projects / OpenSPARC-T2-SAM / blame
| Commit | Line | Data |
|---|---|---|
| 920dae64 AT |
1 | /* |
| 2 | * ========== Copyright Header Begin ========================================== | |
| 3 | * | |
| 4 | * OpenSPARC T2 Processor File: barrier.c | |
| 5 | * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. | |
| 6 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES. | |
| 7 | * | |
| 8 | * The above named program is free software; you can redistribute it and/or | |
| 9 | * modify it under the terms of the GNU General Public | |
| 10 | * License version 2 as published by the Free Software Foundation. | |
| 11 | * | |
| 12 | * The above named program is distributed in the hope that it will be | |
| 13 | * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 15 | * General Public License for more details. | |
| 16 | * | |
| 17 | * You should have received a copy of the GNU General Public | |
| 18 | * License along with this work; if not, write to the Free Software | |
| 19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. | |
| 20 | * | |
| 21 | * ========== Copyright Header End ============================================ | |
| 22 | */ | |
| 23 | /* | |
| 24 | * Copyright 2006 Sun Microsystems, Inc. All rights reserved. | |
| 25 | * Use is subject to license terms. | |
| 26 | */ | |
| 27 | ||
| 28 | #pragma ident "@(#)barrier.c 1.2 06/09/12 SMI" | |
| 29 | ||
| 30 | #include <errno.h> | |
| 31 | #include <thread.h> | |
| 32 | ||
| 33 | #include "barrier.h" | |
| 34 | ||
| 35 | int | |
| 36 | barrier_init(barrier_t *bp, int count) | |
| 37 | { | |
| 38 | int n; | |
| 39 | int i; | |
| 40 | ||
| 41 | if (count < 1) | |
| 42 | return (EINVAL); | |
| 43 | ||
| 44 | bp->maxcnt = count; | |
| 45 | bp->sbp = &bp->sb[0]; | |
| 46 | ||
| 47 | for (i = 0; i < 2; ++i) { | |
| 48 | struct _sb *sbp = &(bp->sb[i]); | |
| 49 | sbp->runners = count; | |
| 50 | ||
| 51 | if (n = mutex_init(&sbp->wait_lk, NULL, NULL)) | |
| 52 | return (n); | |
| 53 | ||
| 54 | if (n = cond_init(&sbp->wait_cv, NULL, NULL)) | |
| 55 | return (n); | |
| 56 | } | |
| 57 | ||
| 58 | return (0); | |
| 59 | } | |
| 60 | ||
| 61 | void | |
| 62 | barrier_wait(barrier_t *bp) | |
| 63 | { | |
| 64 | struct _sb *sbp = bp->sbp; | |
| 65 | ||
| 66 | mutex_lock(&sbp->wait_lk); | |
| 67 | ||
| 68 | if (sbp->runners == 1) { | |
| 69 | /* last thread to reach barrier */ | |
| 70 | ||
| 71 | if (bp->maxcnt != 1) { | |
| 72 | /* reset runner count and switch sub-barriers */ | |
| 73 | sbp->runners = bp->maxcnt; | |
| 74 | bp->sbp = (bp->sbp == &bp->sb[0]) | |
| 75 | ? &bp->sb[1] : &bp->sb[0]; | |
| 76 | ||
| 77 | /* wake up the waiters */ | |
| 78 | cond_broadcast(&sbp->wait_cv); | |
| 79 | } | |
| 80 | } else { | |
| 81 | sbp->runners--; /* one less runner */ | |
| 82 | ||
| 83 | while (sbp->runners != bp->maxcnt) | |
| 84 | cond_wait(&sbp->wait_cv, &sbp->wait_lk); | |
| 85 | } | |
| 86 | ||
| 87 | mutex_unlock(&sbp->wait_lk); | |
| 88 | } | |
| 89 | ||
| 90 | int | |
| 91 | barrier_busy_init(barrier_busy_t *bbp, int count) | |
| 92 | { | |
| 93 | int i; | |
| 94 | ||
| 95 | if (count < 1) | |
| 96 | return (EINVAL); | |
| 97 | ||
| 98 | bbp->maxcnt = count; | |
| 99 | bbp->sbbp = &bbp->sbb[0]; | |
| 100 | ||
| 101 | for (i = 0; i < 2; ++i) { | |
| 102 | struct _sbb *sbbp = &(bbp->sbb[i]); | |
| 103 | sbbp->runners = count; | |
| 104 | sbbp->spin_cv = ~0; | |
| 105 | } | |
| 106 | ||
| 107 | return (0); | |
| 108 | } | |
| 109 | ||
| 110 | void | |
| 111 | barrier_busy_wait(barrier_busy_t *bbp) | |
| 112 | { | |
| 113 | extern uint32_t sim_atomic_add_32_nv(uint32_t *target, int32_t delta); | |
| 114 | struct _sbb *sbbp = bbp->sbbp; | |
| 115 | ||
| 116 | if (bbp->maxcnt == 1) | |
| 117 | return; | |
| 118 | ||
| 119 | if (sim_atomic_add_32_nv((uint32_t *)&sbbp->runners, -1) == 0) { | |
| 120 | /* last thread to reach barrier */ | |
| 121 | ||
| 122 | /* switch sub-barriers, reset runner count and "cv" */ | |
| 123 | bbp->sbbp = (bbp->sbbp == &bbp->sbb[0]) | |
| 124 | ? &bbp->sbb[1] : &bbp->sbb[0]; | |
| 125 | bbp->sbbp->runners = bbp->maxcnt; | |
| 126 | bbp->sbbp->spin_cv = ~0; | |
| 127 | ||
| 128 | /* release the busy-waiters */ | |
| 129 | sbbp->spin_cv = 0; | |
| 130 | } else { | |
| 131 | while (sbbp->spin_cv) | |
| 132 | ; | |
| 133 | } | |
| 134 | } |