xref: /openbmc/linux/tools/perf/util/expr.c (revision 2427f03f)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <stdbool.h>
3 #include <assert.h>
4 #include <errno.h>
5 #include <stdlib.h>
6 #include <string.h>
7 #include "metricgroup.h"
8 #include "cpumap.h"
9 #include "cputopo.h"
10 #include "debug.h"
11 #include "expr.h"
12 #include "expr-bison.h"
13 #include "expr-flex.h"
14 #include "smt.h"
15 #include <linux/err.h>
16 #include <linux/kernel.h>
17 #include <linux/zalloc.h>
18 #include <ctype.h>
19 #include <math.h>
20 
21 #ifdef PARSER_DEBUG
22 extern int expr_debug;
23 #endif
24 
25 struct expr_id_data {
26 	union {
27 		struct {
28 			double val;
29 			int source_count;
30 		} val;
31 		struct {
32 			double val;
33 			const char *metric_name;
34 			const char *metric_expr;
35 		} ref;
36 	};
37 
38 	enum {
39 		/* Holding a double value. */
40 		EXPR_ID_DATA__VALUE,
41 		/* Reference to another metric. */
42 		EXPR_ID_DATA__REF,
43 		/* A reference but the value has been computed. */
44 		EXPR_ID_DATA__REF_VALUE,
45 	} kind;
46 };
47 
48 static size_t key_hash(const void *key, void *ctx __maybe_unused)
49 {
50 	const char *str = (const char *)key;
51 	size_t hash = 0;
52 
53 	while (*str != '\0') {
54 		hash *= 31;
55 		hash += *str;
56 		str++;
57 	}
58 	return hash;
59 }
60 
61 static bool key_equal(const void *key1, const void *key2,
62 		    void *ctx __maybe_unused)
63 {
64 	return !strcmp((const char *)key1, (const char *)key2);
65 }
66 
67 struct hashmap *ids__new(void)
68 {
69 	struct hashmap *hash;
70 
71 	hash = hashmap__new(key_hash, key_equal, NULL);
72 	if (IS_ERR(hash))
73 		return NULL;
74 	return hash;
75 }
76 
77 void ids__free(struct hashmap *ids)
78 {
79 	struct hashmap_entry *cur;
80 	size_t bkt;
81 
82 	if (ids == NULL)
83 		return;
84 
85 	hashmap__for_each_entry(ids, cur, bkt) {
86 		free((char *)cur->key);
87 		free(cur->value);
88 	}
89 
90 	hashmap__free(ids);
91 }
92 
93 int ids__insert(struct hashmap *ids, const char *id)
94 {
95 	struct expr_id_data *data_ptr = NULL, *old_data = NULL;
96 	char *old_key = NULL;
97 	int ret;
98 
99 	ret = hashmap__set(ids, id, data_ptr,
100 			   (const void **)&old_key, (void **)&old_data);
101 	if (ret)
102 		free(data_ptr);
103 	free(old_key);
104 	free(old_data);
105 	return ret;
106 }
107 
108 struct hashmap *ids__union(struct hashmap *ids1, struct hashmap *ids2)
109 {
110 	size_t bkt;
111 	struct hashmap_entry *cur;
112 	int ret;
113 	struct expr_id_data *old_data = NULL;
114 	char *old_key = NULL;
115 
116 	if (!ids1)
117 		return ids2;
118 
119 	if (!ids2)
120 		return ids1;
121 
122 	if (hashmap__size(ids1) <  hashmap__size(ids2)) {
123 		struct hashmap *tmp = ids1;
124 
125 		ids1 = ids2;
126 		ids2 = tmp;
127 	}
128 	hashmap__for_each_entry(ids2, cur, bkt) {
129 		ret = hashmap__set(ids1, cur->key, cur->value,
130 				(const void **)&old_key, (void **)&old_data);
131 		free(old_key);
132 		free(old_data);
133 
134 		if (ret) {
135 			hashmap__free(ids1);
136 			hashmap__free(ids2);
137 			return NULL;
138 		}
139 	}
140 	hashmap__free(ids2);
141 	return ids1;
142 }
143 
144 /* Caller must make sure id is allocated */
145 int expr__add_id(struct expr_parse_ctx *ctx, const char *id)
146 {
147 	return ids__insert(ctx->ids, id);
148 }
149 
150 /* Caller must make sure id is allocated */
151 int expr__add_id_val(struct expr_parse_ctx *ctx, const char *id, double val)
152 {
153 	return expr__add_id_val_source_count(ctx, id, val, /*source_count=*/1);
154 }
155 
156 /* Caller must make sure id is allocated */
157 int expr__add_id_val_source_count(struct expr_parse_ctx *ctx, const char *id,
158 				  double val, int source_count)
159 {
160 	struct expr_id_data *data_ptr = NULL, *old_data = NULL;
161 	char *old_key = NULL;
162 	int ret;
163 
164 	data_ptr = malloc(sizeof(*data_ptr));
165 	if (!data_ptr)
166 		return -ENOMEM;
167 	data_ptr->val.val = val;
168 	data_ptr->val.source_count = source_count;
169 	data_ptr->kind = EXPR_ID_DATA__VALUE;
170 
171 	ret = hashmap__set(ctx->ids, id, data_ptr,
172 			   (const void **)&old_key, (void **)&old_data);
173 	if (ret)
174 		free(data_ptr);
175 	free(old_key);
176 	free(old_data);
177 	return ret;
178 }
179 
180 int expr__add_ref(struct expr_parse_ctx *ctx, struct metric_ref *ref)
181 {
182 	struct expr_id_data *data_ptr = NULL, *old_data = NULL;
183 	char *old_key = NULL;
184 	char *name, *p;
185 	int ret;
186 
187 	data_ptr = zalloc(sizeof(*data_ptr));
188 	if (!data_ptr)
189 		return -ENOMEM;
190 
191 	name = strdup(ref->metric_name);
192 	if (!name) {
193 		free(data_ptr);
194 		return -ENOMEM;
195 	}
196 
197 	/*
198 	 * The jevents tool converts all metric expressions
199 	 * to lowercase, including metric references, hence
200 	 * we need to add lowercase name for metric, so it's
201 	 * properly found.
202 	 */
203 	for (p = name; *p; p++)
204 		*p = tolower(*p);
205 
206 	/*
207 	 * Intentionally passing just const char pointers,
208 	 * originally from 'struct pmu_event' object.
209 	 * We don't need to change them, so there's no
210 	 * need to create our own copy.
211 	 */
212 	data_ptr->ref.metric_name = ref->metric_name;
213 	data_ptr->ref.metric_expr = ref->metric_expr;
214 	data_ptr->kind = EXPR_ID_DATA__REF;
215 
216 	ret = hashmap__set(ctx->ids, name, data_ptr,
217 			   (const void **)&old_key, (void **)&old_data);
218 	if (ret)
219 		free(data_ptr);
220 
221 	pr_debug2("adding ref metric %s: %s\n",
222 		  ref->metric_name, ref->metric_expr);
223 
224 	free(old_key);
225 	free(old_data);
226 	return ret;
227 }
228 
229 int expr__get_id(struct expr_parse_ctx *ctx, const char *id,
230 		 struct expr_id_data **data)
231 {
232 	return hashmap__find(ctx->ids, id, (void **)data) ? 0 : -1;
233 }
234 
235 bool expr__subset_of_ids(struct expr_parse_ctx *haystack,
236 			 struct expr_parse_ctx *needles)
237 {
238 	struct hashmap_entry *cur;
239 	size_t bkt;
240 	struct expr_id_data *data;
241 
242 	hashmap__for_each_entry(needles->ids, cur, bkt) {
243 		if (expr__get_id(haystack, cur->key, &data))
244 			return false;
245 	}
246 	return true;
247 }
248 
249 
250 int expr__resolve_id(struct expr_parse_ctx *ctx, const char *id,
251 		     struct expr_id_data **datap)
252 {
253 	struct expr_id_data *data;
254 
255 	if (expr__get_id(ctx, id, datap) || !*datap) {
256 		pr_debug("%s not found\n", id);
257 		return -1;
258 	}
259 
260 	data = *datap;
261 
262 	switch (data->kind) {
263 	case EXPR_ID_DATA__VALUE:
264 		pr_debug2("lookup(%s): val %f\n", id, data->val.val);
265 		break;
266 	case EXPR_ID_DATA__REF:
267 		pr_debug2("lookup(%s): ref metric name %s\n", id,
268 			data->ref.metric_name);
269 		pr_debug("processing metric: %s ENTRY\n", id);
270 		data->kind = EXPR_ID_DATA__REF_VALUE;
271 		if (expr__parse(&data->ref.val, ctx, data->ref.metric_expr)) {
272 			pr_debug("%s failed to count\n", id);
273 			return -1;
274 		}
275 		pr_debug("processing metric: %s EXIT: %f\n", id, data->ref.val);
276 		break;
277 	case EXPR_ID_DATA__REF_VALUE:
278 		pr_debug2("lookup(%s): ref val %f metric name %s\n", id,
279 			data->ref.val, data->ref.metric_name);
280 		break;
281 	default:
282 		assert(0);  /* Unreachable. */
283 	}
284 
285 	return 0;
286 }
287 
288 void expr__del_id(struct expr_parse_ctx *ctx, const char *id)
289 {
290 	struct expr_id_data *old_val = NULL;
291 	char *old_key = NULL;
292 
293 	hashmap__delete(ctx->ids, id,
294 			(const void **)&old_key, (void **)&old_val);
295 	free(old_key);
296 	free(old_val);
297 }
298 
299 struct expr_parse_ctx *expr__ctx_new(void)
300 {
301 	struct expr_parse_ctx *ctx;
302 
303 	ctx = malloc(sizeof(struct expr_parse_ctx));
304 	if (!ctx)
305 		return NULL;
306 
307 	ctx->ids = hashmap__new(key_hash, key_equal, NULL);
308 	if (IS_ERR(ctx->ids)) {
309 		free(ctx);
310 		return NULL;
311 	}
312 	ctx->runtime = 0;
313 
314 	return ctx;
315 }
316 
317 void expr__ctx_clear(struct expr_parse_ctx *ctx)
318 {
319 	struct hashmap_entry *cur;
320 	size_t bkt;
321 
322 	hashmap__for_each_entry(ctx->ids, cur, bkt) {
323 		free((char *)cur->key);
324 		free(cur->value);
325 	}
326 	hashmap__clear(ctx->ids);
327 }
328 
329 void expr__ctx_free(struct expr_parse_ctx *ctx)
330 {
331 	struct hashmap_entry *cur;
332 	size_t bkt;
333 
334 	hashmap__for_each_entry(ctx->ids, cur, bkt) {
335 		free((char *)cur->key);
336 		free(cur->value);
337 	}
338 	hashmap__free(ctx->ids);
339 	free(ctx);
340 }
341 
342 static int
343 __expr__parse(double *val, struct expr_parse_ctx *ctx, const char *expr,
344 	      bool compute_ids)
345 {
346 	struct expr_scanner_ctx scanner_ctx = {
347 		.runtime = ctx->runtime,
348 	};
349 	YY_BUFFER_STATE buffer;
350 	void *scanner;
351 	int ret;
352 
353 	pr_debug2("parsing metric: %s\n", expr);
354 
355 	ret = expr_lex_init_extra(&scanner_ctx, &scanner);
356 	if (ret)
357 		return ret;
358 
359 	buffer = expr__scan_string(expr, scanner);
360 
361 #ifdef PARSER_DEBUG
362 	expr_debug = 1;
363 	expr_set_debug(1, scanner);
364 #endif
365 
366 	ret = expr_parse(val, ctx, compute_ids, scanner);
367 
368 	expr__flush_buffer(buffer, scanner);
369 	expr__delete_buffer(buffer, scanner);
370 	expr_lex_destroy(scanner);
371 	return ret;
372 }
373 
374 int expr__parse(double *final_val, struct expr_parse_ctx *ctx,
375 		const char *expr)
376 {
377 	return __expr__parse(final_val, ctx, expr, /*compute_ids=*/false) ? -1 : 0;
378 }
379 
380 int expr__find_ids(const char *expr, const char *one,
381 		   struct expr_parse_ctx *ctx)
382 {
383 	int ret = __expr__parse(NULL, ctx, expr, /*compute_ids=*/true);
384 
385 	if (one)
386 		expr__del_id(ctx, one);
387 
388 	return ret;
389 }
390 
391 double expr_id_data__value(const struct expr_id_data *data)
392 {
393 	if (data->kind == EXPR_ID_DATA__VALUE)
394 		return data->val.val;
395 	assert(data->kind == EXPR_ID_DATA__REF_VALUE);
396 	return data->ref.val;
397 }
398 
399 double expr_id_data__source_count(const struct expr_id_data *data)
400 {
401 	assert(data->kind == EXPR_ID_DATA__VALUE);
402 	return data->val.source_count;
403 }
404 
405 double expr__get_literal(const char *literal)
406 {
407 	static struct cpu_topology *topology;
408 	double result = NAN;
409 
410 	if (!strcasecmp("#smt_on", literal)) {
411 		result = smt_on() > 0 ? 1.0 : 0.0;
412 		goto out;
413 	}
414 
415 	if (!strcmp("#num_cpus", literal)) {
416 		result = cpu__max_present_cpu().cpu;
417 		goto out;
418 	}
419 
420 	/*
421 	 * Assume that topology strings are consistent, such as CPUs "0-1"
422 	 * wouldn't be listed as "0,1", and so after deduplication the number of
423 	 * these strings gives an indication of the number of packages, dies,
424 	 * etc.
425 	 */
426 	if (!topology) {
427 		topology = cpu_topology__new();
428 		if (!topology) {
429 			pr_err("Error creating CPU topology");
430 			goto out;
431 		}
432 	}
433 	if (!strcmp("#num_packages", literal)) {
434 		result = topology->package_cpus_lists;
435 		goto out;
436 	}
437 	if (!strcmp("#num_dies", literal)) {
438 		result = topology->die_cpus_lists;
439 		goto out;
440 	}
441 	if (!strcmp("#num_cores", literal)) {
442 		result = topology->core_cpus_lists;
443 		goto out;
444 	}
445 
446 	pr_err("Unrecognized literal '%s'", literal);
447 out:
448 	pr_debug2("literal: %s = %f\n", literal, result);
449 	return result;
450 }
451