xref: /openbmc/linux/tools/perf/util/ordered-events.c (revision c819e2cf)
1 #include <linux/list.h>
2 #include <linux/compiler.h>
3 #include <linux/string.h>
4 #include "ordered-events.h"
5 #include "evlist.h"
6 #include "session.h"
7 #include "asm/bug.h"
8 #include "debug.h"
9 
10 #define pr_N(n, fmt, ...) \
11 	eprintf(n, debug_ordered_events, fmt, ##__VA_ARGS__)
12 
13 #define pr(fmt, ...) pr_N(1, pr_fmt(fmt), ##__VA_ARGS__)
14 
15 static void queue_event(struct ordered_events *oe, struct ordered_event *new)
16 {
17 	struct ordered_event *last = oe->last;
18 	u64 timestamp = new->timestamp;
19 	struct list_head *p;
20 
21 	++oe->nr_events;
22 	oe->last = new;
23 
24 	pr_oe_time2(timestamp, "queue_event nr_events %u\n", oe->nr_events);
25 
26 	if (!last) {
27 		list_add(&new->list, &oe->events);
28 		oe->max_timestamp = timestamp;
29 		return;
30 	}
31 
32 	/*
33 	 * last event might point to some random place in the list as it's
34 	 * the last queued event. We expect that the new event is close to
35 	 * this.
36 	 */
37 	if (last->timestamp <= timestamp) {
38 		while (last->timestamp <= timestamp) {
39 			p = last->list.next;
40 			if (p == &oe->events) {
41 				list_add_tail(&new->list, &oe->events);
42 				oe->max_timestamp = timestamp;
43 				return;
44 			}
45 			last = list_entry(p, struct ordered_event, list);
46 		}
47 		list_add_tail(&new->list, &last->list);
48 	} else {
49 		while (last->timestamp > timestamp) {
50 			p = last->list.prev;
51 			if (p == &oe->events) {
52 				list_add(&new->list, &oe->events);
53 				return;
54 			}
55 			last = list_entry(p, struct ordered_event, list);
56 		}
57 		list_add(&new->list, &last->list);
58 	}
59 }
60 
61 static union perf_event *__dup_event(struct ordered_events *oe,
62 				     union perf_event *event)
63 {
64 	union perf_event *new_event = NULL;
65 
66 	if (oe->cur_alloc_size < oe->max_alloc_size) {
67 		new_event = memdup(event, event->header.size);
68 		if (new_event)
69 			oe->cur_alloc_size += event->header.size;
70 	}
71 
72 	return new_event;
73 }
74 
75 static union perf_event *dup_event(struct ordered_events *oe,
76 				   union perf_event *event)
77 {
78 	return oe->copy_on_queue ? __dup_event(oe, event) : event;
79 }
80 
81 static void free_dup_event(struct ordered_events *oe, union perf_event *event)
82 {
83 	if (oe->copy_on_queue) {
84 		oe->cur_alloc_size -= event->header.size;
85 		free(event);
86 	}
87 }
88 
89 #define MAX_SAMPLE_BUFFER	(64 * 1024 / sizeof(struct ordered_event))
90 static struct ordered_event *alloc_event(struct ordered_events *oe,
91 					 union perf_event *event)
92 {
93 	struct list_head *cache = &oe->cache;
94 	struct ordered_event *new = NULL;
95 	union perf_event *new_event;
96 
97 	new_event = dup_event(oe, event);
98 	if (!new_event)
99 		return NULL;
100 
101 	if (!list_empty(cache)) {
102 		new = list_entry(cache->next, struct ordered_event, list);
103 		list_del(&new->list);
104 	} else if (oe->buffer) {
105 		new = oe->buffer + oe->buffer_idx;
106 		if (++oe->buffer_idx == MAX_SAMPLE_BUFFER)
107 			oe->buffer = NULL;
108 	} else if (oe->cur_alloc_size < oe->max_alloc_size) {
109 		size_t size = MAX_SAMPLE_BUFFER * sizeof(*new);
110 
111 		oe->buffer = malloc(size);
112 		if (!oe->buffer) {
113 			free_dup_event(oe, new_event);
114 			return NULL;
115 		}
116 
117 		pr("alloc size %" PRIu64 "B (+%zu), max %" PRIu64 "B\n",
118 		   oe->cur_alloc_size, size, oe->max_alloc_size);
119 
120 		oe->cur_alloc_size += size;
121 		list_add(&oe->buffer->list, &oe->to_free);
122 
123 		/* First entry is abused to maintain the to_free list. */
124 		oe->buffer_idx = 2;
125 		new = oe->buffer + 1;
126 	} else {
127 		pr("allocation limit reached %" PRIu64 "B\n", oe->max_alloc_size);
128 	}
129 
130 	new->event = new_event;
131 	return new;
132 }
133 
134 struct ordered_event *
135 ordered_events__new(struct ordered_events *oe, u64 timestamp,
136 		    union perf_event *event)
137 {
138 	struct ordered_event *new;
139 
140 	new = alloc_event(oe, event);
141 	if (new) {
142 		new->timestamp = timestamp;
143 		queue_event(oe, new);
144 	}
145 
146 	return new;
147 }
148 
149 void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event)
150 {
151 	list_move(&event->list, &oe->cache);
152 	oe->nr_events--;
153 	free_dup_event(oe, event->event);
154 }
155 
156 static int __ordered_events__flush(struct perf_session *s,
157 				   struct perf_tool *tool)
158 {
159 	struct ordered_events *oe = &s->ordered_events;
160 	struct list_head *head = &oe->events;
161 	struct ordered_event *tmp, *iter;
162 	struct perf_sample sample;
163 	u64 limit = oe->next_flush;
164 	u64 last_ts = oe->last ? oe->last->timestamp : 0ULL;
165 	bool show_progress = limit == ULLONG_MAX;
166 	struct ui_progress prog;
167 	int ret;
168 
169 	if (!tool->ordered_events || !limit)
170 		return 0;
171 
172 	if (show_progress)
173 		ui_progress__init(&prog, oe->nr_events, "Processing time ordered events...");
174 
175 	list_for_each_entry_safe(iter, tmp, head, list) {
176 		if (session_done())
177 			return 0;
178 
179 		if (iter->timestamp > limit)
180 			break;
181 
182 		ret = perf_evlist__parse_sample(s->evlist, iter->event, &sample);
183 		if (ret)
184 			pr_err("Can't parse sample, err = %d\n", ret);
185 		else {
186 			ret = perf_session__deliver_event(s, iter->event, &sample, tool,
187 							  iter->file_offset);
188 			if (ret)
189 				return ret;
190 		}
191 
192 		ordered_events__delete(oe, iter);
193 		oe->last_flush = iter->timestamp;
194 
195 		if (show_progress)
196 			ui_progress__update(&prog, 1);
197 	}
198 
199 	if (list_empty(head))
200 		oe->last = NULL;
201 	else if (last_ts <= limit)
202 		oe->last = list_entry(head->prev, struct ordered_event, list);
203 
204 	return 0;
205 }
206 
207 int ordered_events__flush(struct perf_session *s, struct perf_tool *tool,
208 			  enum oe_flush how)
209 {
210 	struct ordered_events *oe = &s->ordered_events;
211 	static const char * const str[] = {
212 		"NONE",
213 		"FINAL",
214 		"ROUND",
215 		"HALF ",
216 	};
217 	int err;
218 
219 	switch (how) {
220 	case OE_FLUSH__FINAL:
221 		oe->next_flush = ULLONG_MAX;
222 		break;
223 
224 	case OE_FLUSH__HALF:
225 	{
226 		struct ordered_event *first, *last;
227 		struct list_head *head = &oe->events;
228 
229 		first = list_entry(head->next, struct ordered_event, list);
230 		last = oe->last;
231 
232 		/* Warn if we are called before any event got allocated. */
233 		if (WARN_ONCE(!last || list_empty(head), "empty queue"))
234 			return 0;
235 
236 		oe->next_flush  = first->timestamp;
237 		oe->next_flush += (last->timestamp - first->timestamp) / 2;
238 		break;
239 	}
240 
241 	case OE_FLUSH__ROUND:
242 	case OE_FLUSH__NONE:
243 	default:
244 		break;
245 	};
246 
247 	pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush PRE  %s, nr_events %u\n",
248 		   str[how], oe->nr_events);
249 	pr_oe_time(oe->max_timestamp, "max_timestamp\n");
250 
251 	err = __ordered_events__flush(s, tool);
252 
253 	if (!err) {
254 		if (how == OE_FLUSH__ROUND)
255 			oe->next_flush = oe->max_timestamp;
256 
257 		oe->last_flush_type = how;
258 	}
259 
260 	pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush POST %s, nr_events %u\n",
261 		   str[how], oe->nr_events);
262 	pr_oe_time(oe->last_flush, "last_flush\n");
263 
264 	return err;
265 }
266 
267 void ordered_events__init(struct ordered_events *oe)
268 {
269 	INIT_LIST_HEAD(&oe->events);
270 	INIT_LIST_HEAD(&oe->cache);
271 	INIT_LIST_HEAD(&oe->to_free);
272 	oe->max_alloc_size = (u64) -1;
273 	oe->cur_alloc_size = 0;
274 }
275 
276 void ordered_events__free(struct ordered_events *oe)
277 {
278 	while (!list_empty(&oe->to_free)) {
279 		struct ordered_event *event;
280 
281 		event = list_entry(oe->to_free.next, struct ordered_event, list);
282 		list_del(&event->list);
283 		free_dup_event(oe, event->event);
284 		free(event);
285 	}
286 }
287