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Tejun Heo62fde542014-06-17 19:12:34 -04001/*
2 * linux/percpu-defs.h - basic definitions for percpu areas
3 *
4 * DO NOT INCLUDE DIRECTLY OUTSIDE PERCPU IMPLEMENTATION PROPER.
5 *
6 * This file is separate from linux/percpu.h to avoid cyclic inclusion
7 * dependency from arch header files. Only to be included from
8 * asm/percpu.h.
9 *
10 * This file includes macros necessary to declare percpu sections and
11 * variables, and definitions of percpu accessors and operations. It
12 * should provide enough percpu features to arch header files even when
13 * they can only include asm/percpu.h to avoid cyclic inclusion dependency.
14 */
15
David Howells5028eaa2009-04-21 23:00:29 +010016#ifndef _LINUX_PERCPU_DEFS_H
17#define _LINUX_PERCPU_DEFS_H
18
Tejun Heo62fde542014-06-17 19:12:34 -040019#ifdef CONFIG_SMP
20
21#ifdef MODULE
22#define PER_CPU_SHARED_ALIGNED_SECTION ""
23#define PER_CPU_ALIGNED_SECTION ""
24#else
25#define PER_CPU_SHARED_ALIGNED_SECTION "..shared_aligned"
26#define PER_CPU_ALIGNED_SECTION "..shared_aligned"
27#endif
28#define PER_CPU_FIRST_SECTION "..first"
29
30#else
31
32#define PER_CPU_SHARED_ALIGNED_SECTION ""
33#define PER_CPU_ALIGNED_SECTION "..shared_aligned"
34#define PER_CPU_FIRST_SECTION ""
35
36#endif
37
David Howells5028eaa2009-04-21 23:00:29 +010038/*
David Howells5028eaa2009-04-21 23:00:29 +010039 * Base implementations of per-CPU variable declarations and definitions, where
40 * the section in which the variable is to be placed is provided by the
Tejun Heo7c756e62009-06-24 15:13:50 +090041 * 'sec' argument. This may be used to affect the parameters governing the
David Howells5028eaa2009-04-21 23:00:29 +010042 * variable's storage.
43 *
44 * NOTE! The sections for the DECLARE and for the DEFINE must match, lest
45 * linkage errors occur due the compiler generating the wrong code to access
46 * that section.
47 */
Tejun Heo7c756e62009-06-24 15:13:50 +090048#define __PCPU_ATTRS(sec) \
Rusty Russelle0fdb0e2009-10-29 22:34:15 +090049 __percpu __attribute__((section(PER_CPU_BASE_SECTION sec))) \
Tejun Heo7c756e62009-06-24 15:13:50 +090050 PER_CPU_ATTRIBUTES
David Howells5028eaa2009-04-21 23:00:29 +010051
Tejun Heo7c756e62009-06-24 15:13:50 +090052#define __PCPU_DUMMY_ATTRS \
53 __attribute__((section(".discard"), unused))
54
55/*
56 * s390 and alpha modules require percpu variables to be defined as
57 * weak to force the compiler to generate GOT based external
58 * references for them. This is necessary because percpu sections
59 * will be located outside of the usually addressable area.
60 *
61 * This definition puts the following two extra restrictions when
62 * defining percpu variables.
63 *
64 * 1. The symbol must be globally unique, even the static ones.
65 * 2. Static percpu variables cannot be defined inside a function.
66 *
67 * Archs which need weak percpu definitions should define
68 * ARCH_NEEDS_WEAK_PER_CPU in asm/percpu.h when necessary.
69 *
70 * To ensure that the generic code observes the above two
71 * restrictions, if CONFIG_DEBUG_FORCE_WEAK_PER_CPU is set weak
72 * definition is used for all cases.
73 */
74#if defined(ARCH_NEEDS_WEAK_PER_CPU) || defined(CONFIG_DEBUG_FORCE_WEAK_PER_CPU)
75/*
76 * __pcpu_scope_* dummy variable is used to enforce scope. It
77 * receives the static modifier when it's used in front of
78 * DEFINE_PER_CPU() and will trigger build failure if
79 * DECLARE_PER_CPU() is used for the same variable.
80 *
81 * __pcpu_unique_* dummy variable is used to enforce symbol uniqueness
82 * such that hidden weak symbol collision, which will cause unrelated
83 * variables to share the same address, can be detected during build.
84 */
85#define DECLARE_PER_CPU_SECTION(type, name, sec) \
86 extern __PCPU_DUMMY_ATTRS char __pcpu_scope_##name; \
Rusty Russelldd17c8f2009-10-29 22:34:15 +090087 extern __PCPU_ATTRS(sec) __typeof__(type) name
Tejun Heo7c756e62009-06-24 15:13:50 +090088
89#define DEFINE_PER_CPU_SECTION(type, name, sec) \
90 __PCPU_DUMMY_ATTRS char __pcpu_scope_##name; \
Tejun Heo0f5e4812009-10-29 22:34:12 +090091 extern __PCPU_DUMMY_ATTRS char __pcpu_unique_##name; \
Tejun Heo7c756e62009-06-24 15:13:50 +090092 __PCPU_DUMMY_ATTRS char __pcpu_unique_##name; \
Tejun Heob1a0fbf2013-12-04 10:12:40 -050093 extern __PCPU_ATTRS(sec) __typeof__(type) name; \
Tejun Heoc43768c2009-07-04 07:13:18 +090094 __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES __weak \
Rusty Russelldd17c8f2009-10-29 22:34:15 +090095 __typeof__(type) name
Tejun Heo7c756e62009-06-24 15:13:50 +090096#else
97/*
98 * Normal declaration and definition macros.
99 */
100#define DECLARE_PER_CPU_SECTION(type, name, sec) \
Rusty Russelldd17c8f2009-10-29 22:34:15 +0900101 extern __PCPU_ATTRS(sec) __typeof__(type) name
Tejun Heo7c756e62009-06-24 15:13:50 +0900102
103#define DEFINE_PER_CPU_SECTION(type, name, sec) \
Tejun Heoc43768c2009-07-04 07:13:18 +0900104 __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES \
Rusty Russelldd17c8f2009-10-29 22:34:15 +0900105 __typeof__(type) name
Tejun Heo7c756e62009-06-24 15:13:50 +0900106#endif
David Howells5028eaa2009-04-21 23:00:29 +0100107
108/*
109 * Variant on the per-CPU variable declaration/definition theme used for
110 * ordinary per-CPU variables.
111 */
112#define DECLARE_PER_CPU(type, name) \
113 DECLARE_PER_CPU_SECTION(type, name, "")
114
115#define DEFINE_PER_CPU(type, name) \
116 DEFINE_PER_CPU_SECTION(type, name, "")
117
118/*
119 * Declaration/definition used for per-CPU variables that must come first in
120 * the set of variables.
121 */
122#define DECLARE_PER_CPU_FIRST(type, name) \
123 DECLARE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
124
125#define DEFINE_PER_CPU_FIRST(type, name) \
126 DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
127
128/*
129 * Declaration/definition used for per-CPU variables that must be cacheline
130 * aligned under SMP conditions so that, whilst a particular instance of the
131 * data corresponds to a particular CPU, inefficiencies due to direct access by
132 * other CPUs are reduced by preventing the data from unnecessarily spanning
133 * cachelines.
134 *
135 * An example of this would be statistical data, where each CPU's set of data
136 * is updated by that CPU alone, but the data from across all CPUs is collated
137 * by a CPU processing a read from a proc file.
138 */
139#define DECLARE_PER_CPU_SHARED_ALIGNED(type, name) \
140 DECLARE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
141 ____cacheline_aligned_in_smp
142
143#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
144 DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
145 ____cacheline_aligned_in_smp
146
Jeremy Fitzhardinge53f82452009-09-03 14:31:44 -0700147#define DECLARE_PER_CPU_ALIGNED(type, name) \
148 DECLARE_PER_CPU_SECTION(type, name, PER_CPU_ALIGNED_SECTION) \
149 ____cacheline_aligned
150
151#define DEFINE_PER_CPU_ALIGNED(type, name) \
152 DEFINE_PER_CPU_SECTION(type, name, PER_CPU_ALIGNED_SECTION) \
153 ____cacheline_aligned
154
David Howells5028eaa2009-04-21 23:00:29 +0100155/*
156 * Declaration/definition used for per-CPU variables that must be page aligned.
157 */
Tejun Heo3e352aa2009-08-03 14:10:11 +0900158#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name) \
Denys Vlasenko3d9a8542010-02-20 01:03:43 +0100159 DECLARE_PER_CPU_SECTION(type, name, "..page_aligned") \
Tejun Heo3e352aa2009-08-03 14:10:11 +0900160 __aligned(PAGE_SIZE)
David Howells5028eaa2009-04-21 23:00:29 +0100161
162#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
Denys Vlasenko3d9a8542010-02-20 01:03:43 +0100163 DEFINE_PER_CPU_SECTION(type, name, "..page_aligned") \
Tejun Heo3e352aa2009-08-03 14:10:11 +0900164 __aligned(PAGE_SIZE)
David Howells5028eaa2009-04-21 23:00:29 +0100165
166/*
Shaohua Lic957ef22010-10-20 11:07:02 +0800167 * Declaration/definition used for per-CPU variables that must be read mostly.
168 */
169#define DECLARE_PER_CPU_READ_MOSTLY(type, name) \
170 DECLARE_PER_CPU_SECTION(type, name, "..readmostly")
171
172#define DEFINE_PER_CPU_READ_MOSTLY(type, name) \
173 DEFINE_PER_CPU_SECTION(type, name, "..readmostly")
174
175/*
Tejun Heo545695f2009-10-29 22:34:15 +0900176 * Intermodule exports for per-CPU variables. sparse forgets about
177 * address space across EXPORT_SYMBOL(), change EXPORT_SYMBOL() to
178 * noop if __CHECKER__.
David Howells5028eaa2009-04-21 23:00:29 +0100179 */
Tejun Heo545695f2009-10-29 22:34:15 +0900180#ifndef __CHECKER__
Rusty Russelldd17c8f2009-10-29 22:34:15 +0900181#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(var)
182#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(var)
Tejun Heo545695f2009-10-29 22:34:15 +0900183#else
184#define EXPORT_PER_CPU_SYMBOL(var)
185#define EXPORT_PER_CPU_SYMBOL_GPL(var)
186#endif
David Howells5028eaa2009-04-21 23:00:29 +0100187
Tejun Heo62fde542014-06-17 19:12:34 -0400188/*
189 * Accessors and operations.
190 */
191#ifndef __ASSEMBLY__
192
Tejun Heo9c28278a22014-06-17 19:12:39 -0400193/*
194 * Macro which verifies @ptr is a percpu pointer without evaluating
195 * @ptr. This is to be used in percpu accessors to verify that the
196 * input parameter is a percpu pointer.
197 *
198 * + 0 is required in order to convert the pointer type from a
199 * potential array type to a pointer to a single item of the array.
200 */
201#define __verify_pcpu_ptr(ptr) do { \
202 const void __percpu *__vpp_verify = (typeof((ptr) + 0))NULL; \
203 (void)__vpp_verify; \
204} while (0)
205
Tejun Heo62fde542014-06-17 19:12:34 -0400206#ifdef CONFIG_SMP
207
208/*
209 * Add an offset to a pointer but keep the pointer as-is. Use RELOC_HIDE()
210 * to prevent the compiler from making incorrect assumptions about the
211 * pointer value. The weird cast keeps both GCC and sparse happy.
212 */
213#define SHIFT_PERCPU_PTR(__p, __offset) ({ \
214 __verify_pcpu_ptr((__p)); \
215 RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)); \
216})
217
Tejun Heo3b8ed912014-06-17 19:12:37 -0400218#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
219#define raw_cpu_ptr(ptr) arch_raw_cpu_ptr(ptr)
Tejun Heo62fde542014-06-17 19:12:34 -0400220
221#ifdef CONFIG_DEBUG_PREEMPT
222#define this_cpu_ptr(ptr) SHIFT_PERCPU_PTR(ptr, my_cpu_offset)
223#else
224#define this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
225#endif
226
Tejun Heo62fde542014-06-17 19:12:34 -0400227#else /* CONFIG_SMP */
228
229#define VERIFY_PERCPU_PTR(__p) ({ \
230 __verify_pcpu_ptr((__p)); \
231 (typeof(*(__p)) __kernel __force *)(__p); \
232})
233
Tejun Heo3b8ed912014-06-17 19:12:37 -0400234#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
235#define raw_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
236#define this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
Tejun Heo62fde542014-06-17 19:12:34 -0400237
238#endif /* CONFIG_SMP */
239
Tejun Heo3b8ed912014-06-17 19:12:37 -0400240#define per_cpu(var, cpu) (*per_cpu_ptr(&(var), cpu))
241#define __raw_get_cpu_var(var) (*raw_cpu_ptr(&(var)))
242#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
243
Tejun Heo62fde542014-06-17 19:12:34 -0400244/* keep until we have removed all uses of __this_cpu_ptr */
245#define __this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
246
Tejun Heo9defda12014-06-17 19:12:34 -0400247/*
248 * Must be an lvalue. Since @var must be a simple identifier,
249 * we force a syntax error here if it isn't.
250 */
251#define get_cpu_var(var) (*({ \
252 preempt_disable(); \
253 this_cpu_ptr(&var); }))
254
255/*
256 * The weird & is necessary because sparse considers (void)(var) to be
257 * a direct dereference of percpu variable (var).
258 */
259#define put_cpu_var(var) do { \
260 (void)&(var); \
261 preempt_enable(); \
262} while (0)
263
264#define get_cpu_ptr(var) ({ \
265 preempt_disable(); \
266 this_cpu_ptr(var); })
267
268#define put_cpu_ptr(var) do { \
269 (void)(var); \
270 preempt_enable(); \
271} while (0)
272
Tejun Heoa32f8d82014-06-17 19:12:39 -0400273/*
274 * Branching function to split up a function into a set of functions that
275 * are called for different scalar sizes of the objects handled.
276 */
277
278extern void __bad_size_call_parameter(void);
279
280#ifdef CONFIG_DEBUG_PREEMPT
281extern void __this_cpu_preempt_check(const char *op);
282#else
283static inline void __this_cpu_preempt_check(const char *op) { }
284#endif
285
286#define __pcpu_size_call_return(stem, variable) \
287({ typeof(variable) pscr_ret__; \
288 __verify_pcpu_ptr(&(variable)); \
289 switch(sizeof(variable)) { \
290 case 1: pscr_ret__ = stem##1(variable);break; \
291 case 2: pscr_ret__ = stem##2(variable);break; \
292 case 4: pscr_ret__ = stem##4(variable);break; \
293 case 8: pscr_ret__ = stem##8(variable);break; \
294 default: \
295 __bad_size_call_parameter();break; \
296 } \
297 pscr_ret__; \
298})
299
300#define __pcpu_size_call_return2(stem, variable, ...) \
301({ \
302 typeof(variable) pscr2_ret__; \
303 __verify_pcpu_ptr(&(variable)); \
304 switch(sizeof(variable)) { \
305 case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \
306 case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \
307 case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \
308 case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \
309 default: \
310 __bad_size_call_parameter(); break; \
311 } \
312 pscr2_ret__; \
313})
314
315/*
316 * Special handling for cmpxchg_double. cmpxchg_double is passed two
317 * percpu variables. The first has to be aligned to a double word
318 * boundary and the second has to follow directly thereafter.
319 * We enforce this on all architectures even if they don't support
320 * a double cmpxchg instruction, since it's a cheap requirement, and it
321 * avoids breaking the requirement for architectures with the instruction.
322 */
323#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \
324({ \
325 bool pdcrb_ret__; \
326 __verify_pcpu_ptr(&pcp1); \
327 BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \
328 VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \
329 VM_BUG_ON((unsigned long)(&pcp2) != \
330 (unsigned long)(&pcp1) + sizeof(pcp1)); \
331 switch(sizeof(pcp1)) { \
332 case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \
333 case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \
334 case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \
335 case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \
336 default: \
337 __bad_size_call_parameter(); break; \
338 } \
339 pdcrb_ret__; \
340})
341
342#define __pcpu_size_call(stem, variable, ...) \
343do { \
344 __verify_pcpu_ptr(&(variable)); \
345 switch(sizeof(variable)) { \
346 case 1: stem##1(variable, __VA_ARGS__);break; \
347 case 2: stem##2(variable, __VA_ARGS__);break; \
348 case 4: stem##4(variable, __VA_ARGS__);break; \
349 case 8: stem##8(variable, __VA_ARGS__);break; \
350 default: \
351 __bad_size_call_parameter();break; \
352 } \
353} while (0)
354
355/*
356 * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com>
357 *
358 * Optimized manipulation for memory allocated through the per cpu
359 * allocator or for addresses of per cpu variables.
360 *
361 * These operation guarantee exclusivity of access for other operations
362 * on the *same* processor. The assumption is that per cpu data is only
363 * accessed by a single processor instance (the current one).
364 *
365 * The arch code can provide optimized implementation by defining macros
366 * for certain scalar sizes. F.e. provide this_cpu_add_2() to provide per
367 * cpu atomic operations for 2 byte sized RMW actions. If arch code does
368 * not provide operations for a scalar size then the fallback in the
369 * generic code will be used.
370 */
371
372/*
373 * Generic percpu operations for contexts where we do not want to do
374 * any checks for preemptiosn.
375 *
376 * If there is no other protection through preempt disable and/or
377 * disabling interupts then one of these RMW operations can show unexpected
378 * behavior because the execution thread was rescheduled on another processor
379 * or an interrupt occurred and the same percpu variable was modified from
380 * the interrupt context.
381 */
382# define raw_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp))
383# define raw_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val))
384# define raw_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val))
385# define raw_cpu_sub(pcp, val) raw_cpu_add((pcp), -(val))
386# define raw_cpu_inc(pcp) raw_cpu_add((pcp), 1)
387# define raw_cpu_dec(pcp) raw_cpu_sub((pcp), 1)
388# define raw_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val))
389# define raw_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val))
390# define raw_cpu_add_return(pcp, val) \
391 __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)
392#define raw_cpu_sub_return(pcp, val) raw_cpu_add_return(pcp, -(typeof(pcp))(val))
393#define raw_cpu_inc_return(pcp) raw_cpu_add_return(pcp, 1)
394#define raw_cpu_dec_return(pcp) raw_cpu_add_return(pcp, -1)
395# define raw_cpu_xchg(pcp, nval) \
396 __pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)
397# define raw_cpu_cmpxchg(pcp, oval, nval) \
398 __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)
399# define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
400 __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
401
402/*
403 * Generic percpu operations for context that are safe from preemption/interrupts.
404 */
405# define __this_cpu_read(pcp) \
406 (__this_cpu_preempt_check("read"),__pcpu_size_call_return(raw_cpu_read_, (pcp)))
407
408# define __this_cpu_write(pcp, val) \
409do { __this_cpu_preempt_check("write"); \
410 __pcpu_size_call(raw_cpu_write_, (pcp), (val)); \
411} while (0)
412
413# define __this_cpu_add(pcp, val) \
414do { __this_cpu_preempt_check("add"); \
415 __pcpu_size_call(raw_cpu_add_, (pcp), (val)); \
416} while (0)
417
418# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(typeof(pcp))(val))
419# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
420# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
421
422# define __this_cpu_and(pcp, val) \
423do { __this_cpu_preempt_check("and"); \
424 __pcpu_size_call(raw_cpu_and_, (pcp), (val)); \
425} while (0)
426
427# define __this_cpu_or(pcp, val) \
428do { __this_cpu_preempt_check("or"); \
429 __pcpu_size_call(raw_cpu_or_, (pcp), (val)); \
430} while (0)
431
432# define __this_cpu_add_return(pcp, val) \
433 (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val))
434
435#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val))
436#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1)
437#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1)
438
439# define __this_cpu_xchg(pcp, nval) \
440 (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval))
441
442# define __this_cpu_cmpxchg(pcp, oval, nval) \
443 (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval))
444
445# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
446 (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)))
447
448/*
449 * this_cpu_*() operations are used for accesses that must be done in a
450 * preemption safe way since we know that the context is not preempt
451 * safe. Interrupts may occur. If the interrupt modifies the variable too
452 * then RMW actions will not be reliable.
453 */
454# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
455# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
456# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
457# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(typeof(pcp))(val))
458# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
459# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
460# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
461# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
462# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
463#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(typeof(pcp))(val))
464#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
465#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
466# define this_cpu_xchg(pcp, nval) \
467 __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
468# define this_cpu_cmpxchg(pcp, oval, nval) \
469 __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
470
471/*
472 * cmpxchg_double replaces two adjacent scalars at once. The first
473 * two parameters are per cpu variables which have to be of the same
474 * size. A truth value is returned to indicate success or failure
475 * (since a double register result is difficult to handle). There is
476 * very limited hardware support for these operations, so only certain
477 * sizes may work.
478 */
479# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
480 __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
481
Tejun Heo62fde542014-06-17 19:12:34 -0400482#endif /* __ASSEMBLY__ */
David Howells5028eaa2009-04-21 23:00:29 +0100483#endif /* _LINUX_PERCPU_DEFS_H */