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1965aae3
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1#ifndef _ASM_X86_PERCPU_H
2#define _ASM_X86_PERCPU_H
3334052a 3
1a51e3a0 4#ifdef CONFIG_X86_64
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5#define __percpu_seg gs
6#define __percpu_mov_op movq
1a51e3a0 7#else
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8#define __percpu_seg fs
9#define __percpu_mov_op movl
96a388de 10#endif
3334052a 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
9939ddaf 27#define PER_CPU(var, reg) \
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28 __percpu_mov_op %__percpu_seg:this_cpu_off, reg; \
29 lea var(reg), reg
30#define PER_CPU_VAR(var) %__percpu_seg:var
3334052a 31#else /* ! SMP */
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32#define PER_CPU(var, reg) __percpu_mov_op $var, reg
33#define PER_CPU_VAR(var) var
3334052a 34#endif /* SMP */
35
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36#ifdef CONFIG_X86_64_SMP
37#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
38#else
dd17c8f7 39#define INIT_PER_CPU_VAR(var) var
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40#endif
41
3334052a 42#else /* ...!ASSEMBLY */
43
e59a1bb2 44#include <linux/kernel.h>
9939ddaf 45#include <linux/stringify.h>
3334052a 46
9939ddaf 47#ifdef CONFIG_SMP
87b26406 48#define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x
6dbde353 49#define __my_cpu_offset percpu_read(this_cpu_off)
9939ddaf 50#else
ed8d9adf 51#define __percpu_arg(x) "%P" #x
9939ddaf 52#endif
3334052a 53
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54/*
55 * Initialized pointers to per-cpu variables needed for the boot
56 * processor need to use these macros to get the proper address
57 * offset from __per_cpu_load on SMP.
58 *
59 * There also must be an entry in vmlinux_64.lds.S
60 */
61#define DECLARE_INIT_PER_CPU(var) \
dd17c8f7 62 extern typeof(var) init_per_cpu_var(var)
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63
64#ifdef CONFIG_X86_64_SMP
65#define init_per_cpu_var(var) init_per_cpu__##var
66#else
dd17c8f7 67#define init_per_cpu_var(var) var
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68#endif
69
3334052a 70/* For arch-specific code, we can use direct single-insn ops (they
71 * don't give an lvalue though). */
72extern void __bad_percpu_size(void);
73
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74#define percpu_to_op(op, var, val) \
75do { \
0f5e4816 76 typedef typeof(var) pto_T__; \
bc9e3be2 77 if (0) { \
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78 pto_T__ pto_tmp__; \
79 pto_tmp__ = (val); \
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80 } \
81 switch (sizeof(var)) { \
82 case 1: \
87b26406 83 asm(op "b %1,"__percpu_arg(0) \
bc9e3be2 84 : "+m" (var) \
0f5e4816 85 : "qi" ((pto_T__)(val))); \
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86 break; \
87 case 2: \
87b26406 88 asm(op "w %1,"__percpu_arg(0) \
bc9e3be2 89 : "+m" (var) \
0f5e4816 90 : "ri" ((pto_T__)(val))); \
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91 break; \
92 case 4: \
87b26406 93 asm(op "l %1,"__percpu_arg(0) \
bc9e3be2 94 : "+m" (var) \
0f5e4816 95 : "ri" ((pto_T__)(val))); \
bc9e3be2 96 break; \
9939ddaf 97 case 8: \
87b26406 98 asm(op "q %1,"__percpu_arg(0) \
9939ddaf 99 : "+m" (var) \
0f5e4816 100 : "re" ((pto_T__)(val))); \
9939ddaf 101 break; \
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102 default: __bad_percpu_size(); \
103 } \
104} while (0)
105
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106/*
107 * Generate a percpu add to memory instruction and optimize code
108 * if a one is added or subtracted.
109 */
110#define percpu_add_op(var, val) \
111do { \
112 typedef typeof(var) pao_T__; \
113 const int pao_ID__ = (__builtin_constant_p(val) && \
114 ((val) == 1 || (val) == -1)) ? (val) : 0; \
115 if (0) { \
116 pao_T__ pao_tmp__; \
117 pao_tmp__ = (val); \
118 } \
119 switch (sizeof(var)) { \
120 case 1: \
121 if (pao_ID__ == 1) \
122 asm("incb "__percpu_arg(0) : "+m" (var)); \
123 else if (pao_ID__ == -1) \
124 asm("decb "__percpu_arg(0) : "+m" (var)); \
125 else \
126 asm("addb %1, "__percpu_arg(0) \
127 : "+m" (var) \
128 : "qi" ((pao_T__)(val))); \
129 break; \
130 case 2: \
131 if (pao_ID__ == 1) \
132 asm("incw "__percpu_arg(0) : "+m" (var)); \
133 else if (pao_ID__ == -1) \
134 asm("decw "__percpu_arg(0) : "+m" (var)); \
135 else \
136 asm("addw %1, "__percpu_arg(0) \
137 : "+m" (var) \
138 : "ri" ((pao_T__)(val))); \
139 break; \
140 case 4: \
141 if (pao_ID__ == 1) \
142 asm("incl "__percpu_arg(0) : "+m" (var)); \
143 else if (pao_ID__ == -1) \
144 asm("decl "__percpu_arg(0) : "+m" (var)); \
145 else \
146 asm("addl %1, "__percpu_arg(0) \
147 : "+m" (var) \
148 : "ri" ((pao_T__)(val))); \
149 break; \
150 case 8: \
151 if (pao_ID__ == 1) \
152 asm("incq "__percpu_arg(0) : "+m" (var)); \
153 else if (pao_ID__ == -1) \
154 asm("decq "__percpu_arg(0) : "+m" (var)); \
155 else \
156 asm("addq %1, "__percpu_arg(0) \
157 : "+m" (var) \
158 : "re" ((pao_T__)(val))); \
159 break; \
160 default: __bad_percpu_size(); \
161 } \
162} while (0)
163
ed8d9adf 164#define percpu_from_op(op, var, constraint) \
bc9e3be2 165({ \
0f5e4816 166 typeof(var) pfo_ret__; \
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167 switch (sizeof(var)) { \
168 case 1: \
87b26406 169 asm(op "b "__percpu_arg(1)",%0" \
0f5e4816 170 : "=q" (pfo_ret__) \
ed8d9adf 171 : constraint); \
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172 break; \
173 case 2: \
87b26406 174 asm(op "w "__percpu_arg(1)",%0" \
0f5e4816 175 : "=r" (pfo_ret__) \
ed8d9adf 176 : constraint); \
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177 break; \
178 case 4: \
87b26406 179 asm(op "l "__percpu_arg(1)",%0" \
0f5e4816 180 : "=r" (pfo_ret__) \
ed8d9adf 181 : constraint); \
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182 break; \
183 case 8: \
87b26406 184 asm(op "q "__percpu_arg(1)",%0" \
0f5e4816 185 : "=r" (pfo_ret__) \
ed8d9adf 186 : constraint); \
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187 break; \
188 default: __bad_percpu_size(); \
189 } \
0f5e4816 190 pfo_ret__; \
bc9e3be2 191})
3334052a 192
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193/*
194 * percpu_read() makes gcc load the percpu variable every time it is
195 * accessed while percpu_read_stable() allows the value to be cached.
196 * percpu_read_stable() is more efficient and can be used if its value
197 * is guaranteed to be valid across cpus. The current users include
198 * get_current() and get_thread_info() both of which are actually
199 * per-thread variables implemented as per-cpu variables and thus
200 * stable for the duration of the respective task.
201 */
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202#define percpu_read(var) percpu_from_op("mov", var, "m" (var))
203#define percpu_read_stable(var) percpu_from_op("mov", var, "p" (&(var)))
204#define percpu_write(var, val) percpu_to_op("mov", var, val)
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205#define percpu_add(var, val) percpu_add_op(var, val)
206#define percpu_sub(var, val) percpu_add_op(var, -(val))
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207#define percpu_and(var, val) percpu_to_op("and", var, val)
208#define percpu_or(var, val) percpu_to_op("or", var, val)
209#define percpu_xor(var, val) percpu_to_op("xor", var, val)
9939ddaf 210
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211#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
212#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
213#define __this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
214
215#define __this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
216#define __this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
217#define __this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
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218#define __this_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
219#define __this_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
220#define __this_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
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221#define __this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
222#define __this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
223#define __this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
224#define __this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
225#define __this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
226#define __this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
227#define __this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
228#define __this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
229#define __this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
230
231#define this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
232#define this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
233#define this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
234#define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
235#define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
236#define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
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237#define this_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
238#define this_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
239#define this_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
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240#define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
241#define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
242#define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
243#define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
244#define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
245#define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
246#define this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
247#define this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
248#define this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
249
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250#define irqsafe_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
251#define irqsafe_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
252#define irqsafe_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
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253#define irqsafe_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
254#define irqsafe_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
255#define irqsafe_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
256#define irqsafe_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
257#define irqsafe_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
258#define irqsafe_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
259#define irqsafe_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val)
260#define irqsafe_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val)
261#define irqsafe_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val)
262
263/*
264 * Per cpu atomic 64 bit operations are only available under 64 bit.
265 * 32 bit must fall back to generic operations.
266 */
267#ifdef CONFIG_X86_64
268#define __this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
269#define __this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
5917dae8 270#define __this_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
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271#define __this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
272#define __this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
273#define __this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
274
275#define this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
276#define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
5917dae8 277#define this_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
30ed1a79
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278#define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
279#define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
280#define this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
281
5917dae8 282#define irqsafe_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
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283#define irqsafe_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
284#define irqsafe_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
285#define irqsafe_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val)
286
287#endif
288
49357d19
TH
289/* This is not atomic against other CPUs -- CPU preemption needs to be off */
290#define x86_test_and_clear_bit_percpu(bit, var) \
291({ \
292 int old__; \
87b26406 293 asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \
dd17c8f7 294 : "=r" (old__), "+m" (var) \
87b26406 295 : "dIr" (bit)); \
49357d19
TH
296 old__; \
297})
298
6dbde353
IM
299#include <asm-generic/percpu.h>
300
301/* We can use this directly for local CPU (faster). */
302DECLARE_PER_CPU(unsigned long, this_cpu_off);
303
3334052a 304#endif /* !__ASSEMBLY__ */
23ca4bba
MT
305
306#ifdef CONFIG_SMP
307
308/*
309 * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
310 * variables that are initialized and accessed before there are per_cpu
311 * areas allocated.
312 */
313
314#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
315 DEFINE_PER_CPU(_type, _name) = _initvalue; \
316 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
317 { [0 ... NR_CPUS-1] = _initvalue }; \
c6a92a25 318 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
23ca4bba
MT
319
320#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
321 EXPORT_PER_CPU_SYMBOL(_name)
322
323#define DECLARE_EARLY_PER_CPU(_type, _name) \
324 DECLARE_PER_CPU(_type, _name); \
325 extern __typeof__(_type) *_name##_early_ptr; \
326 extern __typeof__(_type) _name##_early_map[]
327
328#define early_per_cpu_ptr(_name) (_name##_early_ptr)
329#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
330#define early_per_cpu(_name, _cpu) \
f10fcd47
TH
331 *(early_per_cpu_ptr(_name) ? \
332 &early_per_cpu_ptr(_name)[_cpu] : \
333 &per_cpu(_name, _cpu))
23ca4bba
MT
334
335#else /* !CONFIG_SMP */
336#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
337 DEFINE_PER_CPU(_type, _name) = _initvalue
338
339#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
340 EXPORT_PER_CPU_SYMBOL(_name)
341
342#define DECLARE_EARLY_PER_CPU(_type, _name) \
343 DECLARE_PER_CPU(_type, _name)
344
345#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
346#define early_per_cpu_ptr(_name) NULL
347/* no early_per_cpu_map() */
348
349#endif /* !CONFIG_SMP */
350
1965aae3 351#endif /* _ASM_X86_PERCPU_H */