/arch_uatomic.h>
+
+/**
+ * _rcu_dereference - reads (copy) a RCU-protected pointer to a local variable
+ * into a RCU read-side critical section. The pointer can later be safely
+ * dereferenced within the critical section.
+ *
+ * This ensures that the pointer copy is invariant thorough the whole critical
+ * section.
+ *
+ * Inserts memory barriers on architectures that require them (currently only
+ * Alpha) and documents which pointers are protected by RCU.
+ *
+ * The compiler memory barrier in LOAD_SHARED() ensures that value-speculative
+ * optimizations (e.g. VSS: Value Speculation Scheduling) does not perform the
+ * data read before the pointer read by speculating the value of the pointer.
+ * Correct ordering is ensured because the pointer is read as a volatile access.
+ * This acts as a global side-effect operation, which forbids reordering of
+ * dependent memory operations. Note that such concern about dependency-breaking
+ * optimizations will eventually be taken care of by the "memory_order_consume"
+ * addition to forthcoming C++ standard.
+ *
+ * Should match rcu_assign_pointer() or rcu_xchg_pointer().
+ */
+
+#define _rcu_dereference(p) ({ \
+ typeof(p) _________p1 = LOAD_SHARED(p); \
+ smp_read_barrier_depends(); \
+ (_________p1); \
+ })
+
+/**
+ * _rcu_cmpxchg_pointer - same as rcu_assign_pointer, but tests if the pointer
+ * is as expected by "old". If succeeds, returns the previous pointer to the
+ * data structure, which can be safely freed after waiting for a quiescent state
+ * using synchronize_rcu(). If fails (unexpected value), returns old (which
+ * should not be freed !).
+ */
+
+#define _rcu_cmpxchg_pointer(p, old, _new) \
+ ({ \
+ if (!__builtin_constant_p(_new) || \
+ ((_new) != NULL)) \
+ wmb(); \
+ uatomic_cmpxchg(p, old, _new); \
+ })
+
+/**
+ * _rcu_xchg_pointer - same as rcu_assign_pointer, but returns the previous
+ * pointer to the data structure, which can be safely freed after waiting for a
+ * quiescent state using synchronize_rcu().
+ */
+
+#define _rcu_xchg_pointer(p, v) \
+ ({ \
+ if (!__builtin_constant_p(v) || \
+ ((v) != NULL)) \
+ wmb(); \
+ uatomic_xchg(p, v); \
+ })
+
+
+#define _rcu_set_pointer(p, v) \
+ ({ \
+ if (!__builtin_constant_p(v) || \
+ ((v) != NULL)) \
+ wmb(); \
+ STORE_SHARED(*(p), v); \
+ })
+
+/*
+ * _rcu_publish_content - Exchanges the pointer and waits for quiescent state.
+ *
+ * The pointer returned can be freed.
+ */
+#define _rcu_publish_content(p, v) \
+ ({ \
+ void *oldptr; \
+ oldptr = _rcu_xchg_pointer(p, v); \
+ synchronize_rcu(); \
+ oldptr; \
+ })
+
+/**
+ * _rcu_assign_pointer - assign (publicize) a pointer to a new data structure
+ * meant to be read by RCU read-side critical sections. Returns the assigned
+ * value.
+ *
+ * Documents which pointers will be dereferenced by RCU read-side critical
+ * sections and adds the required memory barriers on architectures requiring
+ * them. It also makes sure the compiler does not reorder code initializing the
+ * data structure before its publication.
+ *
+ * Should match rcu_dereference_pointer().
+ */
+
+#define _rcu_assign_pointer(p, v) _rcu_set_pointer(&(p), v)
+
+#endif /* _URCU_POINTER_STATIC_H */
--- /dev/null
+
+/*
+ * urcu-pointer.c
+ *
+ * library wrappers to be used by non-LGPL compatible source code.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * 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 "urcu-pointer-static.h"
+/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
+#include "urcu-pointer.h"
+
+extern void synchronize_rcu(void);
+
+void *rcu_dereference(void *p)
+{
+ return _rcu_dereference(p);
+}
+
+void *rcu_set_pointer_sym(void **p, void *v)
+{
+ wmb();
+ return STORE_SHARED(*p, v);
+}
+
+void *rcu_xchg_pointer_sym(void **p, void *v)
+{
+ wmb();
+ return uatomic_xchg(p, v);
+}
+
+void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new)
+{
+ wmb();
+ return uatomic_cmpxchg(p, old, _new);
+}
+
+void *rcu_publish_content_sym(void **p, void *v)
+{
+ void *oldptr;
+
+ oldptr = _rcu_xchg_pointer(p, v);
+ synchronize_rcu();
+ return oldptr;
+}
--- /dev/null
+#ifndef _URCU_POINTER_H
+#define _URCU_POINTER_H
+
+/*
+ * urcu-pointer.h
+ *
+ * Userspace RCU header. Operations on pointers.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * 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 <urcu/compiler.h>
+#include <urcu/arch.h>
+#include <urcu/arch_uatomic.h>
+
+#ifdef _LGPL_SOURCE
+
+#include <urcu-pointer-static.h>
+
+/*
+ * rcu_dereference(ptr)
+ *
+ * Fetch a RCU-protected pointer. Typically used to copy the variable ptr to a
+ * local variable.
+ */
+#define rcu_dereference _rcu_dereference
+
+/*
+ * rcu_cmpxchg_pointer(type **ptr, type *new, type *old)
+ * type *rcu_xchg_pointer(type **ptr, type *new)
+ * type *rcu_set_pointer(type **ptr, type *new)
+ *
+ * RCU pointer updates.
+ * @ptr: address of the pointer to modify
+ * @new: new pointer value
+ * @old: old pointer value (expected)
+ *
+ * return: old pointer value
+ */
+#define rcu_cmpxchg_pointer _rcu_cmpxchg_pointer
+#define rcu_xchg_pointer _rcu_xchg_pointer
+#define rcu_set_pointer _rcu_set_pointer
+
+/*
+ * type *rcu_publish_content(type **ptr, type *new)
+ *
+ * Exchanges the pointer and waits for quiescent state. The pointer returned
+ * can be freed. You are encouraged to use either
+ * - rcu_cmpxchg_pointer
+ * - rcu_xchg_pointer
+ * - rcu_set_pointer
+ * with call_rcu(free, ptr) instead to deal with reclamation more efficiently.
+ */
+#define rcu_publish_content _rcu_publish_content
+
+#else /* !_LGPL_SOURCE */
+
+extern void *rcu_dereference(void *p);
+
+extern void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new);
+#define rcu_cmpxchg_pointer(p, old, _new) \
+ rcu_cmpxchg_pointer_sym((void **)(p), (old), (_new))
+
+extern void *rcu_xchg_pointer_sym(void **p, void *v);
+#define rcu_xchg_pointer(p, v) \
+ rcu_xchg_pointer_sym((void **)(p), (v))
+
+extern void *rcu_set_pointer_sym(void **p, void *v);
+#define rcu_set_pointer(p, v) \
+ rcu_set_pointer_sym((void **)(p), (v))
+
+extern void *rcu_publish_content_sym(void **p, void *v);
+#define rcu_publish_content(p, v) \
+ rcu_publish_content_sym((void **)(p), (v))
+
+extern void *rcu_assign_pointer_sym(void **p, void *v);
+
+#endif /* !_LGPL_SOURCE */
+
+/*
+ * rcu_assign_pointer(type *ptr, type *new)
+ *
+ * Same as rcu_set_pointer, but takes the pointer to assign to rather than its
+ * address as first parameter. Provided for compatibility with the Linux kernel
+ * RCU semantic.
+ */
+#define rcu_assign_pointer(p, v) rcu_set_pointer((&p), (v))
+
+#endif /* _URCU_POINTER_H */
#include <urcu/compiler.h>
#include <urcu/arch.h>
+#include <urcu/system.h>
#include <urcu/arch_uatomic.h>
#include <urcu/list.h>
-/*
- * Identify a shared load. A smp_rmc() or smp_mc() should come before the load.
- */
-#define _LOAD_SHARED(p) ACCESS_ONCE(p)
-
-/*
- * Load a data from shared memory, doing a cache flush if required.
- */
-#define LOAD_SHARED(p) \
- ({ \
- smp_rmc(); \
- _LOAD_SHARED(p); \
- })
-
-/*
- * Identify a shared store. A smp_wmc() or smp_mc() should follow the store.
- */
-#define _STORE_SHARED(x, v) ({ ACCESS_ONCE(x) = (v); })
-
-/*
- * Store v into x, where x is located in shared memory. Performs the required
- * cache flush after writing. Returns v.
- */
-#define STORE_SHARED(x, v) \
- ({ \
- _STORE_SHARED(x, v); \
- smp_wmc(); \
- (v); \
- })
-
-/**
- * _rcu_dereference - reads (copy) a RCU-protected pointer to a local variable
- * into a RCU read-side critical section. The pointer can later be safely
- * dereferenced within the critical section.
- *
- * This ensures that the pointer copy is invariant thorough the whole critical
- * section.
- *
- * Inserts memory barriers on architectures that require them (currently only
- * Alpha) and documents which pointers are protected by RCU.
- *
- * Should match rcu_assign_pointer() or rcu_xchg_pointer().
- */
-
-#define _rcu_dereference(p) ({ \
- typeof(p) _________p1 = LOAD_SHARED(p); \
- smp_read_barrier_depends(); \
- (_________p1); \
- })
-
#define futex(...) syscall(__NR_futex, __VA_ARGS__)
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
smp_mb();
}
-/**
- * _rcu_assign_pointer - assign (publicize) a pointer to a new data structure
- * meant to be read by RCU read-side critical sections. Returns the assigned
- * value.
- *
- * Documents which pointers will be dereferenced by RCU read-side critical
- * sections and adds the required memory barriers on architectures requiring
- * them. It also makes sure the compiler does not reorder code initializing the
- * data structure before its publication.
- *
- * Should match rcu_dereference_pointer().
- */
-
-#define _rcu_assign_pointer(p, v) \
- ({ \
- if (!__builtin_constant_p(v) || \
- ((v) != NULL)) \
- wmb(); \
- STORE_SHARED(p, v); \
- })
-
-/**
- * _rcu_cmpxchg_pointer - same as rcu_assign_pointer, but tests if the pointer
- * is as expected by "old". If succeeds, returns the previous pointer to the
- * data structure, which can be safely freed after waiting for a quiescent state
- * using synchronize_rcu(). If fails (unexpected value), returns old (which
- * should not be freed !).
- */
-
-#define _rcu_cmpxchg_pointer(p, old, _new) \
- ({ \
- if (!__builtin_constant_p(_new) || \
- ((_new) != NULL)) \
- wmb(); \
- uatomic_cmpxchg(p, old, _new); \
- })
-
-/**
- * _rcu_xchg_pointer - same as rcu_assign_pointer, but returns the previous
- * pointer to the data structure, which can be safely freed after waiting for a
- * quiescent state using synchronize_rcu().
- */
-
-#define _rcu_xchg_pointer(p, v) \
- ({ \
- if (!__builtin_constant_p(v) || \
- ((v) != NULL)) \
- wmb(); \
- uatomic_xchg(p, v); \
- })
-
-/*
- * Exchanges the pointer and waits for quiescent state.
- * The pointer returned can be freed.
- */
-#define _rcu_publish_content(p, v) \
- ({ \
- void *oldptr; \
- oldptr = _rcu_xchg_pointer(p, v); \
- synchronize_rcu(); \
- oldptr; \
- })
-
#endif /* _URCU_QSBR_STATIC_H */
_rcu_read_unlock();
}
-void *rcu_dereference(void *p)
-{
- return _rcu_dereference(p);
-}
-
-void *rcu_assign_pointer_sym(void **p, void *v)
-{
- wmb();
- return STORE_SHARED(*p, v);
-}
-
-void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new)
-{
- wmb();
- return uatomic_cmpxchg(p, old, _new);
-}
-
-void *rcu_xchg_pointer_sym(void **p, void *v)
-{
- wmb();
- return uatomic_xchg(p, v);
-}
-
-void *rcu_publish_content_sym(void **p, void *v)
-{
- void *oldptr;
-
- oldptr = _rcu_xchg_pointer(p, v);
- synchronize_rcu();
- return oldptr;
-}
-
void rcu_quiescent_state(void)
{
_rcu_quiescent_state();
#include <stdlib.h>
#include <pthread.h>
+/*
+ * See urcu-pointer.h and urcu-pointer-static.h for pointer publication headers.
+ */
+#include <urcu-pointer.h>
+
/*
* Important !
*
* Should only be used in LGPL-compatible code.
*/
-#define rcu_dereference _rcu_dereference
-#define rcu_read_lock _rcu_read_lock
-#define rcu_read_unlock _rcu_read_unlock
-
-#define rcu_quiescent_state _rcu_quiescent_state
-#define rcu_thread_offline _rcu_thread_offline
-#define rcu_thread_online _rcu_thread_online
+/*
+ * rcu_read_lock()
+ * rcu_read_unlock()
+ *
+ * Mark the beginning and end of a read-side critical section.
+ * DON'T FORGET TO USE RCU_REGISTER/UNREGISTER_THREAD() FOR EACH THREAD WITH
+ * READ-SIDE CRITICAL SECTION.
+ */
+#define rcu_read_lock() _rcu_read_lock()
+#define rcu_read_unlock() _rcu_read_unlock()
-#define rcu_assign_pointer _rcu_assign_pointer
-#define rcu_cmpxchg_pointer _rcu_cmpxchg_pointer
-#define rcu_xchg_pointer _rcu_xchg_pointer
-#define rcu_publish_content _rcu_publish_content
+#define rcu_quiescent_state() _rcu_quiescent_state()
+#define rcu_thread_offline() _rcu_thread_offline()
+#define rcu_thread_online() _rcu_thread_online()
#else /* !_LGPL_SOURCE */
#endif /* !URCU_DEBUG */
-extern void *rcu_dereference(void *p);
-
extern void rcu_quiescent_state(void);
extern void rcu_thread_offline(void);
extern void rcu_thread_online(void);
-extern void *rcu_assign_pointer_sym(void **p, void *v);
-
-#define rcu_assign_pointer(p, v) \
- rcu_assign_pointer_sym((void **)(&(p)), (v))
-
-extern void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new);
-#define rcu_cmpxchg_pointer(p, old, _new) \
- rcu_cmpxchg_pointer_sym((void **)(p), (old), (_new))
-
-extern void *rcu_xchg_pointer_sym(void **p, void *v);
-#define rcu_xchg_pointer(p, v) \
- rcu_xchg_pointer_sym((void **)(p), (v))
-
-extern void *rcu_publish_content_sym(void **p, void *v);
-#define rcu_publish_content(p, v) \
- rcu_publish_content_sym((void **)(p), (v))
-
#endif /* !_LGPL_SOURCE */
extern void synchronize_rcu(void);
#include <urcu/compiler.h>
#include <urcu/arch.h>
+#include <urcu/system.h>
#include <urcu/arch_uatomic.h>
#include <urcu/list.h>
-/*
- * Identify a shared load. A smp_rmc() or smp_mc() should come before the load.
- */
-#define _LOAD_SHARED(p) ACCESS_ONCE(p)
-
-/*
- * Load a data from shared memory, doing a cache flush if required.
- */
-#define LOAD_SHARED(p) \
- ({ \
- smp_rmc(); \
- _LOAD_SHARED(p); \
- })
-
-/*
- * Identify a shared store. A smp_wmc() or smp_mc() should follow the store.
- */
-#define _STORE_SHARED(x, v) ({ ACCESS_ONCE(x) = (v); })
-
-/*
- * Store v into x, where x is located in shared memory. Performs the required
- * cache flush after writing. Returns v.
- */
-#define STORE_SHARED(x, v) \
- ({ \
- _STORE_SHARED(x, v); \
- smp_wmc(); \
- (v); \
- })
-
-/**
- * _rcu_dereference - reads (copy) a RCU-protected pointer to a local variable
- * into a RCU read-side critical section. The pointer can later be safely
- * dereferenced within the critical section.
- *
- * This ensures that the pointer copy is invariant thorough the whole critical
- * section.
- *
- * Inserts memory barriers on architectures that require them (currently only
- * Alpha) and documents which pointers are protected by RCU.
- *
- * The compiler memory barrier in LOAD_SHARED() ensures that value-speculative
- * optimizations (e.g. VSS: Value Speculation Scheduling) does not perform the
- * data read before the pointer read by speculating the value of the pointer.
- * Correct ordering is ensured because the pointer is read as a volatile access.
- * This acts as a global side-effect operation, which forbids reordering of
- * dependent memory operations. Note that such concern about dependency-breaking
- * optimizations will eventually be taken care of by the "memory_order_consume"
- * addition to forthcoming C++ standard.
- *
- * Should match rcu_assign_pointer() or rcu_xchg_pointer().
- */
-
-#define _rcu_dereference(p) ({ \
- typeof(p) _________p1 = LOAD_SHARED(p); \
- smp_read_barrier_depends(); \
- (_________p1); \
- })
-
#define futex(...) syscall(__NR_futex, __VA_ARGS__)
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
}
}
-/**
- * _rcu_assign_pointer - assign (publicize) a pointer to a new data structure
- * meant to be read by RCU read-side critical sections. Returns the assigned
- * value.
- *
- * Documents which pointers will be dereferenced by RCU read-side critical
- * sections and adds the required memory barriers on architectures requiring
- * them. It also makes sure the compiler does not reorder code initializing the
- * data structure before its publication.
- *
- * Should match rcu_dereference_pointer().
- */
-
-#define _rcu_assign_pointer(p, v) \
- ({ \
- if (!__builtin_constant_p(v) || \
- ((v) != NULL)) \
- wmb(); \
- STORE_SHARED(p, v); \
- })
-
-/**
- * _rcu_cmpxchg_pointer - same as rcu_assign_pointer, but tests if the pointer
- * is as expected by "old". If succeeds, returns the previous pointer to the
- * data structure, which can be safely freed after waiting for a quiescent state
- * using synchronize_rcu(). If fails (unexpected value), returns old (which
- * should not be freed !).
- */
-
-#define _rcu_cmpxchg_pointer(p, old, _new) \
- ({ \
- if (!__builtin_constant_p(_new) || \
- ((_new) != NULL)) \
- wmb(); \
- uatomic_cmpxchg(p, old, _new); \
- })
-
-/**
- * _rcu_xchg_pointer - same as rcu_assign_pointer, but returns the previous
- * pointer to the data structure, which can be safely freed after waiting for a
- * quiescent state using synchronize_rcu().
- */
-
-#define _rcu_xchg_pointer(p, v) \
- ({ \
- if (!__builtin_constant_p(v) || \
- ((v) != NULL)) \
- wmb(); \
- uatomic_xchg(p, v); \
- })
-
-/*
- * Exchanges the pointer and waits for quiescent state.
- * The pointer returned can be freed.
- */
-#define _rcu_publish_content(p, v) \
- ({ \
- void *oldptr; \
- oldptr = _rcu_xchg_pointer(p, v); \
- synchronize_rcu(); \
- oldptr; \
- })
-
#endif /* _URCU_STATIC_H */
_rcu_read_unlock();
}
-void *rcu_dereference(void *p)
-{
- return _rcu_dereference(p);
-}
-
-void *rcu_assign_pointer_sym(void **p, void *v)
-{
- wmb();
- return STORE_SHARED(*p, v);
-}
-
-void *rcu_xchg_pointer_sym(void **p, void *v)
-{
- wmb();
- return uatomic_xchg(p, v);
-}
-
-void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new)
-{
- wmb();
- return uatomic_cmpxchg(p, old, _new);
-}
-
-void *rcu_publish_content_sym(void **p, void *v)
-{
- void *oldptr;
-
- oldptr = _rcu_xchg_pointer(p, v);
- synchronize_rcu();
- return oldptr;
-}
-
void rcu_register_thread(void)
{
urcu_reader.tid = pthread_self();
#include <stdlib.h>
#include <pthread.h>
+/*
+ * See urcu-pointer.h and urcu-pointer-static.h for pointer publication headers.
+ */
+#include <urcu-pointer.h>
+
/*
* Important !
*
* Should only be used in LGPL-compatible code.
*/
-#define rcu_dereference _rcu_dereference
-#define rcu_read_lock _rcu_read_lock
-#define rcu_read_unlock _rcu_read_unlock
-
-#define rcu_assign_pointer _rcu_assign_pointer
-#define rcu_cmpxchg_pointer _rcu_cmpxchg_pointer
-#define rcu_xchg_pointer _rcu_xchg_pointer
-#define rcu_publish_content _rcu_publish_content
+/*
+ * rcu_read_lock()
+ * rcu_read_unlock()
+ *
+ * Mark the beginning and end of a read-side critical section.
+ * DON'T FORGET TO USE RCU_REGISTER/UNREGISTER_THREAD() FOR EACH THREAD WITH
+ * READ-SIDE CRITICAL SECTION.
+ */
+#define rcu_read_lock() _rcu_read_lock()
+#define rcu_read_unlock() _rcu_read_unlock()
#else /* !_LGPL_SOURCE */
/*
* library wrappers to be used by non-LGPL compatible source code.
+ * See LGPL-only urcu-pointer-static.h for documentation.
*/
extern void rcu_read_lock(void);
extern void rcu_read_unlock(void);
-extern void *rcu_dereference(void *p);
-
-extern void *rcu_assign_pointer_sym(void **p, void *v);
-
-#define rcu_assign_pointer(p, v) \
- rcu_assign_pointer_sym((void **)(&(p)), (v))
-
-extern void *rcu_cmpxchg_pointer_sym(void **p, void *old, void *_new);
-#define rcu_cmpxchg_pointer(p, old, _new) \
- rcu_cmpxchg_pointer_sym((void **)(p), (old), (_new))
-
-extern void *rcu_xchg_pointer_sym(void **p, void *v);
-#define rcu_xchg_pointer(p, v) \
- rcu_xchg_pointer_sym((void **)(p), (v))
-
-extern void *rcu_publish_content_sym(void **p, void *v);
-#define rcu_publish_content(p, v) \
- rcu_publish_content_sym((void **)(p), (v))
-
#endif /* !_LGPL_SOURCE */
extern void synchronize_rcu(void);
--- /dev/null
+#ifndef _URCU_SYSTEM_H
+#define _URCU_SYSTEM_H
+
+/*
+ * system.h
+ *
+ * System definitions.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+
+#include <urcu/compiler.h>
+#include <urcu/arch.h>
+
+/*
+ * Identify a shared load. A smp_rmc() or smp_mc() should come before the load.
+ */
+#define _LOAD_SHARED(p) ACCESS_ONCE(p)
+
+/*
+ * Load a data from shared memory, doing a cache flush if required.
+ */
+#define LOAD_SHARED(p) \
+ ({ \
+ smp_rmc(); \
+ _LOAD_SHARED(p); \
+ })
+
+/*
+ * Identify a shared store. A smp_wmc() or smp_mc() should follow the store.
+ */
+#define _STORE_SHARED(x, v) ({ ACCESS_ONCE(x) = (v); })
+
+/*
+ * Store v into x, where x is located in shared memory. Performs the required
+ * cache flush after writing. Returns v.
+ */
+#define STORE_SHARED(x, v) \
+ ({ \
+ _STORE_SHARED(x, v); \
+ smp_wmc(); \
+ (v); \
+ })
+
+#endif /* _URCU_SYSTEM_H */
projects / urcu.git / commitdiff
