1*4f8ce3b3Sriastradh/* $NetBSD: membar_ops.S,v 1.8 2022/04/09 23:32:52 riastradh Exp $ */ 2ebe806aaSad 3ebe806aaSad/*- 4ebe806aaSad * Copyright (c) 2007 The NetBSD Foundation, Inc. 5ebe806aaSad * All rights reserved. 6ebe806aaSad * 7ebe806aaSad * This code is derived from software contributed to The NetBSD Foundation 8ebe806aaSad * by Jason R. Thorpe, and by Andrew Doran. 9ebe806aaSad * 10ebe806aaSad * Redistribution and use in source and binary forms, with or without 11ebe806aaSad * modification, are permitted provided that the following conditions 12ebe806aaSad * are met: 13ebe806aaSad * 1. Redistributions of source code must retain the above copyright 14ebe806aaSad * notice, this list of conditions and the following disclaimer. 15ebe806aaSad * 2. Redistributions in binary form must reproduce the above copyright 16ebe806aaSad * notice, this list of conditions and the following disclaimer in the 17ebe806aaSad * documentation and/or other materials provided with the distribution. 18ebe806aaSad * 19ebe806aaSad * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20ebe806aaSad * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21ebe806aaSad * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22ebe806aaSad * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23ebe806aaSad * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24ebe806aaSad * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25ebe806aaSad * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26ebe806aaSad * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27ebe806aaSad * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28ebe806aaSad * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29ebe806aaSad * POSSIBILITY OF SUCH DAMAGE. 30ebe806aaSad */ 31ebe806aaSad 32ebe806aaSad#include "atomic_op_asm.h" 33ebe806aaSad 34da06f841Sriastradh#ifdef _KERNEL_OPT 35da06f841Sriastradh#include "opt_multiprocessor.h" 36da06f841Sriastradh#endif 37da06f841Sriastradh 38ebe806aaSad .text 39ebe806aaSad 40da06f841Sriastradh/* 41da06f841Sriastradh * These assume Total Store Order (TSO), which may reorder 42ca73d729Sriastradh * store-before-load but nothing else. Hence, only membar_sync (and 43ca73d729Sriastradh * its deprecated alias membar_enter) must issue anything -- 44ca73d729Sriastradh * specifically, an LDSTUB, which (along with SWAP) is the only 45ca73d729Sriastradh * instruction that implies a sequential consistency barrier. 46da06f841Sriastradh * 47da06f841Sriastradh * If we ran with Partial Store Order (PSO), we would also need to 48*4f8ce3b3Sriastradh * issue STBAR for membar_release (load/store-before-store) and 49da06f841Sriastradh * membar_producer (store-before-store). 50da06f841Sriastradh */ 51ebe806aaSad 52*4f8ce3b3SriastradhENTRY(_membar_acquire) 53ebe806aaSad retl 54da06f841Sriastradh nop 55*4f8ce3b3SriastradhEND(_membar_acquire) 56*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_acquire,_membar_acquire) 57*4f8ce3b3Sriastradh 58*4f8ce3b3SriastradhENTRY(_membar_release) 59*4f8ce3b3Sriastradh retl 60*4f8ce3b3Sriastradh nop 61*4f8ce3b3SriastradhEND(_membar_release) 62*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_release,_membar_release) 63ebe806aaSad 64da06f841SriastradhENTRY(_membar_sync) 65da06f841Sriastradh retl 66da06f841Sriastradh#if !defined(_KERNEL) || defined(MULTIPROCESSOR) 67da06f841Sriastradh ldstub [%sp - 4], %g0 68da06f841Sriastradh#else 69da06f841Sriastradh nop 70da06f841Sriastradh#endif 71da06f841SriastradhEND(_membar_sync) 72*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_sync,_membar_sync) 73da06f841Sriastradh 74*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_producer,_membar_release) 75*4f8ce3b3SriastradhSTRONG_ALIAS(_membar_producer,_membar_release) 76*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_consumer,_membar_acquire) 77*4f8ce3b3SriastradhSTRONG_ALIAS(_membar_consumer,_membar_acquire) 78ca73d729SriastradhATOMIC_OP_ALIAS(membar_enter,_membar_sync) 79ca73d729SriastradhSTRONG_ALIAS(_membar_enter,_membar_sync) 80*4f8ce3b3SriastradhATOMIC_OP_ALIAS(membar_exit,_membar_release) 81*4f8ce3b3SriastradhSTRONG_ALIAS(_membar_exit,_membar_release) 82