The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/sys/lock.h

Version: -  FREEBSD  -  FREEBSD11  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
    3  *
    4  * Redistribution and use in source and binary forms, with or without
    5  * modification, are permitted provided that the following conditions
    6  * are met:
    7  * 1. Redistributions of source code must retain the above copyright
    8  *    notice, this list of conditions and the following disclaimer.
    9  * 2. Redistributions in binary form must reproduce the above copyright
   10  *    notice, this list of conditions and the following disclaimer in the
   11  *    documentation and/or other materials provided with the distribution.
   12  * 3. Berkeley Software Design Inc's name may not be used to endorse or
   13  *    promote products derived from this software without specific prior
   14  *    written permission.
   15  *
   16  * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
   17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   19  * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
   20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   26  * SUCH DAMAGE.
   27  *
   28  *      from BSDI $Id: mutex.h,v 2.7.2.35 2000/04/27 03:10:26 cp Exp $
   29  * $FreeBSD: src/sys/sys/lock.h,v 1.50 2004/01/28 20:39:57 jhb Exp $
   30  */
   31 
   32 #ifndef _SYS_LOCK_H_
   33 #define _SYS_LOCK_H_
   34 
   35 #include <sys/queue.h>
   36 #include <sys/_lock.h>
   37 
   38 struct thread;
   39 
   40 /*
   41  * Lock classes.  Each lock has a class which describes characteristics
   42  * common to all types of locks of a given class.
   43  *
   44  * Spin locks in general must always protect against preemption, as it is
   45  * an error to perform any type of context switch while holding a spin lock.
   46  * Also, for an individual lock to be recursable, its class must allow
   47  * recursion and the lock itself must explicitly allow recursion.
   48  */
   49 
   50 struct lock_class {
   51         const   char *lc_name;
   52         u_int   lc_flags;
   53 };
   54 
   55 #define LC_SLEEPLOCK    0x00000001      /* Sleep lock. */
   56 #define LC_SPINLOCK     0x00000002      /* Spin lock. */
   57 #define LC_SLEEPABLE    0x00000004      /* Sleeping allowed with this lock. */
   58 #define LC_RECURSABLE   0x00000008      /* Locks of this type may recurse. */
   59 #define LC_UPGRADABLE   0x00000010      /* Upgrades and downgrades permitted. */
   60 
   61 #define LO_CLASSFLAGS   0x0000ffff      /* Class specific flags. */
   62 #define LO_INITIALIZED  0x00010000      /* Lock has been initialized. */
   63 #define LO_WITNESS      0x00020000      /* Should witness monitor this lock. */
   64 #define LO_QUIET        0x00040000      /* Don't log locking operations. */
   65 #define LO_RECURSABLE   0x00080000      /* Lock may recurse. */
   66 #define LO_SLEEPABLE    0x00100000      /* Lock may be held while sleeping. */
   67 #define LO_UPGRADABLE   0x00200000      /* Lock may be upgraded/downgraded. */
   68 #define LO_DUPOK        0x00400000      /* Don't check for duplicate acquires */
   69 
   70 #define LI_RECURSEMASK  0x0000ffff      /* Recursion depth of lock instance. */
   71 #define LI_EXCLUSIVE    0x00010000      /* Exclusive lock instance. */
   72 
   73 /*
   74  * Option flags passed to lock operations that witness also needs to know
   75  * about or that are generic across all locks.
   76  */
   77 #define LOP_NEWORDER    0x00000001      /* Define a new lock order. */
   78 #define LOP_QUIET       0x00000002      /* Don't log locking operations. */
   79 #define LOP_TRYLOCK     0x00000004      /* Don't check lock order. */
   80 #define LOP_EXCLUSIVE   0x00000008      /* Exclusive lock. */
   81 
   82 /* Flags passed to witness_assert. */
   83 #define LA_UNLOCKED     0x00000000      /* Lock is unlocked. */
   84 #define LA_LOCKED       0x00000001      /* Lock is at least share locked. */
   85 #define LA_SLOCKED      0x00000002      /* Lock is exactly share locked. */
   86 #define LA_XLOCKED      0x00000004      /* Lock is exclusively locked. */
   87 #define LA_RECURSED     0x00000008      /* Lock is recursed. */
   88 #define LA_NOTRECURSED  0x00000010      /* Lock is not recursed. */
   89 
   90 #ifdef _KERNEL
   91 /*
   92  * Lock instances.  A lock instance is the data associated with a lock while
   93  * it is held by witness.  For example, a lock instance will hold the
   94  * recursion count of a lock.  Lock instances are held in lists.  Spin locks
   95  * are held in a per-cpu list while sleep locks are held in per-process list.
   96  */
   97 struct lock_instance {
   98         struct  lock_object *li_lock;
   99         const   char *li_file;          /* File and line of last acquire. */
  100         int     li_line;
  101         u_int   li_flags;               /* Recursion count and LI_* flags. */
  102 };
  103 
  104 /*
  105  * A simple list type used to build the list of locks held by a process
  106  * or CPU.  We can't simply embed the list in struct lock_object since a
  107  * lock may be held by more than one process if it is a shared lock.  Locks
  108  * are added to the head of the list, so we fill up each list entry from
  109  * "the back" logically.  To ease some of the arithmetic, we actually fill
  110  * in each list entry the normal way (childer[0] then children[1], etc.) but
  111  * when we traverse the list we read children[count-1] as the first entry
  112  * down to children[0] as the final entry.
  113  */
  114 #define LOCK_NCHILDREN  3
  115 
  116 struct lock_list_entry {
  117         struct  lock_list_entry *ll_next;
  118         struct  lock_instance ll_children[LOCK_NCHILDREN];
  119         u_int   ll_count;
  120 };
  121 
  122 /*
  123  * If any of WITNESS, INVARIANTS, or KTR_LOCK KTR tracing has been enabled,
  124  * then turn on LOCK_DEBUG.  When this option is on, extra debugging
  125  * facilities such as tracking the file and line number of lock operations
  126  * are enabled.  Also, mutex locking operations are not inlined to avoid
  127  * bloat from all the extra debugging code.  We also have to turn on all the
  128  * calling conventions for this debugging code in modules so that modules can
  129  * work with both debug and non-debug kernels.
  130  */
  131 #if defined(KLD_MODULE) || defined(WITNESS) || defined(INVARIANTS) || defined(INVARIANT_SUPPORT) || defined(KTR) || defined(MUTEX_PROFILING)
  132 #define LOCK_DEBUG      1
  133 #else
  134 #define LOCK_DEBUG      0
  135 #endif
  136 
  137 /*
  138  * In the LOCK_DEBUG case, use the filename and line numbers for debugging
  139  * operations.  Otherwise, use default values to avoid the unneeded bloat.
  140  */
  141 #if LOCK_DEBUG > 0
  142 #define LOCK_FILE       __FILE__
  143 #define LOCK_LINE       __LINE__
  144 #else
  145 #define LOCK_FILE       NULL
  146 #define LOCK_LINE       0
  147 #endif
  148 
  149 /*
  150  * Macros for KTR_LOCK tracing.
  151  *
  152  * opname  - name of this operation (LOCK/UNLOCK/SLOCK, etc.)
  153  * lo      - struct lock_object * for this lock
  154  * flags   - flags passed to the lock operation
  155  * recurse - this locks recursion level (or 0 if class is not recursable)
  156  * result  - result of a try lock operation
  157  * file    - file name
  158  * line    - line number
  159  */
  160 #define LOCK_LOG_TEST(lo, flags)                                        \
  161         (((flags) & LOP_QUIET) == 0 && ((lo)->lo_flags & LO_QUIET) == 0)
  162 
  163 #define LOCK_LOG_LOCK(opname, lo, flags, recurse, file, line) do {      \
  164         if (LOCK_LOG_TEST((lo), (flags)))                               \
  165                 CTR5(KTR_LOCK, opname " (%s) %s r = %d at %s:%d",       \
  166                     (lo)->lo_class->lc_name, (lo)->lo_name,             \
  167                     (u_int)(recurse), (file), (line));                  \
  168 } while (0)
  169 
  170 #define LOCK_LOG_TRY(opname, lo, flags, result, file, line) do {        \
  171         if (LOCK_LOG_TEST((lo), (flags)))                               \
  172                 CTR5(KTR_LOCK, "TRY_" opname " (%s) %s result=%d at %s:%d",\
  173                     (lo)->lo_class->lc_name, (lo)->lo_name,             \
  174                     (u_int)(result), (file), (line));                   \
  175 } while (0)
  176 
  177 #define LOCK_LOG_INIT(lo, flags) do {                                   \
  178         if (LOCK_LOG_TEST((lo), (flags)))                               \
  179                 CTR4(KTR_LOCK, "%s: %p (%s) %s", __func__, (lo),        \
  180                     (lo)->lo_class->lc_name, (lo)->lo_name);            \
  181 } while (0)
  182 
  183 #define LOCK_LOG_DESTROY(lo, flags)     LOCK_LOG_INIT(lo, flags)
  184 
  185 /*
  186  * Helpful macros for quickly coming up with assertions with informative
  187  * panic messages.
  188  */
  189 #define MPASS(ex)               MPASS4(ex, #ex, __FILE__, __LINE__)
  190 #define MPASS2(ex, what)        MPASS4(ex, what, __FILE__, __LINE__)
  191 #define MPASS3(ex, file, line)  MPASS4(ex, #ex, file, line)
  192 #define MPASS4(ex, what, file, line)                                    \
  193         KASSERT((ex), ("Assertion %s failed at %s:%d", what, file, line))
  194 
  195 extern struct lock_class lock_class_mtx_sleep;
  196 extern struct lock_class lock_class_mtx_spin;
  197 extern struct lock_class lock_class_sx;
  198 
  199 void    witness_init(struct lock_object *);
  200 void    witness_destroy(struct lock_object *);
  201 int     witness_defineorder(struct lock_object *, struct lock_object *);
  202 void    witness_checkorder(struct lock_object *, int, const char *, int);
  203 void    witness_lock(struct lock_object *, int, const char *, int);
  204 void    witness_upgrade(struct lock_object *, int, const char *, int);
  205 void    witness_downgrade(struct lock_object *, int, const char *, int);
  206 void    witness_unlock(struct lock_object *, int, const char *, int);
  207 void    witness_save(struct lock_object *, const char **, int *);
  208 void    witness_restore(struct lock_object *, const char *, int);
  209 int     witness_list_locks(struct lock_list_entry **);
  210 int     witness_warn(int, struct lock_object *, const char *, ...);
  211 void    witness_assert(struct lock_object *, int, const char *, int);
  212 void    witness_display_spinlock(struct lock_object *, struct thread *);
  213 int     witness_line(struct lock_object *);
  214 const char *witness_file(struct lock_object *);
  215 
  216 #ifdef  WITNESS
  217 
  218 /* Flags for witness_warn(). */
  219 #define WARN_GIANTOK    0x01    /* Giant is exempt from this check. */
  220 #define WARN_PANIC      0x02    /* Panic if check fails. */
  221 #define WARN_SLEEPOK    0x04    /* Sleepable locks are exempt from check. */
  222 
  223 #define WITNESS_INIT(lock)                                              \
  224         witness_init((lock))
  225 
  226 #define WITNESS_DESTROY(lock)                                           \
  227         witness_destroy(lock)
  228 
  229 #define WITNESS_CHECKORDER(lock, flags, file, line)                     \
  230         witness_checkorder((lock), (flags), (file), (line))
  231 
  232 #define WITNESS_DEFINEORDER(lock1, lock2)                               \
  233         witness_defineorder((struct lock_object *)(lock1),              \
  234             (struct lock_object *)(lock2))
  235 
  236 #define WITNESS_LOCK(lock, flags, file, line)                           \
  237         witness_lock((lock), (flags), (file), (line))
  238 
  239 #define WITNESS_UPGRADE(lock, flags, file, line)                        \
  240         witness_upgrade((lock), (flags), (file), (line))
  241 
  242 #define WITNESS_DOWNGRADE(lock, flags, file, line)                      \
  243         witness_downgrade((lock), (flags), (file), (line))
  244 
  245 #define WITNESS_UNLOCK(lock, flags, file, line)                         \
  246         witness_unlock((lock), (flags), (file), (line))
  247 
  248 #define WITNESS_WARN(flags, lock, fmt, ...)                             \
  249         witness_warn((flags), (lock), (fmt), ## __VA_ARGS__)
  250 
  251 #define WITNESS_SAVE_DECL(n)                                            \
  252         const char * __CONCAT(n, __wf);                                 \
  253         int __CONCAT(n, __wl)
  254 
  255 #define WITNESS_SAVE(lock, n)                                           \
  256         witness_save((lock), &__CONCAT(n, __wf), &__CONCAT(n, __wl))
  257 
  258 #define WITNESS_RESTORE(lock, n)                                        \
  259         witness_restore((lock), __CONCAT(n, __wf), __CONCAT(n, __wl))
  260 
  261 #define WITNESS_FILE(lock)                                              \
  262         witness_file(lock)
  263 
  264 #define WITNESS_LINE(lock)                                              \
  265         witness_line(lock)
  266 
  267 #else   /* WITNESS */
  268 #define WITNESS_INIT(lock)      ((lock)->lo_flags |= LO_INITIALIZED)
  269 #define WITNESS_DESTROY(lock)   ((lock)->lo_flags &= ~LO_INITIALIZED)
  270 #define WITNESS_DEFINEORDER(lock1, lock2)       0
  271 #define WITNESS_CHECKORDER(lock, flags, file, line)
  272 #define WITNESS_LOCK(lock, flags, file, line)
  273 #define WITNESS_UPGRADE(lock, flags, file, line)
  274 #define WITNESS_DOWNGRADE(lock, flags, file, line)
  275 #define WITNESS_UNLOCK(lock, flags, file, line)
  276 #define WITNESS_WARN(flags, lock, fmt, ...)
  277 #define WITNESS_SAVE_DECL(n)
  278 #define WITNESS_SAVE(lock, n)
  279 #define WITNESS_RESTORE(lock, n)
  280 #define WITNESS_FILE(lock) ("?")
  281 #define WITNESS_LINE(lock) (0)
  282 #endif  /* WITNESS */
  283 
  284 /*
  285  * Helper macros to allow developers to add explicit lock order checks
  286  * wherever they please without having to actually grab a lock to do so.
  287  */
  288 #define witness_check_mutex(m)                                          \
  289         WITNESS_CHECKORDER(&(m)->mtx_object, LOP_EXCLUSIVE, LOCK_FILE,  \
  290             LOCK_LINE)
  291 
  292 #define witness_check_shared_sx(sx)                                     \
  293         WITNESS_CHECKORDER(&(sx)->sx_object, 0, LOCK_FILE, LOCK_LINE)
  294         
  295 #define witness_check_exclusive_sx(sx)                                  \
  296         WITNESS_CHECKORDER(&(sx)->sx_object, LOP_EXCLUSIVE, LOCK_FILE,  \
  297             LOCK_LINE)
  298 
  299 #endif  /* _KERNEL */
  300 #endif  /* _SYS_LOCK_H_ */

Cache object: 7279f433ccb2ee567c08824b3ab74ef7


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.