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authorTejun Heo <tj@kernel.org>2014-06-18 03:12:39 +0400
committerTejun Heo <tj@kernel.org>2014-06-18 03:12:39 +0400
commita32f8d8eda8bd49017ac5f88e2b859f1f582557f (patch)
tree8ef931b5060b802d41c8cafe8356b5d155a5f8d8 /include/linux/percpu.h
parent47b69ad673d9aa53c1d6032a6a522fc0ce8d6fc1 (diff)
downloadlinux-a32f8d8eda8bd49017ac5f88e2b859f1f582557f.tar.xz
percpu: move {raw|this}_cpu_*() definitions to include/linux/percpu-defs.h
We're in the process of moving all percpu accessors and operations to include/linux/percpu-defs.h so that they're available to arch headers without having to include full include/linux/percpu.h which may cause cyclic inclusion dependency. This patch moves {raw|this}_cpu_*() definitions from include/linux/percpu.h to include/linux/percpu-defs.h. The code is moved mostly verbatim; however, raw_cpu_*() are placed above this_cpu_*() which is more conventional as the raw operations may be used to defined other variants. This is pure reorganization. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Christoph Lameter <cl@linux.com>
Diffstat (limited to 'include/linux/percpu.h')
-rw-r--r--include/linux/percpu.h208
1 files changed, 0 insertions, 208 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 20b953532596..6f61b61b7996 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -129,212 +129,4 @@ extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
#define alloc_percpu(type) \
(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
-/*
- * Branching function to split up a function into a set of functions that
- * are called for different scalar sizes of the objects handled.
- */
-
-extern void __bad_size_call_parameter(void);
-
-#ifdef CONFIG_DEBUG_PREEMPT
-extern void __this_cpu_preempt_check(const char *op);
-#else
-static inline void __this_cpu_preempt_check(const char *op) { }
-#endif
-
-#define __pcpu_size_call_return(stem, variable) \
-({ typeof(variable) pscr_ret__; \
- __verify_pcpu_ptr(&(variable)); \
- switch(sizeof(variable)) { \
- case 1: pscr_ret__ = stem##1(variable);break; \
- case 2: pscr_ret__ = stem##2(variable);break; \
- case 4: pscr_ret__ = stem##4(variable);break; \
- case 8: pscr_ret__ = stem##8(variable);break; \
- default: \
- __bad_size_call_parameter();break; \
- } \
- pscr_ret__; \
-})
-
-#define __pcpu_size_call_return2(stem, variable, ...) \
-({ \
- typeof(variable) pscr2_ret__; \
- __verify_pcpu_ptr(&(variable)); \
- switch(sizeof(variable)) { \
- case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \
- case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \
- case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \
- case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \
- default: \
- __bad_size_call_parameter(); break; \
- } \
- pscr2_ret__; \
-})
-
-/*
- * Special handling for cmpxchg_double. cmpxchg_double is passed two
- * percpu variables. The first has to be aligned to a double word
- * boundary and the second has to follow directly thereafter.
- * We enforce this on all architectures even if they don't support
- * a double cmpxchg instruction, since it's a cheap requirement, and it
- * avoids breaking the requirement for architectures with the instruction.
- */
-#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \
-({ \
- bool pdcrb_ret__; \
- __verify_pcpu_ptr(&pcp1); \
- BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \
- VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \
- VM_BUG_ON((unsigned long)(&pcp2) != \
- (unsigned long)(&pcp1) + sizeof(pcp1)); \
- switch(sizeof(pcp1)) { \
- case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \
- case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \
- case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \
- case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \
- default: \
- __bad_size_call_parameter(); break; \
- } \
- pdcrb_ret__; \
-})
-
-#define __pcpu_size_call(stem, variable, ...) \
-do { \
- __verify_pcpu_ptr(&(variable)); \
- switch(sizeof(variable)) { \
- case 1: stem##1(variable, __VA_ARGS__);break; \
- case 2: stem##2(variable, __VA_ARGS__);break; \
- case 4: stem##4(variable, __VA_ARGS__);break; \
- case 8: stem##8(variable, __VA_ARGS__);break; \
- default: \
- __bad_size_call_parameter();break; \
- } \
-} while (0)
-
-/*
- * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com>
- *
- * Optimized manipulation for memory allocated through the per cpu
- * allocator or for addresses of per cpu variables.
- *
- * These operation guarantee exclusivity of access for other operations
- * on the *same* processor. The assumption is that per cpu data is only
- * accessed by a single processor instance (the current one).
- *
- * The first group is used for accesses that must be done in a
- * preemption safe way since we know that the context is not preempt
- * safe. Interrupts may occur. If the interrupt modifies the variable
- * too then RMW actions will not be reliable.
- *
- * The arch code can provide optimized implementation by defining macros
- * for certain scalar sizes. F.e. provide this_cpu_add_2() to provide per
- * cpu atomic operations for 2 byte sized RMW actions. If arch code does
- * not provide operations for a scalar size then the fallback in the
- * generic code will be used.
- */
-
-# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
-# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
-# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
-# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(typeof(pcp))(val))
-# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
-# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
-# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
-# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
-# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
-#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(typeof(pcp))(val))
-#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
-#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
-# define this_cpu_xchg(pcp, nval) \
- __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
-# define this_cpu_cmpxchg(pcp, oval, nval) \
- __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
-
-/*
- * cmpxchg_double replaces two adjacent scalars at once. The first
- * two parameters are per cpu variables which have to be of the same
- * size. A truth value is returned to indicate success or failure
- * (since a double register result is difficult to handle). There is
- * very limited hardware support for these operations, so only certain
- * sizes may work.
- */
-# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
- __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
-
-/*
- * Generic percpu operations for contexts where we do not want to do
- * any checks for preemptiosn.
- *
- * If there is no other protection through preempt disable and/or
- * disabling interupts then one of these RMW operations can show unexpected
- * behavior because the execution thread was rescheduled on another processor
- * or an interrupt occurred and the same percpu variable was modified from
- * the interrupt context.
- */
-# define raw_cpu_read(pcp) __pcpu_size_call_return(raw_cpu_read_, (pcp))
-# define raw_cpu_write(pcp, val) __pcpu_size_call(raw_cpu_write_, (pcp), (val))
-# define raw_cpu_add(pcp, val) __pcpu_size_call(raw_cpu_add_, (pcp), (val))
-# define raw_cpu_sub(pcp, val) raw_cpu_add((pcp), -(val))
-# define raw_cpu_inc(pcp) raw_cpu_add((pcp), 1)
-# define raw_cpu_dec(pcp) raw_cpu_sub((pcp), 1)
-# define raw_cpu_and(pcp, val) __pcpu_size_call(raw_cpu_and_, (pcp), (val))
-# define raw_cpu_or(pcp, val) __pcpu_size_call(raw_cpu_or_, (pcp), (val))
-# define raw_cpu_add_return(pcp, val) \
- __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)
-#define raw_cpu_sub_return(pcp, val) raw_cpu_add_return(pcp, -(typeof(pcp))(val))
-#define raw_cpu_inc_return(pcp) raw_cpu_add_return(pcp, 1)
-#define raw_cpu_dec_return(pcp) raw_cpu_add_return(pcp, -1)
-# define raw_cpu_xchg(pcp, nval) \
- __pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval)
-# define raw_cpu_cmpxchg(pcp, oval, nval) \
- __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)
-# define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
- __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
-
-/*
- * Generic percpu operations for context that are safe from preemption/interrupts.
- */
-# define __this_cpu_read(pcp) \
- (__this_cpu_preempt_check("read"),__pcpu_size_call_return(raw_cpu_read_, (pcp)))
-
-# define __this_cpu_write(pcp, val) \
-do { __this_cpu_preempt_check("write"); \
- __pcpu_size_call(raw_cpu_write_, (pcp), (val)); \
-} while (0)
-
-# define __this_cpu_add(pcp, val) \
-do { __this_cpu_preempt_check("add"); \
- __pcpu_size_call(raw_cpu_add_, (pcp), (val)); \
-} while (0)
-
-# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(typeof(pcp))(val))
-# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
-# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
-
-# define __this_cpu_and(pcp, val) \
-do { __this_cpu_preempt_check("and"); \
- __pcpu_size_call(raw_cpu_and_, (pcp), (val)); \
-} while (0)
-
-# define __this_cpu_or(pcp, val) \
-do { __this_cpu_preempt_check("or"); \
- __pcpu_size_call(raw_cpu_or_, (pcp), (val)); \
-} while (0)
-
-# define __this_cpu_add_return(pcp, val) \
- (__this_cpu_preempt_check("add_return"),__pcpu_size_call_return2(raw_cpu_add_return_, pcp, val))
-
-#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val))
-#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1)
-#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1)
-
-# define __this_cpu_xchg(pcp, nval) \
- (__this_cpu_preempt_check("xchg"),__pcpu_size_call_return2(raw_cpu_xchg_, (pcp), nval))
-
-# define __this_cpu_cmpxchg(pcp, oval, nval) \
- (__this_cpu_preempt_check("cmpxchg"),__pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval))
-
-# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
- (__this_cpu_preempt_check("cmpxchg_double"),__pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)))
-
#endif /* __LINUX_PERCPU_H */