/*
- * 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@
*
- * 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,
- * 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@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
* the terms and conditions for use and redistribution.
*/
-#include <cpus.h>
-#include <mach_rt.h>
-#include <platforms.h>
#include <mach_ldebug.h>
#include <i386/asm.h>
-#include <assym.s>
-#include <kern/etap_options.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 ((MACH_LDEBUG || ETAP_LOCK_TRACE) && MACH_KDB)
+#include <i386/pal_lock_asm.h>
-#if BUILD_STACK_FRAMES
+#define LEAF_ENTRY(name) \
+ Entry(name)
-#define L_PC 4(%ebp)
-#define L_ARG0 8(%ebp)
-#define L_ARG1 12(%ebp)
+#define LEAF_ENTRY2(n1,n2) \
+ Entry(n1); \
+ Entry(n2)
-#define SWT_HI -4(%ebp)
-#define SWT_LO -8(%ebp)
-#define MISSED -12(%ebp)
+#define LEAF_RET \
+ ret
-#else /* BUILD_STACK_FRAMES */
+/* Non-leaf routines always have a stack frame: */
-#undef FRAME
-#undef EMARF
-#define FRAME
-#define EMARF
-#define L_PC (%esp)
-#define L_ARG0 4(%esp)
-#define L_ARG1 8(%esp)
+#define NONLEAF_ENTRY(name) \
+ Entry(name); \
+ FRAME
-#endif /* BUILD_STACK_FRAMES */
+#define NONLEAF_ENTRY2(n1,n2) \
+ Entry(n1); \
+ Entry(n2); \
+ FRAME
+#define NONLEAF_RET \
+ EMARF; \
+ ret
-#define M_ILK (%edx)
-#define M_LOCKED 1(%edx)
-#define M_WAITERS 2(%edx)
-#if MACH_LDEBUG
-#define M_TYPE 4(%edx)
-#define M_PC 8(%edx)
-#define M_THREAD 12(%edx)
-#endif /* MACH_LDEBUG */
-#include <i386/AT386/mp/mp.h>
-#if (NCPUS > 1)
-#define CX(addr,reg) addr(,reg,4)
-#else
-#define CPU_NUMBER(reg)
-#define CX(addr,reg) addr
-#endif /* (NCPUS > 1) */
+/* 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) ;
+
+#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 4(%edx)
-#define S_PC 8(%edx)
-#define S_THREAD 12(%edx)
-#define S_DURATIONH 16(%edx)
-#define S_DURATIONL 20(%edx)
/*
* Checks for expected lock types and calls "panic" on
* type simplelock and vice versa.
*/
#define CHECK_MUTEX_TYPE() \
- cmpl $MUTEX_TAG, M_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 $SIMPLE_LOCK_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 0 /*MACH_RT - 11/12/99 - lion@apple.com disable check for now*/
#define CHECK_PREEMPTION_LEVEL() \
- movl $CPD_PREEMPTION_LEVEL,%eax ; \
- cmpl $0,%gs:(%eax) ; \
+ 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() \
- movl $CPD_SIMPLE_LOCK_COUNT,%eax ; \
- cmpl $0,%gs:(%eax) ; \
- 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 $CPD_ACTIVE_THREAD,%eax ; \
- movl %gs:(%eax),%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 $CPD_ACTIVE_THREAD,%eax ; \
- movl %gs:(%eax),%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.
*/
-ENTRY(hw_lock_init)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
- xorl %eax,%eax
- movb %al,0(%edx) /* clear the lock */
- EMARF
- ret
+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.
*/
-ENTRY(hw_lock_lock)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
-1: DISABLE_PREEMPTION(%eax)
- movb $1,%cl
- xchgb 0(%edx),%cl /* try to acquire the HW lock */
- testb %cl,%cl /* success? */
+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; cmpxchg %cl,(%rdi) /* attempt atomic compare exchange */
jne 3f
-
- EMARF /* if yes, then nothing left to do */
- ret
-
-3: ENABLE_PREEMPTION(%eax) /* no reason we can't be preemptable now */
-
- movb $1,%cl
-2: testb %cl,0(%edx) /* spin checking lock value in cache */
- jne 2b /* non-zero means locked, keep spinning */
- jmp 1b /* zero means unlocked, try to grab it */
+ LEAF_RET /* if yes, then nothing left to do */
+3:
+ PAUSE /* pause for hyper-threading */
+ jmp 1b /* try again */
/*
- * void hw_lock_unlock(hw_lock_t)
+ * void hw_lock_byte_unlock(uint8_t *lock_byte)
*
- * Unconditionally release lock.
- * MACH_RT: release preemption level.
+ * Unconditionally release byte sized lock operand,
+ * release preemption level.
*/
-ENTRY(hw_lock_unlock)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
- xorl %eax,%eax
- xchgb 0(%edx),%al /* clear the lock... a mov instruction */
- /* ...might be cheaper and less paranoid */
- ENABLE_PREEMPTION(%eax)
- EMARF
- ret
+LEAF_ENTRY(hw_lock_byte_unlock)
+ movb $0, (%rdi) /* Clear the lock byte */
+ PREEMPTION_ENABLE
+ LEAF_RET
+
/*
- * unsigned int hw_lock_try(hw_lock_t)
- * MACH_RT: returns with preemption disabled on success.
+ * 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).
+ *
+ *
+ * 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
*/
-ENTRY(hw_lock_try)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
+#undef LOG_FIRST_MISS_ALONE
- DISABLE_PREEMPTION(%eax)
- movb $1,%cl
- xchgb 0(%edx),%cl /* try to acquire the HW lock */
- testb %cl,%cl /* success? */
- jne 1f /* if yes, let the caller know */
+/*
+ * This preprocessor define controls whether the R-M-W update of the
+ * per-group statistics elements are atomic (LOCK-prefixed)
+ * Enabled by default.
+ */
+#define ATOMIC_STAT_UPDATES 1
- movl $1,%eax /* success */
- EMARF
- ret
+#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(%eax) /* failure: release preemption... */
- xorl %eax,%eax /* ...and return failure */
- EMARF
- 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.
*/
-ENTRY(hw_lock_held)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
- movb $1,%cl
- testb %cl,0(%edx) /* check lock value */
- jne 1f /* non-zero means locked */
- xorl %eax,%eax /* tell caller: lock wasn't locked */
- EMARF
- ret
+#define M_OWNER MUTEX_OWNER
+#define M_PTR MUTEX_PTR
+#define M_STATE MUTEX_STATE
+
-1: movl $1,%eax /* tell caller: lock was locked */
- EMARF
- ret
+#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 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
-#if 0
+/*
+ * 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)
-ENTRY(_usimple_lock_init)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
- xorl %eax,%eax
- movb %al,USL_INTERLOCK(%edx) /* unlock the HW lock */
- EMARF
- ret
+
+#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
-ENTRY(_simple_lock)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
+/*
+ * 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.
+ *
+ */
- CHECK_SIMPLE_LOCK_TYPE()
+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()
+
+
+lck_mtx_destroyed:
+ ALIGN_STACK()
+ LOAD_PTR_ARG1(%rdx)
+ LOAD_STRING_ARG0(mutex_interlock_destroyed_str)
+ CALL_PANIC()
+
- DISABLE_PREEMPTION(%eax)
+.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
-sl_get_hw:
- movb $1,%cl
- xchgb USL_INTERLOCK(%edx),%cl /* try to acquire the HW lock */
- testb %cl,%cl /* did we succeed? */
-#if MACH_LDEBUG
- je 5f
- CHECK_MYLOCK(S_THREAD)
- jmp sl_get_hw
-5:
-#else /* MACH_LDEBUG */
- jne sl_get_hw /* no, try again */
-#endif /* MACH_LDEBUG */
+/*
+ * 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 */
+
+ 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
+
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of interlock */
#if MACH_LDEBUG
- movl L_PC,%ecx
- movl %ecx,S_PC
- movl $CPD_ACTIVE_THREAD,%eax
- movl %gs:(%eax),%ecx
- movl %ecx,S_THREAD
- incl CX(EXT(simple_lock_count),%eax)
-#if 0
- METER_SIMPLE_LOCK_LOCK(%edx)
-#endif
-#if NCPUS == 1
- pushf
- pushl %edx
- cli
- call EXT(lock_stack_push)
- popl %edx
- popfl
-#endif /* NCPUS == 1 */
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
#endif /* MACH_LDEBUG */
- EMARF
+ /* 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
-ENTRY(_simple_lock_try)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
+Llmls_slow:
+ test $M_ILOCKED_MSK, %ecx /* is the interlock held */
+ jz Llml_contended /* no, must have been the mutex */
- CHECK_SIMPLE_LOCK_TYPE()
+ 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 */
- DISABLE_PREEMPTION(%eax)
+ LMTX_ENTER_EXTENDED
- movb $1,%cl
- xchgb USL_INTERLOCK(%edx),%cl /* try to acquire the HW lock */
- testb %cl,%cl /* did we succeed? */
- jne 1f /* no, return failure */
+ mov M_STATE(%rdx), %ecx
+ test $(M_SPIN_MSK), %ecx
+ jz Llmls_loop1
-#if MACH_LDEBUG
- movl L_PC,%ecx
- movl %ecx,S_PC
- movl $CPD_ACTIVE_THREAD,%eax
- movl %gs:(%eax),%ecx
- movl %ecx,S_THREAD
- incl CX(EXT(simple_lock_count),%eax)
-#if 0
- METER_SIMPLE_LOCK_LOCK(%edx)
-#endif
-#if NCPUS == 1
- pushf
- pushl %edx
- cli
- call EXT(lock_stack_push)
- popl %edx
- popfl
-#endif /* NCPUS == 1 */
-#endif /* MACH_LDEBUG */
+ 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
- movl $1,%eax /* return success */
+Llmls_busy_disabled:
+ PREEMPTION_ENABLE
+ jmp Llmls_loop
- EMARF
- ret
-1:
- ENABLE_PREEMPTION(%eax)
-
- xorl %eax,%eax /* and return failure */
+
+NONLEAF_ENTRY(lck_mtx_lock)
+ mov %rdi, %rdx /* fetch lock pointer */
- EMARF
- ret
+ CHECK_PREEMPTION_LEVEL()
-ENTRY(_simple_unlock)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
+ 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
- CHECK_SIMPLE_LOCK_TYPE()
- CHECK_THREAD(S_THREAD)
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne Llml_busy_disabled
+ mov %gs:CPU_ACTIVE_THREAD, %rax
+ mov %rax, M_OWNER(%rdx) /* record owner of mutex */
#if MACH_LDEBUG
- xorl %eax,%eax
- movl %eax,S_THREAD /* disown thread */
- MP_DISABLE_PREEMPTION(%eax)
- CPU_NUMBER(%eax)
- decl CX(EXT(simple_lock_count),%eax)
- MP_ENABLE_PREEMPTION(%eax)
-#if 0
- METER_SIMPLE_LOCK_UNLOCK(%edx)
-#endif
-#if NCPUS == 1
- pushf
- pushl %edx
- cli
- call EXT(lock_stack_pop)
- popl %edx
- popfl
-#endif /* NCPUS == 1 */
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
#endif /* MACH_LDEBUG */
- xorb %cl,%cl
- xchgb USL_INTERLOCK(%edx),%cl /* unlock the HW lock */
-
- ENABLE_PREEMPTION(%eax)
-
- EMARF
- ret
-
-#endif /* 0 */
+ testl $(M_WAITERS_MSK), M_STATE(%rdx)
+ jz Llml_finish
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
-ENTRY(mutex_init)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
- xorl %eax,%eax
- movb %al,M_ILK /* clear interlock */
- movb %al,M_LOCKED /* clear locked flag */
- movw %ax,M_WAITERS /* init waiter count */
+Llml_finish:
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
+ PREEMPTION_ENABLE
+
+ cmp %rdx, %rdi /* is this an extended mutex */
+ jne 2f
-#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 */
+ 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
-#if ETAP_LOCK_TRACE
- movl L_ARG1,%ecx /* fetch event type */
- pushl %ecx /* push event type */
- pushl %edx /* push mutex address */
- call EXT(etap_mutex_init) /* init ETAP data */
- addl $8,%esp
-#endif /* ETAP_LOCK_TRACE */
-
- EMARF
ret
-ENTRY(_mutex_lock)
- FRAME
+
+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
-#if ETAP_LOCK_TRACE
- subl $12,%esp /* make room for locals */
- movl $0,SWT_HI /* set wait time to zero (HI) */
- movl $0,SWT_LO /* set wait time to zero (LO) */
- movl $0,MISSED /* clear local miss marker */
-#endif /* ETAP_LOCK_TRACE */
+
+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
- movl L_ARG0,%edx /* fetch lock pointer */
+ 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 */
- CHECK_MUTEX_TYPE()
- CHECK_NO_SIMPLELOCKS()
- CHECK_PREEMPTION_LEVEL()
+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
+
-ml_retry:
- DISABLE_PREEMPTION(%eax)
+NONLEAF_ENTRY(lck_mtx_try_lock_spin_always)
+ mov %rdi, %rdx /* fetch lock pointer */
+ jmp Llmts_avoid_check
-ml_get_hw:
- movb $1,%cl
- xchgb %cl,M_ILK
- testb %cl,%cl /* did we succeed? */
- jne ml_get_hw /* no, try again */
+NONLEAF_ENTRY(lck_mtx_try_lock_spin)
+ mov %rdi, %rdx /* fetch lock pointer */
-/*
-/ Beware of a race between this code path and the inline ASM fast-path locking
-/ sequence which attempts to lock a mutex by directly setting the locked flag
-/
-*/
+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
- movb $1,%cl
- xchgb %cl,M_LOCKED /* try to set locked flag */
- testb %cl,%cl /* is the mutex locked? */
- jne ml_fail /* yes, we lose */
+ 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 L_PC,%ecx
- movl %ecx,M_PC
- movl $CPD_ACTIVE_THREAD,%eax
- movl %gs:(%eax),%ecx
- movl %ecx,M_THREAD
- testl %ecx,%ecx
- je 3f
- incl TH_MUTEX_COUNT(%ecx)
-3:
+ test %rax, %rax
+ jz 1f
+ incl TH_MUTEX_COUNT(%rax) /* lock statistic */
+1:
+#endif /* MACH_LDEBUG */
+
+ leave
+
+#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
- xorb %cl,%cl
- xchgb %cl,M_ILK
+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
- ENABLE_PREEMPTION(%eax)
-#if ETAP_LOCK_TRACE
- movl L_PC,%eax /* fetch pc */
- pushl SWT_LO /* push wait time (low) */
- pushl SWT_HI /* push wait time (high) */
- pushl %eax /* push pc */
- pushl %edx /* push mutex address */
- call EXT(etap_mutex_hold) /* collect hold timestamp */
- addl $16+12,%esp /* clean up stack, adjusting for locals */
-#endif /* ETAP_LOCK_TRACE */
+
+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
- EMARF
+ 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 */
+
+ test $(M_WAITERS_MSK), %ecx
+ jz 0f
+
+ LMTX_CALLEXT1(lck_mtx_lock_acquire_x86)
+0:
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
+ PREEMPTION_ENABLE
+
+ 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
-ml_fail:
-#if ETAP_LOCK_TRACE
- cmp $0,MISSED /* did we already take a wait timestamp? */
- jne ml_block /* yup. carry-on */
- pushl %edx /* push mutex address */
- call EXT(etap_mutex_miss) /* get wait timestamp */
- movl %eax,SWT_HI /* set wait time (high word) */
- movl %edx,SWT_LO /* set wait time (low word) */
- popl %edx /* clean up stack */
- movl $1,MISSED /* mark wait timestamp as taken */
-#endif /* ETAP_LOCK_TRACE */
-
-ml_block:
- CHECK_MYLOCK(M_THREAD)
- pushl %edx /* push mutex address */
- call EXT(mutex_lock_wait) /* wait for the lock */
- addl $4,%esp
- movl L_ARG0,%edx /* refetch lock pointer */
- jmp ml_retry /* and try again */
-
-ENTRY(_mutex_try)
- FRAME
+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
+
-#if ETAP_LOCK_TRACE
- subl $8,%esp /* make room for locals */
- movl $0,SWT_HI /* set wait time to zero (HI) */
- movl $0,SWT_LO /* set wait time to zero (LO) */
-#endif /* ETAP_LOCK_TRACE */
- movl L_ARG0,%edx /* fetch lock pointer */
+NONLEAF_ENTRY(lck_mtx_convert_spin)
+ mov %rdi, %rdx /* fetch lock pointer */
- CHECK_MUTEX_TYPE()
- CHECK_NO_SIMPLELOCKS()
+ 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
+
+ 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
- xorl %eax,%eax
- movb $1,%al /* locked value for mutex */
- xchgb %al,M_LOCKED /* swap locked values */
- xorb $1,%al /* generate return value */
+
-#if MACH_LDEBUG || ETAP_LOCK_TRACE
- testl %eax,%eax /* did we succeed? */
- je 2f /* no, skip */
-#endif
+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 */
+
+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
+
+ 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 */
#if MACH_LDEBUG
- movl L_PC,%ecx
- movl %ecx,M_PC
- movl $CPD_ACTIVE_THREAD,%ecx
- movl %gs:(%ecx),%ecx
- movl %ecx,M_THREAD
- testl %ecx,%ecx
- je 1f
- incl TH_MUTEX_COUNT(%ecx)
+ /* 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:
-#endif
+#endif /* MACH_LDEBUG */
-#if ETAP_LOCK_TRACE
- movl L_PC,%eax /* fetch pc */
- pushl SWT_LO /* push wait time (low) */
- pushl SWT_HI /* push wait time (high) */
- pushl %eax /* push pc */
- pushl %edx /* push mutex address */
- call EXT(etap_mutex_hold) /* get start hold timestamp */
- addl $16,%esp /* clean up stack, adjusting for locals */
- movl $1,%eax /* put back successful return value */
-#endif /* ETAP_LOCK_TRACE */
-
-#if MACH_LDEBUG || ETAP_LOCK_TRACE
-2:
-#if ETAP_LOCK_TRACE
- addl $8,%esp /* pop stack claimed on entry */
+ test $(M_PROMOTED_MSK | M_WAITERS_MSK), %ecx
+ jz 3f
+
+ LMTX_CALLEXT2(lck_mtx_unlock_wakeup_x86, %rcx)
+3:
+ PREEMPTION_ENABLE
+
+ cmp %rdx, %rdi
+ jne 4f
+
+ 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
-
- EMARF
ret
-ENTRY(mutex_unlock)
- FRAME
- movl L_ARG0,%edx /* fetch lock pointer */
-#if ETAP_LOCK_TRACE
- pushl %edx /* push mutex address */
- call EXT(etap_mutex_unlock) /* collect ETAP data */
- popl %edx /* restore mutex address */
-#endif /* ETAP_LOCK_TRACE */
+Llmu_busy_disabled:
+ PREEMPTION_ENABLE
+Llmu_busy:
+ PAUSE
+ mov M_STATE(%rdx), %ecx
+ jmp Llmu_mutex
- CHECK_MUTEX_TYPE()
- CHECK_THREAD(M_THREAD)
+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
- DISABLE_PREEMPTION(%eax)
-mu_get_hw:
- movb $1,%cl
- xchgb %cl,M_ILK
- testb %cl,%cl /* did we succeed? */
- jne mu_get_hw /* no, try again */
+
+LEAF_ENTRY(lck_mtx_ilk_try_lock)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
- cmpw $0,M_WAITERS /* are there any waiters? */
- jne mu_wakeup /* yes, more work to do */
+ mov M_STATE(%rdx), %ecx
-mu_doit:
-#if MACH_LDEBUG
- xorl %eax,%eax
- movl %eax,M_THREAD /* disown thread */
- movl $CPD_ACTIVE_THREAD,%eax
- movl %gs:(%eax),%ecx
- testl %ecx,%ecx
- je 0f
- decl TH_MUTEX_COUNT(%ecx)
-0:
-#endif
+ test $(M_ILOCKED_MSK), %ecx /* can't have the interlock yet */
+ jnz 3f
- xorb %cl,%cl
- xchgb %cl,M_LOCKED /* unlock the mutex */
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK), %ecx
- xorb %cl,%cl
- xchgb %cl,M_ILK
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 2f /* return failure after re-enabling preemption */
+
+ 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
+
- ENABLE_PREEMPTION(%eax)
+LEAF_ENTRY(lck_mtx_ilk_unlock)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
- EMARF
- ret
+ andl $(~M_ILOCKED_MSK), M_STATE(%rdx)
-mu_wakeup:
- pushl %edx /* push mutex address */
- call EXT(mutex_unlock_wakeup)/* yes, wake a thread */
- addl $4,%esp
- movl L_ARG0,%edx /* refetch lock pointer */
- jmp mu_doit
+ PREEMPTION_ENABLE /* need to re-enable preemption */
-ENTRY(interlock_unlock)
- FRAME
- movl L_ARG0,%edx
+ LEAF_RET
- xorb %cl,%cl
- xchgb %cl,M_ILK
+
+LEAF_ENTRY(lck_mtx_lock_grab_mutex)
+ mov %rdi, %rdx /* fetch lock pointer - no indirection here */
- ENABLE_PREEMPTION(%eax)
+ mov M_STATE(%rdx), %ecx
- EMARF
- ret
+ test $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx /* can't have the mutex yet */
+ jnz 3f
-
-ENTRY(_disable_preemption)
-#if MACH_RT
- _DISABLE_PREEMPTION(%eax)
-#endif /* MACH_RT */
- ret
+ mov %rcx, %rax /* eax contains snapshot for cmpxchgl */
+ or $(M_ILOCKED_MSK | M_MLOCKED_MSK), %ecx
-ENTRY(_enable_preemption)
-#if MACH_RT
-#if MACH_ASSERT
- movl $CPD_PREEMPTION_LEVEL,%eax
- cmpl $0,%gs:(%eax)
- jg 1f
- pushl %gs:(%eax)
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_enable_preemption: preemption_level(%d) < 0!"
- .text
-1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION(%eax)
-#endif /* MACH_RT */
- ret
+ PREEMPTION_DISABLE
+ lock
+ cmpxchg %ecx, M_STATE(%rdx) /* atomic compare and exchange */
+ jne 2f /* branch on failure to spin loop */
-ENTRY(_enable_preemption_no_check)
-#if MACH_RT
-#if MACH_ASSERT
- movl $CPD_PREEMPTION_LEVEL,%eax
- cmpl $0,%gs:(%eax)
- 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(%eax)
-#endif /* MACH_RT */
- ret
-
+#endif /* MACH_LDEBUG */
+
+ mov $1, %rax /* return success */
+ LEAF_RET
+2:
+ PREEMPTION_ENABLE
+3:
+ xor %rax, %rax /* return failure */
+ LEAF_RET
-ENTRY(_mp_disable_preemption)
-#if MACH_RT && NCPUS > 1
- _DISABLE_PREEMPTION(%eax)
-#endif /* MACH_RT && NCPUS > 1*/
- ret
-ENTRY(_mp_enable_preemption)
-#if MACH_RT && NCPUS > 1
-#if MACH_ASSERT
- movl $CPD_PREEMPTION_LEVEL,%eax
- cmpl $0,%gs:(%eax)
- jg 1f
- pushl %gs:(%eax)
- pushl $2f
- call EXT(panic)
- hlt
- .data
-2: String "_mp_enable_preemption: preemption_level (%d) <= 0!"
- .text
+
+LEAF_ENTRY(lck_mtx_lock_mark_destroyed)
+ mov %rdi, %rdx
1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION(%eax)
-#endif /* MACH_RT && NCPUS > 1 */
- ret
+ 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
+ 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
-ENTRY(_mp_enable_preemption_no_check)
-#if MACH_RT && NCPUS > 1
-#if MACH_ASSERT
- movl $CPD_PREEMPTION_LEVEL,%eax
- cmpl $0,%gs:(%eax)
- jg 1f
- pushl $2f
- call EXT(panic)
+LEAF_ENTRY(preemption_underflow_panic)
+ FRAME
+ incl %gs:CPU_PREEMPTION_LEVEL
+ ALIGN_STACK()
+ LOAD_STRING_ARG0(16f)
+ CALL_PANIC()
hlt
.data
-2: String "_mp_enable_preemption_no_check: preemption_level <= 0!"
+16: String "Preemption level underflow, possible cause unlocking an unlocked mutex or spinlock"
.text
-1:
-#endif /* MACH_ASSERT */
- _ENABLE_PREEMPTION_NO_CHECK(%eax)
-#endif /* MACH_RT && NCPUS > 1 */
- ret
-
-
-ENTRY(i_bit_set)
- movl S_ARG0,%edx
- movl S_ARG1,%eax
- lock
- bts %dl,(%eax)
- ret
-ENTRY(i_bit_clear)
- movl S_ARG0,%edx
- movl S_ARG1,%eax
- lock
- btr %dl,(%eax)
- ret
-ENTRY(bit_lock)
- movl S_ARG0,%ecx
- movl S_ARG1,%eax
-1:
- lock
- bts %ecx,(%eax)
- jb 1b
- ret
-
-ENTRY(bit_lock_try)
- movl S_ARG0,%ecx
- movl S_ARG1,%eax
- lock
- bts %ecx,(%eax)
- jb bit_lock_failed
- ret /* %eax better not be null ! */
-bit_lock_failed:
- xorl %eax,%eax
- ret
-
-ENTRY(bit_unlock)
- movl S_ARG0,%ecx
- movl S_ARG1,%eax
- lock
- btr %ecx,(%eax)
- ret
projects / apple / xnu.git / blobdiff