x86: Define early read-mostly per-cpu macros

Some read-mostly per-cpu data may need to be declared or defined
early, so it can be initialized and accessed before per_cpu
areas are allocated.

Only the data that resides in the per_cpu areas should be
read-mostly, as there is little benefit in optimizing cache
lines on initialization.

Signed-off-by: Ido Yariv <ido@wizery.com>
[ Added the missing declarations in !SMP code. ]
Signed-off-by: Vlad Zolotarov <vlad@scalemp.com>
Acked-by: Shai Fultheim <shai@scalemp.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/46188571.ddB8aVQYWo@vlad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ido Yariv 2012-06-11 12:56:45 +03:00 committed by Ingo Molnar
parent b0a4c6f2e3
commit c35f77417e

View File

@ -551,6 +551,12 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off);
{ [0 ... NR_CPUS-1] = _initvalue }; \
__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue; \
__typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
{ [0 ... NR_CPUS-1] = _initvalue }; \
__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
EXPORT_PER_CPU_SYMBOL(_name)
@ -559,6 +565,11 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off);
extern __typeof__(_type) *_name##_early_ptr; \
extern __typeof__(_type) _name##_early_map[]
#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
DECLARE_PER_CPU_READ_MOSTLY(_type, _name); \
extern __typeof__(_type) *_name##_early_ptr; \
extern __typeof__(_type) _name##_early_map[]
#define early_per_cpu_ptr(_name) (_name##_early_ptr)
#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
#define early_per_cpu(_name, _cpu) \
@ -570,12 +581,18 @@ DECLARE_PER_CPU(unsigned long, this_cpu_off);
#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
DEFINE_PER_CPU(_type, _name) = _initvalue
#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
EXPORT_PER_CPU_SYMBOL(_name)
#define DECLARE_EARLY_PER_CPU(_type, _name) \
DECLARE_PER_CPU(_type, _name)
#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
#define early_per_cpu_ptr(_name) NULL
/* no early_per_cpu_map() */