spinlock.h revision 331756
1227569Sphilip/*- 2227569Sphilip * Copyright (c) 2010 Isilon Systems, Inc. 3227569Sphilip * Copyright (c) 2010 iX Systems, Inc. 4227569Sphilip * Copyright (c) 2010 Panasas, Inc. 5227569Sphilip * Copyright (c) 2013-2017 Mellanox Technologies, Ltd. 6227569Sphilip * All rights reserved. 7227569Sphilip * 8227569Sphilip * Redistribution and use in source and binary forms, with or without 9227569Sphilip * modification, are permitted provided that the following conditions 10227569Sphilip * are met: 11227569Sphilip * 1. Redistributions of source code must retain the above copyright 12227569Sphilip * notice unmodified, this list of conditions, and the following 13227569Sphilip * disclaimer. 14227569Sphilip * 2. Redistributions in binary form must reproduce the above copyright 15227569Sphilip * notice, this list of conditions and the following disclaimer in the 16227569Sphilip * documentation and/or other materials provided with the distribution. 17227569Sphilip * 18227569Sphilip * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19227569Sphilip * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20227569Sphilip * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21227569Sphilip * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22227569Sphilip * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23227569Sphilip * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24227569Sphilip * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25227569Sphilip * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26228078Sphilip * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27228078Sphilip * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28228078Sphilip * 29227569Sphilip * $FreeBSD: stable/11/sys/compat/linuxkpi/common/include/linux/spinlock.h 331756 2018-03-30 02:04:46Z emaste $ 30227569Sphilip */ 31227569Sphilip#ifndef _LINUX_SPINLOCK_H_ 32227569Sphilip#define _LINUX_SPINLOCK_H_ 33227569Sphilip 34227569Sphilip#include <sys/param.h> 35227569Sphilip#include <sys/kernel.h> 36227569Sphilip#include <sys/lock.h> 37227569Sphilip#include <sys/mutex.h> 38227569Sphilip#include <sys/kdb.h> 39227569Sphilip 40227569Sphilip#include <linux/compiler.h> 41227569Sphilip#include <linux/rwlock.h> 42227569Sphilip#include <linux/bottom_half.h> 43227569Sphilip 44227569Sphiliptypedef struct { 45227569Sphilip struct mtx m; 46227569Sphilip} spinlock_t; 47227569Sphilip 48227569Sphilip/* 49227569Sphilip * By defining CONFIG_SPIN_SKIP LinuxKPI spinlocks and asserts will be 50227569Sphilip * skipped during panic(). By default it is disabled due to 51227569Sphilip * performance reasons. 52227569Sphilip */ 53227569Sphilip#ifdef CONFIG_SPIN_SKIP 54227569Sphilip#define SPIN_SKIP(void) unlikely(SCHEDULER_STOPPED() || kdb_active) 55227569Sphilip#else 56227569Sphilip#define SPIN_SKIP(void) 0 57227569Sphilip#endif 58227569Sphilip 59227569Sphilip#define spin_lock(_l) do { \ 60227569Sphilip if (SPIN_SKIP()) \ 61227569Sphilip break; \ 62227569Sphilip mtx_lock(&(_l)->m); \ 63227569Sphilip local_bh_disable(); \ 64227569Sphilip} while (0) 65227569Sphilip 66227569Sphilip#define spin_lock_bh(_l) do { \ 67227569Sphilip spin_lock(_l); \ 68227569Sphilip} while (0) 69227569Sphilip 70227569Sphilip#define spin_lock_irq(_l) do { \ 71227569Sphilip spin_lock(_l); \ 72227569Sphilip} while (0) 73227569Sphilip 74227569Sphilip#define spin_unlock(_l) do { \ 75227569Sphilip if (SPIN_SKIP()) \ 76227569Sphilip break; \ 77227569Sphilip local_bh_enable(); \ 78227569Sphilip mtx_unlock(&(_l)->m); \ 79227569Sphilip} while (0) 80227569Sphilip 81227569Sphilip#define spin_unlock_bh(_l) do { \ 82227569Sphilip spin_unlock(_l); \ 83227569Sphilip} while (0) 84227569Sphilip 85227569Sphilip#define spin_unlock_irq(_l) do { \ 86227569Sphilip spin_unlock(_l); \ 87227569Sphilip} while (0) 88227569Sphilip 89227569Sphilip#define spin_trylock(_l) ({ \ 90227569Sphilip int __ret; \ 91227569Sphilip if (SPIN_SKIP()) { \ 92278839Sarybchik __ret = 1; \ 93278839Sarybchik } else { \ 94227569Sphilip __ret = mtx_trylock(&(_l)->m); \ 95227569Sphilip if (likely(__ret != 0)) \ 96227569Sphilip local_bh_disable(); \ 97227569Sphilip } \ 98227569Sphilip __ret; \ 99227569Sphilip}) 100227569Sphilip 101227569Sphilip#define spin_trylock_irq(_l) \ 102227569Sphilip spin_trylock(_l) 103227569Sphilip 104227569Sphilip#define spin_lock_nested(_l, _n) do { \ 105227569Sphilip if (SPIN_SKIP()) \ 106278839Sarybchik break; \ 107278839Sarybchik mtx_lock_flags(&(_l)->m, MTX_DUPOK); \ 108227569Sphilip local_bh_disable(); \ 109227569Sphilip} while (0) 110227569Sphilip 111227569Sphilip#define spin_lock_irqsave(_l, flags) do { \ 112227569Sphilip (flags) = 0; \ 113227569Sphilip spin_lock(_l); \ 114227569Sphilip} while (0) 115227569Sphilip 116227569Sphilip#define spin_lock_irqsave_nested(_l, flags, _n) do { \ 117227569Sphilip (flags) = 0; \ 118227569Sphilip spin_lock_nested(_l, _n); \ 119227569Sphilip} while (0) 120227569Sphilip 121227569Sphilip#define spin_unlock_irqrestore(_l, flags) do { \ 122227569Sphilip spin_unlock(_l); \ 123227569Sphilip} while (0) 124227569Sphilip 125227569Sphilip#ifdef WITNESS_ALL 126227569Sphilip/* NOTE: the maximum WITNESS name is 64 chars */ 127227569Sphilip#define __spin_lock_name(name, file, line) \ 128227569Sphilip (((const char *){file ":" #line "-" name}) + \ 129227569Sphilip (sizeof(file) > 16 ? sizeof(file) - 16 : 0)) 130227569Sphilip#else 131227569Sphilip#define __spin_lock_name(name, file, line) name 132227569Sphilip#endif 133227569Sphilip#define _spin_lock_name(...) __spin_lock_name(__VA_ARGS__) 134227569Sphilip#define spin_lock_name(name) _spin_lock_name(name, __FILE__, __LINE__) 135227569Sphilip 136227569Sphilip#define spin_lock_init(lock) linux_spin_lock_init(lock, spin_lock_name("lnxspin")) 137227569Sphilip 138227569Sphilipstatic inline void 139227569Sphiliplinux_spin_lock_init(spinlock_t *lock, const char *name) 140227569Sphilip{ 141227569Sphilip 142227569Sphilip memset(lock, 0, sizeof(*lock)); 143227569Sphilip mtx_init(&lock->m, name, NULL, MTX_DEF | MTX_NOWITNESS); 144227569Sphilip} 145227569Sphilip 146227569Sphilipstatic inline void 147227569Sphilipspin_lock_destroy(spinlock_t *lock) 148227569Sphilip{ 149227569Sphilip 150227569Sphilip mtx_destroy(&lock->m); 151227569Sphilip} 152227569Sphilip 153227569Sphilip#define DEFINE_SPINLOCK(lock) \ 154227569Sphilip spinlock_t lock; \ 155227569Sphilip MTX_SYSINIT(lock, &(lock).m, spin_lock_name("lnxspin"), MTX_DEF) 156227569Sphilip 157227569Sphilip#define assert_spin_locked(_l) do { \ 158227569Sphilip if (SPIN_SKIP()) \ 159227569Sphilip break; \ 160227569Sphilip mtx_assert(&(_l)->m, MA_OWNED); \ 161227569Sphilip} while (0) 162227569Sphilip 163227569Sphilip#endif /* _LINUX_SPINLOCK_H_ */ 164227569Sphilip