xref: /linux/tools/perf/util/lock-contention.h (revision 7685b334d1e4927cc73b62c65293ba65748d9c52)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef PERF_LOCK_CONTENTION_H
3 #define PERF_LOCK_CONTENTION_H
4 
5 #include <linux/list.h>
6 #include <linux/rbtree.h>
7 
8 struct lock_filter {
9 	int			nr_types;
10 	int			nr_addrs;
11 	int			nr_syms;
12 	int			nr_cgrps;
13 	int			nr_slabs;
14 	unsigned int		*types;
15 	unsigned long		*addrs;
16 	char			**syms;
17 	u64			*cgrps;
18 	char			**slabs;
19 };
20 
21 struct lock_stat {
22 	struct hlist_node	hash_entry;
23 	struct rb_node		rb;		/* used for sorting */
24 
25 	u64			addr;		/* address of lockdep_map, used as ID */
26 	char			*name;		/* for strcpy(), we cannot use const */
27 	u64			*callstack;
28 
29 	unsigned int		nr_acquire;
30 	unsigned int		nr_acquired;
31 	unsigned int		nr_contended;
32 	unsigned int		nr_release;
33 
34 	union {
35 		unsigned int	nr_readlock;
36 		unsigned int	flags;
37 	};
38 	unsigned int		nr_trylock;
39 
40 	/* these times are in nano sec. */
41 	u64                     avg_wait_time;
42 	u64			wait_time_total;
43 	u64			wait_time_min;
44 	u64			wait_time_max;
45 
46 	int			broken; /* flag of blacklist */
47 	int			combined;
48 };
49 
50 /*
51  * States of lock_seq_stat
52  *
53  * UNINITIALIZED is required for detecting first event of acquire.
54  * As the nature of lock events, there is no guarantee
55  * that the first event for the locks are acquire,
56  * it can be acquired, contended or release.
57  */
58 #define SEQ_STATE_UNINITIALIZED      0	       /* initial state */
59 #define SEQ_STATE_RELEASED	1
60 #define SEQ_STATE_ACQUIRING	2
61 #define SEQ_STATE_ACQUIRED	3
62 #define SEQ_STATE_READ_ACQUIRED	4
63 #define SEQ_STATE_CONTENDED	5
64 
65 /*
66  * MAX_LOCK_DEPTH
67  * Imported from include/linux/sched.h.
68  * Should this be synchronized?
69  */
70 #define MAX_LOCK_DEPTH 48
71 
72 /* based on kernel/lockdep.c */
73 #define LOCKHASH_BITS		12
74 #define LOCKHASH_SIZE		(1UL << LOCKHASH_BITS)
75 
76 extern struct hlist_head *lockhash_table;
77 
78 /*
79  * struct lock_seq_stat:
80  * Place to put on state of one lock sequence
81  * 1) acquire -> acquired -> release
82  * 2) acquire -> contended -> acquired -> release
83  * 3) acquire (with read or try) -> release
84  * 4) Are there other patterns?
85  */
86 struct lock_seq_stat {
87 	struct list_head        list;
88 	int			state;
89 	u64			prev_event_time;
90 	u64                     addr;
91 
92 	int                     read_count;
93 };
94 
95 struct thread_stat {
96 	struct rb_node		rb;
97 
98 	u32                     tid;
99 	struct list_head        seq_list;
100 };
101 
102 /*
103  * CONTENTION_STACK_DEPTH
104  * Number of stack trace entries to find callers
105  */
106 #define CONTENTION_STACK_DEPTH  8
107 
108 /*
109  * CONTENTION_STACK_SKIP
110  * Number of stack trace entries to skip when finding callers.
111  * The first few entries belong to the locking implementation itself.
112  */
113 #define CONTENTION_STACK_SKIP  4
114 
115 /*
116  * flags for lock:contention_begin
117  * Imported from include/trace/events/lock.h.
118  */
119 #define LCB_F_SPIN	(1U << 0)
120 #define LCB_F_READ	(1U << 1)
121 #define LCB_F_WRITE	(1U << 2)
122 #define LCB_F_RT	(1U << 3)
123 #define LCB_F_PERCPU	(1U << 4)
124 #define LCB_F_MUTEX	(1U << 5)
125 
126 struct evlist;
127 struct machine;
128 struct target;
129 
130 struct lock_contention_fails {
131 	int task;
132 	int stack;
133 	int time;
134 	int data;
135 };
136 
137 struct lock_contention {
138 	struct evlist *evlist;
139 	struct target *target;
140 	struct machine *machine;
141 	struct hlist_head *result;
142 	struct lock_filter *filters;
143 	struct lock_contention_fails fails;
144 	struct rb_root cgroups;
145 	unsigned long map_nr_entries;
146 	int max_stack;
147 	int stack_skip;
148 	int aggr_mode;
149 	int owner;
150 	int nr_filtered;
151 	bool save_callstack;
152 };
153 
154 struct option;
155 int parse_call_stack(const struct option *opt, const char *str, int unset);
156 bool needs_callstack(void);
157 
158 struct lock_stat *lock_stat_find(u64 addr);
159 struct lock_stat *lock_stat_findnew(u64 addr, const char *name, int flags);
160 
161 bool match_callstack_filter(struct machine *machine, u64 *callstack, int max_stack_depth);
162 
163 
164 #ifdef HAVE_BPF_SKEL
165 int lock_contention_prepare(struct lock_contention *con);
166 int lock_contention_start(void);
167 int lock_contention_stop(void);
168 int lock_contention_read(struct lock_contention *con);
169 int lock_contention_finish(struct lock_contention *con);
170 
171 #else  /* !HAVE_BPF_SKEL */
172 
173 static inline int lock_contention_prepare(struct lock_contention *con __maybe_unused)
174 {
175 	return 0;
176 }
177 
178 static inline int lock_contention_start(void) { return 0; }
179 static inline int lock_contention_stop(void) { return 0; }
180 static inline int lock_contention_finish(struct lock_contention *con __maybe_unused)
181 {
182 	return 0;
183 }
184 
185 static inline int lock_contention_read(struct lock_contention *con __maybe_unused)
186 {
187 	return 0;
188 }
189 
190 #endif  /* HAVE_BPF_SKEL */
191 
192 #endif  /* PERF_LOCK_CONTENTION_H */
193