summaryrefslogtreecommitdiff
path: root/arch/arm64/include/asm/percpu.h
blob: 09da25bc596fd0bdccdf03e94b37a4c81e0cc633 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
/*
 * Copyright (C) 2013 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __ASM_PERCPU_H
#define __ASM_PERCPU_H

#ifdef CONFIG_SMP

static inline void set_my_cpu_offset(unsigned long off)
{
	asm volatile("msr tpidr_el1, %0" :: "r" (off) : "memory");
}

static inline unsigned long __my_cpu_offset(void)
{
	unsigned long off;

	/*
	 * We want to allow caching the value, so avoid using volatile and
	 * instead use a fake stack read to hazard against barrier().
	 */
	asm("mrs %0, tpidr_el1" : "=r" (off) :
		"Q" (*(const unsigned long *)current_stack_pointer));

	return off;
}
#define __my_cpu_offset __my_cpu_offset()

#else	/* !CONFIG_SMP */

#define set_my_cpu_offset(x)	do { } while (0)

#endif /* CONFIG_SMP */

#define PERCPU_OP(op, asm_op)						\
static inline unsigned long __percpu_##op(void *ptr,			\
			unsigned long val, int size)			\
{									\
	unsigned long loop, ret;					\
									\
	switch (size) {							\
	case 1:								\
		do {							\
			asm ("//__per_cpu_" #op "_1\n"			\
			"ldxrb	  %w[ret], %[ptr]\n"			\
			#asm_op " %w[ret], %w[ret], %w[val]\n"		\
			"stxrb	  %w[loop], %w[ret], %[ptr]\n"		\
			: [loop] "=&r" (loop), [ret] "=&r" (ret),	\
			  [ptr] "+Q"(*(u8 *)ptr)			\
			: [val] "Ir" (val));				\
		} while (loop);						\
		break;							\
	case 2:								\
		do {							\
			asm ("//__per_cpu_" #op "_2\n"			\
			"ldxrh	  %w[ret], %[ptr]\n"			\
			#asm_op " %w[ret], %w[ret], %w[val]\n"		\
			"stxrh	  %w[loop], %w[ret], %[ptr]\n"		\
			: [loop] "=&r" (loop), [ret] "=&r" (ret),	\
			  [ptr]  "+Q"(*(u16 *)ptr)			\
			: [val] "Ir" (val));				\
		} while (loop);						\
		break;							\
	case 4:								\
		do {							\
			asm ("//__per_cpu_" #op "_4\n"			\
			"ldxr	  %w[ret], %[ptr]\n"			\
			#asm_op " %w[ret], %w[ret], %w[val]\n"		\
			"stxr	  %w[loop], %w[ret], %[ptr]\n"		\
			: [loop] "=&r" (loop), [ret] "=&r" (ret),	\
			  [ptr] "+Q"(*(u32 *)ptr)			\
			: [val] "Ir" (val));				\
		} while (loop);						\
		break;							\
	case 8:								\
		do {							\
			asm ("//__per_cpu_" #op "_8\n"			\
			"ldxr	  %[ret], %[ptr]\n"			\
			#asm_op " %[ret], %[ret], %[val]\n"		\
			"stxr	  %w[loop], %[ret], %[ptr]\n"		\
			: [loop] "=&r" (loop), [ret] "=&r" (ret),	\
			  [ptr] "+Q"(*(u64 *)ptr)			\
			: [val] "Ir" (val));				\
		} while (loop);						\
		break;							\
	default:							\
		BUILD_BUG();						\
	}								\
									\
	return ret;							\
}

PERCPU_OP(add, add)
PERCPU_OP(and, and)
PERCPU_OP(or, orr)
#undef PERCPU_OP

static inline unsigned long __percpu_read(void *ptr, int size)
{
	unsigned long ret;

	switch (size) {
	case 1:
		ret = ACCESS_ONCE(*(u8 *)ptr);
		break;
	case 2:
		ret = ACCESS_ONCE(*(u16 *)ptr);
		break;
	case 4:
		ret = ACCESS_ONCE(*(u32 *)ptr);
		break;
	case 8:
		ret = ACCESS_ONCE(*(u64 *)ptr);
		break;
	default:
		BUILD_BUG();
	}

	return ret;
}

static inline void __percpu_write(void *ptr, unsigned long val, int size)
{
	switch (size) {
	case 1:
		ACCESS_ONCE(*(u8 *)ptr) = (u8)val;
		break;
	case 2:
		ACCESS_ONCE(*(u16 *)ptr) = (u16)val;
		break;
	case 4:
		ACCESS_ONCE(*(u32 *)ptr) = (u32)val;
		break;
	case 8:
		ACCESS_ONCE(*(u64 *)ptr) = (u64)val;
		break;
	default:
		BUILD_BUG();
	}
}

static inline unsigned long __percpu_xchg(void *ptr, unsigned long val,
						int size)
{
	unsigned long ret, loop;

	switch (size) {
	case 1:
		do {
			asm ("//__percpu_xchg_1\n"
			"ldxrb %w[ret], %[ptr]\n"
			"stxrb %w[loop], %w[val], %[ptr]\n"
			: [loop] "=&r"(loop), [ret] "=&r"(ret),
			  [ptr] "+Q"(*(u8 *)ptr)
			: [val] "r" (val));
		} while (loop);
		break;
	case 2:
		do {
			asm ("//__percpu_xchg_2\n"
			"ldxrh %w[ret], %[ptr]\n"
			"stxrh %w[loop], %w[val], %[ptr]\n"
			: [loop] "=&r"(loop), [ret] "=&r"(ret),
			  [ptr] "+Q"(*(u16 *)ptr)
			: [val] "r" (val));
		} while (loop);
		break;
	case 4:
		do {
			asm ("//__percpu_xchg_4\n"
			"ldxr %w[ret], %[ptr]\n"
			"stxr %w[loop], %w[val], %[ptr]\n"
			: [loop] "=&r"(loop), [ret] "=&r"(ret),
			  [ptr] "+Q"(*(u32 *)ptr)
			: [val] "r" (val));
		} while (loop);
		break;
	case 8:
		do {
			asm ("//__percpu_xchg_8\n"
			"ldxr %[ret], %[ptr]\n"
			"stxr %w[loop], %[val], %[ptr]\n"
			: [loop] "=&r"(loop), [ret] "=&r"(ret),
			  [ptr] "+Q"(*(u64 *)ptr)
			: [val] "r" (val));
		} while (loop);
		break;
	default:
		BUILD_BUG();
	}

	return ret;
}

#define _percpu_add(pcp, val) \
	__percpu_add(raw_cpu_ptr(&(pcp)), val, sizeof(pcp))

#define _percpu_add_return(pcp, val) (typeof(pcp)) (_percpu_add(pcp, val))

#define _percpu_and(pcp, val) \
	__percpu_and(raw_cpu_ptr(&(pcp)), val, sizeof(pcp))

#define _percpu_or(pcp, val) \
	__percpu_or(raw_cpu_ptr(&(pcp)), val, sizeof(pcp))

#define _percpu_read(pcp) (typeof(pcp))	\
	(__percpu_read(raw_cpu_ptr(&(pcp)), sizeof(pcp)))

#define _percpu_write(pcp, val) \
	__percpu_write(raw_cpu_ptr(&(pcp)), (unsigned long)(val), sizeof(pcp))

#define _percpu_xchg(pcp, val) (typeof(pcp)) \
	(__percpu_xchg(raw_cpu_ptr(&(pcp)), (unsigned long)(val), sizeof(pcp)))

#define this_cpu_add_1(pcp, val) _percpu_add(pcp, val)
#define this_cpu_add_2(pcp, val) _percpu_add(pcp, val)
#define this_cpu_add_4(pcp, val) _percpu_add(pcp, val)
#define this_cpu_add_8(pcp, val) _percpu_add(pcp, val)

#define this_cpu_add_return_1(pcp, val) _percpu_add_return(pcp, val)
#define this_cpu_add_return_2(pcp, val) _percpu_add_return(pcp, val)
#define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val)
#define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val)

#define this_cpu_and_1(pcp, val) _percpu_and(pcp, val)
#define this_cpu_and_2(pcp, val) _percpu_and(pcp, val)
#define this_cpu_and_4(pcp, val) _percpu_and(pcp, val)
#define this_cpu_and_8(pcp, val) _percpu_and(pcp, val)

#define this_cpu_or_1(pcp, val) _percpu_or(pcp, val)
#define this_cpu_or_2(pcp, val) _percpu_or(pcp, val)
#define this_cpu_or_4(pcp, val) _percpu_or(pcp, val)
#define this_cpu_or_8(pcp, val) _percpu_or(pcp, val)

#define this_cpu_read_1(pcp) _percpu_read(pcp)
#define this_cpu_read_2(pcp) _percpu_read(pcp)
#define this_cpu_read_4(pcp) _percpu_read(pcp)
#define this_cpu_read_8(pcp) _percpu_read(pcp)

#define this_cpu_write_1(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_2(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_4(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_8(pcp, val) _percpu_write(pcp, val)

#define this_cpu_xchg_1(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_2(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val)

#include <asm-generic/percpu.h>

#endif /* __ASM_PERCPU_H */