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1/* SPDX-License-Identifier: GPL-2.0 */
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/* Buffer handling */
10
11#define RING_BUFFER_WRITABLE 0x01
12
13struct perf_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; /* allocation order */
19#endif
20 int nr_pages; /* nr of data pages */
21 int overwrite; /* can overwrite itself */
22 int paused; /* can write into ring buffer */
23
24 atomic_t poll; /* POLL_ for wakeups */
25
26 local_t head; /* write position */
27 unsigned int nest; /* nested writers */
28 local_t events; /* event limit */
29 local_t wakeup; /* wakeup stamp */
30 local_t lost; /* nr records lost */
31
32 long watermark; /* wakeup watermark */
33 long aux_watermark;
34 /* poll crap */
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 /* AUX area */
43 long aux_head;
44 unsigned int aux_nest;
45 long aux_wakeup; /* last aux_watermark boundary crossed by aux_head */
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[];
59};
60
61extern void rb_free(struct perf_buffer *rb);
62
63static inline void rb_free_rcu(struct rcu_head *rcu_head)
64{
65 struct perf_buffer *rb;
66
67 rb = container_of(rcu_head, struct perf_buffer, rcu_head);
68 rb_free(rb);
69}
70
71static inline void rb_toggle_paused(struct perf_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 perf_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 perf_buffer *rb, struct perf_event *event,
83 pgoff_t pgoff, int nr_pages, long watermark, int flags);
84extern void rb_free_aux(struct perf_buffer *rb);
85extern struct perf_buffer *ring_buffer_get(struct perf_event *event);
86extern void ring_buffer_put(struct perf_buffer *rb);
87
88static inline bool rb_has_aux(struct perf_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 perf_buffer *rb, unsigned long pgoff);
98
99#ifdef CONFIG_PERF_USE_VMALLOC
100/*
101 * Back perf_mmap() with vmalloc memory.
102 *
103 * Required for architectures that have d-cache aliasing issues.
104 */
105
106static inline int page_order(struct perf_buffer *rb)
107{
108 return rb->page_order;
109}
110
111#else
112
113static inline int page_order(struct perf_buffer *rb)
114{
115 return 0;
116}
117#endif
118
119static inline int data_page_nr(struct perf_buffer *rb)
120{
121 return rb->nr_pages << page_order(rb);
122}
123
124static inline unsigned long perf_data_size(struct perf_buffer *rb)
125{
126 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
127}
128
129static inline unsigned long perf_aux_size(struct perf_buffer *rb)
130{
131 return rb->aux_nr_pages << PAGE_SHIFT;
132}
133
134#define __DEFINE_OUTPUT_COPY_BODY(advance_buf, memcpy_func, ...) \
135{ \
136 unsigned long size, written; \
137 \
138 do { \
139 size = min(handle->size, len); \
140 written = memcpy_func(__VA_ARGS__); \
141 written = size - written; \
142 \
143 len -= written; \
144 handle->addr += written; \
145 if (advance_buf) \
146 buf += written; \
147 handle->size -= written; \
148 if (!handle->size) { \
149 struct perf_buffer *rb = handle->rb; \
150 \
151 handle->page++; \
152 handle->page &= rb->nr_pages - 1; \
153 handle->addr = rb->data_pages[handle->page]; \
154 handle->size = PAGE_SIZE << page_order(rb); \
155 } \
156 } while (len && written == size); \
157 \
158 return len; \
159}
160
161#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \
162static inline unsigned long \
163func_name(struct perf_output_handle *handle, \
164 const void *buf, unsigned long len) \
165__DEFINE_OUTPUT_COPY_BODY(true, memcpy_func, handle->addr, buf, size)
166
167static inline unsigned long
168__output_custom(struct perf_output_handle *handle, perf_copy_f copy_func,
169 const void *buf, unsigned long len)
170{
171 unsigned long orig_len = len;
172 __DEFINE_OUTPUT_COPY_BODY(false, copy_func, handle->addr, buf,
173 orig_len - len, size)
174}
175
176static inline unsigned long
177memcpy_common(void *dst, const void *src, unsigned long n)
178{
179 memcpy(dst, src, n);
180 return 0;
181}
182
183DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
184
185static inline unsigned long
186memcpy_skip(void *dst, const void *src, unsigned long n)
187{
188 return 0;
189}
190
191DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip)
192
193#ifndef arch_perf_out_copy_user
194#define arch_perf_out_copy_user arch_perf_out_copy_user
195
196static inline unsigned long
197arch_perf_out_copy_user(void *dst, const void *src, unsigned long n)
198{
199 unsigned long ret;
200
201 pagefault_disable();
202 ret = __copy_from_user_inatomic(dst, src, n);
203 pagefault_enable();
204
205 return ret;
206}
207#endif
208
209DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
210
211static inline int get_recursion_context(int *recursion)
212{
213 unsigned char rctx = interrupt_context_level();
214
215 if (recursion[rctx])
216 return -1;
217
218 recursion[rctx]++;
219 barrier();
220
221 return rctx;
222}
223
224static inline void put_recursion_context(int *recursion, int rctx)
225{
226 barrier();
227 recursion[rctx]--;
228}
229
230#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
231static inline bool arch_perf_have_user_stack_dump(void)
232{
233 return true;
234}
235
236#define perf_user_stack_pointer(regs) user_stack_pointer(regs)
237#else
238static inline bool arch_perf_have_user_stack_dump(void)
239{
240 return false;
241}
242
243#define perf_user_stack_pointer(regs) 0
244#endif /* CONFIG_HAVE_PERF_USER_STACK_DUMP */
245
246#endif /* _KERNEL_EVENTS_INTERNAL_H */
1#ifndef _KERNEL_EVENTS_INTERNAL_H
2#define _KERNEL_EVENTS_INTERNAL_H
3
4#define RING_BUFFER_WRITABLE 0x01
5
6struct ring_buffer {
7 atomic_t refcount;
8 struct rcu_head rcu_head;
9#ifdef CONFIG_PERF_USE_VMALLOC
10 struct work_struct work;
11 int page_order; /* allocation order */
12#endif
13 int nr_pages; /* nr of data pages */
14 int writable; /* are we writable */
15
16 atomic_t poll; /* POLL_ for wakeups */
17
18 local_t head; /* write position */
19 local_t nest; /* nested writers */
20 local_t events; /* event limit */
21 local_t wakeup; /* wakeup stamp */
22 local_t lost; /* nr records lost */
23
24 long watermark; /* wakeup watermark */
25
26 struct perf_event_mmap_page *user_page;
27 void *data_pages[0];
28};
29
30extern void rb_free(struct ring_buffer *rb);
31extern struct ring_buffer *
32rb_alloc(int nr_pages, long watermark, int cpu, int flags);
33extern void perf_event_wakeup(struct perf_event *event);
34
35extern void
36perf_event_header__init_id(struct perf_event_header *header,
37 struct perf_sample_data *data,
38 struct perf_event *event);
39extern void
40perf_event__output_id_sample(struct perf_event *event,
41 struct perf_output_handle *handle,
42 struct perf_sample_data *sample);
43
44extern struct page *
45perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
46
47#ifdef CONFIG_PERF_USE_VMALLOC
48/*
49 * Back perf_mmap() with vmalloc memory.
50 *
51 * Required for architectures that have d-cache aliasing issues.
52 */
53
54static inline int page_order(struct ring_buffer *rb)
55{
56 return rb->page_order;
57}
58
59#else
60
61static inline int page_order(struct ring_buffer *rb)
62{
63 return 0;
64}
65#endif
66
67static unsigned long perf_data_size(struct ring_buffer *rb)
68{
69 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
70}
71
72static inline void
73__output_copy(struct perf_output_handle *handle,
74 const void *buf, unsigned int len)
75{
76 do {
77 unsigned long size = min_t(unsigned long, handle->size, len);
78
79 memcpy(handle->addr, buf, size);
80
81 len -= size;
82 handle->addr += size;
83 buf += size;
84 handle->size -= size;
85 if (!handle->size) {
86 struct ring_buffer *rb = handle->rb;
87
88 handle->page++;
89 handle->page &= rb->nr_pages - 1;
90 handle->addr = rb->data_pages[handle->page];
91 handle->size = PAGE_SIZE << page_order(rb);
92 }
93 } while (len);
94}
95
96#endif /* _KERNEL_EVENTS_INTERNAL_H */