xref: /freebsd/sys/i386/include/counter.h (revision 55bce0c1203e70d8b62a3dedc9235ab39660c6f4)
1 /*-
2  * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef __MACHINE_COUNTER_H__
30 #define __MACHINE_COUNTER_H__
31 
32 #include <sys/pcpu.h>
33 #ifdef INVARIANTS
34 #include <sys/proc.h>
35 #endif
36 #include <machine/md_var.h>
37 #include <machine/specialreg.h>
38 
39 #define	counter_enter()	do {				\
40 	if ((cpu_feature & CPUID_CX8) == 0)		\
41 		critical_enter();			\
42 } while (0)
43 
44 #define	counter_exit()	do {				\
45 	if ((cpu_feature & CPUID_CX8) == 0)		\
46 		critical_exit();			\
47 } while (0)
48 
49 extern struct pcpu __pcpu[MAXCPU];
50 
51 static inline void
52 counter_64_inc_8b(uint64_t *p, int64_t inc)
53 {
54 
55 	__asm __volatile(
56 	"movl	%%fs:(%%esi),%%eax\n\t"
57 	"movl	%%fs:4(%%esi),%%edx\n"
58 "1:\n\t"
59 	"movl	%%eax,%%ebx\n\t"
60 	"movl	%%edx,%%ecx\n\t"
61 	"addl	(%%edi),%%ebx\n\t"
62 	"adcl	4(%%edi),%%ecx\n\t"
63 	"cmpxchg8b %%fs:(%%esi)\n\t"
64 	"jnz	1b"
65 	:
66 	: "S" ((char *)p - (char *)&__pcpu[0]), "D" (&inc)
67 	: "memory", "cc", "eax", "edx", "ebx", "ecx");
68 }
69 
70 #define	counter_u64_add_protected(c, inc)	do {	\
71 	if ((cpu_feature & CPUID_CX8) == 0) {		\
72 		CRITICAL_ASSERT(curthread);		\
73 		*(uint64_t *)zpcpu_get(c) += (inc);	\
74 	} else						\
75 		counter_64_inc_8b((c), (inc));		\
76 } while (0)
77 
78 static inline void
79 counter_u64_add(counter_u64_t c, int64_t inc)
80 {
81 
82 	if ((cpu_feature & CPUID_CX8) == 0) {
83 		critical_enter();
84 		*(uint64_t *)zpcpu_get(c) += inc;
85 		critical_exit();
86 	} else {
87 		counter_64_inc_8b(c, inc);
88 	}
89 }
90 
91 #endif	/* ! __MACHINE_COUNTER_H__ */
92