1
2#ifndef _KERNEL_EVENTS_INTERNAL_H
3#define _KERNEL_EVENTS_INTERNAL_H
4
5#include <linux/hardirq.h>
6#include <linux/uaccess.h>
7#include <linux/refcount.h>
8
9
10
11#define RING_BUFFER_WRITABLE 0x01
12
13struct ring_buffer {
14 refcount_t refcount;
15 struct rcu_head rcu_head;
16#ifdef CONFIG_PERF_USE_VMALLOC
17 struct work_struct work;
18 int page_order;
19#endif
20 int nr_pages;
21 int overwrite;
22 int paused;
23
24 atomic_t poll;
25
26 local_t head;
27 unsigned int nest;
28 local_t events;
29 local_t wakeup;
30 local_t lost;
31
32 long watermark;
33 long aux_watermark;
34
35 spinlock_t event_lock;
36 struct list_head event_list;
37
38 atomic_t mmap_count;
39 unsigned long mmap_locked;
40 struct user_struct *mmap_user;
41
42
43 long aux_head;
44 unsigned int aux_nest;
45 long aux_wakeup;
46 unsigned long aux_pgoff;
47 int aux_nr_pages;
48 int aux_overwrite;
49 atomic_t aux_mmap_count;
50 unsigned long aux_mmap_locked;
51 void (*free_aux)(void *);
52 refcount_t aux_refcount;
53 int aux_in_sampling;
54 void **aux_pages;
55 void *aux_priv;
56
57 struct perf_event_mmap_page *user_page;
58 void *data_pages[0];
59};
60
61extern void rb_free(struct ring_buffer *rb);
62
63static inline void rb_free_rcu(struct rcu_head *rcu_head)
64{
65 struct ring_buffer *rb;
66
67 rb = container_of(rcu_head, struct ring_buffer, rcu_head);
68 rb_free(rb);
69}
70
71static inline void rb_toggle_paused(struct ring_buffer *rb, bool pause)
72{
73 if (!pause && rb->nr_pages)
74 rb->paused = 0;
75 else
76 rb->paused = 1;
77}
78
79extern struct ring_buffer *
80rb_alloc(int nr_pages, long watermark, int cpu, int flags);
81extern void perf_event_wakeup(struct perf_event *event);
82extern int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
83 pgoff_t pgoff, int nr_pages, long watermark, int flags);
84extern void rb_free_aux(struct ring_buffer *rb);
85extern struct ring_buffer *ring_buffer_get(struct perf_event *event);
86extern void ring_buffer_put(struct ring_buffer *rb);
87
88static inline bool rb_has_aux(struct ring_buffer *rb)
89{
90 return !!rb->aux_nr_pages;
91}
92
93void perf_event_aux_event(struct perf_event *event, unsigned long head,
94 unsigned long size, u64 flags);
95
96extern struct page *
97perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
98
99#ifdef CONFIG_PERF_USE_VMALLOC
100
101
102
103
104
105
106static inline int page_order(struct ring_buffer *rb)
107{
108 return rb->page_order;
109}
110
111#else
112
113static inline int page_order(struct ring_buffer *rb)
114{
115 return 0;
116}
117#endif
118
119static inline unsigned long perf_data_size(struct ring_buffer *rb)
120{
121 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
122}
123
124static inline unsigned long perf_aux_size(struct ring_buffer *rb)
125{
126 return rb->aux_nr_pages << PAGE_SHIFT;
127}
128
129#define __DEFINE_OUTPUT_COPY_BODY(advance_buf, memcpy_func, ...) \
130{ \
131 unsigned long size, written; \
132 \
133 do { \
134 size = min(handle->size, len); \
135 written = memcpy_func(__VA_ARGS__); \
136 written = size - written; \
137 \
138 len -= written; \
139 handle->addr += written; \
140 if (advance_buf) \
141 buf += written; \
142 handle->size -= written; \
143 if (!handle->size) { \
144 struct ring_buffer *rb = handle->rb; \
145 \
146 handle->page++; \
147 handle->page &= rb->nr_pages - 1; \
148 handle->addr = rb->data_pages[handle->page]; \
149 handle->size = PAGE_SIZE << page_order(rb); \
150 } \
151 } while (len && written == size); \
152 \
153 return len; \
154}
155
156#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \
157static inline unsigned long \
158func_name(struct perf_output_handle *handle, \
159 const void *buf, unsigned long len) \
160__DEFINE_OUTPUT_COPY_BODY(true, memcpy_func, handle->addr, buf, size)
161
162static inline unsigned long
163__output_custom(struct perf_output_handle *handle, perf_copy_f copy_func,
164 const void *buf, unsigned long len)
165{
166 unsigned long orig_len = len;
167 __DEFINE_OUTPUT_COPY_BODY(false, copy_func, handle->addr, buf,
168 orig_len - len, size)
169}
170
171static inline unsigned long
172memcpy_common(void *dst, const void *src, unsigned long n)
173{
174 memcpy(dst, src, n);
175 return 0;
176}
177
178DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
179
180static inline unsigned long
181memcpy_skip(void *dst, const void *src, unsigned long n)
182{
183 return 0;
184}
185
186DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip)
187
188#ifndef arch_perf_out_copy_user
189#define arch_perf_out_copy_user arch_perf_out_copy_user
190
191static inline unsigned long
192arch_perf_out_copy_user(void *dst, const void *src, unsigned long n)
193{
194 unsigned long ret;
195
196 pagefault_disable();
197 ret = __copy_from_user_inatomic(dst, src, n);
198 pagefault_enable();
199
200 return ret;
201}
202#endif
203
204DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
205
206static inline int get_recursion_context(int *recursion)
207{
208 int rctx;
209
210 if (unlikely(in_nmi()))
211 rctx = 3;
212 else if (in_irq())
213 rctx = 2;
214 else if (in_softirq())
215 rctx = 1;
216 else
217 rctx = 0;
218
219 if (recursion[rctx])
220 return -1;
221
222 recursion[rctx]++;
223 barrier();
224
225 return rctx;
226}
227
228static inline void put_recursion_context(int *recursion, int rctx)
229{
230 barrier();
231 recursion[rctx]--;
232}
233
234#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
235static inline bool arch_perf_have_user_stack_dump(void)
236{
237 return true;
238}
239
240#define perf_user_stack_pointer(regs) user_stack_pointer(regs)
241#else
242static inline bool arch_perf_have_user_stack_dump(void)
243{
244 return false;
245}
246
247#define perf_user_stack_pointer(regs) 0
248#endif
249
250#endif
251