b324215190
Instead of allocating a fix sized array of NR_CPUS pointers for percpu_data, we can use nr_cpu_ids, which is generally < NR_CPUS. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
133 lines
3.9 KiB
C
133 lines
3.9 KiB
C
#ifndef __LINUX_PERCPU_H
|
|
#define __LINUX_PERCPU_H
|
|
|
|
#include <linux/preempt.h>
|
|
#include <linux/slab.h> /* For kmalloc() */
|
|
#include <linux/smp.h>
|
|
#include <linux/string.h> /* For memset() */
|
|
#include <linux/cpumask.h>
|
|
|
|
#include <asm/percpu.h>
|
|
|
|
#ifdef CONFIG_SMP
|
|
#define DEFINE_PER_CPU(type, name) \
|
|
__attribute__((__section__(".data.percpu"))) \
|
|
PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
|
|
|
|
#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
|
|
__attribute__((__section__(".data.percpu.shared_aligned"))) \
|
|
PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name \
|
|
____cacheline_aligned_in_smp
|
|
#else
|
|
#define DEFINE_PER_CPU(type, name) \
|
|
PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
|
|
|
|
#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
|
|
DEFINE_PER_CPU(type, name)
|
|
#endif
|
|
|
|
#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
|
|
#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
|
|
|
|
/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
|
|
#ifndef PERCPU_ENOUGH_ROOM
|
|
#ifdef CONFIG_MODULES
|
|
#define PERCPU_MODULE_RESERVE 8192
|
|
#else
|
|
#define PERCPU_MODULE_RESERVE 0
|
|
#endif
|
|
|
|
#define PERCPU_ENOUGH_ROOM \
|
|
(__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
|
|
#endif /* PERCPU_ENOUGH_ROOM */
|
|
|
|
/*
|
|
* Must be an lvalue. Since @var must be a simple identifier,
|
|
* we force a syntax error here if it isn't.
|
|
*/
|
|
#define get_cpu_var(var) (*({ \
|
|
extern int simple_identifier_##var(void); \
|
|
preempt_disable(); \
|
|
&__get_cpu_var(var); }))
|
|
#define put_cpu_var(var) preempt_enable()
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
struct percpu_data {
|
|
void *ptrs[1];
|
|
};
|
|
|
|
#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
|
|
/*
|
|
* Use this to get to a cpu's version of the per-cpu object dynamically
|
|
* allocated. Non-atomic access to the current CPU's version should
|
|
* probably be combined with get_cpu()/put_cpu().
|
|
*/
|
|
#define percpu_ptr(ptr, cpu) \
|
|
({ \
|
|
struct percpu_data *__p = __percpu_disguise(ptr); \
|
|
(__typeof__(ptr))__p->ptrs[(cpu)]; \
|
|
})
|
|
|
|
extern void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu);
|
|
extern void percpu_depopulate(void *__pdata, int cpu);
|
|
extern int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp,
|
|
cpumask_t *mask);
|
|
extern void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask);
|
|
extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask);
|
|
extern void percpu_free(void *__pdata);
|
|
|
|
#else /* CONFIG_SMP */
|
|
|
|
#define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
|
|
|
|
static inline void percpu_depopulate(void *__pdata, int cpu)
|
|
{
|
|
}
|
|
|
|
static inline void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask)
|
|
{
|
|
}
|
|
|
|
static inline void *percpu_populate(void *__pdata, size_t size, gfp_t gfp,
|
|
int cpu)
|
|
{
|
|
return percpu_ptr(__pdata, cpu);
|
|
}
|
|
|
|
static inline int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp,
|
|
cpumask_t *mask)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask)
|
|
{
|
|
return kzalloc(size, gfp);
|
|
}
|
|
|
|
static inline void percpu_free(void *__pdata)
|
|
{
|
|
kfree(__pdata);
|
|
}
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#define percpu_populate_mask(__pdata, size, gfp, mask) \
|
|
__percpu_populate_mask((__pdata), (size), (gfp), &(mask))
|
|
#define percpu_depopulate_mask(__pdata, mask) \
|
|
__percpu_depopulate_mask((__pdata), &(mask))
|
|
#define percpu_alloc_mask(size, gfp, mask) \
|
|
__percpu_alloc_mask((size), (gfp), &(mask))
|
|
|
|
#define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
|
|
|
|
/* (legacy) interface for use without CPU hotplug handling */
|
|
|
|
#define __alloc_percpu(size) percpu_alloc_mask((size), GFP_KERNEL, \
|
|
cpu_possible_map)
|
|
#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type))
|
|
#define free_percpu(ptr) percpu_free((ptr))
|
|
#define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu))
|
|
|
|
#endif /* __LINUX_PERCPU_H */
|