xref: /titanic_51/usr/src/uts/intel/ia32/ml/lock_prim.s (revision aa92d85b088543197e9fb4594eb30d5215fca2c1)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#pragma ident	"%Z%%M%	%I%	%E% SMI"
27
28#if defined(lint) || defined(__lint)
29#include <sys/types.h>
30#include <sys/thread.h>
31#include <sys/cpuvar.h>
32#include <vm/page.h>
33#include <sys/mutex_impl.h>
34#else	/* __lint */
35#include "assym.h"
36#endif	/* __lint */
37
38#include <sys/asm_linkage.h>
39#include <sys/asm_misc.h>
40#include <sys/regset.h>
41#include <sys/rwlock_impl.h>
42#include <sys/lockstat.h>
43
44/*
45 * lock_try(lp), ulock_try(lp)
46 *	- returns non-zero on success.
47 *	- doesn't block interrupts so don't use this to spin on a lock.
48 *
49 * ulock_try() is for a lock in the user address space.
50 */
51
52#if defined(lint) || defined(__lint)
53
54/* ARGSUSED */
55int
56lock_try(lock_t *lp)
57{ return (0); }
58
59/* ARGSUSED */
60int
61lock_spin_try(lock_t *lp)
62{ return (0); }
63
64/* ARGSUSED */
65int
66ulock_try(lock_t *lp)
67{ return (0); }
68
69#else	/* __lint */
70	.globl	kernelbase
71
72#if defined(__amd64)
73
74	ENTRY(lock_try)
75	movb	$-1, %dl
76	movzbq	%dl, %rax
77	xchgb	%dl, (%rdi)
78	xorb	%dl, %al
79.lock_try_lockstat_patch_point:
80	ret
81	testb	%al, %al
82	jnz	0f
83	ret
840:
85	movq	%gs:CPU_THREAD, %rdx	/* rdx = thread addr */
86	movq	%rdi, %rsi		/* rsi = lock addr */
87	movl	$LS_LOCK_TRY_ACQUIRE, %edi /* edi = event */
88	jmp	lockstat_wrapper
89	SET_SIZE(lock_try)
90
91	ENTRY(lock_spin_try)
92	movb	$-1, %dl
93	movzbq	%dl, %rax
94	xchgb	%dl, (%rdi)
95	xorb	%dl, %al
96	ret
97	SET_SIZE(lock_spin_try)
98
99	ENTRY(ulock_try)
100#ifdef DEBUG
101	movq	kernelbase(%rip), %rax
102	cmpq	%rax, %rdi		/* test uaddr < kernelbase */
103	jb	ulock_pass		/*	uaddr < kernelbase, proceed */
104
105	movq	%rdi, %r12		/* preserve lock ptr for debugging */
106	leaq	.ulock_panic_msg(%rip), %rdi
107	pushq	%rbp			/* align stack properly */
108	movq	%rsp, %rbp
109	xorl	%eax, %eax		/* clear for varargs */
110	call	panic
111
112#endif /* DEBUG */
113
114ulock_pass:
115	movl	$1, %eax
116	xchgb	%al, (%rdi)
117	xorb	$1, %al
118	ret
119	SET_SIZE(ulock_try)
120
121#else
122
123	ENTRY(lock_try)
124	movl	$1,%edx
125	movl	4(%esp),%ecx		/* ecx = lock addr */
126	xorl	%eax,%eax
127	xchgb	%dl, (%ecx)		/* using dl will avoid partial */
128	testb	%dl,%dl			/* stalls on P6 ? */
129	setz	%al
130.lock_try_lockstat_patch_point:
131	ret
132	movl	%gs:CPU_THREAD, %edx	/* edx = thread addr */
133	testl	%eax, %eax
134	jz	0f
135	movl	$LS_LOCK_TRY_ACQUIRE, %eax
136	jmp	lockstat_wrapper
1370:
138	ret
139	SET_SIZE(lock_try)
140
141	ENTRY(lock_spin_try)
142	movl	$-1,%edx
143	movl	4(%esp),%ecx		/* ecx = lock addr */
144	xorl	%eax,%eax
145	xchgb	%dl, (%ecx)		/* using dl will avoid partial */
146	testb	%dl,%dl			/* stalls on P6 ? */
147	setz	%al
148	ret
149	SET_SIZE(lock_spin_try)
150
151	ENTRY(ulock_try)
152#ifdef DEBUG
153	movl	kernelbase, %eax
154	cmpl	%eax, 4(%esp)		/* test uaddr < kernelbase */
155	jb	ulock_pass		/* uaddr < kernelbase, proceed */
156
157	pushl	$.ulock_panic_msg
158	call	panic
159
160#endif /* DEBUG */
161
162ulock_pass:
163	movl	$1,%eax
164	movl	4(%esp),%ecx
165	xchgb	%al, (%ecx)
166	xorb	$1, %al
167	ret
168	SET_SIZE(ulock_try)
169
170#endif	/* !__amd64 */
171
172#ifdef DEBUG
173	.data
174.ulock_panic_msg:
175	.string "ulock_try: Argument is above kernelbase"
176	.text
177#endif	/* DEBUG */
178
179#endif	/* __lint */
180
181/*
182 * lock_clear(lp)
183 *	- unlock lock without changing interrupt priority level.
184 */
185
186#if defined(lint) || defined(__lint)
187
188/* ARGSUSED */
189void
190lock_clear(lock_t *lp)
191{}
192
193/* ARGSUSED */
194void
195ulock_clear(lock_t *lp)
196{}
197
198#else	/* __lint */
199
200#if defined(__amd64)
201
202	ENTRY(lock_clear)
203	movb	$0, (%rdi)
204.lock_clear_lockstat_patch_point:
205	ret
206	movq	%rdi, %rsi			/* rsi = lock addr */
207	movq	%gs:CPU_THREAD, %rdx		/* rdx = thread addr */
208	movl	$LS_LOCK_CLEAR_RELEASE, %edi	/* edi = event */
209	jmp	lockstat_wrapper
210	SET_SIZE(lock_clear)
211
212	ENTRY(ulock_clear)
213#ifdef DEBUG
214	movq	kernelbase(%rip), %rcx
215	cmpq	%rcx, %rdi		/* test uaddr < kernelbase */
216	jb	ulock_clr		/*	 uaddr < kernelbase, proceed */
217
218	leaq	.ulock_clear_msg(%rip), %rdi
219	pushq	%rbp			/* align stack properly */
220	movq	%rsp, %rbp
221	xorl	%eax, %eax		/* clear for varargs */
222	call	panic
223#endif
224
225ulock_clr:
226	movb	$0, (%rdi)
227	ret
228	SET_SIZE(ulock_clear)
229
230#else
231
232	ENTRY(lock_clear)
233	movl	4(%esp), %eax
234	movb	$0, (%eax)
235.lock_clear_lockstat_patch_point:
236	ret
237	movl	%gs:CPU_THREAD, %edx		/* edx = thread addr */
238	movl	%eax, %ecx			/* ecx = lock pointer */
239	movl	$LS_LOCK_CLEAR_RELEASE, %eax
240	jmp	lockstat_wrapper
241	SET_SIZE(lock_clear)
242
243	ENTRY(ulock_clear)
244#ifdef DEBUG
245	movl	kernelbase, %ecx
246	cmpl	%ecx, 4(%esp)		/* test uaddr < kernelbase */
247	jb	ulock_clr		/* uaddr < kernelbase, proceed */
248
249	pushl	$.ulock_clear_msg
250	call	panic
251#endif
252
253ulock_clr:
254	movl	4(%esp),%eax
255	xorl	%ecx,%ecx
256	movb	%cl, (%eax)
257	ret
258	SET_SIZE(ulock_clear)
259
260#endif	/* !__amd64 */
261
262#ifdef DEBUG
263	.data
264.ulock_clear_msg:
265	.string "ulock_clear: Argument is above kernelbase"
266	.text
267#endif	/* DEBUG */
268
269
270#endif	/* __lint */
271
272/*
273 * lock_set_spl(lock_t *lp, int new_pil, u_short *old_pil)
274 * Drops lp, sets pil to new_pil, stores old pil in *old_pil.
275 */
276
277#if defined(lint) || defined(__lint)
278
279/* ARGSUSED */
280void
281lock_set_spl(lock_t *lp, int new_pil, u_short *old_pil)
282{}
283
284#else	/* __lint */
285
286#if defined(__amd64)
287
288	ENTRY(lock_set_spl)
289	pushq	%rbp
290	movq	%rsp, %rbp
291	subq	$32, %rsp
292	movl	%esi, 8(%rsp)		/* save priority level */
293	movq	%rdx, 16(%rsp)		/* save old pil ptr */
294	movq	%rdi, 24(%rsp)		/* save lock pointer */
295	movl	%esi, %edi		/* pass priority level */
296	call	splr			/* raise priority level */
297	movq	24(%rsp), %rdi		/* rdi = lock addr */
298	movb	$-1, %dl
299	xchgb	%dl, (%rdi)		/* try to set lock */
300	testb	%dl, %dl		/* did we get the lock? ... */
301	jnz	.lss_miss		/* ... no, go to C for the hard case */
302	movq	16(%rsp), %rdx		/* rdx = old pil addr */
303	movw	%ax, (%rdx)		/* store old pil */
304	leave
305.lock_set_spl_lockstat_patch_point:
306	ret
307	movq	%rdi, %rsi		/* rsi = lock addr */
308	movq	%gs:CPU_THREAD, %rdx	/* rdx = thread addr */
309	movl	$LS_LOCK_SET_SPL_ACQUIRE, %edi
310	jmp	lockstat_wrapper
311.lss_miss:
312	movl	8(%rsp), %esi		/* new_pil */
313	movq	16(%rsp), %rdx		/* old_pil_addr */
314	movl	%eax, %ecx		/* original pil */
315	leave				/* unwind stack */
316	jmp	lock_set_spl_spin
317	SET_SIZE(lock_set_spl)
318
319#else
320
321	ENTRY(lock_set_spl)
322	movl	8(%esp), %eax		/* get priority level */
323	pushl	%eax
324	call	splr			/* raise priority level */
325	movl 	8(%esp), %ecx		/* ecx = lock addr */
326	movl	$-1, %edx
327	addl	$4, %esp
328	xchgb	%dl, (%ecx)		/* try to set lock */
329	testb	%dl, %dl		/* did we get the lock? ... */
330	movl	12(%esp), %edx		/* edx = olp pil addr (ZF unaffected) */
331	jnz	.lss_miss		/* ... no, go to C for the hard case */
332	movw	%ax, (%edx)		/* store old pil */
333.lock_set_spl_lockstat_patch_point:
334	ret
335	movl	%gs:CPU_THREAD, %edx	/* edx = thread addr*/
336	movl	$LS_LOCK_SET_SPL_ACQUIRE, %eax
337	jmp	lockstat_wrapper
338.lss_miss:
339	pushl	%eax			/* original pil */
340	pushl	%edx			/* old_pil addr */
341	pushl	16(%esp)		/* new_pil */
342	pushl	%ecx			/* lock addr */
343	call	lock_set_spl_spin
344	addl	$16, %esp
345	ret
346	SET_SIZE(lock_set_spl)
347
348#endif	/* !__amd64 */
349
350#endif	/* __lint */
351
352/*
353 * void
354 * lock_init(lp)
355 */
356
357#if defined(__lint)
358
359/* ARGSUSED */
360void
361lock_init(lock_t *lp)
362{}
363
364#else	/* __lint */
365
366#if defined(__amd64)
367
368	ENTRY(lock_init)
369	movb	$0, (%rdi)
370	ret
371	SET_SIZE(lock_init)
372
373#else
374
375	ENTRY(lock_init)
376	movl	4(%esp), %eax
377	movb	$0, (%eax)
378	ret
379	SET_SIZE(lock_init)
380
381#endif	/* !__amd64 */
382
383#endif	/* __lint */
384
385/*
386 * void
387 * lock_set(lp)
388 */
389
390#if defined(lint) || defined(__lint)
391
392/* ARGSUSED */
393void
394lock_set(lock_t *lp)
395{}
396
397#else	/* __lint */
398
399#if defined(__amd64)
400
401	ENTRY(lock_set)
402	movb	$-1, %dl
403	xchgb	%dl, (%rdi)		/* try to set lock */
404	testb	%dl, %dl		/* did we get it? */
405	jnz	lock_set_spin		/* no, go to C for the hard case */
406.lock_set_lockstat_patch_point:
407	ret
408	movq	%rdi, %rsi		/* rsi = lock addr */
409	movq	%gs:CPU_THREAD, %rdx	/* rdx = thread addr */
410	movl	$LS_LOCK_SET_ACQUIRE, %edi
411	jmp	lockstat_wrapper
412	SET_SIZE(lock_set)
413
414#else
415
416	ENTRY(lock_set)
417	movl	4(%esp), %ecx		/* ecx = lock addr */
418	movl	$-1, %edx
419	xchgb	%dl, (%ecx)		/* try to set lock */
420	testb	%dl, %dl		/* did we get it? */
421	jnz	lock_set_spin		/* no, go to C for the hard case */
422.lock_set_lockstat_patch_point:
423	ret
424	movl	%gs:CPU_THREAD, %edx	/* edx = thread addr */
425	movl	$LS_LOCK_SET_ACQUIRE, %eax
426	jmp	lockstat_wrapper
427	SET_SIZE(lock_set)
428
429#endif	/* !__amd64 */
430
431#endif	/* __lint */
432
433/*
434 * lock_clear_splx(lp, s)
435 */
436
437#if defined(lint) || defined(__lint)
438
439/* ARGSUSED */
440void
441lock_clear_splx(lock_t *lp, int s)
442{}
443
444#else	/* __lint */
445
446#if defined(__amd64)
447
448	ENTRY(lock_clear_splx)
449	movb	$0, (%rdi)		/* clear lock */
450.lock_clear_splx_lockstat_patch_point:
451	jmp	0f
4520:
453	movl	%esi, %edi		/* arg for splx */
454	jmp	splx			/* let splx do its thing */
455.lock_clear_splx_lockstat:
456	pushq	%rbp			/* align stack properly */
457	movq	%rsp, %rbp
458	subq	$16, %rsp		/* space to save args across splx */
459	movq	%rdi, 8(%rsp)		/* save lock ptr across splx call */
460	movl	%esi, %edi		/* arg for splx */
461	call	splx			/* lower the priority */
462	movq	8(%rsp), %rsi		/* rsi = lock ptr */
463	leave				/* unwind stack */
464	movq	%gs:CPU_THREAD, %rdx	/* rdx = thread addr */
465	movl	$LS_LOCK_CLEAR_SPLX_RELEASE, %edi
466	jmp	lockstat_wrapper
467	SET_SIZE(lock_clear_splx)
468
469#else
470
471	ENTRY(lock_clear_splx)
472	movl	4(%esp), %eax		/* eax = lock addr */
473	movb	$0, (%eax)		/* clear lock */
474.lock_clear_splx_lockstat_patch_point:
475	jmp	0f
4760:
477	movl	8(%esp), %edx		/* edx = desired pil */
478	movl	%edx, 4(%esp)		/* set spl arg up for splx */
479	jmp	splx			/* let splx do it's thing */
480.lock_clear_splx_lockstat:
481	movl	8(%esp), %edx		/* edx = desired pil */
482	pushl	%ebp			/* set up stack frame */
483	movl	%esp, %ebp
484	pushl	%edx
485	call	splx
486	leave				/* unwind stack */
487	movl	4(%esp), %ecx		/* ecx = lock pointer */
488	movl	%gs:CPU_THREAD, %edx	/* edx = thread addr */
489	movl	$LS_LOCK_CLEAR_SPLX_RELEASE, %eax
490	jmp	lockstat_wrapper
491	SET_SIZE(lock_clear_splx)
492
493#endif	/* !__amd64 */
494
495#if defined(__GNUC_AS__)
496#define	LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL	\
497	(.lock_clear_splx_lockstat - .lock_clear_splx_lockstat_patch_point - 2)
498
499#define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT	\
500	(.lock_clear_splx_lockstat_patch_point + 1)
501#else
502#define	LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL	\
503	[.lock_clear_splx_lockstat - .lock_clear_splx_lockstat_patch_point - 2]
504
505#define LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT	\
506	[.lock_clear_splx_lockstat_patch_point + 1]
507#endif
508
509#endif	/* __lint */
510
511/*
512 * mutex_enter() and mutex_exit().
513 *
514 * These routines handle the simple cases of mutex_enter() (adaptive
515 * lock, not held) and mutex_exit() (adaptive lock, held, no waiters).
516 * If anything complicated is going on we punt to mutex_vector_enter().
517 *
518 * mutex_tryenter() is similar to mutex_enter() but returns zero if
519 * the lock cannot be acquired, nonzero on success.
520 *
521 * If mutex_exit() gets preempted in the window between checking waiters
522 * and clearing the lock, we can miss wakeups.  Disabling preemption
523 * in the mutex code is prohibitively expensive, so instead we detect
524 * mutex preemption by examining the trapped PC in the interrupt path.
525 * If we interrupt a thread in mutex_exit() that has not yet cleared
526 * the lock, cmnint() resets its PC back to the beginning of
527 * mutex_exit() so it will check again for waiters when it resumes.
528 *
529 * The lockstat code below is activated when the lockstat driver
530 * calls lockstat_hot_patch() to hot-patch the kernel mutex code.
531 * Note that we don't need to test lockstat_event_mask here -- we won't
532 * patch this code in unless we're gathering ADAPTIVE_HOLD lockstats.
533 */
534#if defined(lint) || defined(__lint)
535
536/* ARGSUSED */
537void
538mutex_enter(kmutex_t *lp)
539{}
540
541/* ARGSUSED */
542int
543mutex_tryenter(kmutex_t *lp)
544{ return (0); }
545
546/* ARGSUSED */
547int
548mutex_adaptive_tryenter(mutex_impl_t *lp)
549{ return (0); }
550
551/* ARGSUSED */
552void
553mutex_exit(kmutex_t *lp)
554{}
555
556#else
557
558#if defined(__amd64)
559
560	ENTRY_NP(mutex_enter)
561	movq	%gs:CPU_THREAD, %rdx		/* rdx = thread ptr */
562	xorl	%eax, %eax			/* rax = 0 (unheld adaptive) */
563	lock
564	cmpxchgq %rdx, (%rdi)
565	jnz	mutex_vector_enter
566.mutex_enter_lockstat_patch_point:
567#if defined(OPTERON_WORKAROUND_6323525)
568.mutex_enter_6323525_patch_point:
569	ret					/* nop space for lfence */
570	nop
571	nop
572.mutex_enter_lockstat_6323525_patch_point:	/* new patch point if lfence */
573	nop
574#else	/* OPTERON_WORKAROUND_6323525 */
575	ret
576#endif	/* OPTERON_WORKAROUND_6323525 */
577	movq	%rdi, %rsi
578	movl	$LS_MUTEX_ENTER_ACQUIRE, %edi
579/*
580 * expects %rdx=thread, %rsi=lock, %edi=lockstat event
581 */
582	ALTENTRY(lockstat_wrapper)
583	incb	T_LOCKSTAT(%rdx)		/* curthread->t_lockstat++ */
584	leaq	lockstat_probemap(%rip), %rax
585	movl	(%rax, %rdi, DTRACE_IDSIZE), %eax
586	testl	%eax, %eax			/* check for non-zero probe */
587	jz	1f
588	pushq	%rbp				/* align stack properly */
589	movq	%rsp, %rbp
590	movl	%eax, %edi
591	call	*lockstat_probe
592	leave					/* unwind stack */
5931:
594	movq	%gs:CPU_THREAD, %rdx		/* reload thread ptr */
595	decb	T_LOCKSTAT(%rdx)		/* curthread->t_lockstat-- */
596	movl	$1, %eax			/* return success if tryenter */
597	ret
598	SET_SIZE(lockstat_wrapper)
599	SET_SIZE(mutex_enter)
600
601/*
602 * expects %rcx=thread, %rdx=arg, %rsi=lock, %edi=lockstat event
603 */
604	ENTRY(lockstat_wrapper_arg)
605	incb	T_LOCKSTAT(%rcx)		/* curthread->t_lockstat++ */
606	leaq	lockstat_probemap(%rip), %rax
607	movl	(%rax, %rdi, DTRACE_IDSIZE), %eax
608	testl	%eax, %eax			/* check for non-zero probe */
609	jz	1f
610	pushq	%rbp				/* align stack properly */
611	movq	%rsp, %rbp
612	movl	%eax, %edi
613	call	*lockstat_probe
614	leave					/* unwind stack */
6151:
616	movq	%gs:CPU_THREAD, %rdx		/* reload thread ptr */
617	decb	T_LOCKSTAT(%rdx)		/* curthread->t_lockstat-- */
618	movl	$1, %eax			/* return success if tryenter */
619	ret
620	SET_SIZE(lockstat_wrapper_arg)
621
622
623	ENTRY(mutex_tryenter)
624	movq	%gs:CPU_THREAD, %rdx		/* rdx = thread ptr */
625	xorl	%eax, %eax			/* rax = 0 (unheld adaptive) */
626	lock
627	cmpxchgq %rdx, (%rdi)
628	jnz	mutex_vector_tryenter
629	not	%eax				/* return success (nonzero) */
630#if defined(OPTERON_WORKAROUND_6323525)
631.mutex_tryenter_lockstat_patch_point:
632.mutex_tryenter_6323525_patch_point:
633	ret					/* nop space for lfence */
634	nop
635	nop
636.mutex_tryenter_lockstat_6323525_patch_point:	/* new patch point if lfence */
637	nop
638#else	/* OPTERON_WORKAROUND_6323525 */
639.mutex_tryenter_lockstat_patch_point:
640	ret
641#endif	/* OPTERON_WORKAROUND_6323525 */
642	movq	%rdi, %rsi
643	movl	$LS_MUTEX_ENTER_ACQUIRE, %edi
644	jmp	lockstat_wrapper
645	SET_SIZE(mutex_tryenter)
646
647	ENTRY(mutex_adaptive_tryenter)
648	movq	%gs:CPU_THREAD, %rdx		/* rdx = thread ptr */
649	xorl	%eax, %eax			/* rax = 0 (unheld adaptive) */
650	lock
651	cmpxchgq %rdx, (%rdi)
652	jnz	0f
653	not	%eax				/* return success (nonzero) */
654#if defined(OPTERON_WORKAROUND_6323525)
655.mutex_atryenter_6323525_patch_point:
656	ret					/* nop space for lfence */
657	nop
658	nop
659	nop
660#else	/* OPTERON_WORKAROUND_6323525 */
661	ret
662#endif	/* OPTERON_WORKAROUND_6323525 */
6630:
664	xorl	%eax, %eax			/* return failure */
665	ret
666	SET_SIZE(mutex_adaptive_tryenter)
667
668	.globl	mutex_exit_critical_start
669
670	ENTRY(mutex_exit)
671mutex_exit_critical_start:		/* If interrupted, restart here */
672	movq	%gs:CPU_THREAD, %rdx
673	cmpq	%rdx, (%rdi)
674	jne	mutex_vector_exit		/* wrong type or wrong owner */
675	movq	$0, (%rdi)			/* clear owner AND lock */
676.mutex_exit_critical_end:
677.mutex_exit_lockstat_patch_point:
678	ret
679	movq	%rdi, %rsi
680	movl	$LS_MUTEX_EXIT_RELEASE, %edi
681	jmp	lockstat_wrapper
682	SET_SIZE(mutex_exit)
683
684	.globl	mutex_exit_critical_size
685	.type	mutex_exit_critical_size, @object
686	.align	CPTRSIZE
687mutex_exit_critical_size:
688	.quad	.mutex_exit_critical_end - mutex_exit_critical_start
689	SET_SIZE(mutex_exit_critical_size)
690
691#else
692
693	ENTRY_NP(mutex_enter)
694	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
695	movl	4(%esp), %ecx			/* ecx = lock ptr */
696	xorl	%eax, %eax			/* eax = 0 (unheld adaptive) */
697	lock
698	cmpxchgl %edx, (%ecx)
699	jnz	mutex_vector_enter
700#if defined(OPTERON_WORKAROUND_6323525)
701.mutex_enter_lockstat_patch_point:
702.mutex_enter_6323525_patch_point:
703	ret					/* nop space for lfence */
704	nop
705	nop
706.mutex_enter_lockstat_6323525_patch_point:	/* new patch point if lfence */
707	nop
708#else	/* OPTERON_WORKAROUND_6323525 */
709.mutex_enter_lockstat_patch_point:
710	ret
711#endif	/* OPTERON_WORKAROUND_6323525 */
712	movl	$LS_MUTEX_ENTER_ACQUIRE, %eax
713	ALTENTRY(lockstat_wrapper)	/* expects edx=thread, ecx=lock, */
714					/*   eax=lockstat event */
715	pushl	%ebp				/* buy a frame */
716	movl	%esp, %ebp
717	incb	T_LOCKSTAT(%edx)		/* curthread->t_lockstat++ */
718	pushl	%edx				/* save thread pointer	 */
719	movl	$lockstat_probemap, %edx
720	movl	(%edx, %eax, DTRACE_IDSIZE), %eax
721	testl	%eax, %eax			/* check for non-zero probe */
722	jz	1f
723	pushl	%ecx				/* push lock */
724	pushl	%eax				/* push probe ID */
725	call	*lockstat_probe
726	addl	$8, %esp
7271:
728	popl	%edx				/* restore thread pointer */
729	decb	T_LOCKSTAT(%edx)		/* curthread->t_lockstat-- */
730	movl	$1, %eax			/* return success if tryenter */
731	popl	%ebp				/* pop off frame */
732	ret
733	SET_SIZE(lockstat_wrapper)
734	SET_SIZE(mutex_enter)
735
736	ENTRY(lockstat_wrapper_arg)	/* expects edx=thread, ecx=lock, */
737					/* eax=lockstat event, pushed arg */
738	incb	T_LOCKSTAT(%edx)		/* curthread->t_lockstat++ */
739	pushl	%edx				/* save thread pointer	 */
740	movl	$lockstat_probemap, %edx
741	movl	(%edx, %eax, DTRACE_IDSIZE), %eax
742	testl	%eax, %eax			/* check for non-zero probe */
743	jz	1f
744	pushl	%ebp				/* save %ebp */
745	pushl	8(%esp)				/* push arg1 */
746	movl	%ebp, 12(%esp)			/* fake up the stack frame */
747	movl	%esp, %ebp			/* fake up base pointer */
748	addl	$12, %ebp			/* adjust faked base pointer */
749	pushl	%ecx				/* push lock */
750	pushl	%eax				/* push probe ID */
751	call	*lockstat_probe
752	addl	$12, %esp			/* adjust for arguments */
753	popl	%ebp				/* pop frame */
7541:
755	popl	%edx				/* restore thread pointer */
756	decb	T_LOCKSTAT(%edx)		/* curthread->t_lockstat-- */
757	movl	$1, %eax			/* return success if tryenter */
758	addl	$4, %esp			/* pop argument */
759	ret
760	SET_SIZE(lockstat_wrapper_arg)
761
762
763	ENTRY(mutex_tryenter)
764	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
765	movl	4(%esp), %ecx			/* ecx = lock ptr */
766	xorl	%eax, %eax			/* eax = 0 (unheld adaptive) */
767	lock
768	cmpxchgl %edx, (%ecx)
769	jnz	mutex_vector_tryenter
770	movl	%ecx, %eax
771#if defined(OPTERON_WORKAROUND_6323525)
772.mutex_tryenter_lockstat_patch_point:
773.mutex_tryenter_6323525_patch_point:
774	ret					/* nop space for lfence */
775	nop
776	nop
777.mutex_tryenter_lockstat_6323525_patch_point:	/* new patch point if lfence */
778	nop
779#else	/* OPTERON_WORKAROUND_6323525 */
780.mutex_tryenter_lockstat_patch_point:
781	ret
782#endif	/* OPTERON_WORKAROUND_6323525 */
783	movl	$LS_MUTEX_ENTER_ACQUIRE, %eax
784	jmp	lockstat_wrapper
785	SET_SIZE(mutex_tryenter)
786
787	ENTRY(mutex_adaptive_tryenter)
788	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
789	movl	4(%esp), %ecx			/* ecx = lock ptr */
790	xorl	%eax, %eax			/* eax = 0 (unheld adaptive) */
791	lock
792	cmpxchgl %edx, (%ecx)
793	jnz	0f
794	movl	%ecx, %eax
795#if defined(OPTERON_WORKAROUND_6323525)
796.mutex_atryenter_6323525_patch_point:
797	ret					/* nop space for lfence */
798	nop
799	nop
800	nop
801#else	/* OPTERON_WORKAROUND_6323525 */
802	ret
803#endif	/* OPTERON_WORKAROUND_6323525 */
8040:
805	xorl	%eax, %eax
806	ret
807	SET_SIZE(mutex_adaptive_tryenter)
808
809	.globl	mutex_exit_critical_size
810	.globl	mutex_exit_critical_start
811
812	ENTRY(mutex_exit)
813mutex_exit_critical_start:		/* If interrupted, restart here */
814	movl	%gs:CPU_THREAD, %edx
815	movl	4(%esp), %ecx
816	cmpl	%edx, (%ecx)
817	jne	mutex_vector_exit		/* wrong type or wrong owner */
818	movl	$0, (%ecx)			/* clear owner AND lock */
819.mutex_exit_critical_end:
820.mutex_exit_lockstat_patch_point:
821	ret
822	movl	$LS_MUTEX_EXIT_RELEASE, %eax
823	jmp	lockstat_wrapper
824	SET_SIZE(mutex_exit)
825
826	.globl	mutex_exit_critical_size
827	.type	mutex_exit_critical_size, @object
828	.align	CPTRSIZE
829mutex_exit_critical_size:
830	.long	.mutex_exit_critical_end - mutex_exit_critical_start
831	SET_SIZE(mutex_exit_critical_size)
832
833#endif	/* !__amd64 */
834
835#endif	/* __lint */
836
837/*
838 * rw_enter() and rw_exit().
839 *
840 * These routines handle the simple cases of rw_enter (write-locking an unheld
841 * lock or read-locking a lock that's neither write-locked nor write-wanted)
842 * and rw_exit (no waiters or not the last reader).  If anything complicated
843 * is going on we punt to rw_enter_sleep() and rw_exit_wakeup(), respectively.
844 */
845#if defined(lint) || defined(__lint)
846
847/* ARGSUSED */
848void
849rw_enter(krwlock_t *lp, krw_t rw)
850{}
851
852/* ARGSUSED */
853void
854rw_exit(krwlock_t *lp)
855{}
856
857#else	/* __lint */
858
859#if defined(__amd64)
860
861	ENTRY(rw_enter)
862	movq	%gs:CPU_THREAD, %rdx		/* rdx = thread ptr */
863	cmpl	$RW_WRITER, %esi
864	je	.rw_write_enter
865	incl	T_KPRI_REQ(%rdx)		/* THREAD_KPRI_REQUEST() */
866	movq	(%rdi), %rax			/* rax = old rw_wwwh value */
867	testl	$RW_WRITE_LOCKED|RW_WRITE_WANTED, %eax
868	jnz	rw_enter_sleep
869	leaq	RW_READ_LOCK(%rax), %rdx	/* rdx = new rw_wwwh value */
870	lock
871	cmpxchgq %rdx, (%rdi)			/* try to grab read lock */
872	jnz	rw_enter_sleep
873.rw_read_enter_lockstat_patch_point:
874	ret
875	movq	%gs:CPU_THREAD, %rcx		/* rcx = thread ptr */
876	movq	%rdi, %rsi			/* rsi = lock ptr */
877	movl	$LS_RW_ENTER_ACQUIRE, %edi
878	movl	$RW_READER, %edx
879	jmp	lockstat_wrapper_arg
880.rw_write_enter:
881	orq	$RW_WRITE_LOCKED, %rdx		/* rdx = write-locked value */
882	xorl	%eax, %eax			/* rax = unheld value */
883	lock
884	cmpxchgq %rdx, (%rdi)			/* try to grab write lock */
885	jnz	rw_enter_sleep
886
887#if defined(OPTERON_WORKAROUND_6323525)
888.rw_write_enter_lockstat_patch_point:
889.rw_write_enter_6323525_patch_point:
890	ret
891	nop
892	nop
893.rw_write_enter_lockstat_6323525_patch_point:
894	nop
895#else	/* OPTERON_WORKAROUND_6323525 */
896.rw_write_enter_lockstat_patch_point:
897	ret
898#endif	/* OPTERON_WORKAROUND_6323525 */
899
900	movq	%gs:CPU_THREAD, %rcx		/* rcx = thread ptr */
901	movq	%rdi, %rsi			/* rsi = lock ptr */
902	movl	$LS_RW_ENTER_ACQUIRE, %edi
903	movl	$RW_WRITER, %edx
904	jmp	lockstat_wrapper_arg
905	SET_SIZE(rw_enter)
906
907	ENTRY(rw_exit)
908	movq	(%rdi), %rax			/* rax = old rw_wwwh value */
909	cmpl	$RW_READ_LOCK, %eax		/* single-reader, no waiters? */
910	jne	.rw_not_single_reader
911	xorl	%edx, %edx			/* rdx = new value (unheld) */
912.rw_read_exit:
913	lock
914	cmpxchgq %rdx, (%rdi)			/* try to drop read lock */
915	jnz	rw_exit_wakeup
916	movq	%gs:CPU_THREAD, %rcx		/* rcx = thread ptr */
917	decl	T_KPRI_REQ(%rcx)		/* THREAD_KPRI_RELEASE() */
918.rw_read_exit_lockstat_patch_point:
919	ret
920	movq	%rdi, %rsi			/* rsi = lock ptr */
921	movl	$LS_RW_EXIT_RELEASE, %edi
922	movl	$RW_READER, %edx
923	jmp	lockstat_wrapper_arg
924.rw_not_single_reader:
925	testl	$RW_WRITE_LOCKED, %eax	/* write-locked or write-wanted? */
926	jnz	.rw_write_exit
927	leaq	-RW_READ_LOCK(%rax), %rdx	/* rdx = new value */
928	cmpl	$RW_READ_LOCK, %edx
929	jge	.rw_read_exit		/* not last reader, safe to drop */
930	jmp	rw_exit_wakeup			/* last reader with waiters */
931.rw_write_exit:
932	movq	%gs:CPU_THREAD, %rax		/* rax = thread ptr */
933	xorl	%edx, %edx			/* rdx = new value (unheld) */
934	orq	$RW_WRITE_LOCKED, %rax		/* eax = write-locked value */
935	lock
936	cmpxchgq %rdx, (%rdi)			/* try to drop read lock */
937	jnz	rw_exit_wakeup
938.rw_write_exit_lockstat_patch_point:
939	ret
940	movq	%gs:CPU_THREAD, %rcx		/* rcx = thread ptr */
941	movq	%rdi, %rsi			/* rsi - lock ptr */
942	movl	$LS_RW_EXIT_RELEASE, %edi
943	movl	$RW_WRITER, %edx
944	jmp	lockstat_wrapper_arg
945	SET_SIZE(rw_exit)
946
947#else
948
949	ENTRY(rw_enter)
950	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
951	movl	4(%esp), %ecx			/* ecx = lock ptr */
952	cmpl	$RW_WRITER, 8(%esp)
953	je	.rw_write_enter
954	incl	T_KPRI_REQ(%edx)		/* THREAD_KPRI_REQUEST() */
955	movl	(%ecx), %eax			/* eax = old rw_wwwh value */
956	testl	$RW_WRITE_LOCKED|RW_WRITE_WANTED, %eax
957	jnz	rw_enter_sleep
958	leal	RW_READ_LOCK(%eax), %edx	/* edx = new rw_wwwh value */
959	lock
960	cmpxchgl %edx, (%ecx)			/* try to grab read lock */
961	jnz	rw_enter_sleep
962.rw_read_enter_lockstat_patch_point:
963	ret
964	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
965	movl	$LS_RW_ENTER_ACQUIRE, %eax
966	pushl	$RW_READER
967	jmp	lockstat_wrapper_arg
968.rw_write_enter:
969	orl	$RW_WRITE_LOCKED, %edx		/* edx = write-locked value */
970	xorl	%eax, %eax			/* eax = unheld value */
971	lock
972	cmpxchgl %edx, (%ecx)			/* try to grab write lock */
973	jnz	rw_enter_sleep
974
975#if defined(OPTERON_WORKAROUND_6323525)
976.rw_write_enter_lockstat_patch_point:
977.rw_write_enter_6323525_patch_point:
978	ret
979	nop
980	nop
981.rw_write_enter_lockstat_6323525_patch_point:
982	nop
983#else	/* OPTERON_WORKAROUND_6323525 */
984.rw_write_enter_lockstat_patch_point:
985	ret
986#endif	/* OPTERON_WORKAROUND_6323525 */
987
988	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
989	movl	$LS_RW_ENTER_ACQUIRE, %eax
990	pushl	$RW_WRITER
991	jmp	lockstat_wrapper_arg
992	SET_SIZE(rw_enter)
993
994	ENTRY(rw_exit)
995	movl	4(%esp), %ecx			/* ecx = lock ptr */
996	movl	(%ecx), %eax			/* eax = old rw_wwwh value */
997	cmpl	$RW_READ_LOCK, %eax		/* single-reader, no waiters? */
998	jne	.rw_not_single_reader
999	xorl	%edx, %edx			/* edx = new value (unheld) */
1000.rw_read_exit:
1001	lock
1002	cmpxchgl %edx, (%ecx)			/* try to drop read lock */
1003	jnz	rw_exit_wakeup
1004	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
1005	decl	T_KPRI_REQ(%edx)		/* THREAD_KPRI_RELEASE() */
1006.rw_read_exit_lockstat_patch_point:
1007	ret
1008	movl	$LS_RW_EXIT_RELEASE, %eax
1009	pushl	$RW_READER
1010	jmp	lockstat_wrapper_arg
1011.rw_not_single_reader:
1012	testl	$RW_WRITE_LOCKED, %eax	/* write-locked or write-wanted? */
1013	jnz	.rw_write_exit
1014	leal	-RW_READ_LOCK(%eax), %edx	/* edx = new value */
1015	cmpl	$RW_READ_LOCK, %edx
1016	jge	.rw_read_exit		/* not last reader, safe to drop */
1017	jmp	rw_exit_wakeup			/* last reader with waiters */
1018.rw_write_exit:
1019	movl	%gs:CPU_THREAD, %eax		/* eax = thread ptr */
1020	xorl	%edx, %edx			/* edx = new value (unheld) */
1021	orl	$RW_WRITE_LOCKED, %eax		/* eax = write-locked value */
1022	lock
1023	cmpxchgl %edx, (%ecx)			/* try to drop read lock */
1024	jnz	rw_exit_wakeup
1025.rw_write_exit_lockstat_patch_point:
1026	ret
1027	movl	%gs:CPU_THREAD, %edx		/* edx = thread ptr */
1028	movl	$LS_RW_EXIT_RELEASE, %eax
1029	pushl	$RW_WRITER
1030	jmp	lockstat_wrapper_arg
1031	SET_SIZE(rw_exit)
1032
1033#endif	/* !__amd64 */
1034
1035#endif	/* __lint */
1036
1037#if defined(OPTERON_WORKAROUND_6323525)
1038#if defined(lint) || defined(__lint)
1039
1040int	workaround_6323525_patched;
1041
1042void
1043patch_workaround_6323525(void)
1044{}
1045
1046#else	/* lint */
1047
1048/*
1049 * If it is necessary to patch the lock enter routines with the lfence
1050 * workaround, workaround_6323525_patched is set to a non-zero value so that
1051 * the lockstat_hat_patch routine can patch to the new location of the 'ret'
1052 * instruction.
1053 */
1054	DGDEF3(workaround_6323525_patched, 4, 4)
1055	.long	0
1056
1057#if defined(__amd64)
1058
1059#define HOT_MUTEX_PATCH(srcaddr, dstaddr, size)	\
1060	movq	$size, %rbx;			\
1061	movq	$dstaddr, %r13;			\
1062	addq	%rbx, %r13;			\
1063	movq	$srcaddr, %r12;			\
1064	addq	%rbx, %r12;			\
10650:						\
1066	decq	%r13;				\
1067	decq	%r12;				\
1068	movzbl	(%r12), %esi;			\
1069	movq	$1, %rdx;			\
1070	movq	%r13, %rdi;			\
1071	call	hot_patch_kernel_text;		\
1072	decq	%rbx;				\
1073	testq	%rbx, %rbx;			\
1074	jg	0b;
1075
1076/*
1077 * patch_workaround_6323525: provide workaround for 6323525
1078 *
1079 * The workaround is to place a fencing instruction (lfence) between the
1080 * mutex operation and the subsequent read-modify-write instruction.
1081 *
1082 * This routine hot patches the lfence instruction on top of the space
1083 * reserved by nops in the lock enter routines.
1084 */
1085	ENTRY_NP(patch_workaround_6323525)
1086	pushq	%rbp
1087	movq	%rsp, %rbp
1088	pushq	%r12
1089	pushq	%r13
1090	pushq	%rbx
1091
1092	/*
1093	 * lockstat_hot_patch() to use the alternate lockstat workaround
1094	 * 6323525 patch points (points past the lfence instruction to the
1095	 * new ret) when workaround_6323525_patched is set.
1096	 */
1097	movl	$1, workaround_6323525_patched
1098
1099	/*
1100	 * patch ret/nop/nop/nop to lfence/ret at the end of the lock enter
1101	 * routines. The 4 bytes are patched in reverse order so that the
1102	 * the existing ret is overwritten last. This provides lock enter
1103	 * sanity during the intermediate patching stages.
1104	 */
1105	HOT_MUTEX_PATCH(_lfence_insn, .mutex_enter_6323525_patch_point, 4)
1106	HOT_MUTEX_PATCH(_lfence_insn, .mutex_tryenter_6323525_patch_point, 4)
1107	HOT_MUTEX_PATCH(_lfence_insn, .mutex_atryenter_6323525_patch_point, 4)
1108	HOT_MUTEX_PATCH(_lfence_insn, .rw_write_enter_6323525_patch_point, 4)
1109
1110	popq	%rbx
1111	popq	%r13
1112	popq	%r12
1113	movq	%rbp, %rsp
1114	popq	%rbp
1115	ret
1116_lfence_insn:
1117	lfence
1118	ret
1119	SET_SIZE(patch_workaround_6323525)
1120
1121
1122#else	/* __amd64 */
1123
1124#define HOT_MUTEX_PATCH(srcaddr, dstaddr, size)	\
1125	movl	$size, %ebx;			\
1126	movl	$srcaddr, %esi;			\
1127	addl	%ebx, %esi;			\
1128	movl	$dstaddr, %edi;			\
1129	addl	%ebx, %edi;			\
11300:      					\
1131	decl	%esi;				\
1132	decl	%edi;				\
1133	pushl	$1;				\
1134	movzbl	(%esi), %eax;			\
1135	pushl	%eax;				\
1136	pushl	%edi;				\
1137	call	hot_patch_kernel_text;		\
1138	addl	$12, %esp;			\
1139	decl	%ebx;				\
1140	testl	%ebx, %ebx;			\
1141	jg	0b;
1142
1143
1144	/* see comments above */
1145	ENTRY_NP(patch_workaround_6323525)
1146	pushl	%ebp
1147	movl	%esp, %ebp
1148	pushl	%ebx
1149	pushl	%esi
1150	pushl	%edi
1151
1152	movl	$1, workaround_6323525_patched
1153
1154	HOT_MUTEX_PATCH(_lfence_insn, .mutex_enter_6323525_patch_point, 4)
1155	HOT_MUTEX_PATCH(_lfence_insn, .mutex_tryenter_6323525_patch_point, 4)
1156	HOT_MUTEX_PATCH(_lfence_insn, .mutex_atryenter_6323525_patch_point, 4)
1157	HOT_MUTEX_PATCH(_lfence_insn, .rw_write_enter_6323525_patch_point, 4)
1158
1159	popl	%edi
1160	popl	%esi
1161	popl	%ebx
1162	movl	%ebp, %esp
1163	popl	%ebp
1164	ret
1165_lfence_insn:
1166	.byte	0xf, 0xae, 0xe8		/ [lfence instruction]
1167	ret
1168	SET_SIZE(patch_workaround_6323525)
1169
1170#endif	/* !__amd64 */
1171#endif	/* !lint */
1172#endif	/* OPTERON_WORKAROUND_6323525 */
1173
1174
1175#if defined(lint) || defined(__lint)
1176
1177void
1178lockstat_hot_patch(void)
1179{}
1180
1181#else
1182
1183#if defined(__amd64)
1184
1185#define	HOT_PATCH(addr, event, active_instr, normal_instr, len)	\
1186	movq	$normal_instr, %rsi;		\
1187	movq	$active_instr, %rdi;		\
1188	leaq	lockstat_probemap(%rip), %rax;	\
1189	movl 	_MUL(event, DTRACE_IDSIZE)(%rax), %eax;	\
1190	testl	%eax, %eax;			\
1191	jz	9f;				\
1192	movq	%rdi, %rsi;			\
11939:						\
1194	movq	$len, %rdx;			\
1195	movq	$addr, %rdi;			\
1196	call	hot_patch_kernel_text
1197
1198#else
1199
1200#define	HOT_PATCH(addr, event, active_instr, normal_instr, len)	\
1201	movl	$normal_instr, %ecx;		\
1202	movl	$active_instr, %edx;		\
1203	movl	$lockstat_probemap, %eax;	\
1204	movl	_MUL(event, DTRACE_IDSIZE)(%eax), %eax;	\
1205	testl	%eax, %eax;			\
1206	jz	. + 4;				\
1207	movl	%edx, %ecx;			\
1208	pushl	$len;				\
1209	pushl	%ecx;				\
1210	pushl	$addr;				\
1211	call	hot_patch_kernel_text;		\
1212	addl	$12, %esp;
1213
1214#endif	/* !__amd64 */
1215
1216	ENTRY(lockstat_hot_patch)
1217#if defined(__amd64)
1218	pushq	%rbp			/* align stack properly */
1219	movq	%rsp, %rbp
1220#endif	/* __amd64 */
1221
1222#if defined(OPTERON_WORKAROUND_6323525)
1223	cmpl	$0, workaround_6323525_patched
1224	je	1f
1225	HOT_PATCH(.mutex_enter_lockstat_6323525_patch_point,
1226		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1227	HOT_PATCH(.mutex_tryenter_lockstat_6323525_patch_point,
1228		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1229	HOT_PATCH(.rw_write_enter_lockstat_6323525_patch_point,
1230		LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1231	jmp	2f
12321:
1233	HOT_PATCH(.mutex_enter_lockstat_patch_point,
1234		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1235	HOT_PATCH(.mutex_tryenter_lockstat_patch_point,
1236		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1237	HOT_PATCH(.rw_write_enter_lockstat_patch_point,
1238		LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
12392:
1240#else	/* OPTERON_WORKAROUND_6323525 */
1241	HOT_PATCH(.mutex_enter_lockstat_patch_point,
1242		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1243	HOT_PATCH(.mutex_tryenter_lockstat_patch_point,
1244		LS_MUTEX_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1245	HOT_PATCH(.rw_write_enter_lockstat_patch_point,
1246		LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1247#endif	/* !OPTERON_WORKAROUND_6323525 */
1248	HOT_PATCH(.mutex_exit_lockstat_patch_point,
1249		LS_MUTEX_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1)
1250	HOT_PATCH(.rw_read_enter_lockstat_patch_point,
1251		LS_RW_ENTER_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1252	HOT_PATCH(.rw_write_exit_lockstat_patch_point,
1253		LS_RW_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1)
1254	HOT_PATCH(.rw_read_exit_lockstat_patch_point,
1255		LS_RW_EXIT_RELEASE, NOP_INSTR, RET_INSTR, 1)
1256	HOT_PATCH(.lock_set_lockstat_patch_point,
1257		LS_LOCK_SET_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1258	HOT_PATCH(.lock_try_lockstat_patch_point,
1259		LS_LOCK_TRY_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1260	HOT_PATCH(.lock_clear_lockstat_patch_point,
1261		LS_LOCK_CLEAR_RELEASE, NOP_INSTR, RET_INSTR, 1)
1262	HOT_PATCH(.lock_set_spl_lockstat_patch_point,
1263		LS_LOCK_SET_SPL_ACQUIRE, NOP_INSTR, RET_INSTR, 1)
1264
1265	HOT_PATCH(LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_POINT,
1266		LS_LOCK_CLEAR_SPLX_RELEASE,
1267		LOCK_CLEAR_SPLX_LOCKSTAT_PATCH_VAL, 0, 1);
1268#if defined(__amd64)
1269	leave			/* unwind stack */
1270#endif	/* __amd64 */
1271	ret
1272	SET_SIZE(lockstat_hot_patch)
1273
1274#endif	/* __lint */
1275
1276#if defined(lint) || defined(__lint)
1277
1278/* XX64 membar_*() should be inlines */
1279
1280void
1281membar_sync(void)
1282{}
1283
1284void
1285membar_enter(void)
1286{}
1287
1288void
1289membar_exit(void)
1290{}
1291
1292void
1293membar_producer(void)
1294{}
1295
1296void
1297membar_consumer(void)
1298{}
1299
1300#else	/* __lint */
1301
1302#if defined(__amd64)
1303
1304	ENTRY(membar_enter)
1305	ALTENTRY(membar_exit)
1306	ALTENTRY(membar_sync)
1307	mfence			/* lighter weight than lock; xorq $0,(%rsp) */
1308	ret
1309	SET_SIZE(membar_sync)
1310	SET_SIZE(membar_exit)
1311	SET_SIZE(membar_enter)
1312
1313	ENTRY(membar_producer)
1314	sfence
1315	ret
1316	SET_SIZE(membar_producer)
1317
1318	ENTRY(membar_consumer)
1319	lfence
1320	ret
1321	SET_SIZE(membar_consumer)
1322
1323#else
1324
1325	ENTRY(membar_enter)
1326	ALTENTRY(membar_exit)
1327	ALTENTRY(membar_sync)
1328	lock
1329	xorl	$0, (%esp)
1330	ret
1331	SET_SIZE(membar_sync)
1332	SET_SIZE(membar_exit)
1333	SET_SIZE(membar_enter)
1334
1335/*
1336 * On machines that support sfence and lfence, these
1337 * memory barriers can be more precisely implemented
1338 * without causing the whole world to stop
1339 */
1340	ENTRY(membar_producer)
1341	.globl	_patch_sfence_ret
1342_patch_sfence_ret:			/* c.f. membar #StoreStore */
1343	lock
1344	xorl	$0, (%esp)
1345	ret
1346	SET_SIZE(membar_producer)
1347
1348	ENTRY(membar_consumer)
1349	.globl	_patch_lfence_ret
1350_patch_lfence_ret:			/* c.f. membar #LoadLoad */
1351	lock
1352	xorl	$0, (%esp)
1353	ret
1354	SET_SIZE(membar_consumer)
1355
1356#endif	/* !__amd64 */
1357
1358#endif	/* __lint */
1359
1360/*
1361 * thread_onproc()
1362 * Set thread in onproc state for the specified CPU.
1363 * Also set the thread lock pointer to the CPU's onproc lock.
1364 * Since the new lock isn't held, the store ordering is important.
1365 * If not done in assembler, the compiler could reorder the stores.
1366 */
1367#if defined(lint) || defined(__lint)
1368
1369void
1370thread_onproc(kthread_id_t t, cpu_t *cp)
1371{
1372	t->t_state = TS_ONPROC;
1373	t->t_lockp = &cp->cpu_thread_lock;
1374}
1375
1376#else	/* __lint */
1377
1378#if defined(__amd64)
1379
1380	ENTRY(thread_onproc)
1381	addq	$CPU_THREAD_LOCK, %rsi	/* pointer to disp_lock while running */
1382	movl	$ONPROC_THREAD, T_STATE(%rdi)	/* set state to TS_ONPROC */
1383	movq	%rsi, T_LOCKP(%rdi)	/* store new lock pointer */
1384	ret
1385	SET_SIZE(thread_onproc)
1386
1387#else
1388
1389	ENTRY(thread_onproc)
1390	movl	4(%esp), %eax
1391	movl	8(%esp), %ecx
1392	addl	$CPU_THREAD_LOCK, %ecx	/* pointer to disp_lock while running */
1393	movl	$ONPROC_THREAD, T_STATE(%eax)	/* set state to TS_ONPROC */
1394	movl	%ecx, T_LOCKP(%eax)	/* store new lock pointer */
1395	ret
1396	SET_SIZE(thread_onproc)
1397
1398#endif	/* !__amd64 */
1399
1400#endif	/* __lint */
1401