Line data Source code
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 :
13 : struct 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 :
61 : extern void rb_free(struct perf_buffer *rb);
62 :
63 0 : static inline void rb_free_rcu(struct rcu_head *rcu_head)
64 : {
65 0 : struct perf_buffer *rb;
66 :
67 0 : rb = container_of(rcu_head, struct perf_buffer, rcu_head);
68 0 : rb_free(rb);
69 0 : }
70 :
71 0 : static inline void rb_toggle_paused(struct perf_buffer *rb, bool pause)
72 : {
73 0 : if (!pause && rb->nr_pages)
74 0 : rb->paused = 0;
75 : else
76 0 : rb->paused = 1;
77 : }
78 :
79 : extern struct perf_buffer *
80 : rb_alloc(int nr_pages, long watermark, int cpu, int flags);
81 : extern void perf_event_wakeup(struct perf_event *event);
82 : extern int rb_alloc_aux(struct perf_buffer *rb, struct perf_event *event,
83 : pgoff_t pgoff, int nr_pages, long watermark, int flags);
84 : extern void rb_free_aux(struct perf_buffer *rb);
85 : extern struct perf_buffer *ring_buffer_get(struct perf_event *event);
86 : extern void ring_buffer_put(struct perf_buffer *rb);
87 :
88 0 : static inline bool rb_has_aux(struct perf_buffer *rb)
89 : {
90 0 : return !!rb->aux_nr_pages;
91 : }
92 :
93 : void perf_event_aux_event(struct perf_event *event, unsigned long head,
94 : unsigned long size, u64 flags);
95 :
96 : extern struct page *
97 : perf_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 :
106 : static inline int page_order(struct perf_buffer *rb)
107 : {
108 : return rb->page_order;
109 : }
110 :
111 : #else
112 :
113 0 : static inline int page_order(struct perf_buffer *rb)
114 : {
115 0 : return 0;
116 : }
117 : #endif
118 :
119 0 : static inline unsigned long perf_data_size(struct perf_buffer *rb)
120 : {
121 0 : return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
122 : }
123 :
124 0 : static inline unsigned long perf_aux_size(struct perf_buffer *rb)
125 : {
126 0 : 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) \
157 : static inline unsigned long \
158 : func_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 :
162 : static inline unsigned long
163 0 : __output_custom(struct perf_output_handle *handle, perf_copy_f copy_func,
164 : const void *buf, unsigned long len)
165 : {
166 0 : unsigned long orig_len = len;
167 0 : __DEFINE_OUTPUT_COPY_BODY(false, copy_func, handle->addr, buf,
168 : orig_len - len, size)
169 : }
170 :
171 : static inline unsigned long
172 0 : memcpy_common(void *dst, const void *src, unsigned long n)
173 : {
174 0 : memcpy(dst, src, n);
175 0 : return 0;
176 : }
177 :
178 0 : DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
179 :
180 : static inline unsigned long
181 0 : memcpy_skip(void *dst, const void *src, unsigned long n)
182 : {
183 0 : return 0;
184 : }
185 :
186 0 : DEFINE_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 :
191 : static inline unsigned long
192 : arch_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 :
204 0 : DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
205 :
206 0 : static inline int get_recursion_context(int *recursion)
207 : {
208 0 : unsigned int pc = preempt_count();
209 0 : unsigned char rctx = 0;
210 :
211 0 : rctx += !!(pc & (NMI_MASK));
212 0 : rctx += !!(pc & (NMI_MASK | HARDIRQ_MASK));
213 0 : rctx += !!(pc & (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET));
214 :
215 0 : if (recursion[rctx])
216 : return -1;
217 :
218 0 : recursion[rctx]++;
219 0 : barrier();
220 :
221 0 : return rctx;
222 : }
223 :
224 0 : static inline void put_recursion_context(int *recursion, int rctx)
225 : {
226 0 : barrier();
227 0 : recursion[rctx]--;
228 : }
229 :
230 : #ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
231 0 : static inline bool arch_perf_have_user_stack_dump(void)
232 : {
233 0 : return true;
234 : }
235 :
236 : #define perf_user_stack_pointer(regs) user_stack_pointer(regs)
237 : #else
238 : static 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 */
|