-#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 <mach/etap_events.h>
-#include <mach/etap.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.
- *
- */
-
-/*
- * 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>
-
-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))
-
-extern void mutex_init (mutex_t*, etap_event_t);
-extern void mutex_lock_wait (mutex_t*);
-extern void mutex_unlock_wakeup (mutex_t*);
-extern void interlock_unlock (hw_lock_t);
-
-#else /* MACH_KERNEL_PRIVATE */
-
-typedef struct __mutex__ mutex_t;
-
-/* going away */
-extern void _mutex_lock (mutex_t*);
-extern boolean_t _mutex_try (mutex_t*);
-
-#endif /* !MACH_KERNEL_PRIVATE */
-
-extern mutex_t *mutex_alloc (etap_event_t);
-extern void mutex_free (mutex_t*);
-extern void mutex_lock (mutex_t*);
-extern void mutex_unlock (mutex_t*);
-extern boolean_t mutex_try (mutex_t*);
-
-extern void mutex_pause (void);
-
-/*
- * 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;
-
-/* Sleep locks must work even if no multiprocessing */
-
-/*
- * Complex lock operations
- */
-
-#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 */
-
-extern void lock_init (lock_t*,
- boolean_t,
- etap_event_t,
- etap_event_t);
-
-#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 *);
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