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#ifndef _KERNEL_EVENTS_INTERNAL_H
#define _KERNEL_EVENTS_INTERNAL_H
#define RING_BUFFER_WRITABLE 0x01
struct ring_buffer {
atomic_t refcount;
struct rcu_head rcu_head;
#ifdef CONFIG_PERF_USE_VMALLOC
struct work_struct work;
int page_order; /* allocation order */
#endif
int nr_pages; /* nr of data pages */
int writable; /* are we writable */
atomic_t poll; /* POLL_ for wakeups */
local_t head; /* write position */
local_t nest; /* nested writers */
local_t events; /* event limit */
local_t wakeup; /* wakeup stamp */
local_t lost; /* nr records lost */
long watermark; /* wakeup watermark */
struct perf_event_mmap_page *user_page;
void *data_pages[0];
};
extern void rb_free(struct ring_buffer *rb);
extern struct ring_buffer *
rb_alloc(int nr_pages, long watermark, int cpu, int flags);
extern void perf_event_wakeup(struct perf_event *event);
extern void
perf_event_header__init_id(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event);
extern void
perf_event__output_id_sample(struct perf_event *event,
struct perf_output_handle *handle,
struct perf_sample_data *sample);
extern struct page *
perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
#ifdef CONFIG_PERF_USE_VMALLOC
/*
* Back perf_mmap() with vmalloc memory.
*
* Required for architectures that have d-cache aliasing issues.
*/
static inline int page_order(struct ring_buffer *rb)
{
return rb->page_order;
}
#else
static inline int page_order(struct ring_buffer *rb)
{
return 0;
}
#endif
static unsigned long perf_data_size(struct ring_buffer *rb)
{
return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
}
static inline void
__output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len)
{
do {
unsigned long size = min_t(unsigned long, handle->size, len);
memcpy(handle->addr, buf, size);
len -= size;
handle->addr += size;
buf += size;
handle->size -= size;
if (!handle->size) {
struct ring_buffer *rb = handle->rb;
handle->page++;
handle->page &= rb->nr_pages - 1;
handle->addr = rb->data_pages[handle->page];
handle->size = PAGE_SIZE << page_order(rb);
}
} while (len);
}
#endif /* _KERNEL_EVENTS_INTERNAL_H */
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