/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" #if defined(lint) || defined(__lint) #include #include #include #include #include #else /* __lint */ #include "assym.h" #endif /* __lint */ #include #include #include #include #include /* * lock_try(lp), ulock_try(lp) * - returns non-zero on success. * - doesn't block interrupts so don't use this to spin on a lock. * * ulock_try() is for a lock in the user address space. */ #if defined(lint) || defined(__lint) /* ARGSUSED */ int lock_try(lock_t *lp) { return (0); } /* ARGSUSED */ int lock_spin_try(lock_t *lp) { return (0); } /* ARGSUSED */ int ulock_try(lock_t *lp) { return (0); } #else /* __lint */ .globl kernelbase #if defined(__amd64) ENTRY(lock_try) movb $-1, %dl movzbq %dl, %rax xchgb %dl, (%rdi) xorb %dl, %al .lock_try_lockstat_patch_point: ret testb %al, %al jnz 0f ret 0: movq %gs:CPU_THREAD, %rdx /* rdx = thread addr */ movq %rdi, %rsi /* rsi = lock addr */ movl $LS_LOCK_TRY_ACQUIRE, %edi /* edi = event */ jmp lockstat_wrapper SET_SIZE(lock_try) ENTRY(lock_spin_try) movb $-1, %dl movzbq %dl, %rax xchgb %dl, (%rdi) xorb %dl, %al ret SET_SIZE(lock_spin_try) ENTRY(ulock_try) #ifdef DEBUG movq kernelbase(%rip), %rax cmpq %rax, %rdi /* test uaddr < kernelbase */ jb ulock_pass /* uaddr < kernelbase, proceed */ movq %rdi, %r12 /* preserve lock ptr for debugging */ leaq .ulock_panic_msg(%rip), %rdi pushq %rbp /* align stack properly */ movq %rsp, %rbp xorl %eax, %eax /* clear for varargs */ call panic #endif /* DEBUG */ ulock_pass: movl $1, %eax xchgb %al, (%rdi) xorb $1, %al ret SET_SIZE(ulock_try) #else ENTRY(lock_try) movl $1,%edx movl 4(%esp),%ecx /* ecx = lock addr */ xorl %eax,%eax xchgb %dl, (%ecx) /* using dl will avoid partial */ testb %dl,%dl /* stalls on P6 ? */ setz %al .lock_try_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread addr */ testl %eax, %eax jz 0f movl $LS_LOCK_TRY_ACQUIRE, %eax jmp lockstat_wrapper 0: ret SET_SIZE(lock_try) ENTRY(lock_spin_try) movl $-1,%edx movl 4(%esp),%ecx /* ecx = lock addr */ xorl %eax,%eax xchgb %dl, (%ecx) /* using dl will avoid partial */ testb %dl,%dl /* stalls on P6 ? */ setz %al ret SET_SIZE(lock_spin_try) ENTRY(ulock_try) #ifdef DEBUG movl kernelbase, %eax cmpl %eax, 4(%esp) /* test uaddr < kernelbase */ jb ulock_pass /* uaddr < kernelbase, proceed */ pushl $.ulock_panic_msg call panic #endif /* DEBUG */ ulock_pass: movl $1,%eax movl 4(%esp),%ecx xchgb %al, (%ecx) xorb $1, %al ret SET_SIZE(ulock_try) #endif /* !__amd64 */ #ifdef DEBUG .data .ulock_panic_msg: .string "ulock_try: Argument is above kernelbase" .text #endif /* DEBUG */ #endif /* __lint */ /* * lock_clear(lp) * - unlock lock without changing interrupt priority level. */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void lock_clear(lock_t *lp) {} /* ARGSUSED */ void ulock_clear(lock_t *lp) {} #else /* __lint */ #if defined(__amd64) ENTRY(lock_clear) movb $0, (%rdi) .lock_clear_lockstat_patch_point: ret movq %rdi, %rsi /* rsi = lock addr */ movq %gs:CPU_THREAD, %rdx /* rdx = thread addr */ movl $LS_LOCK_CLEAR_RELEASE, %edi /* edi = event */ jmp lockstat_wrapper SET_SIZE(lock_clear) ENTRY(ulock_clear) #ifdef DEBUG movq kernelbase(%rip), %rcx cmpq %rcx, %rdi /* test uaddr < kernelbase */ jb ulock_clr /* uaddr < kernelbase, proceed */ leaq .ulock_clear_msg(%rip), %rdi pushq %rbp /* align stack properly */ movq %rsp, %rbp xorl %eax, %eax /* clear for varargs */ call panic #endif ulock_clr: movb $0, (%rdi) ret SET_SIZE(ulock_clear) #else ENTRY(lock_clear) movl 4(%esp), %eax movb $0, (%eax) .lock_clear_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread addr */ movl %eax, %ecx /* ecx = lock pointer */ movl $LS_LOCK_CLEAR_RELEASE, %eax jmp lockstat_wrapper SET_SIZE(lock_clear) ENTRY(ulock_clear) #ifdef DEBUG movl kernelbase, %ecx cmpl %ecx, 4(%esp) /* test uaddr < kernelbase */ jb ulock_clr /* uaddr < kernelbase, proceed */ pushl $.ulock_clear_msg call panic #endif ulock_clr: movl 4(%esp),%eax xorl %ecx,%ecx movb %cl, (%eax) ret SET_SIZE(ulock_clear) #endif /* !__amd64 */ #ifdef DEBUG .data .ulock_clear_msg: .string "ulock_clear: Argument is above kernelbase" .text #endif /* DEBUG */ #endif /* __lint */ /* * lock_set_spl(lock_t *lp, int new_pil, u_short *old_pil) * Drops lp, sets pil to new_pil, stores old pil in *old_pil. */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void lock_set_spl(lock_t *lp, int new_pil, u_short *old_pil) {} #else /* __lint */ #if defined(__amd64) ENTRY(lock_set_spl) pushq %rbp movq %rsp, %rbp subq $32, %rsp movl %esi, 8(%rsp) /* save priority level */ movq %rdx, 16(%rsp) /* save old pil ptr */ movq %rdi, 24(%rsp) /* save lock pointer */ movl %esi, %edi /* pass priority level */ call splr /* raise priority level */ movq 24(%rsp), %rdi /* rdi = lock addr */ movb $-1, %dl xchgb %dl, (%rdi) /* try to set lock */ testb %dl, %dl /* did we get the lock? ... */ jnz .lss_miss /* ... no, go to C for the hard case */ movq 16(%rsp), %rdx /* rdx = old pil addr */ movw %ax, (%rdx) /* store old pil */ leave .lock_set_spl_lockstat_patch_point: ret movq %rdi, %rsi /* rsi = lock addr */ movq %gs:CPU_THREAD, %rdx /* rdx = thread addr */ movl $LS_LOCK_SET_SPL_ACQUIRE, %edi jmp lockstat_wrapper .lss_miss: movl 8(%rsp), %esi /* new_pil */ movq 16(%rsp), %rdx /* old_pil_addr */ movl %eax, %ecx /* original pil */ leave /* unwind stack */ jmp lock_set_spl_spin SET_SIZE(lock_set_spl) #else ENTRY(lock_set_spl) movl 8(%esp), %eax /* get priority level */ pushl %eax call splr /* raise priority level */ movl 8(%esp), %ecx /* ecx = lock addr */ movl $-1, %edx addl $4, %esp xchgb %dl, (%ecx) /* try to set lock */ testb %dl, %dl /* did we get the lock? ... */ movl 12(%esp), %edx /* edx = olp pil addr (ZF unaffected) */ jnz .lss_miss /* ... no, go to C for the hard case */ movw %ax, (%edx) /* store old pil */ .lock_set_spl_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread addr*/ movl $LS_LOCK_SET_SPL_ACQUIRE, %eax jmp lockstat_wrapper .lss_miss: pushl %eax /* original pil */ pushl %edx /* old_pil addr */ pushl 16(%esp) /* new_pil */ pushl %ecx /* lock addr */ call lock_set_spl_spin addl $16, %esp ret SET_SIZE(lock_set_spl) #endif /* !__amd64 */ #endif /* __lint */ /* * void * lock_init(lp) */ #if defined(__lint) /* ARGSUSED */ void lock_init(lock_t *lp) {} #else /* __lint */ #if defined(__amd64) ENTRY(lock_init) movb $0, (%rdi) ret SET_SIZE(lock_init) #else ENTRY(lock_init) movl 4(%esp), %eax movb $0, (%eax) ret SET_SIZE(lock_init) #endif /* !__amd64 */ #endif /* __lint */ /* * void * lock_set(lp) */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void lock_set(lock_t *lp) {} #else /* __lint */ #if defined(__amd64) ENTRY(lock_set) movb $-1, %dl xchgb %dl, (%rdi) /* try to set lock */ testb %dl, %dl /* did we get it? */ jnz lock_set_spin /* no, go to C for the hard case */ .lock_set_lockstat_patch_point: ret movq %rdi, %rsi /* rsi = lock addr */ movq %gs:CPU_THREAD, %rdx /* rdx = thread addr */ movl $LS_LOCK_SET_ACQUIRE, %edi jmp lockstat_wrapper SET_SIZE(lock_set) #else ENTRY(lock_set) movl 4(%esp), %ecx /* ecx = lock addr */ movl $-1, %edx xchgb %dl, (%ecx) /* try to set lock */ testb %dl, %dl /* did we get it? */ jnz lock_set_spin /* no, go to C for the hard case */ .lock_set_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread addr */ movl $LS_LOCK_SET_ACQUIRE, %eax jmp lockstat_wrapper SET_SIZE(lock_set) #endif /* !__amd64 */ #endif /* __lint */ /* * lock_clear_splx(lp, s) */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void lock_clear_splx(lock_t *lp, int s) {} #else /* __lint */ #if defined(__amd64) ENTRY(lock_clear_splx) movb $0, (%rdi) /* clear lock */ .lock_clear_splx_lockstat_patch_point: jmp 0f 0: movl %esi, %edi /* arg for splx */ jmp splx /* let splx do its thing */ .lock_clear_splx_lockstat: pushq %rbp /* align stack properly */ movq %rsp, %rbp subq $16, %rsp /* space to save args across splx */ movq %rdi, 8(%rsp) /* save lock ptr across splx call */ movl %esi, %edi /* arg for splx */ call splx /* lower the priority */ movq 8(%rsp), %rsi /* rsi = lock ptr */ leave /* unwind stack */ movq %gs:CPU_THREAD, %rdx /* rdx = thread addr */ movl $LS_LOCK_CLEAR_SPLX_RELEASE, %edi jmp lockstat_wrapper SET_SIZE(lock_clear_splx) #if defined(__GNUC_AS__) #define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL \ (.lock_clear_splx_lockstat - .lock_clear_splx_lockstat_patch_point - 2) #define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT \ (.lock_clear_splx_lockstat_patch_point + 1) #else #define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL \ [.lock_clear_splx_lockstat - .lock_clear_splx_lockstat_patch_point - 2] #define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT \ [.lock_clear_splx_lockstat_patch_point + 1] #endif #else ENTRY(lock_clear_splx) LOADCPU(%ecx) /* ecx = cpu pointer */ movl 4(%esp), %eax /* eax = lock addr */ movl 8(%esp), %edx /* edx = desired pil */ movb $0, (%eax) /* clear lock */ cli /* disable interrupts */ call spl /* magic calling sequence */ .lock_clear_splx_lockstat_patch_point: ret movl 4(%esp), %ecx /* ecx = lock pointer */ movl %gs:CPU_THREAD, %edx /* edx = thread addr */ movl $LS_LOCK_CLEAR_SPLX_RELEASE, %eax jmp lockstat_wrapper SET_SIZE(lock_clear_splx) #endif /* !__amd64 */ #endif /* __lint */ /* * mutex_enter() and mutex_exit(). * * These routines handle the simple cases of mutex_enter() (adaptive * lock, not held) and mutex_exit() (adaptive lock, held, no waiters). * If anything complicated is going on we punt to mutex_vector_enter(). * * mutex_tryenter() is similar to mutex_enter() but returns zero if * the lock cannot be acquired, nonzero on success. * * If mutex_exit() gets preempted in the window between checking waiters * and clearing the lock, we can miss wakeups. Disabling preemption * in the mutex code is prohibitively expensive, so instead we detect * mutex preemption by examining the trapped PC in the interrupt path. * If we interrupt a thread in mutex_exit() that has not yet cleared * the lock, cmnint() resets its PC back to the beginning of * mutex_exit() so it will check again for waiters when it resumes. * * The lockstat code below is activated when the lockstat driver * calls lockstat_hot_patch() to hot-patch the kernel mutex code. * Note that we don't need to test lockstat_event_mask here -- we won't * patch this code in unless we're gathering ADAPTIVE_HOLD lockstats. */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void mutex_enter(kmutex_t *lp) {} /* ARGSUSED */ int mutex_tryenter(kmutex_t *lp) { return (0); } /* ARGSUSED */ int mutex_adaptive_tryenter(mutex_impl_t *lp) { return (0); } /* ARGSUSED */ void mutex_exit(kmutex_t *lp) {} #else #if defined(__amd64) ENTRY_NP(mutex_enter) movq %gs:CPU_THREAD, %rdx /* rdx = thread ptr */ xorl %eax, %eax /* rax = 0 (unheld adaptive) */ lock cmpxchgq %rdx, (%rdi) jnz mutex_vector_enter .mutex_enter_lockstat_patch_point: #if defined(OPTERON_WORKAROUND_6323525) .mutex_enter_6323525_patch_point: ret /* nop space for lfence */ nop nop .mutex_enter_lockstat_6323525_patch_point: /* new patch point if lfence */ nop #else /* OPTERON_WORKAROUND_6323525 */ ret #endif /* OPTERON_WORKAROUND_6323525 */ movq %rdi, %rsi movl $LS_MUTEX_ENTER_ACQUIRE, %edi /* * expects %rdx=thread, %rsi=lock, %edi=lockstat event */ ALTENTRY(lockstat_wrapper) incb T_LOCKSTAT(%rdx) /* curthread->t_lockstat++ */ leaq lockstat_probemap(%rip), %rax movl (%rax, %rdi, DTRACE_IDSIZE), %eax testl %eax, %eax /* check for non-zero probe */ jz 1f pushq %rbp /* align stack properly */ movq %rsp, %rbp movl %eax, %edi call *lockstat_probe leave /* unwind stack */ 1: movq %gs:CPU_THREAD, %rdx /* reload thread ptr */ decb T_LOCKSTAT(%rdx) /* curthread->t_lockstat-- */ movl $1, %eax /* return success if tryenter */ ret SET_SIZE(lockstat_wrapper) SET_SIZE(mutex_enter) /* * expects %rcx=thread, %rdx=arg, %rsi=lock, %edi=lockstat event */ ENTRY(lockstat_wrapper_arg) incb T_LOCKSTAT(%rcx) /* curthread->t_lockstat++ */ leaq lockstat_probemap(%rip), %rax movl (%rax, %rdi, DTRACE_IDSIZE), %eax testl %eax, %eax /* check for non-zero probe */ jz 1f pushq %rbp /* align stack properly */ movq %rsp, %rbp movl %eax, %edi call *lockstat_probe leave /* unwind stack */ 1: movq %gs:CPU_THREAD, %rdx /* reload thread ptr */ decb T_LOCKSTAT(%rdx) /* curthread->t_lockstat-- */ movl $1, %eax /* return success if tryenter */ ret SET_SIZE(lockstat_wrapper_arg) ENTRY(mutex_tryenter) movq %gs:CPU_THREAD, %rdx /* rdx = thread ptr */ xorl %eax, %eax /* rax = 0 (unheld adaptive) */ lock cmpxchgq %rdx, (%rdi) jnz mutex_vector_tryenter not %eax /* return success (nonzero) */ #if defined(OPTERON_WORKAROUND_6323525) .mutex_tryenter_lockstat_patch_point: .mutex_tryenter_6323525_patch_point: ret /* nop space for lfence */ nop nop .mutex_tryenter_lockstat_6323525_patch_point: /* new patch point if lfence */ nop #else /* OPTERON_WORKAROUND_6323525 */ .mutex_tryenter_lockstat_patch_point: ret #endif /* OPTERON_WORKAROUND_6323525 */ movq %rdi, %rsi movl $LS_MUTEX_ENTER_ACQUIRE, %edi jmp lockstat_wrapper SET_SIZE(mutex_tryenter) ENTRY(mutex_adaptive_tryenter) movq %gs:CPU_THREAD, %rdx /* rdx = thread ptr */ xorl %eax, %eax /* rax = 0 (unheld adaptive) */ lock cmpxchgq %rdx, (%rdi) jnz 0f not %eax /* return success (nonzero) */ #if defined(OPTERON_WORKAROUND_6323525) .mutex_atryenter_6323525_patch_point: ret /* nop space for lfence */ nop nop nop #else /* OPTERON_WORKAROUND_6323525 */ ret #endif /* OPTERON_WORKAROUND_6323525 */ 0: xorl %eax, %eax /* return failure */ ret SET_SIZE(mutex_adaptive_tryenter) .globl mutex_exit_critical_start ENTRY(mutex_exit) mutex_exit_critical_start: /* If interrupted, restart here */ movq %gs:CPU_THREAD, %rdx cmpq %rdx, (%rdi) jne mutex_vector_exit /* wrong type or wrong owner */ movq $0, (%rdi) /* clear owner AND lock */ .mutex_exit_critical_end: .mutex_exit_lockstat_patch_point: ret movq %rdi, %rsi movl $LS_MUTEX_EXIT_RELEASE, %edi jmp lockstat_wrapper SET_SIZE(mutex_exit) .globl mutex_exit_critical_size .type mutex_exit_critical_size, @object .align CPTRSIZE mutex_exit_critical_size: .quad .mutex_exit_critical_end - mutex_exit_critical_start SET_SIZE(mutex_exit_critical_size) #else ENTRY_NP(mutex_enter) movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl 4(%esp), %ecx /* ecx = lock ptr */ xorl %eax, %eax /* eax = 0 (unheld adaptive) */ lock cmpxchgl %edx, (%ecx) jnz mutex_vector_enter #if defined(OPTERON_WORKAROUND_6323525) .mutex_enter_lockstat_patch_point: .mutex_enter_6323525_patch_point: ret /* nop space for lfence */ nop nop .mutex_enter_lockstat_6323525_patch_point: /* new patch point if lfence */ nop #else /* OPTERON_WORKAROUND_6323525 */ .mutex_enter_lockstat_patch_point: ret #endif /* OPTERON_WORKAROUND_6323525 */ movl $LS_MUTEX_ENTER_ACQUIRE, %eax ALTENTRY(lockstat_wrapper) /* expects edx=thread, ecx=lock, */ /* eax=lockstat event */ pushl %ebp /* buy a frame */ movl %esp, %ebp incb T_LOCKSTAT(%edx) /* curthread->t_lockstat++ */ pushl %edx /* save thread pointer */ movl $lockstat_probemap, %edx movl (%edx, %eax, DTRACE_IDSIZE), %eax testl %eax, %eax /* check for non-zero probe */ jz 1f pushl %ecx /* push lock */ pushl %eax /* push probe ID */ call *lockstat_probe addl $8, %esp 1: popl %edx /* restore thread pointer */ decb T_LOCKSTAT(%edx) /* curthread->t_lockstat-- */ movl $1, %eax /* return success if tryenter */ popl %ebp /* pop off frame */ ret SET_SIZE(lockstat_wrapper) SET_SIZE(mutex_enter) ENTRY(lockstat_wrapper_arg) /* expects edx=thread, ecx=lock, */ /* eax=lockstat event, pushed arg */ incb T_LOCKSTAT(%edx) /* curthread->t_lockstat++ */ pushl %edx /* save thread pointer */ movl $lockstat_probemap, %edx movl (%edx, %eax, DTRACE_IDSIZE), %eax testl %eax, %eax /* check for non-zero probe */ jz 1f pushl %ebp /* save %ebp */ pushl 8(%esp) /* push arg1 */ movl %ebp, 12(%esp) /* fake up the stack frame */ movl %esp, %ebp /* fake up base pointer */ addl $12, %ebp /* adjust faked base pointer */ pushl %ecx /* push lock */ pushl %eax /* push probe ID */ call *lockstat_probe addl $12, %esp /* adjust for arguments */ popl %ebp /* pop frame */ 1: popl %edx /* restore thread pointer */ decb T_LOCKSTAT(%edx) /* curthread->t_lockstat-- */ movl $1, %eax /* return success if tryenter */ addl $4, %esp /* pop argument */ ret SET_SIZE(lockstat_wrapper_arg) ENTRY(mutex_tryenter) movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl 4(%esp), %ecx /* ecx = lock ptr */ xorl %eax, %eax /* eax = 0 (unheld adaptive) */ lock cmpxchgl %edx, (%ecx) jnz mutex_vector_tryenter movl %ecx, %eax #if defined(OPTERON_WORKAROUND_6323525) .mutex_tryenter_lockstat_patch_point: .mutex_tryenter_6323525_patch_point: ret /* nop space for lfence */ nop nop .mutex_tryenter_lockstat_6323525_patch_point: /* new patch point if lfence */ nop #else /* OPTERON_WORKAROUND_6323525 */ .mutex_tryenter_lockstat_patch_point: ret #endif /* OPTERON_WORKAROUND_6323525 */ movl $LS_MUTEX_ENTER_ACQUIRE, %eax jmp lockstat_wrapper SET_SIZE(mutex_tryenter) ENTRY(mutex_adaptive_tryenter) movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl 4(%esp), %ecx /* ecx = lock ptr */ xorl %eax, %eax /* eax = 0 (unheld adaptive) */ lock cmpxchgl %edx, (%ecx) jnz 0f movl %ecx, %eax #if defined(OPTERON_WORKAROUND_6323525) .mutex_atryenter_6323525_patch_point: ret /* nop space for lfence */ nop nop nop #else /* OPTERON_WORKAROUND_6323525 */ ret #endif /* OPTERON_WORKAROUND_6323525 */ 0: xorl %eax, %eax ret SET_SIZE(mutex_adaptive_tryenter) .globl mutex_exit_critical_size .globl mutex_exit_critical_start ENTRY(mutex_exit) mutex_exit_critical_start: /* If interrupted, restart here */ movl %gs:CPU_THREAD, %edx movl 4(%esp), %ecx cmpl %edx, (%ecx) jne mutex_vector_exit /* wrong type or wrong owner */ movl $0, (%ecx) /* clear owner AND lock */ .mutex_exit_critical_end: .mutex_exit_lockstat_patch_point: ret movl $LS_MUTEX_EXIT_RELEASE, %eax jmp lockstat_wrapper SET_SIZE(mutex_exit) .globl mutex_exit_critical_size .type mutex_exit_critical_size, @object .align CPTRSIZE mutex_exit_critical_size: .long .mutex_exit_critical_end - mutex_exit_critical_start SET_SIZE(mutex_exit_critical_size) #endif /* !__amd64 */ #endif /* __lint */ /* * rw_enter() and rw_exit(). * * These routines handle the simple cases of rw_enter (write-locking an unheld * lock or read-locking a lock that's neither write-locked nor write-wanted) * and rw_exit (no waiters or not the last reader). If anything complicated * is going on we punt to rw_enter_sleep() and rw_exit_wakeup(), respectively. */ #if defined(lint) || defined(__lint) /* ARGSUSED */ void rw_enter(krwlock_t *lp, krw_t rw) {} /* ARGSUSED */ void rw_exit(krwlock_t *lp) {} #else /* __lint */ #if defined(__amd64) ENTRY(rw_enter) movq %gs:CPU_THREAD, %rdx /* rdx = thread ptr */ cmpl $RW_WRITER, %esi je .rw_write_enter incl T_KPRI_REQ(%rdx) /* THREAD_KPRI_REQUEST() */ movq (%rdi), %rax /* rax = old rw_wwwh value */ testl $RW_WRITE_LOCKED|RW_WRITE_WANTED, %eax jnz rw_enter_sleep leaq RW_READ_LOCK(%rax), %rdx /* rdx = new rw_wwwh value */ lock cmpxchgq %rdx, (%rdi) /* try to grab read lock */ jnz rw_enter_sleep .rw_read_enter_lockstat_patch_point: ret movq %gs:CPU_THREAD, %rcx /* rcx = thread ptr */ movq %rdi, %rsi /* rsi = lock ptr */ movl $LS_RW_ENTER_ACQUIRE, %edi movl $RW_READER, %edx jmp lockstat_wrapper_arg .rw_write_enter: orq $RW_WRITE_LOCKED, %rdx /* rdx = write-locked value */ xorl %eax, %eax /* rax = unheld value */ lock cmpxchgq %rdx, (%rdi) /* try to grab write lock */ jnz rw_enter_sleep #if defined(OPTERON_WORKAROUND_6323525) .rw_write_enter_lockstat_patch_point: .rw_write_enter_6323525_patch_point: ret nop nop .rw_write_enter_lockstat_6323525_patch_point: nop #else /* OPTERON_WORKAROUND_6323525 */ .rw_write_enter_lockstat_patch_point: ret #endif /* OPTERON_WORKAROUND_6323525 */ movq %gs:CPU_THREAD, %rcx /* rcx = thread ptr */ movq %rdi, %rsi /* rsi = lock ptr */ movl $LS_RW_ENTER_ACQUIRE, %edi movl $RW_WRITER, %edx jmp lockstat_wrapper_arg SET_SIZE(rw_enter) ENTRY(rw_exit) movq (%rdi), %rax /* rax = old rw_wwwh value */ cmpl $RW_READ_LOCK, %eax /* single-reader, no waiters? */ jne .rw_not_single_reader xorl %edx, %edx /* rdx = new value (unheld) */ .rw_read_exit: lock cmpxchgq %rdx, (%rdi) /* try to drop read lock */ jnz rw_exit_wakeup movq %gs:CPU_THREAD, %rcx /* rcx = thread ptr */ decl T_KPRI_REQ(%rcx) /* THREAD_KPRI_RELEASE() */ .rw_read_exit_lockstat_patch_point: ret movq %rdi, %rsi /* rsi = lock ptr */ movl $LS_RW_EXIT_RELEASE, %edi movl $RW_READER, %edx jmp lockstat_wrapper_arg .rw_not_single_reader: testl $RW_WRITE_LOCKED, %eax /* write-locked or write-wanted? */ jnz .rw_write_exit leaq -RW_READ_LOCK(%rax), %rdx /* rdx = new value */ cmpl $RW_READ_LOCK, %edx jge .rw_read_exit /* not last reader, safe to drop */ jmp rw_exit_wakeup /* last reader with waiters */ .rw_write_exit: movq %gs:CPU_THREAD, %rax /* rax = thread ptr */ xorl %edx, %edx /* rdx = new value (unheld) */ orq $RW_WRITE_LOCKED, %rax /* eax = write-locked value */ lock cmpxchgq %rdx, (%rdi) /* try to drop read lock */ jnz rw_exit_wakeup .rw_write_exit_lockstat_patch_point: ret movq %gs:CPU_THREAD, %rcx /* rcx = thread ptr */ movq %rdi, %rsi /* rsi - lock ptr */ movl $LS_RW_EXIT_RELEASE, %edi movl $RW_WRITER, %edx jmp lockstat_wrapper_arg SET_SIZE(rw_exit) #else ENTRY(rw_enter) movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl 4(%esp), %ecx /* ecx = lock ptr */ cmpl $RW_WRITER, 8(%esp) je .rw_write_enter incl T_KPRI_REQ(%edx) /* THREAD_KPRI_REQUEST() */ movl (%ecx), %eax /* eax = old rw_wwwh value */ testl $RW_WRITE_LOCKED|RW_WRITE_WANTED, %eax jnz rw_enter_sleep leal RW_READ_LOCK(%eax), %edx /* edx = new rw_wwwh value */ lock cmpxchgl %edx, (%ecx) /* try to grab read lock */ jnz rw_enter_sleep .rw_read_enter_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl $LS_RW_ENTER_ACQUIRE, %eax pushl $RW_READER jmp lockstat_wrapper_arg .rw_write_enter: orl $RW_WRITE_LOCKED, %edx /* edx = write-locked value */ xorl %eax, %eax /* eax = unheld value */ lock cmpxchgl %edx, (%ecx) /* try to grab write lock */ jnz rw_enter_sleep #if defined(OPTERON_WORKAROUND_6323525) .rw_write_enter_lockstat_patch_point: .rw_write_enter_6323525_patch_point: ret nop nop .rw_write_enter_lockstat_6323525_patch_point: nop #else /* OPTERON_WORKAROUND_6323525 */ .rw_write_enter_lockstat_patch_point: ret #endif /* OPTERON_WORKAROUND_6323525 */ movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl $LS_RW_ENTER_ACQUIRE, %eax pushl $RW_WRITER jmp lockstat_wrapper_arg SET_SIZE(rw_enter) ENTRY(rw_exit) movl 4(%esp), %ecx /* ecx = lock ptr */ movl (%ecx), %eax /* eax = old rw_wwwh value */ cmpl $RW_READ_LOCK, %eax /* single-reader, no waiters? */ jne .rw_not_single_reader xorl %edx, %edx /* edx = new value (unheld) */ .rw_read_exit: lock cmpxchgl %edx, (%ecx) /* try to drop read lock */ jnz rw_exit_wakeup movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ decl T_KPRI_REQ(%edx) /* THREAD_KPRI_RELEASE() */ .rw_read_exit_lockstat_patch_point: ret movl $LS_RW_EXIT_RELEASE, %eax pushl $RW_READER jmp lockstat_wrapper_arg .rw_not_single_reader: testl $RW_WRITE_LOCKED, %eax /* write-locked or write-wanted? */ jnz .rw_write_exit leal -RW_READ_LOCK(%eax), %edx /* edx = new value */ cmpl $RW_READ_LOCK, %edx jge .rw_read_exit /* not last reader, safe to drop */ jmp rw_exit_wakeup /* last reader with waiters */ .rw_write_exit: movl %gs:CPU_THREAD, %eax /* eax = thread ptr */ xorl %edx, %edx /* edx = new value (unheld) */ orl $RW_WRITE_LOCKED, %eax /* eax = write-locked value */ lock cmpxchgl %edx, (%ecx) /* try to drop read lock */ jnz rw_exit_wakeup .rw_write_exit_lockstat_patch_point: ret movl %gs:CPU_THREAD, %edx /* edx = thread ptr */ movl $LS_RW_EXIT_RELEASE, %eax pushl $RW_WRITER jmp lockstat_wrapper_arg SET_SIZE(rw_exit) #endif /* !__amd64 */ #endif /* __lint */ #if defined(OPTERON_WORKAROUND_6323525) #if defined(lint) || defined(__lint) int workaround_6323525_patched; void patch_workaround_6323525(void) {} #else /* lint */ /* * If it is necessary to patch the lock enter routines with the lfence * workaround, workaround_6323525_patched is set to a non-zero value so that * the lockstat_hat_patch routine can patch to the new location of the 'ret' * instruction. */ DGDEF3(workaround_6323525_patched, 4, 4) .long 0 #if defined(__amd64) #define HOT_MUTEX_PATCH(srcaddr, dstaddr, size) \ movq $size, %rbx; \ movq $dstaddr, %r13; \ addq %rbx, %r13; \ movq $srcaddr, %r12; \ addq %rbx, %r12; \ 0: \ decq %r13; \ decq %r12; \ movzbl (%r12), %esi; \ movq $1, %rdx; \ movq %r13, %rdi; \ call hot_patch_kernel_text; \ decq %rbx; \ testq %rbx, %rbx; \ jg 0b; /* * patch_workaround_6323525: provide workaround for 6323525 * * The workaround is to place a fencing instruction (lfence) between the * mutex operation and the subsequent read-modify-write instruction. * * This routine hot patches the lfence instruction on top of the space * reserved by nops in the lock enter routines. */ ENTRY_NP(patch_workaround_6323525) pushq %rbp movq %rsp, %rbp pushq %r12 pushq %r13 pushq %rbx /* * lockstat_hot_patch() to use the alternate lockstat workaround * 6323525 patch points (points past the lfence instruction to the * new ret) when workaround_6323525_patched is set. */ movl $1, workaround_6323525_patched /* * patch ret/nop/nop/nop to lfence/ret at the end of the lock enter * routines. The 4 bytes are patched in reverse order so that the * the existing ret is overwritten last. This provides lock enter * sanity during the intermediate patching stages. */ HOT_MUTEX_PATCH(_lfence_insn, .mutex_enter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .mutex_tryenter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .mutex_atryenter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .rw_write_enter_6323525_patch_point, 4) popq %rbx popq %r13 popq %r12 movq %rbp, %rsp popq %rbp ret _lfence_insn: lfence ret SET_SIZE(patch_workaround_6323525) #else /* __amd64 */ #define HOT_MUTEX_PATCH(srcaddr, dstaddr, size) \ movl $size, %ebx; \ movl $srcaddr, %esi; \ addl %ebx, %esi; \ movl $dstaddr, %edi; \ addl %ebx, %edi; \ 0: \ decl %esi; \ decl %edi; \ pushl $1; \ movzbl (%esi), %eax; \ pushl %eax; \ pushl %edi; \ call hot_patch_kernel_text; \ addl $12, %esp; \ decl %ebx; \ testl %ebx, %ebx; \ jg 0b; /* see comments above */ ENTRY_NP(patch_workaround_6323525) pushl %ebp movl %esp, %ebp pushl %ebx pushl %esi pushl %edi movl $1, workaround_6323525_patched HOT_MUTEX_PATCH(_lfence_insn, .mutex_enter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .mutex_tryenter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .mutex_atryenter_6323525_patch_point, 4) HOT_MUTEX_PATCH(_lfence_insn, .rw_write_enter_6323525_patch_point, 4) popl %edi popl %esi popl %ebx movl %ebp, %esp popl %ebp ret _lfence_insn: .byte 0xf, 0xae, 0xe8 / [lfence instruction] ret SET_SIZE(patch_workaround_6323525) #endif /* !__amd64 */ #endif /* !lint */ #endif /* OPTERON_WORKAROUND_6323525 */ #if defined(lint) || defined(__lint) void lockstat_hot_patch(void) {} #else #if defined(__amd64) #define HOT_PATCH(addr, event, active_instr, normal_instr, len) \ movq $normal_instr, %rsi; \ movq $active_instr, %rdi; \ leaq lockstat_probemap(%rip), %rax; \ movl _MUL(event, DTRACE_IDSIZE)(%rax), %eax; \ testl %eax, %eax; \ jz 9f; \ movq %rdi, %rsi; \ 9: \ movq $len, %rdx; \ movq $addr, %rdi; \ call hot_patch_kernel_text #else #define HOT_PATCH(addr, event, active_instr, normal_instr, len) \ movl $normal_instr, %ecx; \ movl $active_instr, %edx; \ movl $lockstat_probemap, %eax; \ movl _MUL(event, DTRACE_IDSIZE)(%eax), %eax; \ testl %eax, %eax; \ jz . + 4; \ movl %edx, %ecx; \ pushl $len; \ pushl %ecx; \ pushl $addr; \ call hot_patch_kernel_text; \ addl $12, %esp; #endif /* !__amd64 */ ENTRY(lockstat_hot_patch) #if defined(__amd64) pushq %rbp /* align stack properly */ movq %rsp, %rbp #endif /* __amd64 */ #if defined(OPTERON_WORKAROUND_6323525) cmpl $0, workaround_6323525_patched je 1f HOT_PATCH(.mutex_enter_lockstat_6323525_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.mutex_tryenter_lockstat_6323525_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_write_enter_lockstat_6323525_patch_point, LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) jmp 2f 1: HOT_PATCH(.mutex_enter_lockstat_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.mutex_tryenter_lockstat_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_write_enter_lockstat_patch_point, LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) 2: #else /* OPTERON_WORKAROUND_6323525 */ HOT_PATCH(.mutex_enter_lockstat_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.mutex_tryenter_lockstat_patch_point, LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_write_enter_lockstat_patch_point, LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) #endif /* !OPTERON_WORKAROUND_6323525 */ HOT_PATCH(.mutex_exit_lockstat_patch_point, LS_MUTEX_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_read_enter_lockstat_patch_point, LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_write_exit_lockstat_patch_point, LS_RW_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.rw_read_exit_lockstat_patch_point, LS_RW_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.lock_set_lockstat_patch_point, LS_LOCK_SET_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.lock_try_lockstat_patch_point, LS_LOCK_TRY_ACQUIRE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.lock_clear_lockstat_patch_point, LS_LOCK_CLEAR_RELEASE, NOP_INSTR, RET_INSTR, 1) HOT_PATCH(.lock_set_spl_lockstat_patch_point, LS_LOCK_SET_SPL_ACQUIRE, NOP_INSTR, RET_INSTR, 1) #if defined(__amd64) HOT_PATCH(LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT, LS_LOCK_CLEAR_SPLX_RELEASE, LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL, 0, 1); #else HOT_PATCH(.lock_clear_splx_lockstat_patch_point, LS_LOCK_CLEAR_SPLX_RELEASE, NOP_INSTR, RET_INSTR, 1) #endif /* !__amd64 */ #if defined(__amd64) leave /* unwind stack */ #endif /* __amd64 */ ret SET_SIZE(lockstat_hot_patch) #endif /* __lint */ #if defined(lint) || defined(__lint) /* XX64 membar_*() should be inlines */ void membar_enter(void) {} void membar_exit(void) {} void membar_producer(void) {} void membar_consumer(void) {} #else /* __lint */ #if defined(__amd64) ENTRY(membar_enter) ALTENTRY(membar_exit) mfence /* lighter weight than lock; xorq $0,(%rsp) */ ret SET_SIZE(membar_exit) SET_SIZE(membar_enter) ENTRY(membar_producer) sfence ret SET_SIZE(membar_producer) ENTRY(membar_consumer) lfence ret SET_SIZE(membar_consumer) #else ENTRY(membar_enter) ALTENTRY(membar_exit) lock xorl $0, (%esp) ret SET_SIZE(membar_exit) SET_SIZE(membar_enter) /* * On machines that support sfence and lfence, these * memory barriers can be more precisely implemented * without causing the whole world to stop */ ENTRY(membar_producer) .globl _patch_sfence_ret _patch_sfence_ret: /* c.f. membar #StoreStore */ lock xorl $0, (%esp) ret SET_SIZE(membar_producer) ENTRY(membar_consumer) .globl _patch_lfence_ret _patch_lfence_ret: /* c.f. membar #LoadLoad */ lock xorl $0, (%esp) ret SET_SIZE(membar_consumer) #endif /* !__amd64 */ #endif /* __lint */ /* * thread_onproc() * Set thread in onproc state for the specified CPU. * Also set the thread lock pointer to the CPU's onproc lock. * Since the new lock isn't held, the store ordering is important. * If not done in assembler, the compiler could reorder the stores. */ #if defined(lint) || defined(__lint) void thread_onproc(kthread_id_t t, cpu_t *cp) { t->t_state = TS_ONPROC; t->t_lockp = &cp->cpu_thread_lock; } #else /* __lint */ #if defined(__amd64) ENTRY(thread_onproc) addq $CPU_THREAD_LOCK, %rsi /* pointer to disp_lock while running */ movl $ONPROC_THREAD, T_STATE(%rdi) /* set state to TS_ONPROC */ movq %rsi, T_LOCKP(%rdi) /* store new lock pointer */ ret SET_SIZE(thread_onproc) #else ENTRY(thread_onproc) movl 4(%esp), %eax movl 8(%esp), %ecx addl $CPU_THREAD_LOCK, %ecx /* pointer to disp_lock while running */ movl $ONPROC_THREAD, T_STATE(%eax) /* set state to TS_ONPROC */ movl %ecx, T_LOCKP(%eax) /* store new lock pointer */ ret SET_SIZE(thread_onproc) #endif /* !__amd64 */ #endif /* __lint */