/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2012 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* 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. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * 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.
+ *
+ * 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
* Please see the License for the specific language governing rights and
* limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
* the terms and conditions for use and redistribution.
*/
-#include <mach_rt.h>
-#include <platforms.h>
#include <mach_ldebug.h>
#include <i386/asm.h>
-
+#include <i386/eflags.h>
+#include <i386/trap.h>
+#include <config_dtrace.h>
+#include <i386/mp.h>
+
#include "assym.s"
#define PAUSE rep; nop
-/*
- * When performance isn't the only concern, it's
- * nice to build stack frames...
- */
-#define BUILD_STACK_FRAMES (GPROF || \
- ((MACH_LDEBUG || ETAP_LOCK_TRACE) && MACH_KDB))
-
-#if BUILD_STACK_FRAMES
-
-/* STack-frame-relative: */
-#define L_PC B_PC
-#define L_ARG0 B_ARG0
-#define L_ARG1 B_ARG1
-
-#define LEAF_ENTRY(name) \
- Entry(name); \
- FRAME; \
- MCOUNT
-
-#define LEAF_ENTRY2(n1,n2) \
- Entry(n1); \
- Entry(n2); \
- FRAME; \
- MCOUNT
-
-#define LEAF_RET \
- EMARF; \
- ret
-
-#else /* BUILD_STACK_FRAMES */
-
-/* Stack-pointer-relative: */
-#define L_PC S_PC
-#define L_ARG0 S_ARG0
-#define L_ARG1 S_ARG1
+#include <i386/pal_lock_asm.h>
#define LEAF_ENTRY(name) \
Entry(name)
#define LEAF_RET \
ret
-#endif /* BUILD_STACK_FRAMES */
-
-
/* Non-leaf routines always have a stack frame: */
#define NONLEAF_ENTRY(name) \
Entry(name); \
- FRAME; \
- MCOUNT
+ FRAME
#define NONLEAF_ENTRY2(n1,n2) \
Entry(n1); \
Entry(n2); \
- FRAME; \
- MCOUNT
+ FRAME
#define NONLEAF_RET \
EMARF; \
ret
-#define M_ILK (%edx)
-#define M_LOCKED MUTEX_LOCKED(%edx)
-#define M_WAITERS MUTEX_WAITERS(%edx)
-#define M_PROMOTED_PRI MUTEX_PROMOTED_PRI(%edx)
-#define M_ITAG MUTEX_ITAG(%edx)
-#define M_PTR MUTEX_PTR(%edx)
-#if MACH_LDEBUG
-#define M_TYPE MUTEX_TYPE(%edx)
-#define M_PC MUTEX_PC(%edx)
-#define M_THREAD MUTEX_THREAD(%edx)
-#endif /* MACH_LDEBUG */
+/* For x86_64, the varargs ABI requires that %al indicate
+ * how many SSE register contain arguments. In our case, 0 */
+#define ALIGN_STACK() and $0xFFFFFFFFFFFFFFF0, %rsp ;
+#define LOAD_STRING_ARG0(label) leaq label(%rip), %rdi ;
+#define LOAD_ARG1(x) mov x, %esi ;
+#define LOAD_PTR_ARG1(x) mov x, %rsi ;
+#define CALL_PANIC() xorb %al,%al ; call EXT(panic) ;
-#include <i386/mp.h>
-#define CX(addr,reg) addr(,reg,4)
+#define CHECK_UNLOCK(current, owner) \
+ cmp current, owner ; \
+ je 1f ; \
+ ALIGN_STACK() ; \
+ LOAD_STRING_ARG0(2f) ; \
+ CALL_PANIC() ; \
+ hlt ; \
+ .data ; \
+2: String "Mutex unlock attempted from non-owner thread"; \
+ .text ; \
+1:
#if MACH_LDEBUG
/*
* Routines for general lock debugging.
*/
-#define S_TYPE SLOCK_TYPE(%edx)
-#define S_PC SLOCK_PC(%edx)
-#define S_THREAD SLOCK_THREAD(%edx)
-#define S_DURATIONH SLOCK_DURATIONH(%edx)
-#define S_DURATIONL SLOCK_DURATIONL(%edx)
/*
* Checks for expected lock types and calls "panic" on
#define CHECK_MUTEX_TYPE() \
cmpl $ MUTEX_TAG,M_TYPE ; \
je 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
+ ALIGN_STACK() ; \
+ LOAD_STRING_ARG0(2f) ; \
+ CALL_PANIC() ; \
hlt ; \
.data ; \
2: String "not a mutex!" ; \
.text ; \
1:
-#define CHECK_SIMPLE_LOCK_TYPE() \
- cmpl $ USLOCK_TAG,S_TYPE ; \
- je 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
+#define CHECK_MYLOCK(current, owner) \
+ cmp current, owner ; \
+ jne 1f ; \
+ ALIGN_STACK() ; \
+ LOAD_STRING_ARG0(2f) ; \
+ CALL_PANIC() ; \
hlt ; \
.data ; \
-2: String "not a simple lock!" ; \
+2: String "Attempt to recursively lock a non-recursive lock"; \
.text ; \
1:
+#else /* MACH_LDEBUG */
+#define CHECK_MUTEX_TYPE()
+#define CHECK_MYLOCK(thd)
+#endif /* MACH_LDEBUG */
+
+#if DEVELOPMENT || DEBUG
/*
* If one or more simplelocks are currently held by a thread,
* an attempt to acquire a mutex will cause this check to fail
* (since a mutex lock may context switch, holding a simplelock
* is not a good thing).
*/
-#if MACH_RT
#define CHECK_PREEMPTION_LEVEL() \
cmpl $0,%gs:CPU_PREEMPTION_LEVEL ; \
je 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
- hlt ; \
- .data ; \
-2: String "preemption_level != 0!" ; \
- .text ; \
-1:
-#else /* MACH_RT */
-#define CHECK_PREEMPTION_LEVEL()
-#endif /* MACH_RT */
-
-#define CHECK_NO_SIMPLELOCKS() \
- cmpl $0,%gs:CPU_SIMPLE_LOCK_COUNT ; \
- je 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
+ cmpl $0,EXT(LckDisablePreemptCheck)(%rip) ; \
+ jne 1f ; \
+ cmpl $0,%gs:CPU_HIBERNATE ; \
+ jne 1f ; \
+ ALIGN_STACK() ; \
+ movl %gs:CPU_PREEMPTION_LEVEL, %eax ; \
+ LOAD_ARG1(%eax) ; \
+ LOAD_STRING_ARG0(2f) ; \
+ CALL_PANIC() ; \
hlt ; \
.data ; \
-2: String "simple_locks_held!" ; \
+2: String "preemption_level(%d) != 0!" ; \
.text ; \
1:
+#else /* DEVELOPMENT || DEBUG */
+#define CHECK_PREEMPTION_LEVEL()
+#endif /* DEVELOPMENT || DEBUG */
+
+#define PREEMPTION_DISABLE \
+ incl %gs:CPU_PREEMPTION_LEVEL
+
+#define PREEMPTION_LEVEL_DEBUG 1
+#if PREEMPTION_LEVEL_DEBUG
+#define PREEMPTION_ENABLE \
+ decl %gs:CPU_PREEMPTION_LEVEL ; \
+ js 17f ; \
+ jnz 19f ; \
+ testl $AST_URGENT,%gs:CPU_PENDING_AST ; \
+ jz 19f ; \
+ PUSHF ; \
+ testl $EFL_IF, S_PC ; \
+ jz 18f ; \
+ POPF ; \
+ int $(T_PREEMPT) ; \
+ jmp 19f ; \
+17: \
+ call _preemption_underflow_panic ; \
+18: \
+ POPF ; \
+19:
+#else
+#define PREEMPTION_ENABLE \
+ decl %gs:CPU_PREEMPTION_LEVEL ; \
+ jnz 19f ; \
+ testl $AST_URGENT,%gs:CPU_PENDING_AST ; \
+ jz 19f ; \
+ PUSHF ; \
+ testl $EFL_IF, S_PC ; \
+ jz 18f ; \
+ POPF ; \
+ int $(T_PREEMPT) ; \
+ jmp 19f ; \
+18: \
+ POPF ; \
+19:
+#endif
-/*
- * Verifies return to the correct thread in "unlock" situations.
- */
-#define CHECK_THREAD(thd) \
- movl %gs:CPU_ACTIVE_THREAD,%ecx ; \
- testl %ecx,%ecx ; \
- je 1f ; \
- cmpl %ecx,thd ; \
- je 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
- hlt ; \
- .data ; \
-2: String "wrong thread!" ; \
- .text ; \
-1:
-#define CHECK_MYLOCK(thd) \
- movl %gs:CPU_ACTIVE_THREAD,%ecx ; \
- testl %ecx,%ecx ; \
- je 1f ; \
- cmpl %ecx,thd ; \
- jne 1f ; \
- pushl $2f ; \
- call EXT(panic) ; \
- hlt ; \
- .data ; \
-2: String "mylock attempt!" ; \
- .text ; \
-1:
+#if CONFIG_DTRACE
-#define METER_SIMPLE_LOCK_LOCK(reg) \
- pushl reg ; \
- call EXT(meter_simple_lock) ; \
- popl reg
+ .globl _lockstat_probe
+ .globl _lockstat_probemap
-#define METER_SIMPLE_LOCK_UNLOCK(reg) \
- pushl reg ; \
- call EXT(meter_simple_unlock) ; \
- popl reg
+/*
+ * LOCKSTAT_LABEL creates a dtrace symbol which contains
+ * a pointer into the lock code function body. At that
+ * point is a "ret" instruction that can be patched into
+ * a "nop"
+ */
-#else /* MACH_LDEBUG */
-#define CHECK_MUTEX_TYPE()
-#define CHECK_SIMPLE_LOCK_TYPE
-#define CHECK_THREAD(thd)
-#define CHECK_PREEMPTION_LEVEL()
-#define CHECK_NO_SIMPLELOCKS()
-#define CHECK_MYLOCK(thd)
-#define METER_SIMPLE_LOCK_LOCK(reg)
-#define METER_SIMPLE_LOCK_UNLOCK(reg)
-#endif /* MACH_LDEBUG */
+#define LOCKSTAT_LABEL(lab) \
+ .data ;\
+ .globl lab ;\
+ lab: ;\
+ .quad 9f ;\
+ .text ;\
+ 9:
+
+#define LOCKSTAT_RECORD(id, lck) \
+ push %rbp ; \
+ mov %rsp,%rbp ; \
+ movl _lockstat_probemap + (id * 4)(%rip),%eax ; \
+ test %eax,%eax ; \
+ je 9f ; \
+ mov lck, %rsi ; \
+ mov %rax, %rdi ; \
+ mov $0, %rdx ; \
+ mov $0, %rcx ; \
+ mov $0, %r8 ; \
+ mov $0, %r9 ; \
+ call *_lockstat_probe(%rip) ; \
+9: leave
+ /* ret - left to subsequent code, e.g. return values */
+
+#endif /* CONFIG_DTRACE */
+/*
+ * For most routines, the hw_lock_t pointer is loaded into a
+ * register initially, and then either a byte or register-sized
+ * word is loaded/stored to the pointer
+ */
/*
- * void hw_lock_init(hw_lock_t)
+ * void hw_lock_byte_init(volatile uint8_t *)
*
- * Initialize a hardware lock.
+ * Initialize a hardware byte lock.
*/
-LEAF_ENTRY(hw_lock_init)
- movl L_ARG0,%edx /* fetch lock pointer */
- movl $0,0(%edx) /* clear the lock */
+LEAF_ENTRY(hw_lock_byte_init)
+ movb $0, (%rdi) /* clear the lock */
LEAF_RET
/*
- * void hw_lock_lock(hw_lock_t)
+ * void hw_lock_byte_lock(uint8_t *lock_byte)
*
- * Acquire lock, spinning until it becomes available.
- * MACH_RT: also return with preemption disabled.
+ * Acquire byte sized lock operand, spinning until it becomes available.
+ * return with preemption disabled.
*/
-LEAF_ENTRY(hw_lock_lock)
- movl L_ARG0,%edx /* fetch lock pointer */
- movl L_PC,%ecx
-1: DISABLE_PREEMPTION
- movl 0(%edx), %eax
- testl %eax,%eax /* lock locked? */
+LEAF_ENTRY(hw_lock_byte_lock)
+ PREEMPTION_DISABLE
+ movl $1, %ecx /* Set lock value */
+1:
+ movb (%rdi), %al /* Load byte at address */
+ testb %al,%al /* lock locked? */
jne 3f /* branch if so */
- lock; cmpxchgl %ecx,0(%edx) /* try to acquire the HW lock */
+ lock; cmpxchg %cl,(%rdi) /* attempt atomic compare exchange */
jne 3f
- movl $1,%eax /* In case this was a timeout call */
LEAF_RET /* if yes, then nothing left to do */
-
-3: ENABLE_PREEMPTION /* no reason we can't be preemptable */
+3:
PAUSE /* pause for hyper-threading */
jmp 1b /* try again */
/*
- * unsigned int hw_lock_to(hw_lock_t, unsigned int)
+ * void hw_lock_byte_unlock(uint8_t *lock_byte)
*
- * Acquire lock, spinning until it becomes available or timeout.
- * MACH_RT: also return with preemption disabled.
+ * Unconditionally release byte sized lock operand,
+ * release preemption level.
*/
-LEAF_ENTRY(hw_lock_to)
-1:
- movl L_ARG0,%edx /* fetch lock pointer */
- movl L_PC,%ecx
- /*
- * Attempt to grab the lock immediately
- * - fastpath without timeout nonsense.
- */
- DISABLE_PREEMPTION
- movl 0(%edx), %eax
- testl %eax,%eax /* lock locked? */
- jne 2f /* branch if so */
- lock; cmpxchgl %ecx,0(%edx) /* try to acquire the HW lock */
- jne 2f /* branch on failure */
- movl $1,%eax
- LEAF_RET
-
-2:
-#define INNER_LOOP_COUNT 1000
- /*
- * Failed to get the lock so set the timeout
- * and then spin re-checking the lock but pausing
- * every so many (INNER_LOOP_COUNT) spins to check for timeout.
- */
- movl L_ARG1,%ecx /* fetch timeout */
- push %edi
- push %ebx
- mov %edx,%edi
-
- rdtsc /* read cyclecount into %edx:%eax */
- addl %ecx,%eax /* fetch and timeout */
- adcl $0,%edx /* add carry */
- mov %edx,%ecx
- mov %eax,%ebx /* %ecx:%ebx is the timeout expiry */
-3:
- ENABLE_PREEMPTION /* no reason not to be preempted now */
-4:
- /*
- * The inner-loop spin to look for the lock being freed.
- */
- mov $(INNER_LOOP_COUNT),%edx
-5:
- PAUSE /* pause for hyper-threading */
- movl 0(%edi),%eax /* spin checking lock value in cache */
- testl %eax,%eax
- je 6f /* zero => unlocked, try to grab it */
- decl %edx /* decrement inner loop count */
- jnz 5b /* time to check for timeout? */
-
- /*
- * Here after spinning INNER_LOOP_COUNT times, check for timeout
- */
- rdtsc /* cyclecount into %edx:%eax */
- cmpl %ecx,%edx /* compare high-order 32-bits */
- jb 4b /* continue spinning if less, or */
- cmpl %ebx,%eax /* compare low-order 32-bits */
- jb 5b /* continue if less, else bail */
- xor %eax,%eax /* with 0 return value */
- pop %ebx
- pop %edi
- LEAF_RET
-6:
- /*
- * Here to try to grab the lock that now appears to be free
- * after contention.
- */
- movl 8+L_PC,%edx /* calling pc (8+ for pushed regs) */
- DISABLE_PREEMPTION
- lock; cmpxchgl %edx,0(%edi) /* try to acquire the HW lock */
- jne 3b /* no - spin again */
- movl $1,%eax /* yes */
- pop %ebx
- pop %edi
+LEAF_ENTRY(hw_lock_byte_unlock)
+ movb $0, (%rdi) /* Clear the lock byte */
+ PREEMPTION_ENABLE
LEAF_RET
-
+
/*
- * void hw_lock_unlock(hw_lock_t)
+ * N.B.: On x86, statistics are currently recorded for all indirect mutexes.
+ * Also, only the acquire attempt count (GRP_MTX_STAT_UTIL) is maintained
+ * as a 64-bit quantity (this matches the existing PowerPC implementation,
+ * and the new x86 specific statistics are also maintained as 32-bit
+ * quantities).
*
- * Unconditionally release lock.
- * MACH_RT: release preemption level.
+ *
+ * Enable this preprocessor define to record the first miss alone
+ * By default, we count every miss, hence multiple misses may be
+ * recorded for a single lock acquire attempt via lck_mtx_lock
*/
-LEAF_ENTRY(hw_lock_unlock)
- movl L_ARG0,%edx /* fetch lock pointer */
- movl $0,0(%edx) /* clear the lock */
- ENABLE_PREEMPTION
- LEAF_RET
+#undef LOG_FIRST_MISS_ALONE
/*
- * unsigned int hw_lock_try(hw_lock_t)
- * MACH_RT: returns with preemption disabled on success.
+ * This preprocessor define controls whether the R-M-W update of the
+ * per-group statistics elements are atomic (LOCK-prefixed)
+ * Enabled by default.
*/
-LEAF_ENTRY(hw_lock_try)
- movl L_ARG0,%edx /* fetch lock pointer */
-
- movl L_PC,%ecx
- DISABLE_PREEMPTION
- movl 0(%edx),%eax
- testl %eax,%eax
- jne 1f
- lock; cmpxchgl %ecx,0(%edx) /* try to acquire the HW lock */
- jne 1f
-
- movl $1,%eax /* success */
- LEAF_RET
+#define ATOMIC_STAT_UPDATES 1
+
+#if defined(ATOMIC_STAT_UPDATES)
+#define LOCK_IF_ATOMIC_STAT_UPDATES lock
+#else
+#define LOCK_IF_ATOMIC_STAT_UPDATES
+#endif /* ATOMIC_STAT_UPDATES */
-1: ENABLE_PREEMPTION /* failure: release preemption... */
- xorl %eax,%eax /* ...and return failure */
- LEAF_RET
/*
- * unsigned int hw_lock_held(hw_lock_t)
- * MACH_RT: doesn't change preemption state.
- * N.B. Racy, of course.
+ * For most routines, the lck_mtx_t pointer is loaded into a
+ * register initially, and the owner field checked for indirection.
+ * Eventually the lock owner is loaded into a register and examined.
*/
-LEAF_ENTRY(hw_lock_held)
- movl L_ARG0,%edx /* fetch lock pointer */
- movl 0(%edx),%eax /* check lock value */
- testl %eax,%eax
- movl $1,%ecx
- cmovne %ecx,%eax /* 0 => unlocked, 1 => locked */
- LEAF_RET
+#define M_OWNER MUTEX_OWNER
+#define M_PTR MUTEX_PTR
+#define M_STATE MUTEX_STATE
+
-LEAF_ENTRY(mutex_init)
- movl L_ARG0,%edx /* fetch lock pointer */
- xorl %eax,%eax
- movl %eax,M_ILK /* clear interlock */
- movl %eax,M_LOCKED /* clear locked flag */
- movw %ax,M_WAITERS /* init waiter count */
- movw %ax,M_PROMOTED_PRI
+#define LMTX_ENTER_EXTENDED \
+ mov M_PTR(%rdx), %rdx ; \
+ xor %r11, %r11 ; \
+ mov MUTEX_GRP(%rdx), %r10 ; \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incq GRP_MTX_STAT_UTIL(%r10)
+
+
+#if LOG_FIRST_MISS_ALONE
+#define LMTX_UPDATE_MISS \
+ test $1, %r11 ; \
+ jnz 11f ; \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incl GRP_MTX_STAT_MISS(%r10) ; \
+ or $1, %r11 ; \
+11:
+#else
+#define LMTX_UPDATE_MISS \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incl GRP_MTX_STAT_MISS(%r10)
+#endif
+
-#if MACH_LDEBUG
- movl $ MUTEX_TAG,M_TYPE /* set lock type */
- movl %eax,M_PC /* init caller pc */
- movl %eax,M_THREAD /* and owning thread */
+#if LOG_FIRST_MISS_ALONE
+#define LMTX_UPDATE_WAIT \
+ test $2, %r11 ; \
+ jnz 11f ; \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incl GRP_MTX_STAT_WAIT(%r10) ; \
+ or $2, %r11 ; \
+11:
+#else
+#define LMTX_UPDATE_WAIT \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incl GRP_MTX_STAT_WAIT(%r10)
#endif
- LEAF_RET
-NONLEAF_ENTRY2(mutex_lock,_mutex_lock)
+/*
+ * Record the "direct wait" statistic, which indicates if a
+ * miss proceeded to block directly without spinning--occurs
+ * if the owner of the mutex isn't running on another processor
+ * at the time of the check.
+ */
+#define LMTX_UPDATE_DIRECT_WAIT \
+ LOCK_IF_ATOMIC_STAT_UPDATES ; \
+ incl GRP_MTX_STAT_DIRECT_WAIT(%r10)
- movl B_ARG0,%edx /* fetch lock pointer */
+
+#define LMTX_CALLEXT1(func_name) \
+ cmp %rdx, %rdi ; \
+ je 12f ; \
+ push %r10 ; \
+ push %r11 ; \
+12: push %rdi ; \
+ push %rdx ; \
+ mov %rdx, %rdi ; \
+ call EXT(func_name) ; \
+ pop %rdx ; \
+ pop %rdi ; \
+ cmp %rdx, %rdi ; \
+ je 12f ; \
+ pop %r11 ; \
+ pop %r10 ; \
+12:
+
+#define LMTX_CALLEXT2(func_name, reg) \
+ cmp %rdx, %rdi ; \
+ je 12f ; \
+ push %r10 ; \
+ push %r11 ; \
+12: push %rdi ; \
+ push %rdx ; \
+ mov reg, %rsi ; \
+ mov %rdx, %rdi ; \
+ call EXT(func_name) ; \
+ pop %rdx ; \
+ pop %rdi ; \
+ cmp %rdx, %rdi ; \
+ je 12f ; \
+ pop %r11 ; \
+ pop %r10 ; \
+12:
+
+
+#define M_WAITERS_MSK 0x0000ffff
+#define M_PRIORITY_MSK 0x00ff0000
+#define M_ILOCKED_MSK 0x01000000
+#define M_MLOCKED_MSK 0x02000000
+#define M_PROMOTED_MSK 0x04000000
+#define M_SPIN_MSK 0x08000000
- CHECK_MUTEX_TYPE()
- CHECK_NO_SIMPLELOCKS()
- CHECK_PREEMPTION_LEVEL()
+/*
+ * void lck_mtx_assert(lck_mtx_t* l, unsigned int)
+ * Takes the address of a lock, and an assertion type as parameters.
+ * The assertion can take one of two forms determine by the type
+ * parameter: either the lock is held by the current thread, and the
+ * type is LCK_MTX_ASSERT_OWNED, or it isn't and the type is
+ * LCK_MTX_ASSERT_NOTOWNED. Calls panic on assertion failure.
+ *
+ */
- pushf /* save interrupt state */
- cli /* disable interrupts */
+NONLEAF_ENTRY(lck_mtx_assert)
+ mov %rdi, %rdx /* Load lock address */
+ mov %gs:CPU_ACTIVE_THREAD, %rax /* Load current thread */
+
+ mov M_STATE(%rdx), %ecx
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne 0f
+ mov M_PTR(%rdx), %rdx /* If so, take indirection */
+0:
+ mov M_OWNER(%rdx), %rcx /* Load owner */
+ cmp $(MUTEX_ASSERT_OWNED), %rsi
+ jne 2f /* Assert ownership? */
+ cmp %rax, %rcx /* Current thread match? */
+ jne 3f /* no, go panic */
+ testl $(M_ILOCKED_MSK | M_MLOCKED_MSK), M_STATE(%rdx)
+ je 3f
+1: /* yes, we own it */
+ NONLEAF_RET
+2:
+ cmp %rax, %rcx /* Current thread match? */
+ jne 1b /* No, return */
+ ALIGN_STACK()
+ LOAD_PTR_ARG1(%rdx)
+ LOAD_STRING_ARG0(mutex_assert_owned_str)
+ jmp 4f
+3:
+ ALIGN_STACK()
+ LOAD_PTR_ARG1(%rdx)
+ LOAD_STRING_ARG0(mutex_assert_not_owned_str)
+4:
+ CALL_PANIC()
-ml_retry:
- movl B_PC,%ecx
-ml_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp ml_get_hw /* try again */
-1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne ml_get_hw /* branch on failure to retry */
+lck_mtx_destroyed:
+ ALIGN_STACK()
+ LOAD_PTR_ARG1(%rdx)
+ LOAD_STRING_ARG0(mutex_interlock_destroyed_str)
+ CALL_PANIC()
+
- movl M_LOCKED,%ecx /* get lock owner */
- testl %ecx,%ecx /* is the mutex locked? */
- jne ml_fail /* yes, we lose */
- movl %gs:CPU_ACTIVE_THREAD,%ecx
- movl %ecx,M_LOCKED
+.data
+mutex_assert_not_owned_str:
+ .asciz "mutex (%p) not owned\n"
+mutex_assert_owned_str:
+ .asciz "mutex (%p) owned\n"
+mutex_interlock_destroyed_str:
+ .asciz "trying to interlock destroyed mutex (%p)"
+.text
-#if MACH_LDEBUG
- movl %ecx,M_THREAD
- movl B_PC,%ecx
- movl %ecx,M_PC
-#endif
- pushl %edx /* save mutex address */
- pushl %edx
- call EXT(lck_mtx_lock_acquire)
- addl $4,%esp
- popl %edx /* restore mutex address */
- xorl %eax,%eax
- movl %eax,M_ILK
+/*
+ * lck_mtx_lock()
+ * lck_mtx_try_lock()
+ * lck_mtx_unlock()
+ * lck_mtx_lock_spin()
+ * lck_mtx_lock_spin_always()
+ * lck_mtx_try_lock_spin()
+ * lck_mtx_try_lock_spin_always()
+ * lck_mtx_convert_spin()
+ */
+NONLEAF_ENTRY(lck_mtx_lock_spin_always)
+ mov %rdi, %rdx /* fetch lock pointer */
+ jmp Llmls_avoid_check
+
+NONLEAF_ENTRY(lck_mtx_lock_spin)
+ mov %rdi, %rdx /* fetch lock pointer */
- popf /* restore interrupt state */
+ CHECK_PREEMPTION_LEVEL()
+Llmls_avoid_check:
+ mov M_STATE(%rdx), %ecx
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* is the interlock or mutex held */
+ jnz Llmls_slow
+Llmls_try: /* no - can't be INDIRECT, DESTROYED or locked */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_SPIN_MSK), %ecx
+
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llmls_busy_disabled
- NONLEAF_RET
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of interlock */
+#if MACH_LDEBUG
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
-ml_fail:
-ml_block:
- CHECK_MYLOCK(M_THREAD)
- pushl M_LOCKED
- pushl %edx /* push mutex address */
- call EXT(lck_mtx_lock_wait) /* wait for the lock */
- addl $8,%esp
- movl B_ARG0,%edx /* refetch mutex address */
- jmp ml_retry /* and try again */
+ /* return with the interlock held and preemption disabled */
+ leave
+#if CONFIG_DTRACE
+ LOCKSTAT_LABEL(_lck_mtx_lock_spin_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_LOCK_SPIN_ACQUIRE, %rdx)
+#endif
+ ret
-NONLEAF_ENTRY2(mutex_try,_mutex_try)
+Llmls_slow:
+ test $M_ILOCKED_MSK, %ecx /* is the interlock held */
+ jz Llml_contended /* no, must have been the mutex */
- movl B_ARG0,%edx /* fetch lock pointer */
+ cmp $(MUTEX_DESTROYED), %ecx /* check to see if its marked destroyed */
+ je lck_mtx_destroyed
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex */
+ jne Llmls_loop /* no... must be interlocked */
- CHECK_MUTEX_TYPE()
- CHECK_NO_SIMPLELOCKS()
+ LMTX_ENTER_EXTENDED
- movl B_PC,%ecx
+ mov M_STATE(%rdx), %ecx
+ test $(M_SPIN_MSK), %ecx
+ jz Llmls_loop1
- pushf /* save interrupt state */
- cli /* disable interrupts */
+ LMTX_UPDATE_MISS /* M_SPIN_MSK was set, so M_ILOCKED_MSK must also be present */
+Llmls_loop:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+Llmls_loop1:
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
+ jz Llmls_try
+ test $(M_MLOCKED_MSK), %ecx
+ jnz Llml_contended /* mutex owned by someone else, go contend for it */
+ jmp Llmls_loop
-mt_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp mt_get_hw /* try again */
-1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne mt_get_hw /* branch on failure to retry */
+Llmls_busy_disabled:
+ PREEMPTION_ENABLE
+ jmp Llmls_loop
- movl M_LOCKED,%ecx /* get lock owner */
- testl %ecx,%ecx /* is the mutex locked? */
- jne mt_fail /* yes, we lose */
- movl %gs:CPU_ACTIVE_THREAD,%ecx
- movl %ecx,M_LOCKED
-#if MACH_LDEBUG
- movl %ecx,M_THREAD
- movl B_PC,%ecx
- movl %ecx,M_PC
-#endif
+
+NONLEAF_ENTRY(lck_mtx_lock)
+ mov %rdi, %rdx /* fetch lock pointer */
- pushl %edx /* save mutex address */
- pushl %edx
- call EXT(lck_mtx_lock_acquire)
- addl $4,%esp
- popl %edx /* restore mutex address */
+ CHECK_PREEMPTION_LEVEL()
- xorl %eax,%eax
- movl %eax,M_ILK
+ mov M_STATE(%rdx), %ecx
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* is the interlock or mutex held */
+ jnz Llml_slow
+Llml_try: /* no - can't be INDIRECT, DESTROYED or locked */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
- popf /* restore interrupt state */
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llml_busy_disabled
- movl $1,%eax
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
+#if MACH_LDEBUG
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
- NONLEAF_RET
+ testl $(M_WAITERS_MSK), M_STATE(%rdx)
+ jz Llml_finish
-mt_fail:
- xorl %eax,%eax
- movl %eax,M_ILK
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
- popf /* restore interrupt state */
+Llml_finish:
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
+ PREEMPTION_ENABLE
+
+ cmp %rdx, %rdi /* is this an extended mutex */
+ jne 2f
- xorl %eax,%eax
+ leave
+#if CONFIG_DTRACE
+ LOCKSTAT_LABEL(_lck_mtx_lock_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_LOCK_ACQUIRE, %rdx)
+#endif
+ ret
+2:
+ leave
+#if CONFIG_DTRACE
+ LOCKSTAT_LABEL(_lck_mtx_lock_ext_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_EXT_LOCK_ACQUIRE, %rdx)
+#endif
+ ret
- NONLEAF_RET
+
+Llml_slow:
+ test $M_ILOCKED_MSK, %ecx /* is the interlock held */
+ jz Llml_contended /* no, must have been the mutex */
+
+ cmp $(MUTEX_DESTROYED), %ecx /* check to see if its marked destroyed */
+ je lck_mtx_destroyed
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne Llml_loop /* no... must be interlocked */
+
+ LMTX_ENTER_EXTENDED
+
+ mov M_STATE(%rdx), %ecx
+ test $(M_SPIN_MSK), %ecx
+ jz Llml_loop1
+
+ LMTX_UPDATE_MISS /* M_SPIN_MSK was set, so M_ILOCKED_MSK must also be present */
+Llml_loop:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+Llml_loop1:
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
+ jz Llml_try
+ test $(M_MLOCKED_MSK), %ecx
+ jnz Llml_contended /* mutex owned by someone else, go contend for it */
+ jmp Llml_loop
+
+Llml_busy_disabled:
+ PREEMPTION_ENABLE
+ jmp Llml_loop
-NONLEAF_ENTRY(mutex_unlock)
- movl B_ARG0,%edx /* fetch lock pointer */
+
+Llml_contended:
+ cmp %rdx, %rdi /* is this an extended mutex */
+ je 0f
+ LMTX_UPDATE_MISS
+0:
+ LMTX_CALLEXT1(lck_mtx_lock_spinwait_x86)
+
+ test %rax, %rax
+ jz Llml_acquired /* acquired mutex, interlock held and preemption disabled */
+
+ cmp $1, %rax /* check for direct wait status */
+ je 2f
+ cmp %rdx, %rdi /* is this an extended mutex */
+ je 2f
+ LMTX_UPDATE_DIRECT_WAIT
+2:
+ mov M_STATE(%rdx), %ecx
+ test $(M_ILOCKED_MSK), %ecx
+ jnz 6f
+
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK), %ecx /* try to take the interlock */
+
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 5f
- CHECK_MUTEX_TYPE()
- CHECK_THREAD(M_THREAD)
+ test $(M_MLOCKED_MSK), %ecx /* we've got the interlock and */
+ jnz 3f
+ or $(M_MLOCKED_MSK), %ecx /* the mutex is free... grab it directly */
+ mov %ecx, M_STATE(%rdx)
+
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
+#if MACH_LDEBUG
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
- movl B_PC,%ecx
+Llml_acquired:
+ testl $(M_WAITERS_MSK), M_STATE(%rdx)
+ jnz 1f
+ mov M_OWNER(%rdx), %rax
+ mov TH_WAS_PROMOTED_ON_WAKEUP(%rax), %eax
+ test %eax, %eax
+ jz Llml_finish
+1:
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
+ jmp Llml_finish
+
+3: /* interlock held, mutex busy */
+ cmp %rdx, %rdi /* is this an extended mutex */
+ je 4f
+ LMTX_UPDATE_WAIT
+4:
+ LMTX_CALLEXT1(lck_mtx_lock_wait_x86)
+ jmp Llml_contended
+5:
+ PREEMPTION_ENABLE
+6:
+ PAUSE
+ jmp 2b
+
- pushf /* save interrupt state */
- cli /* disable interrupts */
+NONLEAF_ENTRY(lck_mtx_try_lock_spin_always)
+ mov %rdi, %rdx /* fetch lock pointer */
+ jmp Llmts_avoid_check
-mu_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp mu_get_hw /* try again */
-1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne mu_get_hw /* branch on failure to retry */
+NONLEAF_ENTRY(lck_mtx_try_lock_spin)
+ mov %rdi, %rdx /* fetch lock pointer */
- cmpw $0,M_WAITERS /* are there any waiters? */
- jne mu_wakeup /* yes, more work to do */
+Llmts_avoid_check:
+ mov M_STATE(%rdx), %ecx
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* is the interlock or mutex held */
+ jnz Llmts_slow
+Llmts_try: /* no - can't be INDIRECT, DESTROYED or locked */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_SPIN_MSK), %rcx
-mu_doit:
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llmts_busy_disabled
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
#if MACH_LDEBUG
- movl $0,M_THREAD /* disown thread */
-#endif
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
- xorl %ecx,%ecx
- movl %ecx,M_LOCKED /* unlock the mutex */
+ leave
- movl %ecx,M_ILK
+#if CONFIG_DTRACE
+ mov $1, %rax /* return success */
+ LOCKSTAT_LABEL(_lck_mtx_try_lock_spin_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_TRY_SPIN_LOCK_ACQUIRE, %rdx)
+#endif
+ mov $1, %rax /* return success */
+ ret
- popf /* restore interrupt state */
+Llmts_slow:
+ test $(M_ILOCKED_MSK), %ecx /* is the interlock held */
+ jz Llmts_fail /* no, must be held as a mutex */
+
+ cmp $(MUTEX_DESTROYED), %ecx /* check to see if its marked destroyed */
+ je lck_mtx_destroyed
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne Llmts_loop1
+
+ LMTX_ENTER_EXTENDED
+Llmts_loop:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+Llmts_loop1:
+ test $(M_MLOCKED_MSK | M_SPIN_MSK), %ecx
+ jnz Llmts_fail
+ test $(M_ILOCKED_MSK), %ecx
+ jz Llmts_try
+ jmp Llmts_loop
+
+Llmts_busy_disabled:
+ PREEMPTION_ENABLE
+ jmp Llmts_loop
- NONLEAF_RET
-mu_wakeup:
- pushl M_LOCKED
- pushl %edx /* push mutex address */
- call EXT(lck_mtx_unlock_wakeup)/* yes, wake a thread */
- addl $8,%esp
- movl B_ARG0,%edx /* restore lock pointer */
- jmp mu_doit
+
+NONLEAF_ENTRY(lck_mtx_try_lock)
+ mov %rdi, %rdx /* fetch lock pointer */
+
+ mov M_STATE(%rdx), %ecx
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* is the interlock or mutex held */
+ jnz Llmt_slow
+Llmt_try: /* no - can't be INDIRECT, DESTROYED or locked */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
+
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llmt_busy_disabled
-/*
- * lck_mtx_lock()
- * lck_mtx_try_lock()
- * lck_mutex_unlock()
- *
- * These are variants of mutex_lock(), mutex_try() and mutex_unlock() without
- * DEBUG checks (which require fields not present in lck_mtx_t's).
- */
-NONLEAF_ENTRY(lck_mtx_lock)
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
+#if MACH_LDEBUG
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
- movl B_ARG0,%edx /* fetch lock pointer */
- cmpl $(MUTEX_IND),M_ITAG /* is this indirect? */
- cmove M_PTR,%edx /* yes - take indirection */
+ test $(M_WAITERS_MSK), %ecx
+ jz 0f
- CHECK_NO_SIMPLELOCKS()
- CHECK_PREEMPTION_LEVEL()
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
+0:
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
+ PREEMPTION_ENABLE
- pushf /* save interrupt state */
- cli /* disable interrupts */
+ leave
+#if CONFIG_DTRACE
+ mov $1, %rax /* return success */
+ /* Dtrace probe: LS_LCK_MTX_TRY_LOCK_ACQUIRE */
+ LOCKSTAT_LABEL(_lck_mtx_try_lock_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx from above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_TRY_LOCK_ACQUIRE, %rdx)
+#endif
+ mov $1, %rax /* return success */
+ ret
-lml_retry:
- movl B_PC,%ecx
+Llmt_slow:
+ test $(M_ILOCKED_MSK), %ecx /* is the interlock held */
+ jz Llmt_fail /* no, must be held as a mutex */
+
+ cmp $(MUTEX_DESTROYED), %ecx /* check to see if its marked destroyed */
+ je lck_mtx_destroyed
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne Llmt_loop
+
+ LMTX_ENTER_EXTENDED
+Llmt_loop:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+Llmt_loop1:
+ test $(M_MLOCKED_MSK | M_SPIN_MSK), %ecx
+ jnz Llmt_fail
+ test $(M_ILOCKED_MSK), %ecx
+ jz Llmt_try
+ jmp Llmt_loop
+
+Llmt_busy_disabled:
+ PREEMPTION_ENABLE
+ jmp Llmt_loop
+
+
+Llmt_fail:
+Llmts_fail:
+ cmp %rdx, %rdi /* is this an extended mutex */
+ je 0f
+ LMTX_UPDATE_MISS
+0:
+ xor %rax, %rax
+ NONLEAF_RET
-lml_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp lml_get_hw /* try again */
-1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne lml_get_hw /* branch on failure to retry */
- movl M_LOCKED,%ecx /* get lock owner */
- testl %ecx,%ecx /* is the mutex locked? */
- jne lml_fail /* yes, we lose */
- movl %gs:CPU_ACTIVE_THREAD,%ecx
- movl %ecx,M_LOCKED
- pushl %edx /* save mutex address */
- pushl %edx
- call EXT(lck_mtx_lock_acquire)
- addl $4,%esp
- popl %edx /* restore mutex address */
+NONLEAF_ENTRY(lck_mtx_convert_spin)
+ mov %rdi, %rdx /* fetch lock pointer */
- xorl %eax,%eax
- movl %eax,M_ILK
+ mov M_STATE(%rdx), %ecx
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne 0f
+ mov M_PTR(%rdx), %rdx /* If so, take indirection */
+ mov M_STATE(%rdx), %ecx
+0:
+ test $(M_MLOCKED_MSK), %ecx /* already owned as a mutex, just return */
+ jnz 2f
+ test $(M_WAITERS_MSK), %ecx /* are there any waiters? */
+ jz 1f
- popf /* restore interrupt state */
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
+ mov M_STATE(%rdx), %ecx
+1:
+ and $(~(M_ILOCKED_MSK | M_SPIN_MSK)), %ecx /* convert from spin version to mutex */
+ or $(M_MLOCKED_MSK), %ecx
+ mov %ecx, M_STATE(%rdx) /* since I own the interlock, I don't need an atomic update */
+ PREEMPTION_ENABLE
+2:
NONLEAF_RET
-lml_fail:
- CHECK_MYLOCK(M_THREAD)
- pushl %edx /* save mutex address */
- pushl M_LOCKED
- pushl %edx /* push mutex address */
- call EXT(lck_mtx_lock_wait) /* wait for the lock */
- addl $8,%esp
- popl %edx /* restore mutex address */
- jmp lml_retry /* and try again */
-
-NONLEAF_ENTRY(lck_mtx_try_lock)
-
- movl B_ARG0,%edx /* fetch lock pointer */
- cmpl $(MUTEX_IND),M_ITAG /* is this indirect? */
- cmove M_PTR,%edx /* yes - take indirection */
+
- CHECK_NO_SIMPLELOCKS()
- CHECK_PREEMPTION_LEVEL()
+NONLEAF_ENTRY(lck_mtx_unlock)
+ mov %rdi, %rdx /* fetch lock pointer */
+Llmu_entry:
+ mov M_STATE(%rdx), %ecx
+Llmu_prim:
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ je Llmu_ext
+
+Llmu_chktype:
+ test $(M_MLOCKED_MSK), %ecx /* check for full mutex */
+ jz Llmu_unlock
+Llmu_mutex:
+ test $(M_ILOCKED_MSK), %rcx /* have to wait for interlock to clear */
+ jnz Llmu_busy
+
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ and $(~M_MLOCKED_MSK), %ecx /* drop mutex */
+ or $(M_ILOCKED_MSK), %ecx /* pick up interlock */
+
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llmu_busy_disabled /* branch on failure to spin loop */
- movl B_PC,%ecx
+Llmu_unlock:
+ xor %rax, %rax
+ mov %rax, M_OWNER(%rdx)
+ mov %rcx, %rax /* keep original state in %ecx for later evaluation */
+ and $(~(M_ILOCKED_MSK | M_SPIN_MSK | M_PROMOTED_MSK)), %rax
- pushf /* save interrupt state */
- cli /* disable interrupts */
+ test $(M_WAITERS_MSK), %eax
+ jz 2f
+ dec %eax /* decrement waiter count */
+2:
+ mov %eax, M_STATE(%rdx) /* since I own the interlock, I don't need an atomic update */
-lmt_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp lmt_get_hw /* try again */
+#if MACH_LDEBUG
+ /* perform lock statistics after drop to prevent delay */
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ test %rax, %rax
+ jz 1f
+ decl TH_MUTEX_COUNT(%rax) /* lock statistic */
1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne lmt_get_hw /* branch on failure to retry */
+#endif /* MACH_LDEBUG */
- movl M_LOCKED,%ecx /* get lock owner */
- testl %ecx,%ecx /* is the mutex locked? */
- jne lmt_fail /* yes, we lose */
- movl %gs:CPU_ACTIVE_THREAD,%ecx
- movl %ecx,M_LOCKED
+ test $(M_PROMOTED_MSK | M_WAITERS_MSK), %ecx
+ jz 3f
- pushl %edx /* save mutex address */
- pushl %edx
- call EXT(lck_mtx_lock_acquire)
- addl $4,%esp
- popl %edx /* restore mutex address */
+ LMTX_CALLEXT2(lck_mtx_unlock_wakeup_x86, %rcx)
+3:
+ PREEMPTION_ENABLE
- xorl %eax,%eax
- movl %eax,M_ILK
+ cmp %rdx, %rdi
+ jne 4f
- popf /* restore interrupt state */
+ leave
+#if CONFIG_DTRACE
+ /* Dtrace: LS_LCK_MTX_UNLOCK_RELEASE */
+ LOCKSTAT_LABEL(_lck_mtx_unlock_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx from above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_UNLOCK_RELEASE, %rdx)
+#endif
+ ret
+4:
+ leave
+#if CONFIG_DTRACE
+ /* Dtrace: LS_LCK_MTX_EXT_UNLOCK_RELEASE */
+ LOCKSTAT_LABEL(_lck_mtx_ext_unlock_lockstat_patch_point)
+ ret
+ /* inherit lock pointer in %rdx from above */
+ LOCKSTAT_RECORD(LS_LCK_MTX_EXT_UNLOCK_RELEASE, %rdx)
+#endif
+ ret
- movl $1,%eax /* return success */
- NONLEAF_RET
-lmt_fail:
- xorl %eax,%eax
- movl %eax,M_ILK
+Llmu_busy_disabled:
+ PREEMPTION_ENABLE
+Llmu_busy:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+ jmp Llmu_mutex
- popf /* restore interrupt state */
+Llmu_ext:
+ mov M_PTR(%rdx), %rdx
+ mov M_OWNER(%rdx), %rax
+ mov %gs:CPU_ACTIVE_THREAD, %rcx
+ CHECK_UNLOCK(%rcx, %rax)
+ mov M_STATE(%rdx), %ecx
+ jmp Llmu_chktype
- xorl %eax,%eax /* return failure */
- NONLEAF_RET
-NONLEAF_ENTRY(lck_mtx_unlock)
+
+LEAF_ENTRY(lck_mtx_ilk_try_lock)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
- movl B_ARG0,%edx /* fetch lock pointer */
- cmpl $(MUTEX_IND),M_ITAG /* is this indirect? */
- cmove M_PTR,%edx /* yes - take indirection */
+ mov M_STATE(%rdx), %ecx
- movl B_PC,%ecx
+ test $(M_ILOCKED_MSK), %ecx /* can't have the interlock yet */
+ jnz 3f
- pushf /* save interrupt state */
- cli /* disable interrupts */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK), %ecx
-lmu_get_hw:
- movl M_ILK,%eax /* read interlock */
- testl %eax,%eax /* unlocked? */
- je 1f /* yes - attempt to lock it */
- PAUSE /* no - pause */
- jmp lmu_get_hw /* try again */
-1:
- lock; cmpxchgl %ecx,M_ILK /* atomic compare and exchange */
- jne lmu_get_hw /* branch on failure to retry */
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 2f /* return failure after re-enabling preemption */
- cmpw $0,M_WAITERS /* are there any waiters? */
- jne lmu_wakeup /* yes, more work to do */
+ mov $1, %rax /* return success with preemption disabled */
+ LEAF_RET
+2:
+ PREEMPTION_ENABLE /* need to re-enable preemption */
+3:
+ xor %rax, %rax /* return failure */
+ LEAF_RET
+
-lmu_doit:
- xorl %ecx,%ecx
- movl %ecx,M_LOCKED /* unlock the mutex */
+LEAF_ENTRY(lck_mtx_ilk_unlock)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
- movl %ecx,M_ILK
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
- popf /* restore interrupt state */
+ PREEMPTION_ENABLE /* need to re-enable preemption */
- NONLEAF_RET
+ LEAF_RET
-lmu_wakeup:
- pushl %edx /* save mutex address */
- pushl M_LOCKED
- pushl %edx /* push mutex address */
- call EXT(lck_mtx_unlock_wakeup)/* yes, wake a thread */
- addl $8,%esp
- popl %edx /* restore mutex pointer */
- jmp lmu_doit
+
+LEAF_ENTRY(lck_mtx_lock_grab_mutex)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
-LEAF_ENTRY(lck_mtx_ilk_unlock)
- movl L_ARG0,%edx /* no indirection here */
+ mov M_STATE(%rdx), %ecx
- xorl %eax,%eax
- movl %eax,M_ILK
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* can't have the mutex yet */
+ jnz 3f
- LEAF_RET
-
-LEAF_ENTRY(_disable_preemption)
-#if MACH_RT
- _DISABLE_PREEMPTION
-#endif /* MACH_RT */
- LEAF_RET
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
-LEAF_ENTRY(_enable_preemption)
-#if MACH_RT
-#if MACH_ASSERT
- cmpl $0,%gs:CPU_PREEMPTION_LEVEL
- jg 1f
- pushl %gs:CPU_PREEMPTION_LEVEL
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_enable_preemption: preemption_level(%d) < 0!"
- .text
-1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION
-#endif /* MACH_RT */
- LEAF_RET
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 2f /* branch on failure to spin loop */
-LEAF_ENTRY(_enable_preemption_no_check)
-#if MACH_RT
-#if MACH_ASSERT
- cmpl $0,%gs:CPU_PREEMPTION_LEVEL
- jg 1f
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_enable_preemption_no_check: preemption_level <= 0!"
- .text
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
+#if MACH_LDEBUG
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION_NO_CHECK
-#endif /* MACH_RT */
- LEAF_RET
-
-
-LEAF_ENTRY(_mp_disable_preemption)
-#if MACH_RT
- _DISABLE_PREEMPTION
-#endif /* MACH_RT */
- LEAF_RET
+#endif /* MACH_LDEBUG */
-LEAF_ENTRY(_mp_enable_preemption)
-#if MACH_RT
-#if MACH_ASSERT
- cmpl $0,%gs:CPU_PREEMPTION_LEVEL
- jg 1f
- pushl %gs:CPU_PREEMPTION_LEVEL
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_mp_enable_preemption: preemption_level (%d) <= 0!"
- .text
-1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION
-#endif /* MACH_RT */
+ mov $1, %rax /* return success */
LEAF_RET
-
-LEAF_ENTRY(_mp_enable_preemption_no_check)
-#if MACH_RT
-#if MACH_ASSERT
- cmpl $0,%gs:CPU_PREEMPTION_LEVEL
- jg 1f
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_mp_enable_preemption_no_check: preemption_level <= 0!"
- .text
-1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION_NO_CHECK
-#endif /* MACH_RT */
+2:
+ PREEMPTION_ENABLE
+3:
+ xor %rax, %rax /* return failure */
LEAF_RET
-
-LEAF_ENTRY(i_bit_set)
- movl L_ARG0,%edx
- movl L_ARG1,%eax
- lock
- bts %dl,(%eax)
- LEAF_RET
-LEAF_ENTRY(i_bit_clear)
- movl L_ARG0,%edx
- movl L_ARG1,%eax
- lock
- btr %dl,(%eax)
- LEAF_RET
-LEAF_ENTRY(bit_lock)
- movl L_ARG0,%ecx
- movl L_ARG1,%eax
+LEAF_ENTRY(lck_mtx_lock_mark_destroyed)
+ mov %rdi, %rdx
1:
+ mov M_STATE(%rdx), %ecx
+ cmp $(MUTEX_IND), %ecx /* Is this an indirect mutex? */
+ jne 2f
+
+ movl $(MUTEX_DESTROYED), M_STATE(%rdx) /* convert to destroyed state */
+ jmp 3f
+2:
+ test $(M_ILOCKED_MSK), %rcx /* have to wait for interlock to clear */
+ jnz 5f
+
+ PREEMPTION_DISABLE
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK), %ecx
lock
- bts %ecx,(%eax)
- jb 1b
- LEAF_RET
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 4f /* branch on failure to spin loop */
+ movl $(MUTEX_DESTROYED), M_STATE(%rdx) /* convert to destroyed state */
+ PREEMPTION_ENABLE
+3:
+ LEAF_RET /* return with M_ILOCKED set */
+4:
+ PREEMPTION_ENABLE
+5:
+ PAUSE
+ jmp 1b
+
+LEAF_ENTRY(preemption_underflow_panic)
+ FRAME
+ incl %gs:CPU_PREEMPTION_LEVEL
+ ALIGN_STACK()
+ LOAD_STRING_ARG0(16f)
+ CALL_PANIC()
+ hlt
+ .data
+16: String "Preemption level underflow, possible cause unlocking an unlocked mutex or spinlock"
+ .text
-LEAF_ENTRY(bit_lock_try)
- movl L_ARG0,%ecx
- movl L_ARG1,%eax
- lock
- bts %ecx,(%eax)
- jb bit_lock_failed
- LEAF_RET /* %eax better not be null ! */
-bit_lock_failed:
- xorl %eax,%eax
- LEAF_RET
-LEAF_ENTRY(bit_unlock)
- movl L_ARG0,%ecx
- movl L_ARG1,%eax
- lock
- btr %ecx,(%eax)
- LEAF_RET
projects / apple / xnu.git / blobdiff