swh:1:snp:3c665ee4f67729f27f2e40193ab88e7298cf0fef
Tip revision: bfeffd155283772bbe78c6a05dec7c0128ee500c authored by Linus Torvalds on 07 January 2019, 01:08:20 UTC
Linux 5.0-rc1
Linux 5.0-rc1
Tip revision: bfeffd1
internal.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _KERNEL_EVENTS_INTERNAL_H
#define _KERNEL_EVENTS_INTERNAL_H
#include <linux/hardirq.h>
#include <linux/uaccess.h>
/* Buffer handling */
#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 overwrite; /* can overwrite itself */
int paused; /* can write into ring buffer */
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 */
long aux_watermark;
/* poll crap */
spinlock_t event_lock;
struct list_head event_list;
atomic_t mmap_count;
unsigned long mmap_locked;
struct user_struct *mmap_user;
/* AUX area */
long aux_head;
local_t aux_nest;
long aux_wakeup; /* last aux_watermark boundary crossed by aux_head */
unsigned long aux_pgoff;
int aux_nr_pages;
int aux_overwrite;
atomic_t aux_mmap_count;
unsigned long aux_mmap_locked;
void (*free_aux)(void *);
atomic_t aux_refcount;
void **aux_pages;
void *aux_priv;
struct perf_event_mmap_page *user_page;
void *data_pages[0];
};
extern void rb_free(struct ring_buffer *rb);
static inline void rb_free_rcu(struct rcu_head *rcu_head)
{
struct ring_buffer *rb;
rb = container_of(rcu_head, struct ring_buffer, rcu_head);
rb_free(rb);
}
static inline void rb_toggle_paused(struct ring_buffer *rb, bool pause)
{
if (!pause && rb->nr_pages)
rb->paused = 0;
else
rb->paused = 1;
}
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 int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
pgoff_t pgoff, int nr_pages, long watermark, int flags);
extern void rb_free_aux(struct ring_buffer *rb);
extern struct ring_buffer *ring_buffer_get(struct perf_event *event);
extern void ring_buffer_put(struct ring_buffer *rb);
static inline bool rb_has_aux(struct ring_buffer *rb)
{
return !!rb->aux_nr_pages;
}
void perf_event_aux_event(struct perf_event *event, unsigned long head,
unsigned long size, u64 flags);
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 inline unsigned long perf_data_size(struct ring_buffer *rb)
{
return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
}
static inline unsigned long perf_aux_size(struct ring_buffer *rb)
{
return rb->aux_nr_pages << PAGE_SHIFT;
}
#define __DEFINE_OUTPUT_COPY_BODY(advance_buf, memcpy_func, ...) \
{ \
unsigned long size, written; \
\
do { \
size = min(handle->size, len); \
written = memcpy_func(__VA_ARGS__); \
written = size - written; \
\
len -= written; \
handle->addr += written; \
if (advance_buf) \
buf += written; \
handle->size -= written; \
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 && written == size); \
\
return len; \
}
#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \
static inline unsigned long \
func_name(struct perf_output_handle *handle, \
const void *buf, unsigned long len) \
__DEFINE_OUTPUT_COPY_BODY(true, memcpy_func, handle->addr, buf, size)
static inline unsigned long
__output_custom(struct perf_output_handle *handle, perf_copy_f copy_func,
const void *buf, unsigned long len)
{
unsigned long orig_len = len;
__DEFINE_OUTPUT_COPY_BODY(false, copy_func, handle->addr, buf,
orig_len - len, size)
}
static inline unsigned long
memcpy_common(void *dst, const void *src, unsigned long n)
{
memcpy(dst, src, n);
return 0;
}
DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
static inline unsigned long
memcpy_skip(void *dst, const void *src, unsigned long n)
{
return 0;
}
DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip)
#ifndef arch_perf_out_copy_user
#define arch_perf_out_copy_user arch_perf_out_copy_user
static inline unsigned long
arch_perf_out_copy_user(void *dst, const void *src, unsigned long n)
{
unsigned long ret;
pagefault_disable();
ret = __copy_from_user_inatomic(dst, src, n);
pagefault_enable();
return ret;
}
#endif
DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
static inline int get_recursion_context(int *recursion)
{
int rctx;
if (unlikely(in_nmi()))
rctx = 3;
else if (in_irq())
rctx = 2;
else if (in_softirq())
rctx = 1;
else
rctx = 0;
if (recursion[rctx])
return -1;
recursion[rctx]++;
barrier();
return rctx;
}
static inline void put_recursion_context(int *recursion, int rctx)
{
barrier();
recursion[rctx]--;
}
#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
static inline bool arch_perf_have_user_stack_dump(void)
{
return true;
}
#define perf_user_stack_pointer(regs) user_stack_pointer(regs)
#else
static inline bool arch_perf_have_user_stack_dump(void)
{
return false;
}
#define perf_user_stack_pointer(regs) 0
#endif /* CONFIG_HAVE_PERF_USER_STACK_DUMP */
#endif /* _KERNEL_EVENTS_INTERNAL_H */