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Diffstat (limited to 'src/dpdk_lib18/librte_eal/common/include/generic/rte_spinlock.h')
| -rwxr-xr-x | src/dpdk_lib18/librte_eal/common/include/generic/rte_spinlock.h | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/src/dpdk_lib18/librte_eal/common/include/generic/rte_spinlock.h b/src/dpdk_lib18/librte_eal/common/include/generic/rte_spinlock.h new file mode 100755 index 00000000..dea885c3 --- /dev/null +++ b/src/dpdk_lib18/librte_eal/common/include/generic/rte_spinlock.h @@ -0,0 +1,226 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * 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. + * * Neither the name of Intel Corporation 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 COPYRIGHT HOLDERS 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 COPYRIGHT + * OWNER 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. + */ + +#ifndef _RTE_SPINLOCK_H_ +#define _RTE_SPINLOCK_H_ + +/** + * @file + * + * RTE Spinlocks + * + * This file defines an API for read-write locks, which are implemented + * in an architecture-specific way. This kind of lock simply waits in + * a loop repeatedly checking until the lock becomes available. + * + * All locks must be initialised before use, and only initialised once. + * + */ + +#include <rte_lcore.h> +#ifdef RTE_FORCE_INTRINSICS +#include <rte_common.h> +#endif + +/** + * The rte_spinlock_t type. + */ +typedef struct { + volatile int locked; /**< lock status 0 = unlocked, 1 = locked */ +} rte_spinlock_t; + +/** + * A static spinlock initializer. + */ +#define RTE_SPINLOCK_INITIALIZER { 0 } + +/** + * Initialize the spinlock to an unlocked state. + * + * @param sl + * A pointer to the spinlock. + */ +static inline void +rte_spinlock_init(rte_spinlock_t *sl) +{ + sl->locked = 0; +} + +/** + * Take the spinlock. + * + * @param sl + * A pointer to the spinlock. + */ +static inline void +rte_spinlock_lock(rte_spinlock_t *sl); + +#ifdef RTE_FORCE_INTRINSICS +static inline void +rte_spinlock_lock(rte_spinlock_t *sl) +{ + while (__sync_lock_test_and_set(&sl->locked, 1)) + while(sl->locked) + rte_pause(); +} +#endif + +/** + * Release the spinlock. + * + * @param sl + * A pointer to the spinlock. + */ +static inline void +rte_spinlock_unlock (rte_spinlock_t *sl); + +#ifdef RTE_FORCE_INTRINSICS +static inline void +rte_spinlock_unlock (rte_spinlock_t *sl) +{ + __sync_lock_release(&sl->locked); +} +#endif + +/** + * Try to take the lock. + * + * @param sl + * A pointer to the spinlock. + * @return + * 1 if the lock is successfully taken; 0 otherwise. + */ +static inline int +rte_spinlock_trylock (rte_spinlock_t *sl); + +#ifdef RTE_FORCE_INTRINSICS +static inline int +rte_spinlock_trylock (rte_spinlock_t *sl) +{ + return (__sync_lock_test_and_set(&sl->locked,1) == 0); +} +#endif + +/** + * Test if the lock is taken. + * + * @param sl + * A pointer to the spinlock. + * @return + * 1 if the lock is currently taken; 0 otherwise. + */ +static inline int rte_spinlock_is_locked (rte_spinlock_t *sl) +{ + return sl->locked; +} + +/** + * The rte_spinlock_recursive_t type. + */ +typedef struct { + rte_spinlock_t sl; /**< the actual spinlock */ + volatile int user; /**< core id using lock, -1 for unused */ + volatile int count; /**< count of time this lock has been called */ +} rte_spinlock_recursive_t; + +/** + * A static recursive spinlock initializer. + */ +#define RTE_SPINLOCK_RECURSIVE_INITIALIZER {RTE_SPINLOCK_INITIALIZER, -1, 0} + +/** + * Initialize the recursive spinlock to an unlocked state. + * + * @param slr + * A pointer to the recursive spinlock. + */ +static inline void rte_spinlock_recursive_init(rte_spinlock_recursive_t *slr) +{ + rte_spinlock_init(&slr->sl); + slr->user = -1; + slr->count = 0; +} + +/** + * Take the recursive spinlock. + * + * @param slr + * A pointer to the recursive spinlock. + */ +static inline void rte_spinlock_recursive_lock(rte_spinlock_recursive_t *slr) +{ + int id = rte_lcore_id(); + + if (slr->user != id) { + rte_spinlock_lock(&slr->sl); + slr->user = id; + } + slr->count++; +} +/** + * Release the recursive spinlock. + * + * @param slr + * A pointer to the recursive spinlock. + */ +static inline void rte_spinlock_recursive_unlock(rte_spinlock_recursive_t *slr) +{ + if (--(slr->count) == 0) { + slr->user = -1; + rte_spinlock_unlock(&slr->sl); + } + +} + +/** + * Try to take the recursive lock. + * + * @param slr + * A pointer to the recursive spinlock. + * @return + * 1 if the lock is successfully taken; 0 otherwise. + */ +static inline int rte_spinlock_recursive_trylock(rte_spinlock_recursive_t *slr) +{ + int id = rte_lcore_id(); + + if (slr->user != id) { + if (rte_spinlock_trylock(&slr->sl) == 0) + return 0; + slr->user = id; + } + slr->count++; + return 1; +} + +#endif /* _RTE_SPINLOCK_H_ */ |