lock.h revision 102448
118334Speter/*- 290285Sobrien * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. 3169699Skan * 4169699Skan * Redistribution and use in source and binary forms, with or without 518334Speter * modification, are permitted provided that the following conditions 690285Sobrien * are met: 718334Speter * 1. Redistributions of source code must retain the above copyright 890285Sobrien * notice, this list of conditions and the following disclaimer. 990285Sobrien * 2. Redistributions in binary form must reproduce the above copyright 1090285Sobrien * notice, this list of conditions and the following disclaimer in the 1190285Sobrien * documentation and/or other materials provided with the distribution. 1218334Speter * 3. Berkeley Software Design Inc's name may not be used to endorse or 1390285Sobrien * promote products derived from this software without specific prior 1490285Sobrien * written permission. 1590285Sobrien * 1690285Sobrien * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND 1718334Speter * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1818334Speter * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1990285Sobrien * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE 20169699Skan * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21169699Skan * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2218334Speter * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2318334Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2418334Speter * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2518334Speter * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2618334Speter * SUCH DAMAGE. 2718334Speter * 2818334Speter * from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $ 2918334Speter * $FreeBSD: head/sys/sys/lock.h 102448 2002-08-26 18:31:26Z iedowse $ 3018334Speter */ 31169699Skan 3218334Speter#ifndef _SYS_LOCK_H_ 3318334Speter#define _SYS_LOCK_H_ 3418334Speter 3518334Speter/* 3618334Speter * XXX - compatability until lockmgr() goes away or all the #includes are 3718334Speter * updated. 3818334Speter */ 3918334Speter#include <sys/lockmgr.h> 4018334Speter 4118334Speter#include <sys/queue.h> 4218334Speter#include <sys/_lock.h> 4318334Speter 4418334Speter/* 4518334Speter * Lock classes. Each lock has a class which describes characteristics 4618334Speter * common to all types of locks of a given class. 4718334Speter * 4818334Speter * Spin locks in general must always protect against preemption, as it is 4918334Speter * an error to perform any type of context switch while holding a spin lock. 5018334Speter * Also, for an individual lock to be recursable, its class must allow 5118334Speter * recursion and the lock itself must explicitly allow recursion. 5218334Speter */ 5318334Speter 5418334Speterstruct lock_class { 5518334Speter const char *lc_name; 5618334Speter u_int lc_flags; 5718334Speter}; 5818334Speter 5918334Speter#define LC_SLEEPLOCK 0x00000001 /* Sleep lock. */ 6018334Speter#define LC_SPINLOCK 0x00000002 /* Spin lock. */ 6118334Speter#define LC_SLEEPABLE 0x00000004 /* Sleeping allowed with this lock. */ 6218334Speter#define LC_RECURSABLE 0x00000008 /* Locks of this type may recurse. */ 6318334Speter#define LC_UPGRADABLE 0x00000010 /* Upgrades and downgrades permitted. */ 6418334Speter 6518334Speter#define LO_CLASSFLAGS 0x0000ffff /* Class specific flags. */ 6618334Speter#define LO_INITIALIZED 0x00010000 /* Lock has been initialized. */ 6718334Speter#define LO_WITNESS 0x00020000 /* Should witness monitor this lock. */ 6818334Speter#define LO_QUIET 0x00040000 /* Don't log locking operations. */ 6918334Speter#define LO_RECURSABLE 0x00080000 /* Lock may recurse. */ 7018334Speter#define LO_SLEEPABLE 0x00100000 /* Lock may be held while sleeping. */ 7118334Speter#define LO_UPGRADABLE 0x00200000 /* Lock may be upgraded/downgraded. */ 7218334Speter#define LO_DUPOK 0x00400000 /* Don't check for duplicate acquires */ 7318334Speter 7418334Speter#define LI_RECURSEMASK 0x0000ffff /* Recursion depth of lock instance. */ 7518334Speter#define LI_SLEPT 0x00010000 /* Lock instance has been slept with. */ 7618334Speter#define LI_EXCLUSIVE 0x00020000 /* Exclusive lock instance. */ 7718334Speter 7818334Speter/* 7918334Speter * Option flags passed to lock operations that witness also needs to know 8018334Speter * about or that are generic across all locks. 8118334Speter */ 8218334Speter#define LOP_QUIET 0x00000002 /* Don't log locking operations. */ 8318334Speter#define LOP_TRYLOCK 0x00000004 /* Don't check lock order. */ 8418334Speter#define LOP_EXCLUSIVE 0x00000008 /* Exclusive lock. */ 8518334Speter 8618334Speter/* Flags passed to witness_assert. */ 8718334Speter#define LA_UNLOCKED 0x00000000 /* Lock is unlocked. */ 8818334Speter#define LA_LOCKED 0x00000001 /* Lock is at least share locked. */ 8918334Speter#define LA_SLOCKED 0x00000002 /* Lock is exactly share locked. */ 9018334Speter#define LA_XLOCKED 0x00000004 /* Lock is exclusively locked. */ 9118334Speter#define LA_RECURSED 0x00000008 /* Lock is recursed. */ 9250605Sobrien#define LA_NOTRECURSED 0x00000010 /* Lock is not recursed. */ 93132727Skan 94132727Skan#ifdef _KERNEL 9518334Speter/* 9690285Sobrien * Lock instances. A lock instance is the data associated with a lock while 9718334Speter * it is held by witness. For example, a lock instance will hold the 9890285Sobrien * recursion count of a lock. Lock instances are held in lists. Spin locks 9990285Sobrien * are held in a per-cpu list while sleep locks are held in per-process list. 10018334Speter */ 10118334Speterstruct lock_instance { 10218334Speter struct lock_object *li_lock; 103169699Skan const char *li_file; /* File and line of last acquire. */ 10418334Speter int li_line; 10518334Speter u_int li_flags; /* Recursion count and LI_* flags. */ 10618334Speter}; 10718334Speter 10890285Sobrien/* 10950605Sobrien * A simple list type used to build the list of locks held by a process 110132727Skan * or CPU. We can't simply embed the list in struct lock_object since a 111169699Skan * lock may be held by more than one process if it is a shared lock. Locks 11218334Speter * are added to the head of the list, so we fill up each list entry from 113169699Skan * "the back" logically. To ease some of the arithmetic, we actually fill 114169699Skan * in each list entry the normal way (childer[0] then children[1], etc.) but 115169699Skan * when we traverse the list we read children[count-1] as the first entry 116169699Skan * down to children[0] as the final entry. 117169699Skan */ 11850605Sobrien#define LOCK_NCHILDREN 3 119169699Skan 120169699Skanstruct lock_list_entry { 121169699Skan struct lock_list_entry *ll_next; 122169699Skan struct lock_instance ll_children[LOCK_NCHILDREN]; 123169699Skan u_int ll_count; 124169699Skan}; 12518334Speter 12690285Sobrien/* 12790285Sobrien * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled, 12818334Speter * then turn on LOCK_DEBUG. When this option is on, extra debugging 12990285Sobrien * facilities such as tracking the file and line number of lock operations 13018334Speter * are enabled. Also, mutex locking operations are not inlined to avoid 13118334Speter * bloat from all the extra debugging code. We also have to turn on all the 13218334Speter * calling conventions for this debugging code in modules so that modules can 13318334Speter * work with both debug and non-debug kernels. 13418334Speter */ 13518334Speter#if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || defined(INVARIANT_SUPPORT) || defined(KTR) 13618334Speter#define LOCK_DEBUG 1 13718334Speter#else 13818334Speter#define LOCK_DEBUG 0 13918334Speter#endif 14018334Speter 14118334Speter/* 14218334Speter * In the LOCK_DEBUG case, use the filename and line numbers for debugging 14318334Speter * operations. Otherwise, use default values to avoid the unneeded bloat. 14418334Speter */ 14518334Speter#if LOCK_DEBUG > 0 14618334Speter#define LOCK_FILE __FILE__ 14718334Speter#define LOCK_LINE __LINE__ 14818334Speter#else 14918334Speter#define LOCK_FILE NULL 15018334Speter#define LOCK_LINE 0 15118334Speter#endif 15218334Speter 15318334Speter/* 15418334Speter * Macros for KTR_LOCK tracing. 15518334Speter * 15618334Speter * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) 15718334Speter * lo - struct lock_object * for this lock 15818334Speter * flags - flags passed to the lock operation 15918334Speter * recurse - this locks recursion level (or 0 if class is not recursable) 16018334Speter * result - result of a try lock operation 16118334Speter * file - file name 16218334Speter * line - line number 16318334Speter */ 16418334Speter#define LOCK_LOG_TEST(lo, flags) \ 16518334Speter (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) 16650605Sobrien 16750605Sobrien#define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ 16850605Sobrien if (LOCK_LOG_TEST((lo), (flags))) \ 16950605Sobrien CTR5(KTR_LOCK, opname " (%s) %s r = %d at %s:%d", \ 17018334Speter (lo)->lo_class->lc_name, (lo)->lo_name, \ 17118334Speter (u_int)(recurse), (file), (line)); \ 17218334Speter} while (0) 17318334Speter 17418334Speter#define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ 17518334Speter if (LOCK_LOG_TEST((lo), (flags))) \ 17690285Sobrien CTR5(KTR_LOCK, "TRY_" opname " (%s) %s result=%d at %s:%d",\ 17718334Speter (lo)->lo_class->lc_name, (lo)->lo_name, \ 17890285Sobrien (u_int)(result), (file), (line)); \ 17918334Speter} while (0) 18018334Speter 18118334Speter#define LOCK_LOG_INIT(lo, flags) do { \ 18218334Speter if (LOCK_LOG_TEST((lo), (flags))) \ 18318334Speter CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ 18418334Speter (lo)->lo_class->lc_name, (lo)->lo_name); \ 185132727Skan} while (0) 18618334Speter 18718334Speter#define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) 18818334Speter 18918334Speter/* 19018334Speter * Helpful macros for quickly coming up with assertions with informative 19118334Speter * panic messages. 19218334Speter */ 19318334Speter#define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) 19418334Speter#define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) 19518334Speter#define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) 19618334Speter#define MPASS4(ex, what, file, line) \ 19718334Speter KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) 19818334Speter 19918334Speterextern struct lock_class lock_class_mtx_sleep; 20018334Speterextern struct lock_class lock_class_mtx_spin; 20150605Sobrienextern struct lock_class lock_class_sx; 20218334Speter 20318334Spetervoid witness_init(struct lock_object *); 20418334Spetervoid witness_destroy(struct lock_object *); 20518334Spetervoid witness_lock(struct lock_object *, int, const char *, int); 20618334Spetervoid witness_upgrade(struct lock_object *, int, const char *, int); 20718334Spetervoid witness_downgrade(struct lock_object *, int, const char *, int); 20818334Spetervoid witness_unlock(struct lock_object *, int, const char *, int); 20918334Spetervoid witness_save(struct lock_object *, const char **, int *); 21018334Spetervoid witness_restore(struct lock_object *, const char *, int); 21118334Speterint witness_list_locks(struct lock_list_entry **); 21218334Speterint witness_list(struct thread *); 21318334Speterint witness_sleep(int, struct lock_object *, const char *, int); 21418334Spetervoid witness_assert(struct lock_object *, int, const char *, int); 215169699Skanint witness_line(struct lock_object *); 216169699Skanconst char *witness_file(struct lock_object *); 21718334Speter 21818334Speter#ifdef WITNESS 21918334Speter#define WITNESS_INIT(lock) \ 22018334Speter witness_init((lock)) 22118334Speter 22218334Speter#define WITNESS_DESTROY(lock) \ 22318334Speter witness_destroy(lock) 22418334Speter 22518334Speter#define WITNESS_LOCK(lock, flags, file, line) \ 22618334Speter witness_lock((lock), (flags), (file), (line)) 22718334Speter 22818334Speter#define WITNESS_UPGRADE(lock, flags, file, line) \ 22918334Speter witness_upgrade((lock), (flags), (file), (line)) 23018334Speter 23118334Speter#define WITNESS_DOWNGRADE(lock, flags, file, line) \ 23218334Speter witness_downgrade((lock), (flags), (file), (line)) 23318334Speter 23418334Speter#define WITNESS_UNLOCK(lock, flags, file, line) \ 23518334Speter witness_unlock((lock), (flags), (file), (line)) 23618334Speter 23718334Speter#define WITNESS_SLEEP(check, lock) \ 23850605Sobrien witness_sleep((check), (lock), __FILE__, __LINE__) 23950605Sobrien 24050605Sobrien#define WITNESS_SAVE_DECL(n) \ 24150605Sobrien const char * __CONCAT(n, __wf); \ 24250605Sobrien int __CONCAT(n, __wl) 24350605Sobrien 24450605Sobrien#define WITNESS_SAVE(lock, n) \ 24550605Sobrien witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) 24650605Sobrien 247132727Skan#define WITNESS_RESTORE(lock, n) \ 248132727Skan witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) 249169699Skan 250169699Skan#define WITNESS_FILE(lock) \ 251169699Skan witness_file(lock) 252132727Skan 253132727Skan#define WITNESS_LINE(lock) \ 254132727Skan witness_line(lock) 255132727Skan 256132727Skan#else /* WITNESS */ 257132727Skan#define WITNESS_INIT(lock) ((lock)->lo_flags |= LO_INITIALIZED) 258132727Skan#define WITNESS_DESTROY(lock) ((lock)->lo_flags &= ~LO_INITIALIZED) 259132727Skan#define WITNESS_LOCK(lock, flags, file, line) 260132727Skan#define WITNESS_UPGRADE(lock, flags, file, line) 261132727Skan#define WITNESS_DOWNGRADE(lock, flags, file, line) 262132727Skan#define WITNESS_UNLOCK(lock, flags, file, line) 263132727Skan#define WITNESS_SLEEP(check, lock) 264132727Skan#define WITNESS_SAVE_DECL(n) 265132727Skan#define WITNESS_SAVE(lock, n) 266132727Skan#define WITNESS_RESTORE(lock, n) 267132727Skan#define WITNESS_FILE(lock) ("?") 268132727Skan#define WITNESS_LINE(lock) (0) 269132727Skan#endif /* WITNESS */ 270132727Skan 271132727Skan#endif /* _KERNEL */ 272132727Skan#endif /* _SYS_LOCK_H_ */ 273169699Skan