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