xref: /openbmc/linux/tools/perf/util/mmap.h (revision 09b35b41)
1 #ifndef __PERF_MMAP_H
2 #define __PERF_MMAP_H 1
3 
4 #include <linux/compiler.h>
5 #include <linux/refcount.h>
6 #include <linux/types.h>
7 #include <linux/ring_buffer.h>
8 #include <stdbool.h>
9 #include <pthread.h> // for cpu_set_t
10 #ifdef HAVE_AIO_SUPPORT
11 #include <aio.h>
12 #endif
13 #include "auxtrace.h"
14 #include "event.h"
15 
16 struct aiocb;
17 /**
18  * struct perf_mmap - perf's ring buffer mmap details
19  *
20  * @refcnt - e.g. code using PERF_EVENT_IOC_SET_OUTPUT to share this
21  */
22 struct perf_mmap {
23 	void		 *base;
24 	int		 mask;
25 	int		 fd;
26 	int		 cpu;
27 	refcount_t	 refcnt;
28 	u64		 prev;
29 	u64		 start;
30 	u64		 end;
31 	bool		 overwrite;
32 	struct auxtrace_mmap auxtrace_mmap;
33 	char		 event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8);
34 #ifdef HAVE_AIO_SUPPORT
35 	struct {
36 		void		 **data;
37 		struct aiocb	 *cblocks;
38 		struct aiocb	 **aiocb;
39 		int		 nr_cblocks;
40 	} aio;
41 #endif
42 	cpu_set_t	affinity_mask;
43 	u64		flush;
44 	void		*data;
45 	int		comp_level;
46 };
47 
48 /*
49  * State machine of bkw_mmap_state:
50  *
51  *                     .________________(forbid)_____________.
52  *                     |                                     V
53  * NOTREADY --(0)--> RUNNING --(1)--> DATA_PENDING --(2)--> EMPTY
54  *                     ^  ^              |   ^               |
55  *                     |  |__(forbid)____/   |___(forbid)___/|
56  *                     |                                     |
57  *                      \_________________(3)_______________/
58  *
59  * NOTREADY     : Backward ring buffers are not ready
60  * RUNNING      : Backward ring buffers are recording
61  * DATA_PENDING : We are required to collect data from backward ring buffers
62  * EMPTY        : We have collected data from backward ring buffers.
63  *
64  * (0): Setup backward ring buffer
65  * (1): Pause ring buffers for reading
66  * (2): Read from ring buffers
67  * (3): Resume ring buffers for recording
68  */
69 enum bkw_mmap_state {
70 	BKW_MMAP_NOTREADY,
71 	BKW_MMAP_RUNNING,
72 	BKW_MMAP_DATA_PENDING,
73 	BKW_MMAP_EMPTY,
74 };
75 
76 struct mmap_params {
77 	int prot, mask, nr_cblocks, affinity, flush, comp_level;
78 	struct auxtrace_mmap_params auxtrace_mp;
79 };
80 
81 int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd, int cpu);
82 void perf_mmap__munmap(struct perf_mmap *map);
83 
84 void perf_mmap__get(struct perf_mmap *map);
85 void perf_mmap__put(struct perf_mmap *map);
86 
87 void perf_mmap__consume(struct perf_mmap *map);
88 
89 static inline u64 perf_mmap__read_head(struct perf_mmap *mm)
90 {
91 	return ring_buffer_read_head(mm->base);
92 }
93 
94 static inline void perf_mmap__write_tail(struct perf_mmap *md, u64 tail)
95 {
96 	ring_buffer_write_tail(md->base, tail);
97 }
98 
99 union perf_event *perf_mmap__read_forward(struct perf_mmap *map);
100 
101 union perf_event *perf_mmap__read_event(struct perf_mmap *map);
102 
103 int perf_mmap__push(struct perf_mmap *md, void *to,
104 		    int push(struct perf_mmap *map, void *to, void *buf, size_t size));
105 
106 size_t perf_mmap__mmap_len(struct perf_mmap *map);
107 
108 int perf_mmap__read_init(struct perf_mmap *md);
109 void perf_mmap__read_done(struct perf_mmap *map);
110 #endif /*__PERF_MMAP_H */
111