xnu-1699.22.73.tar.gz

[apple/xnu.git] / osfmk / kern / lock.h

diff --git a/osfmk/kern/lock.h b/osfmk/kern/lock.h
index 65cd1f18fcfa80df557466d1c29761731384783e..8366e26a6e0896006507ebf6d33a88f2ba624403 100644 (file)
--- a/osfmk/kern/lock.h
+++ b/osfmk/kern/lock.h
@@ -1,27 +1,29 @@
 /*
 /*

- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * 

- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.

  * 
  * 

- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER

  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.

  * 
  * 

- * @APPLE_LICENSE_HEADER_END@
- */
-/*
- * Copyright (C) 1998 Apple Computer
- * All Rights Reserved
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 /*
  * @OSF_COPYRIGHT@
  */
 /*
  * @OSF_COPYRIGHT@


@@ -59,217 +61,79 @@
  *     Higher Level Locking primitives definitions
  */
 
  *     Higher Level Locking primitives definitions
  */
 

+#ifdef KERNEL_PRIVATE
+

 #ifndef        _KERN_LOCK_H_
 #define        _KERN_LOCK_H_
 
 #ifndef        _KERN_LOCK_H_
 #define        _KERN_LOCK_H_
 

-/*
- * Configuration variables:
- *
- *
- *     MACH_LDEBUG:    record pc and thread of callers, turn on
- *                     all lock debugging.
- *
- *
- *     ETAP:           The Event Trace Analysis Package (ETAP) monitors
- *                     and records micro-kernel lock behavior and general
- *                     kernel events.  ETAP supports two levels of
- *                     tracing for locks:
- *                             - cumulative (ETAP_LOCK_ACCUMULATE)
- *                             - monitored  (ETAP_LOCK_MONITOR)
- *
- *                     Note: If either level of tracing is configured then
- *                           ETAP_LOCK_TRACE is automatically defined to 
- *                           equal one.
- *
- *                     Several macros are added throughout the lock code to
- *                      allow for convenient configuration.
- */
-

 #include <kern/simple_lock.h>
 #include <machine/lock.h>
 #include <kern/simple_lock.h>
 #include <machine/lock.h>

-#include <mach/etap_events.h>
-#include <mach/etap.h>
+#include <sys/cdefs.h>

 
 

-/*
- *     The Mach lock package exports the following high-level
- *      lock abstractions:
- *
- *     Lock Type  Properties
- *     mutex      blocking mutual exclusion lock, intended for
- *                SMP synchronization (vanishes on a uniprocessor);
- *                supports debugging, statistics, and pre-emption
- *     lock       blocking synchronization permitting multiple
- *                simultaneous readers or a single writer; supports
- *                debugging and statistics but not pre-emption
- *
- *     In general, mutex locks are preferred over all others, as the
- *     mutex supports pre-emption and relinquishes the processor
- *     upon contention.
- *
- */
+__BEGIN_DECLS

 
 

-/*
- *     A simple mutex lock.
- *     Do not change the order of the fields in this structure without
- *     changing the machine-dependent assembler routines which depend
- *     on them.
- */
-#ifdef MACH_KERNEL_PRIVATE
-#include <mach_ldebug.h>
-#include <kern/etap_options.h>
-#include <kern/etap_pool.h>
+#ifndef        MACH_KERNEL_PRIVATE

 
 

-typedef struct {
-       hw_lock_data_t  interlock;
-       hw_lock_data_t  locked;
-       short           waiters;
-#if    MACH_LDEBUG
-       int             type;
-#define        MUTEX_TAG       0x4d4d
-       vm_offset_t     pc;
-       vm_offset_t     thread;
-#endif /* MACH_LDEBUG */
-#if     ETAP_LOCK_TRACE
-       union {         /* Must be overlaid on the event_tablep */
-           struct event_table_chain event_table_chain;
-           struct {
-               event_table_t   event_tablep;     /* ptr to event table entry */
-               etap_time_t     start_hold_time;  /* Time of last acquistion */
-           } s;
-       } u;
-#endif         /* ETAP_LOCK_TRACE */
-#if     ETAP_LOCK_ACCUMULATE
-        cbuff_entry_t          cbuff_entry;      /* cumulative buffer entry          */
-#endif         /* ETAP_LOCK_ACCUMULATE */
-#if    ETAP_LOCK_MONITOR
-        vm_offset_t    start_pc;         /* pc where lock operation began    */
-        vm_offset_t    end_pc;           /* pc where lock operation ended    */
-#endif         /* ETAP_LOCK_MONITOR */
-} mutex_t;
-
-#define        decl_mutex_data(class,name)     class mutex_t name;
-#define mutex_addr(m)                  (&(m))
-
-#if    MACH_LDEBUG
-#define mutex_held(m) (hw_lock_held(&((m)->locked)) && \
-                      ((m)->thread == (int)current_thread()))
-#else  /* MACH_LDEBUG */
-#define mutex_held(m) hw_lock_held(&((m)->locked))
-#endif /* MACH_LDEBUG */
+typedef struct __lock__ lock_t;

 
 

-#else /* MACH_KERNEL_PRIVATE */
+#else  /* MACH_KERNEL_PRIVATE */

 
 

-typedef struct __mutex__ mutex_t;
-extern boolean_t mutex_held(mutex_t*);
+extern void                    lock_init(
+                                               lock_t          *lock,
+                                               boolean_t       can_sleep,
+                                               unsigned short  tag0,
+                                               unsigned short  tag1);

 
 

-#endif /* !MACH_KERNEL_PRIVATE */
+#endif /* MACH_KERNEL_PRIVATE */

 
 

-extern mutex_t *mutex_alloc            (etap_event_t);
-extern void    mutex_free              (mutex_t*);
+extern lock_t           *lock_alloc(
+                                               boolean_t       can_sleep, 
+                                               unsigned short  tag0, 
+                                               unsigned short  tag1);

 
 

-extern void    mutex_init              (mutex_t*, etap_event_t);
-extern void    _mutex_lock             (mutex_t*);
-extern void    mutex_unlock            (mutex_t*);
-extern boolean_t  _mutex_try           (mutex_t*);
+extern void                     lock_free(
+                                               lock_t          *lock);

 
 

-extern void    mutex_lock_wait         (mutex_t*);
-extern void    mutex_unlock_wakeup     (mutex_t*);
-extern void    mutex_pause             (void);
-extern void    interlock_unlock        (hw_lock_t);
+extern void                    lock_write(
+                                               lock_t          *lock);

 
 

-/*
- *     The general lock structure.  Provides for multiple readers,
- *     upgrading from read to write, and sleeping until the lock
- *     can be gained.
- *
- *     On some architectures, assembly language code in the 'inline'
- *     program fiddles the lock structures.  It must be changed in
- *     concert with the structure layout.
- *
- *     Only the "interlock" field is used for hardware exclusion;
- *     other fields are modified with normal instructions after
- *     acquiring the interlock bit.
- */
-#ifdef MACH_KERNEL_PRIVATE
-typedef struct {
-       decl_simple_lock_data(,interlock) /* "hardware" interlock field */
-       volatile unsigned int
-               read_count:16,  /* No. of accepted readers */
-               want_upgrade:1, /* Read-to-write upgrade waiting */
-               want_write:1,   /* Writer is waiting, or
-                                  locked for write */
-               waiting:1,      /* Someone is sleeping on lock */
-               can_sleep:1;    /* Can attempts to lock go to sleep? */
-#if     ETAP_LOCK_TRACE
-       union {         /* Must be overlaid on the event_tablep */
-           struct event_table_chain event_table_chain;
-           struct {
-               event_table_t event_tablep;     /* ptr to event table entry */
-               start_data_node_t start_list;   /* linked list of start times
-                                                  and pcs */
-           } s;
-       } u;
-#endif         /* ETAP_LOCK_TRACE */
-#if     ETAP_LOCK_ACCUMULATE
-               cbuff_entry_t   cbuff_write;    /* write cumulative buffer entry      */
-       cbuff_entry_t   cbuff_read;     /* read  cumulative buffer entry      */
-#endif         /* ETAP_LOCK_ACCUMULATE */
-} lock_t;
+extern void                    lock_read(
+                                               lock_t          *lock);

 
 

-/* Sleep locks must work even if no multiprocessing */
+extern void                    lock_done(
+                                               lock_t          *lock);

 
 

-/*
- * Complex lock operations
- */
+extern void                    lock_write_to_read(
+                                               lock_t          *lock);

 
 

-#if ETAP
-/*
- *     Locks have a pointer into an event_table entry that names the
- *     corresponding lock event and controls whether it is being traced.
- *     Initially this pointer is into a read-only table event_table_init[].
- *     Once dynamic allocation becomes possible a modifiable copy of the table
- *     is allocated and pointers are set to within this copy.  The pointers
- *     that were already in place at that point need to be switched to point
- *     into the copy.  To do this we overlay the event_table_chain structure
- *     onto sufficiently-big elements of the various lock structures so we
- *     can sweep down this list switching the pointers.  The assumption is
- *     that we will not want to enable tracing before this is done (which is
- *     after all during kernel bootstrap, before any user tasks are launched).
- *
- *     This is admittedly rather ugly but so were the alternatives:
- *     - record the event_table pointers in a statically-allocated array
- *       (dynamic allocation not yet being available) -- but there were
- *       over 8000 of them;
- *     - add a new link field to each lock structure;
- *     - change pointers to array indices -- this adds quite a bit of
- *       arithmetic to every lock operation that might be traced.
- */
-#define lock_event_table(lockp)                ((lockp)->u.s.event_tablep)
-#define lock_start_hold_time(lockp)    ((lockp)->u.s.start_hold_time)
-#endif /* ETAP_LOCK_TRACE */
+#define        lock_read_done(l)               lock_done(l)
+#define        lock_write_done(l)              lock_done(l)

 
 

-extern void    lock_init               (lock_t*,
-                                        boolean_t,
-                                        etap_event_t,
-                                        etap_event_t);
+extern boolean_t        lock_read_to_write(
+                                               lock_t          *lock);

 
 

-#else /* MACH_KERNEL_PRIVATE */

 
 

-typedef struct __lock__ lock_t;
-extern lock_t *lock_alloc(boolean_t, etap_event_t, etap_event_t);
-void lock_free(lock_t *);
+/* Sleep, unlocking and then relocking a usimple_lock in the process */
+extern wait_result_t   thread_sleep_usimple_lock(
+                                                       event_t                         event,
+                                                       usimple_lock_t          lock,
+                                                       wait_interrupt_t        interruptible);

 
 

-#endif /* !MACH_KERNEL_PRIVATE */
+/* Sleep, unlocking and then relocking a write lock in the process */
+extern wait_result_t   thread_sleep_lock_write(
+                                                       event_t                         event,
+                                                       lock_t                          *lock,
+                                                       wait_interrupt_t        interruptible);
+__END_DECLS

 
 

-extern void    lock_write              (lock_t*);
-extern void    lock_read               (lock_t*);
-extern void    lock_done               (lock_t*);
-extern void    lock_write_to_read      (lock_t*);
+#ifdef MACH_KERNEL_PRIVATE

 
 

-#define        lock_read_done(l)               lock_done(l)
-#define        lock_write_done(l)              lock_done(l)
-
-extern boolean_t lock_read_to_write    (lock_t*);  /* vm_map is only user */
-extern unsigned int LockTimeOut;                               /* Standard lock timeout value */
+extern wait_result_t   thread_sleep_fast_usimple_lock(
+                                                       event_t                                 event,
+                                                       simple_lock_t                   lock,
+                                                       wait_interrupt_t                 interruptible);
+#endif /* MACH_KERNEL_PRIVATE */

 
 #endif /* _KERN_LOCK_H_ */
 
 #endif /* _KERN_LOCK_H_ */

+
+#endif /* KERNEL_PRIVATE */