xref: /linux/tools/perf/util/ordered-events.c (revision 30614cf34105c5b5b9a39c65a2ea32c58b03aa8e)
1 #include <linux/list.h>
2 #include <linux/compiler.h>
3 #include "ordered-events.h"
4 #include "evlist.h"
5 #include "session.h"
6 #include "asm/bug.h"
7 #include "debug.h"
8 
9 #define pr_N(n, fmt, ...) \
10 	eprintf(n, debug_ordered_events, fmt, ##__VA_ARGS__)
11 
12 #define pr(fmt, ...) pr_N(1, pr_fmt(fmt), ##__VA_ARGS__)
13 
14 static void queue_event(struct ordered_events *oe, struct ordered_event *new)
15 {
16 	struct ordered_event *last = oe->last;
17 	u64 timestamp = new->timestamp;
18 	struct list_head *p;
19 
20 	++oe->nr_events;
21 	oe->last = new;
22 
23 	pr_oe_time2(timestamp, "queue_event nr_events %u\n", oe->nr_events);
24 
25 	if (!last) {
26 		list_add(&new->list, &oe->events);
27 		oe->max_timestamp = timestamp;
28 		return;
29 	}
30 
31 	/*
32 	 * last event might point to some random place in the list as it's
33 	 * the last queued event. We expect that the new event is close to
34 	 * this.
35 	 */
36 	if (last->timestamp <= timestamp) {
37 		while (last->timestamp <= timestamp) {
38 			p = last->list.next;
39 			if (p == &oe->events) {
40 				list_add_tail(&new->list, &oe->events);
41 				oe->max_timestamp = timestamp;
42 				return;
43 			}
44 			last = list_entry(p, struct ordered_event, list);
45 		}
46 		list_add_tail(&new->list, &last->list);
47 	} else {
48 		while (last->timestamp > timestamp) {
49 			p = last->list.prev;
50 			if (p == &oe->events) {
51 				list_add(&new->list, &oe->events);
52 				return;
53 			}
54 			last = list_entry(p, struct ordered_event, list);
55 		}
56 		list_add(&new->list, &last->list);
57 	}
58 }
59 
60 #define MAX_SAMPLE_BUFFER	(64 * 1024 / sizeof(struct ordered_event))
61 static struct ordered_event *alloc_event(struct ordered_events *oe)
62 {
63 	struct list_head *cache = &oe->cache;
64 	struct ordered_event *new = NULL;
65 
66 	if (!list_empty(cache)) {
67 		new = list_entry(cache->next, struct ordered_event, list);
68 		list_del(&new->list);
69 	} else if (oe->buffer) {
70 		new = oe->buffer + oe->buffer_idx;
71 		if (++oe->buffer_idx == MAX_SAMPLE_BUFFER)
72 			oe->buffer = NULL;
73 	} else if (oe->cur_alloc_size < oe->max_alloc_size) {
74 		size_t size = MAX_SAMPLE_BUFFER * sizeof(*new);
75 
76 		oe->buffer = malloc(size);
77 		if (!oe->buffer)
78 			return NULL;
79 
80 		pr("alloc size %" PRIu64 "B (+%zu), max %" PRIu64 "B\n",
81 		   oe->cur_alloc_size, size, oe->max_alloc_size);
82 
83 		oe->cur_alloc_size += size;
84 		list_add(&oe->buffer->list, &oe->to_free);
85 
86 		/* First entry is abused to maintain the to_free list. */
87 		oe->buffer_idx = 2;
88 		new = oe->buffer + 1;
89 	} else {
90 		pr("allocation limit reached %" PRIu64 "B\n", oe->max_alloc_size);
91 	}
92 
93 	return new;
94 }
95 
96 struct ordered_event *
97 ordered_events__new(struct ordered_events *oe, u64 timestamp)
98 {
99 	struct ordered_event *new;
100 
101 	new = alloc_event(oe);
102 	if (new) {
103 		new->timestamp = timestamp;
104 		queue_event(oe, new);
105 	}
106 
107 	return new;
108 }
109 
110 void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event)
111 {
112 	list_move(&event->list, &oe->cache);
113 	oe->nr_events--;
114 }
115 
116 static int __ordered_events__flush(struct perf_session *s,
117 				   struct perf_tool *tool)
118 {
119 	struct ordered_events *oe = &s->ordered_events;
120 	struct list_head *head = &oe->events;
121 	struct ordered_event *tmp, *iter;
122 	struct perf_sample sample;
123 	u64 limit = oe->next_flush;
124 	u64 last_ts = oe->last ? oe->last->timestamp : 0ULL;
125 	bool show_progress = limit == ULLONG_MAX;
126 	struct ui_progress prog;
127 	int ret;
128 
129 	if (!tool->ordered_events || !limit)
130 		return 0;
131 
132 	if (show_progress)
133 		ui_progress__init(&prog, oe->nr_events, "Processing time ordered events...");
134 
135 	list_for_each_entry_safe(iter, tmp, head, list) {
136 		if (session_done())
137 			return 0;
138 
139 		if (iter->timestamp > limit)
140 			break;
141 
142 		ret = perf_evlist__parse_sample(s->evlist, iter->event, &sample);
143 		if (ret)
144 			pr_err("Can't parse sample, err = %d\n", ret);
145 		else {
146 			ret = perf_session__deliver_event(s, iter->event, &sample, tool,
147 							  iter->file_offset);
148 			if (ret)
149 				return ret;
150 		}
151 
152 		ordered_events__delete(oe, iter);
153 		oe->last_flush = iter->timestamp;
154 
155 		if (show_progress)
156 			ui_progress__update(&prog, 1);
157 	}
158 
159 	if (list_empty(head))
160 		oe->last = NULL;
161 	else if (last_ts <= limit)
162 		oe->last = list_entry(head->prev, struct ordered_event, list);
163 
164 	return 0;
165 }
166 
167 int ordered_events__flush(struct perf_session *s, struct perf_tool *tool,
168 			  enum oe_flush how)
169 {
170 	struct ordered_events *oe = &s->ordered_events;
171 	static const char * const str[] = {
172 		"NONE",
173 		"FINAL",
174 		"ROUND",
175 		"HALF ",
176 	};
177 	int err;
178 
179 	switch (how) {
180 	case OE_FLUSH__FINAL:
181 		oe->next_flush = ULLONG_MAX;
182 		break;
183 
184 	case OE_FLUSH__HALF:
185 	{
186 		struct ordered_event *first, *last;
187 		struct list_head *head = &oe->events;
188 
189 		first = list_entry(head->next, struct ordered_event, list);
190 		last = oe->last;
191 
192 		/* Warn if we are called before any event got allocated. */
193 		if (WARN_ONCE(!last || list_empty(head), "empty queue"))
194 			return 0;
195 
196 		oe->next_flush  = first->timestamp;
197 		oe->next_flush += (last->timestamp - first->timestamp) / 2;
198 		break;
199 	}
200 
201 	case OE_FLUSH__ROUND:
202 	case OE_FLUSH__NONE:
203 	default:
204 		break;
205 	};
206 
207 	pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush PRE  %s, nr_events %u\n",
208 		   str[how], oe->nr_events);
209 	pr_oe_time(oe->max_timestamp, "max_timestamp\n");
210 
211 	err = __ordered_events__flush(s, tool);
212 
213 	if (!err) {
214 		if (how == OE_FLUSH__ROUND)
215 			oe->next_flush = oe->max_timestamp;
216 
217 		oe->last_flush_type = how;
218 	}
219 
220 	pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush POST %s, nr_events %u\n",
221 		   str[how], oe->nr_events);
222 	pr_oe_time(oe->last_flush, "last_flush\n");
223 
224 	return err;
225 }
226 
227 void ordered_events__init(struct ordered_events *oe)
228 {
229 	INIT_LIST_HEAD(&oe->events);
230 	INIT_LIST_HEAD(&oe->cache);
231 	INIT_LIST_HEAD(&oe->to_free);
232 	oe->max_alloc_size = (u64) -1;
233 	oe->cur_alloc_size = 0;
234 }
235 
236 void ordered_events__free(struct ordered_events *oe)
237 {
238 	while (!list_empty(&oe->to_free)) {
239 		struct ordered_event *event;
240 
241 		event = list_entry(oe->to_free.next, struct ordered_event, list);
242 		list_del(&event->list);
243 		free(event);
244 	}
245 }
246