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Diffstat (limited to 'sys/contrib/ck/include/ck_cohort.h')
| -rw-r--r-- | sys/contrib/ck/include/ck_cohort.h | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/contrib/ck/include/ck_cohort.h b/sys/contrib/ck/include/ck_cohort.h new file mode 100644 index 000000000000..c13cfa0d49cb --- /dev/null +++ b/sys/contrib/ck/include/ck_cohort.h @@ -0,0 +1,161 @@ +/* + * Copyright 2013-2015 Samy Al Bahra. + * Copyright 2013 Brendon Scheinman. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 CK_COHORT_H +#define CK_COHORT_H + +/* + * This is an implementation of lock cohorts as described in: + * Dice, D.; Marathe, V.; and Shavit, N. 2012. + * Lock Cohorting: A General Technique for Designing NUMA Locks + */ + +#include <ck_cc.h> +#include <ck_pr.h> +#include <ck_stddef.h> + +enum ck_cohort_state { + CK_COHORT_STATE_GLOBAL = 0, + CK_COHORT_STATE_LOCAL = 1 +}; + +#define CK_COHORT_DEFAULT_LOCAL_PASS_LIMIT 10 + +#define CK_COHORT_NAME(N) ck_cohort_##N +#define CK_COHORT_INSTANCE(N) struct CK_COHORT_NAME(N) +#define CK_COHORT_INIT(N, C, GL, LL, P) ck_cohort_##N##_init(C, GL, LL, P) +#define CK_COHORT_LOCK(N, C, GC, LC) ck_cohort_##N##_lock(C, GC, LC) +#define CK_COHORT_UNLOCK(N, C, GC, LC) ck_cohort_##N##_unlock(C, GC, LC) +#define CK_COHORT_TRYLOCK(N, C, GLC, LLC, LUC) ck_cohort_##N##_trylock(C, GLC, LLC, LUC) +#define CK_COHORT_LOCKED(N, C, GC, LC) ck_cohort_##N##_locked(C, GC, LC) + +#define CK_COHORT_PROTOTYPE(N, GL, GU, GI, LL, LU, LI) \ + CK_COHORT_INSTANCE(N) { \ + void *global_lock; \ + void *local_lock; \ + enum ck_cohort_state release_state; \ + unsigned int waiting_threads; \ + unsigned int acquire_count; \ + unsigned int local_pass_limit; \ + }; \ + \ + CK_CC_INLINE static void \ + ck_cohort_##N##_init(struct ck_cohort_##N *cohort, \ + void *global_lock, void *local_lock, unsigned int pass_limit) \ + { \ + cohort->global_lock = global_lock; \ + cohort->local_lock = local_lock; \ + cohort->release_state = CK_COHORT_STATE_GLOBAL; \ + cohort->waiting_threads = 0; \ + cohort->acquire_count = 0; \ + cohort->local_pass_limit = pass_limit; \ + ck_pr_barrier(); \ + return; \ + } \ + \ + CK_CC_INLINE static void \ + ck_cohort_##N##_lock(CK_COHORT_INSTANCE(N) *cohort, \ + void *global_context, void *local_context) \ + { \ + \ + ck_pr_inc_uint(&cohort->waiting_threads); \ + LL(cohort->local_lock, local_context); \ + ck_pr_dec_uint(&cohort->waiting_threads); \ + \ + if (cohort->release_state == CK_COHORT_STATE_GLOBAL) { \ + GL(cohort->global_lock, global_context); \ + } \ + \ + ++cohort->acquire_count; \ + return; \ + } \ + \ + CK_CC_INLINE static void \ + ck_cohort_##N##_unlock(CK_COHORT_INSTANCE(N) *cohort, \ + void *global_context, void *local_context) \ + { \ + \ + if (ck_pr_load_uint(&cohort->waiting_threads) > 0 \ + && cohort->acquire_count < cohort->local_pass_limit) { \ + cohort->release_state = CK_COHORT_STATE_LOCAL; \ + } else { \ + GU(cohort->global_lock, global_context); \ + cohort->release_state = CK_COHORT_STATE_GLOBAL; \ + cohort->acquire_count = 0; \ + } \ + \ + ck_pr_fence_release(); \ + LU(cohort->local_lock, local_context); \ + \ + return; \ + } \ + \ + CK_CC_INLINE static bool \ + ck_cohort_##N##_locked(CK_COHORT_INSTANCE(N) *cohort, \ + void *global_context, void *local_context) \ + { \ + return GI(cohort->local_lock, local_context) || \ + LI(cohort->global_lock, global_context); \ + } + +#define CK_COHORT_TRYLOCK_PROTOTYPE(N, GL, GU, GI, GTL, LL, LU, LI, LTL) \ + CK_COHORT_PROTOTYPE(N, GL, GU, GI, LL, LU, LI) \ + CK_CC_INLINE static bool \ + ck_cohort_##N##_trylock(CK_COHORT_INSTANCE(N) *cohort, \ + void *global_context, void *local_context, \ + void *local_unlock_context) \ + { \ + \ + bool trylock_result; \ + \ + ck_pr_inc_uint(&cohort->waiting_threads); \ + trylock_result = LTL(cohort->local_lock, local_context); \ + ck_pr_dec_uint(&cohort->waiting_threads); \ + if (trylock_result == false) { \ + return false; \ + } \ + \ + if (cohort->release_state == CK_COHORT_STATE_GLOBAL && \ + GTL(cohort->global_lock, global_context) == false) { \ + LU(cohort->local_lock, local_unlock_context); \ + return false; \ + } \ + \ + ++cohort->acquire_count; \ + return true; \ + } + +#define CK_COHORT_INITIALIZER { \ + .global_lock = NULL, \ + .local_lock = NULL, \ + .release_state = CK_COHORT_STATE_GLOBAL, \ + .waiting_threads = 0, \ + .acquire_count = 0, \ + .local_pass_limit = CK_COHORT_DEFAULT_LOCAL_PASS_LIMIT \ +} + +#endif /* CK_COHORT_H */ |