Line data Source code
1 : #ifndef _ASM_X86_PERCPU_H
2 : #define _ASM_X86_PERCPU_H
3 :
4 : #ifdef CONFIG_X86_64
5 : #define __percpu_seg gs
6 : #define __percpu_mov_op movq
7 : #else
8 : #define __percpu_seg fs
9 : #define __percpu_mov_op movl
10 : #endif
11 :
12 : #ifdef __ASSEMBLY__
13 :
14 : /*
15 : * PER_CPU finds an address of a per-cpu variable.
16 : *
17 : * Args:
18 : * var - variable name
19 : * reg - 32bit register
20 : *
21 : * The resulting address is stored in the "reg" argument.
22 : *
23 : * Example:
24 : * PER_CPU(cpu_gdt_descr, %ebx)
25 : */
26 : #ifdef CONFIG_SMP
27 : #define PER_CPU(var, reg) \
28 : __percpu_mov_op %__percpu_seg:per_cpu__this_cpu_off, reg; \
29 : lea per_cpu__##var(reg), reg
30 : #define PER_CPU_VAR(var) %__percpu_seg:per_cpu__##var
31 : #else /* ! SMP */
32 : #define PER_CPU(var, reg) \
33 : __percpu_mov_op $per_cpu__##var, reg
34 : #define PER_CPU_VAR(var) per_cpu__##var
35 : #endif /* SMP */
36 :
37 : #ifdef CONFIG_X86_64_SMP
38 : #define INIT_PER_CPU_VAR(var) init_per_cpu__##var
39 : #else
40 : #define INIT_PER_CPU_VAR(var) per_cpu__##var
41 : #endif
42 :
43 : #else /* ...!ASSEMBLY */
44 :
45 : #include <linux/kernel.h>
46 : #include <linux/stringify.h>
47 :
48 : #ifdef CONFIG_SMP
49 : #define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x
50 : #define __my_cpu_offset percpu_read(this_cpu_off)
51 : #else
52 : #define __percpu_arg(x) "%P" #x
53 : #endif
54 :
55 : /*
56 : * Initialized pointers to per-cpu variables needed for the boot
57 : * processor need to use these macros to get the proper address
58 : * offset from __per_cpu_load on SMP.
59 : *
60 : * There also must be an entry in vmlinux_64.lds.S
61 : */
62 : #define DECLARE_INIT_PER_CPU(var) \
63 : extern typeof(per_cpu_var(var)) init_per_cpu_var(var)
64 :
65 : #ifdef CONFIG_X86_64_SMP
66 : #define init_per_cpu_var(var) init_per_cpu__##var
67 : #else
68 : #define init_per_cpu_var(var) per_cpu_var(var)
69 : #endif
70 :
71 : /* For arch-specific code, we can use direct single-insn ops (they
72 : * don't give an lvalue though). */
73 : extern void __bad_percpu_size(void);
74 :
75 : #define percpu_to_op(op, var, val) \
76 : do { \
77 : typedef typeof(var) pto_T__; \
78 : if (0) { \
79 : pto_T__ pto_tmp__; \
80 : pto_tmp__ = (val); \
81 : } \
82 : switch (sizeof(var)) { \
83 : case 1: \
84 : asm(op "b %1,"__percpu_arg(0) \
85 : : "+m" (var) \
86 : : "qi" ((pto_T__)(val))); \
87 : break; \
88 : case 2: \
89 : asm(op "w %1,"__percpu_arg(0) \
90 : : "+m" (var) \
91 : : "ri" ((pto_T__)(val))); \
92 : break; \
93 : case 4: \
94 : asm(op "l %1,"__percpu_arg(0) \
95 : : "+m" (var) \
96 : : "ri" ((pto_T__)(val))); \
97 : break; \
98 : case 8: \
99 : asm(op "q %1,"__percpu_arg(0) \
100 : : "+m" (var) \
101 : : "re" ((pto_T__)(val))); \
102 : break; \
103 : default: __bad_percpu_size(); \
104 : } \
105 : } while (0)
106 :
107 : #define percpu_from_op(op, var, constraint) \
108 : ({ \
109 : typeof(var) pfo_ret__; \
110 : switch (sizeof(var)) { \
111 : case 1: \
112 : asm(op "b "__percpu_arg(1)",%0" \
113 : : "=q" (pfo_ret__) \
114 : : constraint); \
115 : break; \
116 : case 2: \
117 : asm(op "w "__percpu_arg(1)",%0" \
118 : : "=r" (pfo_ret__) \
119 : : constraint); \
120 : break; \
121 : case 4: \
122 : asm(op "l "__percpu_arg(1)",%0" \
123 : : "=r" (pfo_ret__) \
124 : : constraint); \
125 : break; \
126 : case 8: \
127 : asm(op "q "__percpu_arg(1)",%0" \
128 : : "=r" (pfo_ret__) \
129 : : constraint); \
130 : break; \
131 : default: __bad_percpu_size(); \
132 : } \
133 : pfo_ret__; \
134 : })
135 :
136 : /*
137 : * percpu_read() makes gcc load the percpu variable every time it is
138 : * accessed while percpu_read_stable() allows the value to be cached.
139 : * percpu_read_stable() is more efficient and can be used if its value
140 : * is guaranteed to be valid across cpus. The current users include
141 : * get_current() and get_thread_info() both of which are actually
142 : * per-thread variables implemented as per-cpu variables and thus
143 : * stable for the duration of the respective task.
144 : */
145 : #define percpu_read(var) percpu_from_op("mov", per_cpu__##var, \
146 : "m" (per_cpu__##var))
147 : #define percpu_read_stable(var) percpu_from_op("mov", per_cpu__##var, \
148 : "p" (&per_cpu__##var))
149 : #define percpu_write(var, val) percpu_to_op("mov", per_cpu__##var, val)
150 : #define percpu_add(var, val) percpu_to_op("add", per_cpu__##var, val)
151 : #define percpu_sub(var, val) percpu_to_op("sub", per_cpu__##var, val)
152 : #define percpu_and(var, val) percpu_to_op("and", per_cpu__##var, val)
153 : #define percpu_or(var, val) percpu_to_op("or", per_cpu__##var, val)
154 : #define percpu_xor(var, val) percpu_to_op("xor", per_cpu__##var, val)
155 :
156 : #define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
157 : #define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
158 : #define __this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
159 :
160 : #define __this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
161 : #define __this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
162 : #define __this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
163 : #define __this_cpu_add_1(pcp, val) percpu_to_op("add", (pcp), val)
164 : #define __this_cpu_add_2(pcp, val) percpu_to_op("add", (pcp), val)
165 : #define __this_cpu_add_4(pcp, val) percpu_to_op("add", (pcp), val)
166 : #define __this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
167 : #define __this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
168 : #define __this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
169 : #define __this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
170 : #define __this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
171 : #define __this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
172 : #define __this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
173 : #define __this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
174 : #define __this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
175 :
176 : #define this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
177 : #define this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
178 : #define this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
179 : #define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
180 : #define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
181 : #define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
182 : #define this_cpu_add_1(pcp, val) percpu_to_op("add", (pcp), val)
183 : #define this_cpu_add_2(pcp, val) percpu_to_op("add", (pcp), val)
184 : #define this_cpu_add_4(pcp, val) percpu_to_op("add", (pcp), val)
185 : #define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
186 : #define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
187 : #define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
188 : #define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
189 : #define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
190 : #define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
191 : #define this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
192 : #define this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
193 : #define this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
194 :
195 : #define irqsafe_cpu_add_1(pcp, val) percpu_to_op("add", (pcp), val)
196 : #define irqsafe_cpu_add_2(pcp, val) percpu_to_op("add", (pcp), val)
197 : #define irqsafe_cpu_add_4(pcp, val) percpu_to_op("add", (pcp), val)
198 : #define irqsafe_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
199 : #define irqsafe_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
200 : #define irqsafe_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
201 : #define irqsafe_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
202 : #define irqsafe_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
203 : #define irqsafe_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
204 : #define irqsafe_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
205 : #define irqsafe_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
206 : #define irqsafe_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
207 :
208 : /*
209 : * Per cpu atomic 64 bit operations are only available under 64 bit.
210 : * 32 bit must fall back to generic operations.
211 : */
212 : #ifdef CONFIG_X86_64
213 : #define __this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
214 : #define __this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
215 : #define __this_cpu_add_8(pcp, val) percpu_to_op("add", (pcp), val)
216 : #define __this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
217 : #define __this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
218 : #define __this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
219 :
220 : #define this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
221 : #define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
222 : #define this_cpu_add_8(pcp, val) percpu_to_op("add", (pcp), val)
223 : #define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
224 : #define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
225 : #define this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
226 :
227 : #define irqsafe_cpu_add_8(pcp, val) percpu_to_op("add", (pcp), val)
228 : #define irqsafe_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
229 : #define irqsafe_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
230 : #define irqsafe_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
231 :
232 : #endif
233 :
234 : /* This is not atomic against other CPUs -- CPU preemption needs to be off */
235 : #define x86_test_and_clear_bit_percpu(bit, var) \
236 : ({ \
237 : int old__; \
238 : asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \
239 : : "=r" (old__), "+m" (per_cpu__##var) \
240 : : "dIr" (bit)); \
241 : old__; \
242 : })
243 :
244 : #include <asm-generic/percpu.h>
245 :
246 : /* We can use this directly for local CPU (faster). */
247 1 : DECLARE_PER_CPU(unsigned long, this_cpu_off);
248 :
249 : #endif /* !__ASSEMBLY__ */
250 :
251 : #ifdef CONFIG_SMP
252 :
253 : /*
254 : * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
255 : * variables that are initialized and accessed before there are per_cpu
256 : * areas allocated.
257 : */
258 :
259 : #define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
260 : DEFINE_PER_CPU(_type, _name) = _initvalue; \
261 : __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
262 : { [0 ... NR_CPUS-1] = _initvalue }; \
263 : __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
264 :
265 : #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
266 : EXPORT_PER_CPU_SYMBOL(_name)
267 :
268 : #define DECLARE_EARLY_PER_CPU(_type, _name) \
269 : DECLARE_PER_CPU(_type, _name); \
270 : extern __typeof__(_type) *_name##_early_ptr; \
271 : extern __typeof__(_type) _name##_early_map[]
272 :
273 : #define early_per_cpu_ptr(_name) (_name##_early_ptr)
274 : #define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
275 : #define early_per_cpu(_name, _cpu) \
276 : *(early_per_cpu_ptr(_name) ? \
277 : &early_per_cpu_ptr(_name)[_cpu] : \
278 : &per_cpu(_name, _cpu))
279 :
280 : #else /* !CONFIG_SMP */
281 : #define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
282 : DEFINE_PER_CPU(_type, _name) = _initvalue
283 :
284 : #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
285 : EXPORT_PER_CPU_SYMBOL(_name)
286 :
287 : #define DECLARE_EARLY_PER_CPU(_type, _name) \
288 : DECLARE_PER_CPU(_type, _name)
289 :
290 : #define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
291 : #define early_per_cpu_ptr(_name) NULL
292 : /* no early_per_cpu_map() */
293 :
294 : #endif /* !CONFIG_SMP */
295 :
296 : #endif /* _ASM_X86_PERCPU_H */
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