Commit 3b8ed91d authored by Tejun Heo's avatar Tejun Heo

percpu: reorganize include/linux/percpu-defs.h

Reorganize for better readability.

* Accessor definitions are collected into one place and SMP and UP now
  define them in the same order.

* Definitions are layered when possible - e.g. per_cpu() is now
  defined in terms of this_cpu_ptr().

* Rather pointless comment dropped.

* per_cpu(), __raw_get_cpu_var() and __get_cpu_var() are defined in a
  way which can be shared between SMP and UP and moved out of
  CONFIG_SMP blocks.

This patch doesn't introduce any functional difference.
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
parent 9defda18
......@@ -215,14 +215,7 @@
RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)); \
})
/*
* A percpu variable may point to a discarded regions. The following are
* established ways to produce a usable pointer from the percpu variable
* offset.
*/
#define per_cpu(var, cpu) \
(*SHIFT_PERCPU_PTR(&(var), per_cpu_offset(cpu)))
#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
#define raw_cpu_ptr(ptr) arch_raw_cpu_ptr(ptr)
#ifdef CONFIG_DEBUG_PREEMPT
......@@ -231,9 +224,6 @@
#define this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
#endif
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
#define __raw_get_cpu_var(var) (*raw_cpu_ptr(&(var)))
#else /* CONFIG_SMP */
#define VERIFY_PERCPU_PTR(__p) ({ \
......@@ -241,14 +231,16 @@
(typeof(*(__p)) __kernel __force *)(__p); \
})
#define per_cpu(var, cpu) (*((void)(cpu), VERIFY_PERCPU_PTR(&(var))))
#define __get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
#define __raw_get_cpu_var(var) (*VERIFY_PERCPU_PTR(&(var)))
#define this_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
#define raw_cpu_ptr(ptr) this_cpu_ptr(ptr)
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
#define raw_cpu_ptr(ptr) per_cpu_ptr(ptr, 0)
#define this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
#endif /* CONFIG_SMP */
#define per_cpu(var, cpu) (*per_cpu_ptr(&(var), cpu))
#define __raw_get_cpu_var(var) (*raw_cpu_ptr(&(var)))
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
/* keep until we have removed all uses of __this_cpu_ptr */
#define __this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
......@@ -278,11 +270,5 @@
preempt_enable(); \
} while (0)
#ifdef CONFIG_SMP
#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
#else
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
#endif
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_PERCPU_DEFS_H */
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