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1#ifndef _KERNEL_EVENTS_INTERNAL_H
2#define _KERNEL_EVENTS_INTERNAL_H
3
4#include <linux/hardirq.h>
5
6/* Buffer handling */
7
8#define RING_BUFFER_WRITABLE 0x01
9
10struct ring_buffer {
11 atomic_t refcount;
12 struct rcu_head rcu_head;
13#ifdef CONFIG_PERF_USE_VMALLOC
14 struct work_struct work;
15 int page_order; /* allocation order */
16#endif
17 int nr_pages; /* nr of data pages */
18 int writable; /* are we writable */
19
20 atomic_t poll; /* POLL_ for wakeups */
21
22 local_t head; /* write position */
23 local_t nest; /* nested writers */
24 local_t events; /* event limit */
25 local_t wakeup; /* wakeup stamp */
26 local_t lost; /* nr records lost */
27
28 long watermark; /* wakeup watermark */
29 /* poll crap */
30 spinlock_t event_lock;
31 struct list_head event_list;
32
33 struct perf_event_mmap_page *user_page;
34 void *data_pages[0];
35};
36
37extern void rb_free(struct ring_buffer *rb);
38extern struct ring_buffer *
39rb_alloc(int nr_pages, long watermark, int cpu, int flags);
40extern void perf_event_wakeup(struct perf_event *event);
41
42extern void
43perf_event_header__init_id(struct perf_event_header *header,
44 struct perf_sample_data *data,
45 struct perf_event *event);
46extern void
47perf_event__output_id_sample(struct perf_event *event,
48 struct perf_output_handle *handle,
49 struct perf_sample_data *sample);
50
51extern struct page *
52perf_mmap_to_page(struct ring_buffer *rb, unsigned long pgoff);
53
54#ifdef CONFIG_PERF_USE_VMALLOC
55/*
56 * Back perf_mmap() with vmalloc memory.
57 *
58 * Required for architectures that have d-cache aliasing issues.
59 */
60
61static inline int page_order(struct ring_buffer *rb)
62{
63 return rb->page_order;
64}
65
66#else
67
68static inline int page_order(struct ring_buffer *rb)
69{
70 return 0;
71}
72#endif
73
74static inline unsigned long perf_data_size(struct ring_buffer *rb)
75{
76 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
77}
78
79static inline void
80__output_copy(struct perf_output_handle *handle,
81 const void *buf, unsigned int len)
82{
83 do {
84 unsigned long size = min_t(unsigned long, handle->size, len);
85
86 memcpy(handle->addr, buf, size);
87
88 len -= size;
89 handle->addr += size;
90 buf += size;
91 handle->size -= size;
92 if (!handle->size) {
93 struct ring_buffer *rb = handle->rb;
94
95 handle->page++;
96 handle->page &= rb->nr_pages - 1;
97 handle->addr = rb->data_pages[handle->page];
98 handle->size = PAGE_SIZE << page_order(rb);
99 }
100 } while (len);
101}
102
103/* Callchain handling */
104extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);
105extern int get_callchain_buffers(void);
106extern void put_callchain_buffers(void);
107
108static inline int get_recursion_context(int *recursion)
109{
110 int rctx;
111
112 if (in_nmi())
113 rctx = 3;
114 else if (in_irq())
115 rctx = 2;
116 else if (in_softirq())
117 rctx = 1;
118 else
119 rctx = 0;
120
121 if (recursion[rctx])
122 return -1;
123
124 recursion[rctx]++;
125 barrier();
126
127 return rctx;
128}
129
130static inline void put_recursion_context(int *recursion, int rctx)
131{
132 barrier();
133 recursion[rctx]--;
134}
135
136#endif /* _KERNEL_EVENTS_INTERNAL_H */
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 unsigned long perf_data_size(struct perf_buffer *rb)
120{
121 return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
122}
123
124static inline unsigned long perf_aux_size(struct perf_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 perf_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 unsigned int pc = preempt_count();
209 unsigned char rctx = 0;
210
211 rctx += !!(pc & (NMI_MASK));
212 rctx += !!(pc & (NMI_MASK | HARDIRQ_MASK));
213 rctx += !!(pc & (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET));
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 */