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 void **aux_pages;
54 void *aux_priv;
55
56 struct perf_event_mmap_page *user_page;
57 void *data_pages[0];
58};
59
60extern void rb_free(struct ring_buffer *rb);
61
62static inline void rb_free_rcu(struct rcu_head *rcu_head)
63{
64 struct ring_buffer *rb;
65
66 rb = container_of(rcu_head, struct ring_buffer, rcu_head);
67 rb_free(rb);
68}
69
70static inline void rb_toggle_paused(struct ring_buffer *rb, bool pause)
71{
72 if (!pause && rb->nr_pages)
73 rb->paused = 0;
74 else
75 rb->paused = 1;
76}
77
78extern struct ring_buffer *
79rb_alloc(int nr_pages, long watermark, int cpu, int flags);
80extern void perf_event_wakeup(struct perf_event *event);
81extern int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
82 pgoff_t pgoff, int nr_pages, long watermark, int flags);
83extern void rb_free_aux(struct ring_buffer *rb);
84extern struct ring_buffer *ring_buffer_get(struct perf_event *event);
85extern void ring_buffer_put(struct ring_buffer *rb);
86
87static inline bool rb_has_aux(struct ring_buffer *rb)
88{
89 return !!rb->aux_nr_pages;
90}
91
92void perf_event_aux_event(struct perf_event *event, unsigned long head,
93 unsigned long size, u64 flags);
94
95extern struct page *
96perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
97
98#ifdef CONFIG_PERF_USE_VMALLOC
99
100
101
102
103
104
105static inline int page_order(struct ring_buffer *rb)
106{
107 return rb->page_order;
108}
109
110#else
111
112static inline int page_order(struct ring_buffer *rb)
113{
114 return 0;
115}
116#endif
117
118static inline unsigned long perf_data_size(struct ring_buffer *rb)
119{
120 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
121}
122
123static inline unsigned long perf_aux_size(struct ring_buffer *rb)
124{
125 return rb->aux_nr_pages << PAGE_SHIFT;
126}
127
128#define __DEFINE_OUTPUT_COPY_BODY(advance_buf, memcpy_func, ...) \
129{ \
130 unsigned long size, written; \
131 \
132 do { \
133 size = min(handle->size, len); \
134 written = memcpy_func(__VA_ARGS__); \
135 written = size - written; \
136 \
137 len -= written; \
138 handle->addr += written; \
139 if (advance_buf) \
140 buf += written; \
141 handle->size -= written; \
142 if (!handle->size) { \
143 struct ring_buffer *rb = handle->rb; \
144 \
145 handle->page++; \
146 handle->page &= rb->nr_pages - 1; \
147 handle->addr = rb->data_pages[handle->page]; \
148 handle->size = PAGE_SIZE << page_order(rb); \
149 } \
150 } while (len && written == size); \
151 \
152 return len; \
153}
154
155#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \
156static inline unsigned long \
157func_name(struct perf_output_handle *handle, \
158 const void *buf, unsigned long len) \
159__DEFINE_OUTPUT_COPY_BODY(true, memcpy_func, handle->addr, buf, size)
160
161static inline unsigned long
162__output_custom(struct perf_output_handle *handle, perf_copy_f copy_func,
163 const void *buf, unsigned long len)
164{
165 unsigned long orig_len = len;
166 __DEFINE_OUTPUT_COPY_BODY(false, copy_func, handle->addr, buf,
167 orig_len - len, size)
168}
169
170static inline unsigned long
171memcpy_common(void *dst, const void *src, unsigned long n)
172{
173 memcpy(dst, src, n);
174 return 0;
175}
176
177DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
178
179static inline unsigned long
180memcpy_skip(void *dst, const void *src, unsigned long n)
181{
182 return 0;
183}
184
185DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip)
186
187#ifndef arch_perf_out_copy_user
188#define arch_perf_out_copy_user arch_perf_out_copy_user
189
190static inline unsigned long
191arch_perf_out_copy_user(void *dst, const void *src, unsigned long n)
192{
193 unsigned long ret;
194
195 pagefault_disable();
196 ret = __copy_from_user_inatomic(dst, src, n);
197 pagefault_enable();
198
199 return ret;
200}
201#endif
202
203DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
204
205static inline int get_recursion_context(int *recursion)
206{
207 int rctx;
208
209 if (unlikely(in_nmi()))
210 rctx = 3;
211 else if (in_irq())
212 rctx = 2;
213 else if (in_softirq())
214 rctx = 1;
215 else
216 rctx = 0;
217
218 if (recursion[rctx])
219 return -1;
220
221 recursion[rctx]++;
222 barrier();
223
224 return rctx;
225}
226
227static inline void put_recursion_context(int *recursion, int rctx)
228{
229 barrier();
230 recursion[rctx]--;
231}
232
233#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
234static inline bool arch_perf_have_user_stack_dump(void)
235{
236 return true;
237}
238
239#define perf_user_stack_pointer(regs) user_stack_pointer(regs)
240#else
241static inline bool arch_perf_have_user_stack_dump(void)
242{
243 return false;
244}
245
246#define perf_user_stack_pointer(regs) 0
247#endif
248
249#endif
250
