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Diffstat (limited to 'rtemsbsd/include/machine/_kernel_lock.h')
-rw-r--r-- | rtemsbsd/include/machine/_kernel_lock.h | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/rtemsbsd/include/machine/_kernel_lock.h b/rtemsbsd/include/machine/_kernel_lock.h index e69de29b..772e5dd2 100644 --- a/rtemsbsd/include/machine/_kernel_lock.h +++ b/rtemsbsd/include/machine/_kernel_lock.h @@ -0,0 +1,319 @@ +/*- + * Copyright (c) 1997 Berkeley Software Design, Inc. 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. + * 3. Berkeley Software Design Inc's name may not be used to endorse or + * promote products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC 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. + * + * from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $ + * $FreeBSD$ + */ + +#ifndef _MACHINE__KERNEL_LOCK_H_ +#define _MACHINE__KERNEL_LOCK_H_ + +#include <sys/queue.h> +#include <sys/_lock.h> + +struct lock_list_entry; +struct thread; + +/* + * Lock classes. Each lock has a class which describes characteristics + * common to all types of locks of a given class. + * + * Spin locks in general must always protect against preemption, as it is + * an error to perform any type of context switch while holding a spin lock. + * Also, for an individual lock to be recursable, its class must allow + * recursion and the lock itself must explicitly allow recursion. + * + * The 'lc_ddb_show' function pointer is used to dump class-specific + * data for the 'show lock' DDB command. The 'lc_lock' and + * 'lc_unlock' function pointers are used in sleep(9) and cv_wait(9) + * to lock and unlock locks while blocking on a sleep queue. The + * return value of 'lc_unlock' will be passed to 'lc_lock' on resume + * to allow communication of state between the two routines. + */ + +struct lock_class { + const char *lc_name; + unsigned int lc_flags; + void (*lc_assert)(struct lock_object *lock, int what); + void (*lc_ddb_show)(struct lock_object *lock); + void (*lc_lock)(struct lock_object *lock, int how); + int (*lc_owner)(struct lock_object *lock, struct thread **owner); + int (*lc_unlock)(struct lock_object *lock); +}; + +#define LC_SLEEPLOCK 0x00000001 /* Sleep lock. */ +#define LC_SPINLOCK 0x00000002 /* Spin lock. */ +#define LC_SLEEPABLE 0x00000004 /* Sleeping allowed with this lock. */ +#define LC_RECURSABLE 0x00000008 /* Locks of this type may recurse. */ +#define LC_UPGRADABLE 0x00000010 /* Upgrades and downgrades permitted. */ + +#define LO_CLASSFLAGS 0x0000ffff /* Class specific flags. */ +#define LO_INITIALIZED 0x00010000 /* Lock has been initialized. */ +#define LO_WITNESS 0x00020000 /* Should witness monitor this lock. */ +#define LO_QUIET 0x00040000 /* Don't log locking operations. */ +#define LO_RECURSABLE 0x00080000 /* Lock may recurse. */ +#define LO_SLEEPABLE 0x00100000 /* Lock may be held while sleeping. */ +#define LO_UPGRADABLE 0x00200000 /* Lock may be upgraded/downgraded. */ +#define LO_DUPOK 0x00400000 /* Don't check for duplicate acquires */ +#define LO_CLASSMASK 0x0f000000 /* Class index bitmask. */ +#define LO_NOPROFILE 0x10000000 /* Don't profile this lock */ + +/* + * Lock classes are statically assigned an index into the gobal lock_classes + * array. Debugging code looks up the lock class for a given lock object + * by indexing the array. + */ +#define LO_CLASSSHIFT 24 +#define LO_CLASSINDEX(lock) ((((lock)->lo_flags) & LO_CLASSMASK) >> LO_CLASSSHIFT) +#define LOCK_CLASS(lock) (lock_classes[LO_CLASSINDEX((lock))]) +#define LOCK_CLASS_MAX (LO_CLASSMASK >> LO_CLASSSHIFT) + +/* + * Option flags passed to lock operations that witness also needs to know + * about or that are generic across all locks. + */ +#define LOP_NEWORDER 0x00000001 /* Define a new lock order. */ +#define LOP_QUIET 0x00000002 /* Don't log locking operations. */ +#define LOP_TRYLOCK 0x00000004 /* Don't check lock order. */ +#define LOP_EXCLUSIVE 0x00000008 /* Exclusive lock. */ +#define LOP_DUPOK 0x00000010 /* Don't check for duplicate acquires */ + +/* Flags passed to witness_assert. */ +#define LA_MASKASSERT 0x000000ff /* Mask for witness defined asserts. */ +#define LA_UNLOCKED 0x00000000 /* Lock is unlocked. */ +#define LA_LOCKED 0x00000001 /* Lock is at least share locked. */ +#define LA_SLOCKED 0x00000002 /* Lock is exactly share locked. */ +#define LA_XLOCKED 0x00000004 /* Lock is exclusively locked. */ +#define LA_RECURSED 0x00000008 /* Lock is recursed. */ +#define LA_NOTRECURSED 0x00000010 /* Lock is not recursed. */ + +#ifdef _KERNEL +/* + * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled, + * then turn on LOCK_DEBUG. When this option is on, extra debugging + * facilities such as tracking the file and line number of lock operations + * are enabled. Also, mutex locking operations are not inlined to avoid + * bloat from all the extra debugging code. We also have to turn on all the + * calling conventions for this debugging code in modules so that modules can + * work with both debug and non-debug kernels. + */ +#if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || defined(INVARIANT_SUPPORT) || defined(KTR) || defined(LOCK_PROFILING) +#define LOCK_DEBUG 1 +#else +#define LOCK_DEBUG 0 +#endif + +/* + * In the LOCK_DEBUG case, use the filename and line numbers for debugging + * operations. Otherwise, use default values to avoid the unneeded bloat. + */ +#if LOCK_DEBUG > 0 +#define LOCK_FILE __FILE__ +#define LOCK_LINE __LINE__ +#else +#define LOCK_FILE NULL +#define LOCK_LINE 0 +#endif + +/* + * Macros for KTR_LOCK tracing. + * + * opname - name of this operation (LOCK/UNLOCK/SLOCK, etc.) + * lo - struct lock_object * for this lock + * flags - flags passed to the lock operation + * recurse - this locks recursion level (or 0 if class is not recursable) + * result - result of a try lock operation + * file - file name + * line - line number + */ +#define LOCK_LOG_TEST(lo, flags) \ + (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0) + +#define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do { \ + if (LOCK_LOG_TEST((lo), (flags))) \ + CTR6(KTR_LOCK, opname " (%s) %s %p r = %d at %s:%d", \ + LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ + (lo), (u_int)(recurse), (file), (line)); \ +} while (0) + +#define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do { \ + if (LOCK_LOG_TEST((lo), (flags))) \ + CTR6(KTR_LOCK, "TRY_" opname " (%s) %s %p result=%d at %s:%d",\ + LOCK_CLASS(lo)->lc_name, (lo)->lo_name, \ + (lo), (u_int)(result), (file), (line)); \ +} while (0) + +#define LOCK_LOG_INIT(lo, flags) do { \ + if (LOCK_LOG_TEST((lo), (flags))) \ + CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo), \ + LOCK_CLASS(lo)->lc_name, (lo)->lo_name); \ +} while (0) + +#define LOCK_LOG_DESTROY(lo, flags) LOCK_LOG_INIT(lo, flags) + +#define lock_initialized(lo) ((lo)->lo_flags & LO_INITIALIZED) + +/* + * Helpful macros for quickly coming up with assertions with informative + * panic messages. + */ +#define MPASS(ex) MPASS4(ex, #ex, __FILE__, __LINE__) +#define MPASS2(ex, what) MPASS4(ex, what, __FILE__, __LINE__) +#define MPASS3(ex, file, line) MPASS4(ex, #ex, file, line) +#define MPASS4(ex, what, file, line) \ + KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line)) + +extern struct lock_class lock_class_mtx_sleep; +extern struct lock_class lock_class_mtx_spin; +extern struct lock_class lock_class_sx; +extern struct lock_class lock_class_rw; +extern struct lock_class lock_class_rm; +extern struct lock_class lock_class_lockmgr; + +extern struct lock_class *lock_classes[]; + +void lock_init(struct lock_object *, struct lock_class *, + const char *, const char *, int); +void lock_destroy(struct lock_object *); +void spinlock_enter(void); +void spinlock_exit(void); +void witness_init(struct lock_object *, const char *); +void witness_destroy(struct lock_object *); +int witness_defineorder(struct lock_object *, struct lock_object *); +void witness_checkorder(struct lock_object *, int, const char *, int, + struct lock_object *); +void witness_lock(struct lock_object *, int, const char *, int); +void witness_upgrade(struct lock_object *, int, const char *, int); +void witness_downgrade(struct lock_object *, int, const char *, int); +void witness_unlock(struct lock_object *, int, const char *, int); +void witness_save(struct lock_object *, const char **, int *); +void witness_restore(struct lock_object *, const char *, int); +int witness_list_locks(struct lock_list_entry **, + int (*)(const char *, ...)); +int witness_warn(int, struct lock_object *, const char *, ...); +void witness_assert(struct lock_object *, int, const char *, int); +void witness_display_spinlock(struct lock_object *, struct thread *, + int (*)(const char *, ...)); +int witness_line(struct lock_object *); +void witness_norelease(struct lock_object *); +void witness_releaseok(struct lock_object *); +const char *witness_file(struct lock_object *); +void witness_thread_exit(struct thread *); + +#ifdef WITNESS + +/* Flags for witness_warn(). */ +#define WARN_GIANTOK 0x01 /* Giant is exempt from this check. */ +#define WARN_PANIC 0x02 /* Panic if check fails. */ +#define WARN_SLEEPOK 0x04 /* Sleepable locks are exempt from check. */ + +#define WITNESS_INIT(lock, type) \ + witness_init((lock), (type)) + +#define WITNESS_DESTROY(lock) \ + witness_destroy(lock) + +#define WITNESS_CHECKORDER(lock, flags, file, line, interlock) \ + witness_checkorder((lock), (flags), (file), (line), (interlock)) + +#define WITNESS_DEFINEORDER(lock1, lock2) \ + witness_defineorder((struct lock_object *)(lock1), \ + (struct lock_object *)(lock2)) + +#define WITNESS_LOCK(lock, flags, file, line) \ + witness_lock((lock), (flags), (file), (line)) + +#define WITNESS_UPGRADE(lock, flags, file, line) \ + witness_upgrade((lock), (flags), (file), (line)) + +#define WITNESS_DOWNGRADE(lock, flags, file, line) \ + witness_downgrade((lock), (flags), (file), (line)) + +#define WITNESS_UNLOCK(lock, flags, file, line) \ + witness_unlock((lock), (flags), (file), (line)) + +#define WITNESS_CHECK(flags, lock, fmt, ...) \ + witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) + +#define WITNESS_WARN(flags, lock, fmt, ...) \ + witness_warn((flags), (lock), (fmt), ## __VA_ARGS__) + +#define WITNESS_SAVE_DECL(n) \ + const char * __CONCAT(n, __wf); \ + int __CONCAT(n, __wl) + +#define WITNESS_SAVE(lock, n) \ + witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl)) + +#define WITNESS_RESTORE(lock, n) \ + witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl)) + +#define WITNESS_NORELEASE(lock) \ + witness_norelease(&(lock)->lock_object) + +#define WITNESS_RELEASEOK(lock) \ + witness_releaseok(&(lock)->lock_object) + +#define WITNESS_FILE(lock) \ + witness_file(lock) + +#define WITNESS_LINE(lock) \ + witness_line(lock) + +#else /* WITNESS */ +#define WITNESS_INIT(lock, type) (void)0 +#define WITNESS_DESTROY(lock) (void)0 +#define WITNESS_DEFINEORDER(lock1, lock2) 0 +#define WITNESS_CHECKORDER(lock, flags, file, line, interlock) (void)0 +#define WITNESS_LOCK(lock, flags, file, line) (void)0 +#define WITNESS_UPGRADE(lock, flags, file, line) (void)0 +#define WITNESS_DOWNGRADE(lock, flags, file, line) (void)0 +#define WITNESS_UNLOCK(lock, flags, file, line) (void)0 +#define WITNESS_CHECK(flags, lock, fmt, ...) 0 +#define WITNESS_WARN(flags, lock, fmt, ...) (void)0 +#define WITNESS_SAVE_DECL(n) (void)0 +#define WITNESS_SAVE(lock, n) (void)0 +#define WITNESS_RESTORE(lock, n) (void)0 +#define WITNESS_NORELEASE(lock) (void)0 +#define WITNESS_RELEASEOK(lock) (void)0 +#define WITNESS_FILE(lock) ("?") +#define WITNESS_LINE(lock) (0) +#endif /* WITNESS */ + +/* + * Helper macros to allow developers to add explicit lock order checks + * wherever they please without having to actually grab a lock to do so. + */ +#define witness_check(l) \ + WITNESS_CHECKORDER(&(l)->lock_object, LOP_EXCLUSIVE, LOCK_FILE, \ + LOCK_LINE, NULL) + +#define witness_check_shared(l) \ + WITNESS_CHECKORDER(&(l)->lock_object, 0, LOCK_FILE, LOCK_LINE, NULL) + +#endif /* _KERNEL */ +#endif /* _MACHINE__KERNEL_LOCK_H_ */ |