xref: /openbmc/linux/tools/perf/util/unwind.h (revision a9ebfc40)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __UNWIND_H
3 #define __UNWIND_H
4 
5 #include <linux/compiler.h>
6 #include <linux/types.h>
7 #include "util/map_symbol.h"
8 
9 struct maps;
10 struct perf_sample;
11 struct thread;
12 
13 struct unwind_entry {
14 	struct map_symbol ms;
15 	u64		  ip;
16 };
17 
18 typedef int (*unwind_entry_cb_t)(struct unwind_entry *entry, void *arg);
19 
20 struct unwind_libunwind_ops {
21 	int (*prepare_access)(struct maps *maps);
22 	void (*flush_access)(struct maps *maps);
23 	void (*finish_access)(struct maps *maps);
24 	int (*get_entries)(unwind_entry_cb_t cb, void *arg,
25 			   struct thread *thread,
26 			   struct perf_sample *data, int max_stack, bool best_effort);
27 };
28 
29 #ifdef HAVE_DWARF_UNWIND_SUPPORT
30 /*
31  * When best_effort is set, don't report errors and fail silently. This could
32  * be expanded in the future to be more permissive about things other than
33  * error messages.
34  */
35 int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
36 			struct thread *thread,
37 			struct perf_sample *data, int max_stack,
38 			bool best_effort);
39 /* libunwind specific */
40 #ifdef HAVE_LIBUNWIND_SUPPORT
41 #ifndef LIBUNWIND__ARCH_REG_ID
42 #define LIBUNWIND__ARCH_REG_ID(regnum) libunwind__arch_reg_id(regnum)
43 #endif
44 
45 int LIBUNWIND__ARCH_REG_ID(int regnum);
46 int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized);
47 void unwind__flush_access(struct maps *maps);
48 void unwind__finish_access(struct maps *maps);
49 #else
50 static inline int unwind__prepare_access(struct maps *maps __maybe_unused,
51 					 struct map *map __maybe_unused,
52 					 bool *initialized __maybe_unused)
53 {
54 	return 0;
55 }
56 
57 static inline void unwind__flush_access(struct maps *maps __maybe_unused) {}
58 static inline void unwind__finish_access(struct maps *maps __maybe_unused) {}
59 #endif
60 #else
61 static inline int
62 unwind__get_entries(unwind_entry_cb_t cb __maybe_unused,
63 		    void *arg __maybe_unused,
64 		    struct thread *thread __maybe_unused,
65 		    struct perf_sample *data __maybe_unused,
66 		    int max_stack __maybe_unused,
67 		    bool best_effort __maybe_unused)
68 {
69 	return 0;
70 }
71 
72 static inline int unwind__prepare_access(struct maps *maps __maybe_unused,
73 					 struct map *map __maybe_unused,
74 					 bool *initialized __maybe_unused)
75 {
76 	return 0;
77 }
78 
79 static inline void unwind__flush_access(struct maps *maps __maybe_unused) {}
80 static inline void unwind__finish_access(struct maps *maps __maybe_unused) {}
81 #endif /* HAVE_DWARF_UNWIND_SUPPORT */
82 #endif /* __UNWIND_H */
83