xref: /dpdk/app/test-compress-perf/comp_perf_test_common.c (revision cf8c0c65514a12d4f326417f7cf54433338ed226)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2019 Intel Corporation
3  */
4 
5 #include <rte_malloc.h>
6 #include <rte_eal.h>
7 #include <rte_log.h>
8 #include <rte_compressdev.h>
9 
10 #include "comp_perf.h"
11 #include "comp_perf_options.h"
12 #include "comp_perf_test_throughput.h"
13 #include "comp_perf_test_cyclecount.h"
14 #include "comp_perf_test_common.h"
15 #include "comp_perf_test_verify.h"
16 
17 
18 #define DIV_CEIL(a, b)  ((a) / (b) + ((a) % (b) != 0))
19 
20 struct cperf_buffer_info {
21 	uint16_t total_segments;
22 	uint16_t segment_sz;
23 	uint16_t last_segment_sz;
24 	uint32_t total_buffs;	      /*number of buffers = number of ops*/
25 	uint16_t segments_per_buff;
26 	uint16_t segments_per_last_buff;
27 	size_t input_data_sz;
28 };
29 
30 static struct cperf_buffer_info buffer_info;
31 
32 int
param_range_check(uint16_t size,const struct rte_param_log2_range * range)33 param_range_check(uint16_t size, const struct rte_param_log2_range *range)
34 {
35 	unsigned int next_size;
36 
37 	/* Check lower/upper bounds */
38 	if (size < range->min)
39 		return -1;
40 
41 	if (size > range->max)
42 		return -1;
43 
44 	/* If range is actually only one value, size is correct */
45 	if (range->increment == 0)
46 		return 0;
47 
48 	/* Check if value is one of the supported sizes */
49 	for (next_size = range->min; next_size <= range->max;
50 			next_size += range->increment)
51 		if (size == next_size)
52 			return 0;
53 
54 	return -1;
55 }
56 
57 static uint32_t
find_buf_size(uint32_t input_size)58 find_buf_size(uint32_t input_size)
59 {
60 	uint32_t i;
61 
62 	/* From performance point of view the buffer size should be a
63 	 * power of 2 but also should be enough to store incompressible data
64 	 */
65 
66 	/* We're looking for nearest power of 2 buffer size, which is greater
67 	 * than input_size
68 	 */
69 	uint32_t size =
70 		!input_size ? MIN_COMPRESSED_BUF_SIZE : (input_size << 1);
71 
72 	for (i = UINT16_MAX + 1; !(i & size); i >>= 1)
73 		;
74 
75 	return i > ((UINT16_MAX + 1) >> 1)
76 			? (uint32_t)((float)input_size * EXPANSE_RATIO)
77 			: i;
78 }
79 
80 void
comp_perf_free_memory(struct comp_test_data * test_data,struct cperf_mem_resources * mem)81 comp_perf_free_memory(struct comp_test_data *test_data,
82 		      struct cperf_mem_resources *mem)
83 {
84 	uint32_t i;
85 
86 	if (mem->decomp_bufs != NULL)
87 		for (i = 0; i < mem->total_bufs; i++)
88 			rte_pktmbuf_free(mem->decomp_bufs[i]);
89 
90 	if (mem->comp_bufs != NULL)
91 		for (i = 0; i < mem->total_bufs; i++)
92 			rte_pktmbuf_free(mem->comp_bufs[i]);
93 
94 	rte_free(mem->decomp_bufs);
95 	rte_free(mem->comp_bufs);
96 	rte_free(mem->decompressed_data);
97 	rte_free(mem->compressed_data);
98 	rte_mempool_free(mem->op_pool);
99 	rte_mempool_free(mem->decomp_buf_pool);
100 	rte_mempool_free(mem->comp_buf_pool);
101 
102 	/* external mbuf support */
103 	if (mem->decomp_memzones != NULL) {
104 		for (i = 0; i < test_data->total_segs; i++)
105 			rte_memzone_free(mem->decomp_memzones[i]);
106 		rte_free(mem->decomp_memzones);
107 	}
108 	if (mem->comp_memzones != NULL) {
109 		for (i = 0; i < test_data->total_segs; i++)
110 			rte_memzone_free(mem->comp_memzones[i]);
111 		rte_free(mem->comp_memzones);
112 	}
113 	rte_free(mem->decomp_buf_infos);
114 	rte_free(mem->comp_buf_infos);
115 }
116 
117 static void
comp_perf_extbuf_free_cb(void * addr __rte_unused,void * opaque __rte_unused)118 comp_perf_extbuf_free_cb(void *addr __rte_unused, void *opaque __rte_unused)
119 {
120 }
121 
122 static const struct rte_memzone *
comp_perf_make_memzone(const char * name,struct cperf_mem_resources * mem,unsigned int number,size_t size)123 comp_perf_make_memzone(const char *name, struct cperf_mem_resources *mem,
124 		       unsigned int number, size_t size)
125 {
126 	unsigned int socket_id = rte_socket_id();
127 	char mz_name[RTE_MEMZONE_NAMESIZE];
128 	const struct rte_memzone *memzone;
129 
130 	snprintf(mz_name, RTE_MEMZONE_NAMESIZE, "%s_s%u_d%u_q%u_%d", name,
131 		 socket_id, mem->dev_id, mem->qp_id, number);
132 	memzone = rte_memzone_lookup(mz_name);
133 	if (memzone != NULL && memzone->len != size) {
134 		rte_memzone_free(memzone);
135 		memzone = NULL;
136 	}
137 	if (memzone == NULL) {
138 		memzone = rte_memzone_reserve_aligned(mz_name, size, socket_id,
139 				RTE_MEMZONE_IOVA_CONTIG, RTE_CACHE_LINE_SIZE);
140 		if (memzone == NULL)
141 			RTE_LOG(ERR, USER1, "Can't allocate memory zone %s\n",
142 				mz_name);
143 	}
144 	return memzone;
145 }
146 
147 static int
comp_perf_allocate_external_mbufs(struct comp_test_data * test_data,struct cperf_mem_resources * mem)148 comp_perf_allocate_external_mbufs(struct comp_test_data *test_data,
149 				  struct cperf_mem_resources *mem)
150 {
151 	uint32_t i;
152 
153 	mem->comp_memzones = rte_zmalloc_socket(NULL,
154 		test_data->total_segs * sizeof(struct rte_memzone *),
155 		0, rte_socket_id());
156 
157 	if (mem->comp_memzones == NULL) {
158 		RTE_LOG(ERR, USER1,
159 			"Memory to hold the compression memzones could not be allocated\n");
160 		return -1;
161 	}
162 
163 	mem->decomp_memzones = rte_zmalloc_socket(NULL,
164 		test_data->total_segs * sizeof(struct rte_memzone *),
165 		0, rte_socket_id());
166 
167 	if (mem->decomp_memzones == NULL) {
168 		RTE_LOG(ERR, USER1,
169 			"Memory to hold the decompression memzones could not be allocated\n");
170 		return -1;
171 	}
172 
173 	mem->comp_buf_infos = rte_zmalloc_socket(NULL,
174 		test_data->total_segs * sizeof(struct rte_mbuf_ext_shared_info),
175 		0, rte_socket_id());
176 
177 	if (mem->comp_buf_infos == NULL) {
178 		RTE_LOG(ERR, USER1,
179 			"Memory to hold the compression buf infos could not be allocated\n");
180 		return -1;
181 	}
182 
183 	mem->decomp_buf_infos = rte_zmalloc_socket(NULL,
184 		test_data->total_segs * sizeof(struct rte_mbuf_ext_shared_info),
185 		0, rte_socket_id());
186 
187 	if (mem->decomp_buf_infos == NULL) {
188 		RTE_LOG(ERR, USER1,
189 			"Memory to hold the decompression buf infos could not be allocated\n");
190 		return -1;
191 	}
192 
193 	for (i = 0; i < test_data->total_segs; i++) {
194 		mem->comp_memzones[i] = comp_perf_make_memzone("comp", mem,
195 				i, test_data->out_seg_sz);
196 		if (mem->comp_memzones[i] == NULL) {
197 			RTE_LOG(ERR, USER1,
198 				"Memory to hold the compression memzone could not be allocated\n");
199 			return -1;
200 		}
201 
202 		mem->decomp_memzones[i] = comp_perf_make_memzone("decomp", mem,
203 				i, test_data->seg_sz);
204 		if (mem->decomp_memzones[i] == NULL) {
205 			RTE_LOG(ERR, USER1,
206 				"Memory to hold the decompression memzone could not be allocated\n");
207 			return -1;
208 		}
209 
210 		mem->comp_buf_infos[i].free_cb =
211 				comp_perf_extbuf_free_cb;
212 		mem->comp_buf_infos[i].fcb_opaque = NULL;
213 		rte_mbuf_ext_refcnt_set(&mem->comp_buf_infos[i], 1);
214 
215 		mem->decomp_buf_infos[i].free_cb =
216 				comp_perf_extbuf_free_cb;
217 		mem->decomp_buf_infos[i].fcb_opaque = NULL;
218 		rte_mbuf_ext_refcnt_set(&mem->decomp_buf_infos[i], 1);
219 	}
220 
221 	return 0;
222 }
223 
224 int
comp_perf_allocate_memory(struct comp_test_data * test_data,struct cperf_mem_resources * mem)225 comp_perf_allocate_memory(struct comp_test_data *test_data,
226 			  struct cperf_mem_resources *mem)
227 {
228 	uint16_t comp_mbuf_size;
229 	uint16_t decomp_mbuf_size;
230 	size_t comp_data_size;
231 	size_t decomp_data_size;
232 	size_t output_data_sz;
233 
234 	test_data->out_seg_sz = find_buf_size(test_data->seg_sz);
235 
236 	if (test_data->test_op & COMPRESS) {
237 		/*
238 		 * Number of segments for input and output
239 		 * (compression and decompression)
240 		 */
241 		test_data->total_segs = DIV_CEIL(test_data->input_data_sz,
242 						 test_data->seg_sz);
243 	} else {
244 		/*
245 		 * When application does decompression only, input data is
246 		 * compressed and smaller than the output. The expected size of
247 		 * uncompressed data given by the user in segment size argument.
248 		 */
249 		test_data->total_segs = test_data->max_sgl_segs;
250 	}
251 
252 	output_data_sz = (size_t) test_data->out_seg_sz * test_data->total_segs;
253 	output_data_sz =
254 		RTE_MAX(output_data_sz, (size_t) MIN_COMPRESSED_BUF_SIZE);
255 
256 	if (test_data->use_external_mbufs != 0) {
257 		if (comp_perf_allocate_external_mbufs(test_data, mem) < 0)
258 			return -1;
259 		comp_mbuf_size = 0;
260 		decomp_mbuf_size = 0;
261 	} else if (test_data->test_op & COMPRESS) {
262 		comp_mbuf_size = test_data->out_seg_sz + RTE_PKTMBUF_HEADROOM;
263 		decomp_mbuf_size = test_data->seg_sz + RTE_PKTMBUF_HEADROOM;
264 	} else {
265 		comp_mbuf_size = test_data->seg_sz + RTE_PKTMBUF_HEADROOM;
266 		decomp_mbuf_size = test_data->out_seg_sz + RTE_PKTMBUF_HEADROOM;
267 	}
268 
269 	char pool_name[32] = "";
270 
271 	snprintf(pool_name, sizeof(pool_name), "comp_buf_pool_%u_qp_%u",
272 			mem->dev_id, mem->qp_id);
273 	mem->comp_buf_pool = rte_pktmbuf_pool_create(pool_name,
274 				test_data->total_segs,
275 				0, 0,
276 				comp_mbuf_size,
277 				rte_socket_id());
278 	if (mem->comp_buf_pool == NULL) {
279 		RTE_LOG(ERR, USER1, "Mbuf mempool could not be created\n");
280 		return -1;
281 	}
282 
283 	snprintf(pool_name, sizeof(pool_name), "decomp_buf_pool_%u_qp_%u",
284 			mem->dev_id, mem->qp_id);
285 	mem->decomp_buf_pool = rte_pktmbuf_pool_create(pool_name,
286 				test_data->total_segs,
287 				0, 0,
288 				decomp_mbuf_size,
289 				rte_socket_id());
290 	if (mem->decomp_buf_pool == NULL) {
291 		RTE_LOG(ERR, USER1, "Mbuf mempool could not be created\n");
292 		return -1;
293 	}
294 
295 	mem->total_bufs = DIV_CEIL(test_data->total_segs,
296 				   test_data->max_sgl_segs);
297 
298 	snprintf(pool_name, sizeof(pool_name), "op_pool_%u_qp_%u",
299 			mem->dev_id, mem->qp_id);
300 
301 	/* one mempool for both src and dst mbufs */
302 	mem->op_pool = rte_comp_op_pool_create(pool_name,
303 				mem->total_bufs * 2,
304 				0, 0, rte_socket_id());
305 	if (mem->op_pool == NULL) {
306 		RTE_LOG(ERR, USER1, "Comp op mempool could not be created\n");
307 		return -1;
308 	}
309 
310 	if (test_data->test_op & COMPRESS) {
311 		/*
312 		 * Compressed data might be a bit larger than input data,
313 		 * if data cannot be compressed
314 		 */
315 		comp_data_size = output_data_sz;
316 		decomp_data_size = test_data->input_data_sz;
317 	} else {
318 		comp_data_size = test_data->input_data_sz;
319 		decomp_data_size = output_data_sz;
320 	}
321 
322 	mem->compressed_data = rte_zmalloc_socket(NULL, comp_data_size, 0,
323 						  rte_socket_id());
324 	if (mem->compressed_data == NULL) {
325 		RTE_LOG(ERR, USER1, "Memory to hold the data from the input "
326 				"file could not be allocated\n");
327 		return -1;
328 	}
329 
330 	mem->decompressed_data = rte_zmalloc_socket(NULL, decomp_data_size, 0,
331 						    rte_socket_id());
332 	if (mem->decompressed_data == NULL) {
333 		RTE_LOG(ERR, USER1, "Memory to hold the data from the input "
334 				"file could not be allocated\n");
335 		return -1;
336 	}
337 
338 	mem->comp_bufs = rte_zmalloc_socket(NULL,
339 			mem->total_bufs * sizeof(struct rte_mbuf *),
340 			0, rte_socket_id());
341 	if (mem->comp_bufs == NULL) {
342 		RTE_LOG(ERR, USER1, "Memory to hold the compression mbufs"
343 				" could not be allocated\n");
344 		return -1;
345 	}
346 
347 	mem->decomp_bufs = rte_zmalloc_socket(NULL,
348 			mem->total_bufs * sizeof(struct rte_mbuf *),
349 			0, rte_socket_id());
350 	if (mem->decomp_bufs == NULL) {
351 		RTE_LOG(ERR, USER1, "Memory to hold the decompression mbufs"
352 				" could not be allocated\n");
353 		return -1;
354 	}
355 
356 	buffer_info.total_segments = test_data->total_segs;
357 	buffer_info.segment_sz = test_data->seg_sz;
358 	buffer_info.total_buffs = mem->total_bufs;
359 	buffer_info.segments_per_buff = test_data->max_sgl_segs;
360 	buffer_info.input_data_sz = test_data->input_data_sz;
361 
362 	return 0;
363 }
364 
365 int
prepare_bufs(struct comp_test_data * test_data,struct cperf_mem_resources * mem)366 prepare_bufs(struct comp_test_data *test_data, struct cperf_mem_resources *mem)
367 {
368 	uint32_t remaining_data = test_data->input_data_sz;
369 	uint32_t remaining_data_decomp = test_data->input_data_sz;
370 	uint8_t *input_data_ptr = test_data->input_data;
371 	size_t data_sz = 0;
372 	uint8_t *data_addr;
373 	uint32_t i, j;
374 	uint16_t segs_per_mbuf = 0;
375 	uint32_t cmz = 0;
376 	uint32_t dmz = 0;
377 	bool decompress_only = !!(test_data->test_op == DECOMPRESS);
378 
379 	for (i = 0; i < mem->total_bufs; i++) {
380 		/* Allocate data in input mbuf and copy data from input file */
381 		mem->decomp_bufs[i] =
382 			rte_pktmbuf_alloc(mem->decomp_buf_pool);
383 		if (mem->decomp_bufs[i] == NULL) {
384 			RTE_LOG(ERR, USER1, "Could not allocate mbuf\n");
385 			return -1;
386 		}
387 
388 		if (test_data->use_external_mbufs != 0) {
389 			rte_pktmbuf_attach_extbuf(mem->decomp_bufs[i],
390 					mem->decomp_memzones[dmz]->addr,
391 					mem->decomp_memzones[dmz]->iova,
392 					test_data->seg_sz,
393 					&mem->decomp_buf_infos[dmz]);
394 			dmz++;
395 		}
396 
397 		if (!decompress_only)
398 			data_sz = RTE_MIN(remaining_data, test_data->seg_sz);
399 		else
400 			data_sz = test_data->out_seg_sz;
401 
402 		data_addr = (uint8_t *) rte_pktmbuf_append(
403 					mem->decomp_bufs[i], data_sz);
404 		if (data_addr == NULL) {
405 			RTE_LOG(ERR, USER1, "Could not append data\n");
406 			return -1;
407 		}
408 
409 		if (!decompress_only) {
410 			rte_memcpy(data_addr, input_data_ptr, data_sz);
411 			input_data_ptr += data_sz;
412 			remaining_data -= data_sz;
413 		}
414 
415 		/* Already one segment in the mbuf */
416 		segs_per_mbuf = 1;
417 
418 		/* Chain mbufs if needed for input mbufs */
419 		while (segs_per_mbuf < test_data->max_sgl_segs
420 				&& remaining_data > 0) {
421 			struct rte_mbuf *next_seg =
422 				rte_pktmbuf_alloc(mem->decomp_buf_pool);
423 
424 			if (next_seg == NULL) {
425 				RTE_LOG(ERR, USER1,
426 					"Could not allocate mbuf\n");
427 				return -1;
428 			}
429 
430 			if (test_data->use_external_mbufs != 0) {
431 				rte_pktmbuf_attach_extbuf(
432 					next_seg,
433 					mem->decomp_memzones[dmz]->addr,
434 					mem->decomp_memzones[dmz]->iova,
435 					test_data->seg_sz,
436 					&mem->decomp_buf_infos[dmz]);
437 				dmz++;
438 			}
439 
440 			if (!decompress_only)
441 				data_sz = RTE_MIN(remaining_data,
442 						  test_data->seg_sz);
443 			else
444 				data_sz = test_data->out_seg_sz;
445 
446 			data_addr = (uint8_t *)rte_pktmbuf_append(next_seg,
447 				data_sz);
448 
449 			if (data_addr == NULL) {
450 				RTE_LOG(ERR, USER1, "Could not append data\n");
451 				return -1;
452 			}
453 
454 			if (!decompress_only) {
455 				rte_memcpy(data_addr, input_data_ptr, data_sz);
456 				input_data_ptr += data_sz;
457 				remaining_data -= data_sz;
458 			}
459 
460 			if (rte_pktmbuf_chain(mem->decomp_bufs[i],
461 					next_seg) < 0) {
462 				RTE_LOG(ERR, USER1, "Could not chain mbufs\n");
463 				return -1;
464 			}
465 			segs_per_mbuf++;
466 		}
467 
468 		/* Allocate data in output mbuf */
469 		mem->comp_bufs[i] =
470 			rte_pktmbuf_alloc(mem->comp_buf_pool);
471 		if (mem->comp_bufs[i] == NULL) {
472 			RTE_LOG(ERR, USER1, "Could not allocate mbuf\n");
473 			return -1;
474 		}
475 
476 		if (test_data->use_external_mbufs != 0) {
477 			rte_pktmbuf_attach_extbuf(mem->comp_bufs[i],
478 					mem->comp_memzones[cmz]->addr,
479 					mem->comp_memzones[cmz]->iova,
480 					test_data->out_seg_sz,
481 					&mem->comp_buf_infos[cmz]);
482 			cmz++;
483 		}
484 
485 		if (decompress_only)
486 			data_sz = RTE_MIN(remaining_data_decomp, test_data->seg_sz);
487 		else
488 			data_sz = test_data->out_seg_sz;
489 
490 		data_addr = (uint8_t *) rte_pktmbuf_append(mem->comp_bufs[i],
491 							   data_sz);
492 		if (data_addr == NULL) {
493 			RTE_LOG(ERR, USER1, "Could not append data\n");
494 			return -1;
495 		}
496 
497 		if (decompress_only) {
498 			rte_memcpy(data_addr, input_data_ptr, data_sz);
499 			input_data_ptr += data_sz;
500 			remaining_data_decomp -= data_sz;
501 		}
502 
503 		/* Chain mbufs if needed for output mbufs */
504 		for (j = 1; j < segs_per_mbuf && remaining_data_decomp > 0; j++) {
505 			struct rte_mbuf *next_seg =
506 				rte_pktmbuf_alloc(mem->comp_buf_pool);
507 
508 			if (next_seg == NULL) {
509 				RTE_LOG(ERR, USER1,
510 					"Could not allocate mbuf\n");
511 				return -1;
512 			}
513 
514 			if (test_data->use_external_mbufs != 0) {
515 				rte_pktmbuf_attach_extbuf(
516 					next_seg,
517 					mem->comp_memzones[cmz]->addr,
518 					mem->comp_memzones[cmz]->iova,
519 					test_data->out_seg_sz,
520 					&mem->comp_buf_infos[cmz]);
521 				cmz++;
522 			}
523 
524 			if (decompress_only)
525 				data_sz = RTE_MIN(remaining_data_decomp,
526 						  test_data->seg_sz);
527 			else
528 				data_sz = test_data->out_seg_sz;
529 
530 			data_addr = (uint8_t *)rte_pktmbuf_append(next_seg,
531 								  data_sz);
532 			if (data_addr == NULL) {
533 				RTE_LOG(ERR, USER1, "Could not append data\n");
534 				return -1;
535 			}
536 
537 			if (decompress_only) {
538 				rte_memcpy(data_addr, input_data_ptr, data_sz);
539 				input_data_ptr += data_sz;
540 				remaining_data_decomp -= data_sz;
541 			}
542 
543 			if (rte_pktmbuf_chain(mem->comp_bufs[i],
544 					next_seg) < 0) {
545 				RTE_LOG(ERR, USER1, "Could not chain mbufs\n");
546 				return -1;
547 			}
548 		}
549 	}
550 
551 	buffer_info.segments_per_last_buff = segs_per_mbuf;
552 	buffer_info.last_segment_sz = data_sz;
553 
554 	return 0;
555 }
556 
557 void
print_test_dynamics(const struct comp_test_data * test_data)558 print_test_dynamics(const struct comp_test_data *test_data)
559 {
560 	uint32_t opt_total_segs = DIV_CEIL(buffer_info.input_data_sz,
561 			MAX_SEG_SIZE);
562 
563 	if (buffer_info.total_buffs > 1) {
564 		if (test_data->test == CPERF_TEST_TYPE_THROUGHPUT) {
565 			printf("\nWarning: for the current input parameters, number"
566 				" of ops is higher than one, which may result"
567 				" in sub-optimal performance.\n");
568 			printf("To improve the performance (for the current"
569 				" input data) following parameters are"
570 				" suggested:\n");
571 			printf("	* Segment size: %d\n",
572 			       MAX_SEG_SIZE);
573 			printf("	* Number of segments: %u\n",
574 			       opt_total_segs);
575 		}
576 	} else if (buffer_info.total_buffs == 1) {
577 		printf("\nInfo: there is only one op with %u segments -"
578 				" the compression ratio is the best.\n",
579 			buffer_info.segments_per_last_buff);
580 		if (buffer_info.segment_sz < MAX_SEG_SIZE)
581 			printf("To reduce compression time, please use"
582 					" bigger segment size: %d.\n",
583 				MAX_SEG_SIZE);
584 		else if (buffer_info.segment_sz == MAX_SEG_SIZE)
585 			printf("Segment size is optimal for the best"
586 					" performance.\n");
587 	} else
588 		printf("Warning: something wrong happened!!\n");
589 
590 	printf("\nFor the current input parameters (segment size = %u,"
591 			" maximum segments per SGL = %u):\n",
592 		buffer_info.segment_sz,
593 		buffer_info.segments_per_buff);
594 	printf("	* Total number of buffers: %d\n",
595 		buffer_info.total_segments);
596 	printf("	* %u buffer(s) %u bytes long, last buffer %u"
597 			" byte(s) long\n",
598 		buffer_info.total_segments - 1,
599 		buffer_info.segment_sz,
600 		buffer_info.last_segment_sz);
601 	printf("	* Number of ops: %u\n", buffer_info.total_buffs);
602 	printf("	* Total memory allocation: %u\n",
603 		(buffer_info.total_segments - 1) * buffer_info.segment_sz
604 		+ buffer_info.last_segment_sz);
605 	if (buffer_info.total_buffs > 1)
606 		printf("	* %u ops: %u segment(s) in each,"
607 				" segment size %u\n",
608 			buffer_info.total_buffs - 1,
609 			buffer_info.segments_per_buff,
610 			buffer_info.segment_sz);
611 	if (buffer_info.segments_per_last_buff > 1) {
612 		printf("	* 1 op %u segments:\n",
613 				buffer_info.segments_per_last_buff);
614 		printf("		o %u segment size %u\n",
615 			buffer_info.segments_per_last_buff - 1,
616 			buffer_info.segment_sz);
617 		printf("		o last segment size %u\n",
618 			buffer_info.last_segment_sz);
619 	} else if (buffer_info.segments_per_last_buff == 1) {
620 		printf("	* 1 op (the last one): %u segment %u"
621 				" byte(s) long\n\n",
622 			buffer_info.segments_per_last_buff,
623 			buffer_info.last_segment_sz);
624 	}
625 	printf("\n");
626 }
627