xref: /openbmc/linux/drivers/ntb/test/ntb_perf.c (revision 74a22e8f)
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  *   redistributing this file, you may do so under either license.
4  *
5  *   GPL LICENSE SUMMARY
6  *
7  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
8  *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
9  *
10  *   This program is free software; you can redistribute it and/or modify
11  *   it under the terms of version 2 of the GNU General Public License as
12  *   published by the Free Software Foundation.
13  *
14  *   BSD LICENSE
15  *
16  *   Copyright(c) 2015 Intel Corporation. All rights reserved.
17  *   Copyright(c) 2017 T-Platforms. All Rights Reserved.
18  *
19  *   Redistribution and use in source and binary forms, with or without
20  *   modification, are permitted provided that the following conditions
21  *   are met:
22  *
23  *     * Redistributions of source code must retain the above copyright
24  *       notice, this list of conditions and the following disclaimer.
25  *     * Redistributions in binary form must reproduce the above copy
26  *       notice, this list of conditions and the following disclaimer in
27  *       the documentation and/or other materials provided with the
28  *       distribution.
29  *     * Neither the name of Intel Corporation nor the names of its
30  *       contributors may be used to endorse or promote products derived
31  *       from this software without specific prior written permission.
32  *
33  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
34  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
35  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
36  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
37  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
38  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
39  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
40  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
41  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
42  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
43  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
44  *
45  * PCIe NTB Perf Linux driver
46  */
47 
48 /*
49  * How to use this tool, by example.
50  *
51  * Assuming $DBG_DIR is something like:
52  * '/sys/kernel/debug/ntb_perf/0000:00:03.0'
53  * Suppose aside from local device there is at least one remote device
54  * connected to NTB with index 0.
55  *-----------------------------------------------------------------------------
56  * Eg: install driver with specified chunk/total orders and dma-enabled flag
57  *
58  * root@self# insmod ntb_perf.ko chunk_order=19 total_order=28 use_dma
59  *-----------------------------------------------------------------------------
60  * Eg: check NTB ports (index) and MW mapping information
61  *
62  * root@self# cat $DBG_DIR/info
63  *-----------------------------------------------------------------------------
64  * Eg: start performance test with peer (index 0) and get the test metrics
65  *
66  * root@self# echo 0 > $DBG_DIR/run
67  * root@self# cat $DBG_DIR/run
68  */
69 
70 #include <linux/init.h>
71 #include <linux/kernel.h>
72 #include <linux/module.h>
73 #include <linux/sched.h>
74 #include <linux/wait.h>
75 #include <linux/dma-mapping.h>
76 #include <linux/dmaengine.h>
77 #include <linux/pci.h>
78 #include <linux/ktime.h>
79 #include <linux/slab.h>
80 #include <linux/delay.h>
81 #include <linux/sizes.h>
82 #include <linux/workqueue.h>
83 #include <linux/debugfs.h>
84 #include <linux/random.h>
85 #include <linux/ntb.h>
86 
87 #define DRIVER_NAME		"ntb_perf"
88 #define DRIVER_VERSION		"2.0"
89 
90 MODULE_LICENSE("Dual BSD/GPL");
91 MODULE_VERSION(DRIVER_VERSION);
92 MODULE_AUTHOR("Dave Jiang <dave.jiang@intel.com>");
93 MODULE_DESCRIPTION("PCIe NTB Performance Measurement Tool");
94 
95 #define MAX_THREADS_CNT		32
96 #define DEF_THREADS_CNT		1
97 #define MAX_CHUNK_SIZE		SZ_1M
98 #define MAX_CHUNK_ORDER		20 /* no larger than 1M */
99 
100 #define DMA_TRIES		100
101 #define DMA_MDELAY		10
102 
103 #define MSG_TRIES		500
104 #define MSG_UDELAY_LOW		1000
105 #define MSG_UDELAY_HIGH		2000
106 
107 #define PERF_BUF_LEN 1024
108 
109 static unsigned long max_mw_size;
110 module_param(max_mw_size, ulong, 0644);
111 MODULE_PARM_DESC(max_mw_size, "Upper limit of memory window size");
112 
113 static unsigned char chunk_order = 19; /* 512K */
114 module_param(chunk_order, byte, 0644);
115 MODULE_PARM_DESC(chunk_order, "Data chunk order [2^n] to transfer");
116 
117 static unsigned char total_order = 30; /* 1G */
118 module_param(total_order, byte, 0644);
119 MODULE_PARM_DESC(total_order, "Total data order [2^n] to transfer");
120 
121 static bool use_dma; /* default to 0 */
122 module_param(use_dma, bool, 0644);
123 MODULE_PARM_DESC(use_dma, "Use DMA engine to measure performance");
124 
125 /*==============================================================================
126  *                         Perf driver data definition
127  *==============================================================================
128  */
129 
130 enum perf_cmd {
131 	PERF_CMD_INVAL = -1,/* invalid spad command */
132 	PERF_CMD_SSIZE = 0, /* send out buffer size */
133 	PERF_CMD_RSIZE = 1, /* recv in  buffer size */
134 	PERF_CMD_SXLAT = 2, /* send in  buffer xlat */
135 	PERF_CMD_RXLAT = 3, /* recv out buffer xlat */
136 	PERF_CMD_CLEAR = 4, /* clear allocated memory */
137 	PERF_STS_DONE  = 5, /* init is done */
138 	PERF_STS_LNKUP = 6, /* link up state flag */
139 };
140 
141 struct perf_ctx;
142 
143 struct perf_peer {
144 	struct perf_ctx	*perf;
145 	int pidx;
146 	int gidx;
147 
148 	/* Outbound MW params */
149 	u64 outbuf_xlat;
150 	resource_size_t outbuf_size;
151 	void __iomem *outbuf;
152 
153 	/* Inbound MW params */
154 	dma_addr_t inbuf_xlat;
155 	resource_size_t inbuf_size;
156 	void		*inbuf;
157 
158 	/* NTB connection setup service */
159 	struct work_struct	service;
160 	unsigned long		sts;
161 };
162 #define to_peer_service(__work) \
163 	container_of(__work, struct perf_peer, service)
164 
165 struct perf_thread {
166 	struct perf_ctx *perf;
167 	int tidx;
168 
169 	/* DMA-based test sync parameters */
170 	atomic_t dma_sync;
171 	wait_queue_head_t dma_wait;
172 	struct dma_chan *dma_chan;
173 
174 	/* Data source and measured statistics */
175 	void *src;
176 	u64 copied;
177 	ktime_t duration;
178 	int status;
179 	struct work_struct work;
180 };
181 #define to_thread_work(__work) \
182 	container_of(__work, struct perf_thread, work)
183 
184 struct perf_ctx {
185 	struct ntb_dev *ntb;
186 
187 	/* Global device index and peers descriptors */
188 	int gidx;
189 	int pcnt;
190 	struct perf_peer *peers;
191 
192 	/* Performance measuring work-threads interface */
193 	unsigned long busy_flag;
194 	wait_queue_head_t twait;
195 	atomic_t tsync;
196 	u8 tcnt;
197 	struct perf_peer *test_peer;
198 	struct perf_thread threads[MAX_THREADS_CNT];
199 
200 	/* Scratchpad/Message IO operations */
201 	int (*cmd_send)(struct perf_peer *peer, enum perf_cmd cmd, u64 data);
202 	int (*cmd_recv)(struct perf_ctx *perf, int *pidx, enum perf_cmd *cmd,
203 			u64 *data);
204 
205 	struct dentry *dbgfs_dir;
206 };
207 
208 /*
209  * Scratchpads-base commands interface
210  */
211 #define PERF_SPAD_CNT(_pcnt) \
212 	(3*((_pcnt) + 1))
213 #define PERF_SPAD_CMD(_gidx) \
214 	(3*(_gidx))
215 #define PERF_SPAD_LDATA(_gidx) \
216 	(3*(_gidx) + 1)
217 #define PERF_SPAD_HDATA(_gidx) \
218 	(3*(_gidx) + 2)
219 #define PERF_SPAD_NOTIFY(_gidx) \
220 	(BIT_ULL(_gidx))
221 
222 /*
223  * Messages-base commands interface
224  */
225 #define PERF_MSG_CNT		3
226 #define PERF_MSG_CMD		0
227 #define PERF_MSG_LDATA		1
228 #define PERF_MSG_HDATA		2
229 
230 /*==============================================================================
231  *                           Static data declarations
232  *==============================================================================
233  */
234 
235 static struct dentry *perf_dbgfs_topdir;
236 
237 static struct workqueue_struct *perf_wq __read_mostly;
238 
239 /*==============================================================================
240  *                  NTB cross-link commands execution service
241  *==============================================================================
242  */
243 
244 static void perf_terminate_test(struct perf_ctx *perf);
245 
246 static inline bool perf_link_is_up(struct perf_peer *peer)
247 {
248 	u64 link;
249 
250 	link = ntb_link_is_up(peer->perf->ntb, NULL, NULL);
251 	return !!(link & BIT_ULL_MASK(peer->pidx));
252 }
253 
254 static int perf_spad_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
255 			      u64 data)
256 {
257 	struct perf_ctx *perf = peer->perf;
258 	int try;
259 	u32 sts;
260 
261 	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
262 
263 	/*
264 	 * Perform predefined number of attempts before give up.
265 	 * We are sending the data to the port specific scratchpad, so
266 	 * to prevent a multi-port access race-condition. Additionally
267 	 * there is no need in local locking since only thread-safe
268 	 * service work is using this method.
269 	 */
270 	for (try = 0; try < MSG_TRIES; try++) {
271 		if (!perf_link_is_up(peer))
272 			return -ENOLINK;
273 
274 		sts = ntb_peer_spad_read(perf->ntb, peer->pidx,
275 					 PERF_SPAD_CMD(perf->gidx));
276 		if (sts != PERF_CMD_INVAL) {
277 			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
278 			continue;
279 		}
280 
281 		ntb_peer_spad_write(perf->ntb, peer->pidx,
282 				    PERF_SPAD_LDATA(perf->gidx),
283 				    lower_32_bits(data));
284 		ntb_peer_spad_write(perf->ntb, peer->pidx,
285 				    PERF_SPAD_HDATA(perf->gidx),
286 				    upper_32_bits(data));
287 		ntb_peer_spad_write(perf->ntb, peer->pidx,
288 				    PERF_SPAD_CMD(perf->gidx),
289 				    cmd);
290 		ntb_peer_db_set(perf->ntb, PERF_SPAD_NOTIFY(peer->gidx));
291 
292 		dev_dbg(&perf->ntb->dev, "DB ring peer %#llx\n",
293 			PERF_SPAD_NOTIFY(peer->gidx));
294 
295 		break;
296 	}
297 
298 	return try < MSG_TRIES ? 0 : -EAGAIN;
299 }
300 
301 static int perf_spad_cmd_recv(struct perf_ctx *perf, int *pidx,
302 			      enum perf_cmd *cmd, u64 *data)
303 {
304 	struct perf_peer *peer;
305 	u32 val;
306 
307 	ntb_db_clear(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
308 
309 	/*
310 	 * We start scanning all over, since cleared DB may have been set
311 	 * by any peer. Yes, it makes peer with smaller index being
312 	 * serviced with greater priority, but it's convenient for spad
313 	 * and message code unification and simplicity.
314 	 */
315 	for (*pidx = 0; *pidx < perf->pcnt; (*pidx)++) {
316 		peer = &perf->peers[*pidx];
317 
318 		if (!perf_link_is_up(peer))
319 			continue;
320 
321 		val = ntb_spad_read(perf->ntb, PERF_SPAD_CMD(peer->gidx));
322 		if (val == PERF_CMD_INVAL)
323 			continue;
324 
325 		*cmd = val;
326 
327 		val = ntb_spad_read(perf->ntb, PERF_SPAD_LDATA(peer->gidx));
328 		*data = val;
329 
330 		val = ntb_spad_read(perf->ntb, PERF_SPAD_HDATA(peer->gidx));
331 		*data |= (u64)val << 32;
332 
333 		/* Next command can be retrieved from now */
334 		ntb_spad_write(perf->ntb, PERF_SPAD_CMD(peer->gidx),
335 			       PERF_CMD_INVAL);
336 
337 		dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
338 
339 		return 0;
340 	}
341 
342 	return -ENODATA;
343 }
344 
345 static int perf_msg_cmd_send(struct perf_peer *peer, enum perf_cmd cmd,
346 			     u64 data)
347 {
348 	struct perf_ctx *perf = peer->perf;
349 	int try, ret;
350 	u64 outbits;
351 
352 	dev_dbg(&perf->ntb->dev, "CMD send: %d 0x%llx\n", cmd, data);
353 
354 	/*
355 	 * Perform predefined number of attempts before give up. Message
356 	 * registers are free of race-condition problem when accessed
357 	 * from different ports, so we don't need splitting registers
358 	 * by global device index. We also won't have local locking,
359 	 * since the method is used from service work only.
360 	 */
361 	outbits = ntb_msg_outbits(perf->ntb);
362 	for (try = 0; try < MSG_TRIES; try++) {
363 		if (!perf_link_is_up(peer))
364 			return -ENOLINK;
365 
366 		ret = ntb_msg_clear_sts(perf->ntb, outbits);
367 		if (ret)
368 			return ret;
369 
370 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_LDATA,
371 				   lower_32_bits(data));
372 
373 		if (ntb_msg_read_sts(perf->ntb) & outbits) {
374 			usleep_range(MSG_UDELAY_LOW, MSG_UDELAY_HIGH);
375 			continue;
376 		}
377 
378 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_HDATA,
379 				   upper_32_bits(data));
380 
381 		/* This call shall trigger peer message event */
382 		ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_CMD, cmd);
383 
384 		break;
385 	}
386 
387 	return try < MSG_TRIES ? 0 : -EAGAIN;
388 }
389 
390 static int perf_msg_cmd_recv(struct perf_ctx *perf, int *pidx,
391 			     enum perf_cmd *cmd, u64 *data)
392 {
393 	u64 inbits;
394 	u32 val;
395 
396 	inbits = ntb_msg_inbits(perf->ntb);
397 
398 	if (hweight64(ntb_msg_read_sts(perf->ntb) & inbits) < 3)
399 		return -ENODATA;
400 
401 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_CMD);
402 	*cmd = val;
403 
404 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_LDATA);
405 	*data = val;
406 
407 	val = ntb_msg_read(perf->ntb, pidx, PERF_MSG_HDATA);
408 	*data |= (u64)val << 32;
409 
410 	/* Next command can be retrieved from now */
411 	ntb_msg_clear_sts(perf->ntb, inbits);
412 
413 	dev_dbg(&perf->ntb->dev, "CMD recv: %d 0x%llx\n", *cmd, *data);
414 
415 	return 0;
416 }
417 
418 static int perf_cmd_send(struct perf_peer *peer, enum perf_cmd cmd, u64 data)
419 {
420 	struct perf_ctx *perf = peer->perf;
421 
422 	if (cmd == PERF_CMD_SSIZE || cmd == PERF_CMD_SXLAT)
423 		return perf->cmd_send(peer, cmd, data);
424 
425 	dev_err(&perf->ntb->dev, "Send invalid command\n");
426 	return -EINVAL;
427 }
428 
429 static int perf_cmd_exec(struct perf_peer *peer, enum perf_cmd cmd)
430 {
431 	switch (cmd) {
432 	case PERF_CMD_SSIZE:
433 	case PERF_CMD_RSIZE:
434 	case PERF_CMD_SXLAT:
435 	case PERF_CMD_RXLAT:
436 	case PERF_CMD_CLEAR:
437 		break;
438 	default:
439 		dev_err(&peer->perf->ntb->dev, "Exec invalid command\n");
440 		return -EINVAL;
441 	}
442 
443 	/* No need of memory barrier, since bit ops have invernal lock */
444 	set_bit(cmd, &peer->sts);
445 
446 	dev_dbg(&peer->perf->ntb->dev, "CMD exec: %d\n", cmd);
447 
448 	(void)queue_work(system_highpri_wq, &peer->service);
449 
450 	return 0;
451 }
452 
453 static int perf_cmd_recv(struct perf_ctx *perf)
454 {
455 	struct perf_peer *peer;
456 	int ret, pidx, cmd;
457 	u64 data;
458 
459 	while (!(ret = perf->cmd_recv(perf, &pidx, &cmd, &data))) {
460 		peer = &perf->peers[pidx];
461 
462 		switch (cmd) {
463 		case PERF_CMD_SSIZE:
464 			peer->inbuf_size = data;
465 			return perf_cmd_exec(peer, PERF_CMD_RSIZE);
466 		case PERF_CMD_SXLAT:
467 			peer->outbuf_xlat = data;
468 			return perf_cmd_exec(peer, PERF_CMD_RXLAT);
469 		default:
470 			dev_err(&perf->ntb->dev, "Recv invalid command\n");
471 			return -EINVAL;
472 		}
473 	}
474 
475 	/* Return 0 if no data left to process, otherwise an error */
476 	return ret == -ENODATA ? 0 : ret;
477 }
478 
479 static void perf_link_event(void *ctx)
480 {
481 	struct perf_ctx *perf = ctx;
482 	struct perf_peer *peer;
483 	bool lnk_up;
484 	int pidx;
485 
486 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
487 		peer = &perf->peers[pidx];
488 
489 		lnk_up = perf_link_is_up(peer);
490 
491 		if (lnk_up &&
492 		    !test_and_set_bit(PERF_STS_LNKUP, &peer->sts)) {
493 			perf_cmd_exec(peer, PERF_CMD_SSIZE);
494 		} else if (!lnk_up &&
495 			   test_and_clear_bit(PERF_STS_LNKUP, &peer->sts)) {
496 			perf_cmd_exec(peer, PERF_CMD_CLEAR);
497 		}
498 	}
499 }
500 
501 static void perf_db_event(void *ctx, int vec)
502 {
503 	struct perf_ctx *perf = ctx;
504 
505 	dev_dbg(&perf->ntb->dev, "DB vec %d mask %#llx bits %#llx\n", vec,
506 		ntb_db_vector_mask(perf->ntb, vec), ntb_db_read(perf->ntb));
507 
508 	/* Just receive all available commands */
509 	(void)perf_cmd_recv(perf);
510 }
511 
512 static void perf_msg_event(void *ctx)
513 {
514 	struct perf_ctx *perf = ctx;
515 
516 	dev_dbg(&perf->ntb->dev, "Msg status bits %#llx\n",
517 		ntb_msg_read_sts(perf->ntb));
518 
519 	/* Messages are only sent one-by-one */
520 	(void)perf_cmd_recv(perf);
521 }
522 
523 static const struct ntb_ctx_ops perf_ops = {
524 	.link_event = perf_link_event,
525 	.db_event = perf_db_event,
526 	.msg_event = perf_msg_event
527 };
528 
529 static void perf_free_outbuf(struct perf_peer *peer)
530 {
531 	(void)ntb_peer_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
532 }
533 
534 static int perf_setup_outbuf(struct perf_peer *peer)
535 {
536 	struct perf_ctx *perf = peer->perf;
537 	int ret;
538 
539 	/* Outbuf size can be unaligned due to custom max_mw_size */
540 	ret = ntb_peer_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
541 				    peer->outbuf_xlat, peer->outbuf_size);
542 	if (ret) {
543 		dev_err(&perf->ntb->dev, "Failed to set outbuf translation\n");
544 		return ret;
545 	}
546 
547 	/* Initialization is finally done */
548 	set_bit(PERF_STS_DONE, &peer->sts);
549 
550 	return 0;
551 }
552 
553 static void perf_free_inbuf(struct perf_peer *peer)
554 {
555 	if (!peer->inbuf)
556 		return;
557 
558 	(void)ntb_mw_clear_trans(peer->perf->ntb, peer->pidx, peer->gidx);
559 	dma_free_coherent(&peer->perf->ntb->dev, peer->inbuf_size,
560 			  peer->inbuf, peer->inbuf_xlat);
561 	peer->inbuf = NULL;
562 }
563 
564 static int perf_setup_inbuf(struct perf_peer *peer)
565 {
566 	resource_size_t xlat_align, size_align, size_max;
567 	struct perf_ctx *perf = peer->perf;
568 	int ret;
569 
570 	/* Get inbound MW parameters */
571 	ret = ntb_mw_get_align(perf->ntb, peer->pidx, perf->gidx,
572 			       &xlat_align, &size_align, &size_max);
573 	if (ret) {
574 		dev_err(&perf->ntb->dev, "Couldn't get inbuf restrictions\n");
575 		return ret;
576 	}
577 
578 	if (peer->inbuf_size > size_max) {
579 		dev_err(&perf->ntb->dev, "Too big inbuf size %pa > %pa\n",
580 			&peer->inbuf_size, &size_max);
581 		return -EINVAL;
582 	}
583 
584 	peer->inbuf_size = round_up(peer->inbuf_size, size_align);
585 
586 	perf_free_inbuf(peer);
587 
588 	peer->inbuf = dma_alloc_coherent(&perf->ntb->dev, peer->inbuf_size,
589 					 &peer->inbuf_xlat, GFP_KERNEL);
590 	if (!peer->inbuf) {
591 		dev_err(&perf->ntb->dev, "Failed to alloc inbuf of %pa\n",
592 			&peer->inbuf_size);
593 		return -ENOMEM;
594 	}
595 	if (!IS_ALIGNED(peer->inbuf_xlat, xlat_align)) {
596 		dev_err(&perf->ntb->dev, "Unaligned inbuf allocated\n");
597 		goto err_free_inbuf;
598 	}
599 
600 	ret = ntb_mw_set_trans(perf->ntb, peer->pidx, peer->gidx,
601 			       peer->inbuf_xlat, peer->inbuf_size);
602 	if (ret) {
603 		dev_err(&perf->ntb->dev, "Failed to set inbuf translation\n");
604 		goto err_free_inbuf;
605 	}
606 
607 	/*
608 	 * We submit inbuf xlat transmission cmd for execution here to follow
609 	 * the code architecture, even though this method is called from service
610 	 * work itself so the command will be executed right after it returns.
611 	 */
612 	(void)perf_cmd_exec(peer, PERF_CMD_SXLAT);
613 
614 	return 0;
615 
616 err_free_inbuf:
617 	perf_free_inbuf(peer);
618 
619 	return ret;
620 }
621 
622 static void perf_service_work(struct work_struct *work)
623 {
624 	struct perf_peer *peer = to_peer_service(work);
625 
626 	if (test_and_clear_bit(PERF_CMD_SSIZE, &peer->sts))
627 		perf_cmd_send(peer, PERF_CMD_SSIZE, peer->outbuf_size);
628 
629 	if (test_and_clear_bit(PERF_CMD_RSIZE, &peer->sts))
630 		perf_setup_inbuf(peer);
631 
632 	if (test_and_clear_bit(PERF_CMD_SXLAT, &peer->sts))
633 		perf_cmd_send(peer, PERF_CMD_SXLAT, peer->inbuf_xlat);
634 
635 	if (test_and_clear_bit(PERF_CMD_RXLAT, &peer->sts))
636 		perf_setup_outbuf(peer);
637 
638 	if (test_and_clear_bit(PERF_CMD_CLEAR, &peer->sts)) {
639 		clear_bit(PERF_STS_DONE, &peer->sts);
640 		if (test_bit(0, &peer->perf->busy_flag) &&
641 		    peer == peer->perf->test_peer) {
642 			dev_warn(&peer->perf->ntb->dev,
643 				"Freeing while test on-fly\n");
644 			perf_terminate_test(peer->perf);
645 		}
646 		perf_free_outbuf(peer);
647 		perf_free_inbuf(peer);
648 	}
649 }
650 
651 static int perf_init_service(struct perf_ctx *perf)
652 {
653 	u64 mask;
654 
655 	if (ntb_peer_mw_count(perf->ntb) < perf->pcnt + 1) {
656 		dev_err(&perf->ntb->dev, "Not enough memory windows\n");
657 		return -EINVAL;
658 	}
659 
660 	if (ntb_msg_count(perf->ntb) >= PERF_MSG_CNT) {
661 		perf->cmd_send = perf_msg_cmd_send;
662 		perf->cmd_recv = perf_msg_cmd_recv;
663 
664 		dev_dbg(&perf->ntb->dev, "Message service initialized\n");
665 
666 		return 0;
667 	}
668 
669 	dev_dbg(&perf->ntb->dev, "Message service unsupported\n");
670 
671 	mask = GENMASK_ULL(perf->pcnt, 0);
672 	if (ntb_spad_count(perf->ntb) >= PERF_SPAD_CNT(perf->pcnt) &&
673 	    (ntb_db_valid_mask(perf->ntb) & mask) == mask) {
674 		perf->cmd_send = perf_spad_cmd_send;
675 		perf->cmd_recv = perf_spad_cmd_recv;
676 
677 		dev_dbg(&perf->ntb->dev, "Scratchpad service initialized\n");
678 
679 		return 0;
680 	}
681 
682 	dev_dbg(&perf->ntb->dev, "Scratchpad service unsupported\n");
683 
684 	dev_err(&perf->ntb->dev, "Command services unsupported\n");
685 
686 	return -EINVAL;
687 }
688 
689 static int perf_enable_service(struct perf_ctx *perf)
690 {
691 	u64 mask, incmd_bit;
692 	int ret, sidx, scnt;
693 
694 	mask = ntb_db_valid_mask(perf->ntb);
695 	(void)ntb_db_set_mask(perf->ntb, mask);
696 
697 	ret = ntb_set_ctx(perf->ntb, perf, &perf_ops);
698 	if (ret)
699 		return ret;
700 
701 	if (perf->cmd_send == perf_msg_cmd_send) {
702 		u64 inbits, outbits;
703 
704 		inbits = ntb_msg_inbits(perf->ntb);
705 		outbits = ntb_msg_outbits(perf->ntb);
706 		(void)ntb_msg_set_mask(perf->ntb, inbits | outbits);
707 
708 		incmd_bit = BIT_ULL(__ffs64(inbits));
709 		ret = ntb_msg_clear_mask(perf->ntb, incmd_bit);
710 
711 		dev_dbg(&perf->ntb->dev, "MSG sts unmasked %#llx\n", incmd_bit);
712 	} else {
713 		scnt = ntb_spad_count(perf->ntb);
714 		for (sidx = 0; sidx < scnt; sidx++)
715 			ntb_spad_write(perf->ntb, sidx, PERF_CMD_INVAL);
716 		incmd_bit = PERF_SPAD_NOTIFY(perf->gidx);
717 		ret = ntb_db_clear_mask(perf->ntb, incmd_bit);
718 
719 		dev_dbg(&perf->ntb->dev, "DB bits unmasked %#llx\n", incmd_bit);
720 	}
721 	if (ret) {
722 		ntb_clear_ctx(perf->ntb);
723 		return ret;
724 	}
725 
726 	ntb_link_enable(perf->ntb, NTB_SPEED_AUTO, NTB_WIDTH_AUTO);
727 	/* Might be not necessary */
728 	ntb_link_event(perf->ntb);
729 
730 	return 0;
731 }
732 
733 static void perf_disable_service(struct perf_ctx *perf)
734 {
735 	int pidx;
736 
737 	ntb_link_disable(perf->ntb);
738 
739 	if (perf->cmd_send == perf_msg_cmd_send) {
740 		u64 inbits;
741 
742 		inbits = ntb_msg_inbits(perf->ntb);
743 		(void)ntb_msg_set_mask(perf->ntb, inbits);
744 	} else {
745 		(void)ntb_db_set_mask(perf->ntb, PERF_SPAD_NOTIFY(perf->gidx));
746 	}
747 
748 	ntb_clear_ctx(perf->ntb);
749 
750 	for (pidx = 0; pidx < perf->pcnt; pidx++)
751 		perf_cmd_exec(&perf->peers[pidx], PERF_CMD_CLEAR);
752 
753 	for (pidx = 0; pidx < perf->pcnt; pidx++)
754 		flush_work(&perf->peers[pidx].service);
755 }
756 
757 /*==============================================================================
758  *                      Performance measuring work-thread
759  *==============================================================================
760  */
761 
762 static void perf_dma_copy_callback(void *data)
763 {
764 	struct perf_thread *pthr = data;
765 
766 	atomic_dec(&pthr->dma_sync);
767 	wake_up(&pthr->dma_wait);
768 }
769 
770 static int perf_copy_chunk(struct perf_thread *pthr,
771 			   void __iomem *dst, void *src, size_t len)
772 {
773 	struct dma_async_tx_descriptor *tx;
774 	struct dmaengine_unmap_data *unmap;
775 	struct device *dma_dev;
776 	int try = 0, ret = 0;
777 
778 	if (!use_dma) {
779 		memcpy_toio(dst, src, len);
780 		goto ret_check_tsync;
781 	}
782 
783 	dma_dev = pthr->dma_chan->device->dev;
784 
785 	if (!is_dma_copy_aligned(pthr->dma_chan->device, offset_in_page(src),
786 				 offset_in_page(dst), len))
787 		return -EIO;
788 
789 	unmap = dmaengine_get_unmap_data(dma_dev, 2, GFP_NOWAIT);
790 	if (!unmap)
791 		return -ENOMEM;
792 
793 	unmap->len = len;
794 	unmap->addr[0] = dma_map_page(dma_dev, virt_to_page(src),
795 		offset_in_page(src), len, DMA_TO_DEVICE);
796 	if (dma_mapping_error(dma_dev, unmap->addr[0])) {
797 		ret = -EIO;
798 		goto err_free_resource;
799 	}
800 	unmap->to_cnt = 1;
801 
802 	unmap->addr[1] = dma_map_page(dma_dev, virt_to_page(dst),
803 		offset_in_page(dst), len, DMA_FROM_DEVICE);
804 	if (dma_mapping_error(dma_dev, unmap->addr[1])) {
805 		ret = -EIO;
806 		goto err_free_resource;
807 	}
808 	unmap->from_cnt = 1;
809 
810 	do {
811 		tx = dmaengine_prep_dma_memcpy(pthr->dma_chan, unmap->addr[1],
812 			unmap->addr[0], len, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
813 		if (!tx)
814 			msleep(DMA_MDELAY);
815 	} while (!tx && (try++ < DMA_TRIES));
816 
817 	if (!tx) {
818 		ret = -EIO;
819 		goto err_free_resource;
820 	}
821 
822 	tx->callback = perf_dma_copy_callback;
823 	tx->callback_param = pthr;
824 	dma_set_unmap(tx, unmap);
825 
826 	ret = dma_submit_error(dmaengine_submit(tx));
827 	if (ret) {
828 		dmaengine_unmap_put(unmap);
829 		goto err_free_resource;
830 	}
831 
832 	dmaengine_unmap_put(unmap);
833 
834 	atomic_inc(&pthr->dma_sync);
835 	dma_async_issue_pending(pthr->dma_chan);
836 
837 ret_check_tsync:
838 	return likely(atomic_read(&pthr->perf->tsync) > 0) ? 0 : -EINTR;
839 
840 err_free_resource:
841 	dmaengine_unmap_put(unmap);
842 
843 	return ret;
844 }
845 
846 static bool perf_dma_filter(struct dma_chan *chan, void *data)
847 {
848 	struct perf_ctx *perf = data;
849 	int node;
850 
851 	node = dev_to_node(&perf->ntb->dev);
852 
853 	return node == NUMA_NO_NODE || node == dev_to_node(chan->device->dev);
854 }
855 
856 static int perf_init_test(struct perf_thread *pthr)
857 {
858 	struct perf_ctx *perf = pthr->perf;
859 	dma_cap_mask_t dma_mask;
860 
861 	pthr->src = kmalloc_node(perf->test_peer->outbuf_size, GFP_KERNEL,
862 				 dev_to_node(&perf->ntb->dev));
863 	if (!pthr->src)
864 		return -ENOMEM;
865 
866 	get_random_bytes(pthr->src, perf->test_peer->outbuf_size);
867 
868 	if (!use_dma)
869 		return 0;
870 
871 	dma_cap_zero(dma_mask);
872 	dma_cap_set(DMA_MEMCPY, dma_mask);
873 	pthr->dma_chan = dma_request_channel(dma_mask, perf_dma_filter, perf);
874 	if (!pthr->dma_chan) {
875 		dev_err(&perf->ntb->dev, "%d: Failed to get DMA channel\n",
876 			pthr->tidx);
877 		atomic_dec(&perf->tsync);
878 		wake_up(&perf->twait);
879 		kfree(pthr->src);
880 		return -ENODEV;
881 	}
882 
883 	atomic_set(&pthr->dma_sync, 0);
884 
885 	return 0;
886 }
887 
888 static int perf_run_test(struct perf_thread *pthr)
889 {
890 	struct perf_peer *peer = pthr->perf->test_peer;
891 	struct perf_ctx *perf = pthr->perf;
892 	void __iomem *flt_dst, *bnd_dst;
893 	u64 total_size, chunk_size;
894 	void *flt_src;
895 	int ret = 0;
896 
897 	total_size = 1ULL << total_order;
898 	chunk_size = 1ULL << chunk_order;
899 	chunk_size = min_t(u64, peer->outbuf_size, chunk_size);
900 
901 	flt_src = pthr->src;
902 	bnd_dst = peer->outbuf + peer->outbuf_size;
903 	flt_dst = peer->outbuf;
904 
905 	pthr->duration = ktime_get();
906 
907 	/* Copied field is cleared on test launch stage */
908 	while (pthr->copied < total_size) {
909 		ret = perf_copy_chunk(pthr, flt_dst, flt_src, chunk_size);
910 		if (ret) {
911 			dev_err(&perf->ntb->dev, "%d: Got error %d on test\n",
912 				pthr->tidx, ret);
913 			return ret;
914 		}
915 
916 		pthr->copied += chunk_size;
917 
918 		flt_dst += chunk_size;
919 		flt_src += chunk_size;
920 		if (flt_dst >= bnd_dst || flt_dst < peer->outbuf) {
921 			flt_dst = peer->outbuf;
922 			flt_src = pthr->src;
923 		}
924 
925 		/* Give up CPU to give a chance for other threads to use it */
926 		schedule();
927 	}
928 
929 	return 0;
930 }
931 
932 static int perf_sync_test(struct perf_thread *pthr)
933 {
934 	struct perf_ctx *perf = pthr->perf;
935 
936 	if (!use_dma)
937 		goto no_dma_ret;
938 
939 	wait_event(pthr->dma_wait,
940 		   (atomic_read(&pthr->dma_sync) == 0 ||
941 		    atomic_read(&perf->tsync) < 0));
942 
943 	if (atomic_read(&perf->tsync) < 0)
944 		return -EINTR;
945 
946 no_dma_ret:
947 	pthr->duration = ktime_sub(ktime_get(), pthr->duration);
948 
949 	dev_dbg(&perf->ntb->dev, "%d: copied %llu bytes\n",
950 		pthr->tidx, pthr->copied);
951 
952 	dev_dbg(&perf->ntb->dev, "%d: lasted %llu usecs\n",
953 		pthr->tidx, ktime_to_us(pthr->duration));
954 
955 	dev_dbg(&perf->ntb->dev, "%d: %llu MBytes/s\n", pthr->tidx,
956 		div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
957 
958 	return 0;
959 }
960 
961 static void perf_clear_test(struct perf_thread *pthr)
962 {
963 	struct perf_ctx *perf = pthr->perf;
964 
965 	if (!use_dma)
966 		goto no_dma_notify;
967 
968 	/*
969 	 * If test finished without errors, termination isn't needed.
970 	 * We call it anyway just to be sure of the transfers completion.
971 	 */
972 	(void)dmaengine_terminate_sync(pthr->dma_chan);
973 
974 	dma_release_channel(pthr->dma_chan);
975 
976 no_dma_notify:
977 	atomic_dec(&perf->tsync);
978 	wake_up(&perf->twait);
979 	kfree(pthr->src);
980 }
981 
982 static void perf_thread_work(struct work_struct *work)
983 {
984 	struct perf_thread *pthr = to_thread_work(work);
985 	int ret;
986 
987 	/*
988 	 * Perform stages in compliance with use_dma flag value.
989 	 * Test status is changed only if error happened, otherwise
990 	 * status -ENODATA is kept while test is on-fly. Results
991 	 * synchronization is performed only if test fininshed
992 	 * without an error or interruption.
993 	 */
994 	ret = perf_init_test(pthr);
995 	if (ret) {
996 		pthr->status = ret;
997 		return;
998 	}
999 
1000 	ret = perf_run_test(pthr);
1001 	if (ret) {
1002 		pthr->status = ret;
1003 		goto err_clear_test;
1004 	}
1005 
1006 	pthr->status = perf_sync_test(pthr);
1007 
1008 err_clear_test:
1009 	perf_clear_test(pthr);
1010 }
1011 
1012 static int perf_set_tcnt(struct perf_ctx *perf, u8 tcnt)
1013 {
1014 	if (tcnt == 0 || tcnt > MAX_THREADS_CNT)
1015 		return -EINVAL;
1016 
1017 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1018 		return -EBUSY;
1019 
1020 	perf->tcnt = tcnt;
1021 
1022 	clear_bit_unlock(0, &perf->busy_flag);
1023 
1024 	return 0;
1025 }
1026 
1027 static void perf_terminate_test(struct perf_ctx *perf)
1028 {
1029 	int tidx;
1030 
1031 	atomic_set(&perf->tsync, -1);
1032 	wake_up(&perf->twait);
1033 
1034 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1035 		wake_up(&perf->threads[tidx].dma_wait);
1036 		cancel_work_sync(&perf->threads[tidx].work);
1037 	}
1038 }
1039 
1040 static int perf_submit_test(struct perf_peer *peer)
1041 {
1042 	struct perf_ctx *perf = peer->perf;
1043 	struct perf_thread *pthr;
1044 	int tidx, ret;
1045 
1046 	if (!test_bit(PERF_STS_DONE, &peer->sts))
1047 		return -ENOLINK;
1048 
1049 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1050 		return -EBUSY;
1051 
1052 	perf->test_peer = peer;
1053 	atomic_set(&perf->tsync, perf->tcnt);
1054 
1055 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1056 		pthr = &perf->threads[tidx];
1057 
1058 		pthr->status = -ENODATA;
1059 		pthr->copied = 0;
1060 		pthr->duration = ktime_set(0, 0);
1061 		if (tidx < perf->tcnt)
1062 			(void)queue_work(perf_wq, &pthr->work);
1063 	}
1064 
1065 	ret = wait_event_interruptible(perf->twait,
1066 				       atomic_read(&perf->tsync) <= 0);
1067 	if (ret == -ERESTARTSYS) {
1068 		perf_terminate_test(perf);
1069 		ret = -EINTR;
1070 	}
1071 
1072 	clear_bit_unlock(0, &perf->busy_flag);
1073 
1074 	return ret;
1075 }
1076 
1077 static int perf_read_stats(struct perf_ctx *perf, char *buf,
1078 			   size_t size, ssize_t *pos)
1079 {
1080 	struct perf_thread *pthr;
1081 	int tidx;
1082 
1083 	if (test_and_set_bit_lock(0, &perf->busy_flag))
1084 		return -EBUSY;
1085 
1086 	(*pos) += scnprintf(buf + *pos, size - *pos,
1087 		"    Peer %d test statistics:\n", perf->test_peer->pidx);
1088 
1089 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1090 		pthr = &perf->threads[tidx];
1091 
1092 		if (pthr->status == -ENODATA)
1093 			continue;
1094 
1095 		if (pthr->status) {
1096 			(*pos) += scnprintf(buf + *pos, size - *pos,
1097 				"%d: error status %d\n", tidx, pthr->status);
1098 			continue;
1099 		}
1100 
1101 		(*pos) += scnprintf(buf + *pos, size - *pos,
1102 			"%d: copied %llu bytes in %llu usecs, %llu MBytes/s\n",
1103 			tidx, pthr->copied, ktime_to_us(pthr->duration),
1104 			div64_u64(pthr->copied, ktime_to_us(pthr->duration)));
1105 	}
1106 
1107 	clear_bit_unlock(0, &perf->busy_flag);
1108 
1109 	return 0;
1110 }
1111 
1112 static void perf_init_threads(struct perf_ctx *perf)
1113 {
1114 	struct perf_thread *pthr;
1115 	int tidx;
1116 
1117 	perf->tcnt = DEF_THREADS_CNT;
1118 	perf->test_peer = &perf->peers[0];
1119 	init_waitqueue_head(&perf->twait);
1120 
1121 	for (tidx = 0; tidx < MAX_THREADS_CNT; tidx++) {
1122 		pthr = &perf->threads[tidx];
1123 
1124 		pthr->perf = perf;
1125 		pthr->tidx = tidx;
1126 		pthr->status = -ENODATA;
1127 		init_waitqueue_head(&pthr->dma_wait);
1128 		INIT_WORK(&pthr->work, perf_thread_work);
1129 	}
1130 }
1131 
1132 static void perf_clear_threads(struct perf_ctx *perf)
1133 {
1134 	perf_terminate_test(perf);
1135 }
1136 
1137 /*==============================================================================
1138  *                               DebugFS nodes
1139  *==============================================================================
1140  */
1141 
1142 static ssize_t perf_dbgfs_read_info(struct file *filep, char __user *ubuf,
1143 				    size_t size, loff_t *offp)
1144 {
1145 	struct perf_ctx *perf = filep->private_data;
1146 	struct perf_peer *peer;
1147 	size_t buf_size;
1148 	ssize_t pos = 0;
1149 	int ret, pidx;
1150 	char *buf;
1151 
1152 	buf_size = min_t(size_t, size, 0x1000U);
1153 
1154 	buf = kmalloc(buf_size, GFP_KERNEL);
1155 	if (!buf)
1156 		return -ENOMEM;
1157 
1158 	pos += scnprintf(buf + pos, buf_size - pos,
1159 		"    Performance measuring tool info:\n\n");
1160 
1161 	pos += scnprintf(buf + pos, buf_size - pos,
1162 		"Local port %d, Global index %d\n", ntb_port_number(perf->ntb),
1163 		perf->gidx);
1164 	pos += scnprintf(buf + pos, buf_size - pos, "Test status: ");
1165 	if (test_bit(0, &perf->busy_flag)) {
1166 		pos += scnprintf(buf + pos, buf_size - pos,
1167 			"on-fly with port %d (%d)\n",
1168 			ntb_peer_port_number(perf->ntb, perf->test_peer->pidx),
1169 			perf->test_peer->pidx);
1170 	} else {
1171 		pos += scnprintf(buf + pos, buf_size - pos, "idle\n");
1172 	}
1173 
1174 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1175 		peer = &perf->peers[pidx];
1176 
1177 		pos += scnprintf(buf + pos, buf_size - pos,
1178 			"Port %d (%d), Global index %d:\n",
1179 			ntb_peer_port_number(perf->ntb, peer->pidx), peer->pidx,
1180 			peer->gidx);
1181 
1182 		pos += scnprintf(buf + pos, buf_size - pos,
1183 			"\tLink status: %s\n",
1184 			test_bit(PERF_STS_LNKUP, &peer->sts) ? "up" : "down");
1185 
1186 		pos += scnprintf(buf + pos, buf_size - pos,
1187 			"\tOut buffer addr 0x%pK\n", peer->outbuf);
1188 
1189 		pos += scnprintf(buf + pos, buf_size - pos,
1190 			"\tOut buffer size %pa\n", &peer->outbuf_size);
1191 
1192 		pos += scnprintf(buf + pos, buf_size - pos,
1193 			"\tOut buffer xlat 0x%016llx[p]\n", peer->outbuf_xlat);
1194 
1195 		if (!peer->inbuf) {
1196 			pos += scnprintf(buf + pos, buf_size - pos,
1197 				"\tIn buffer addr: unallocated\n");
1198 			continue;
1199 		}
1200 
1201 		pos += scnprintf(buf + pos, buf_size - pos,
1202 			"\tIn buffer addr 0x%pK\n", peer->inbuf);
1203 
1204 		pos += scnprintf(buf + pos, buf_size - pos,
1205 			"\tIn buffer size %pa\n", &peer->inbuf_size);
1206 
1207 		pos += scnprintf(buf + pos, buf_size - pos,
1208 			"\tIn buffer xlat %pad[p]\n", &peer->inbuf_xlat);
1209 	}
1210 
1211 	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
1212 	kfree(buf);
1213 
1214 	return ret;
1215 }
1216 
1217 static const struct file_operations perf_dbgfs_info = {
1218 	.open = simple_open,
1219 	.read = perf_dbgfs_read_info
1220 };
1221 
1222 static ssize_t perf_dbgfs_read_run(struct file *filep, char __user *ubuf,
1223 				   size_t size, loff_t *offp)
1224 {
1225 	struct perf_ctx *perf = filep->private_data;
1226 	ssize_t ret, pos = 0;
1227 	char *buf;
1228 
1229 	buf = kmalloc(PERF_BUF_LEN, GFP_KERNEL);
1230 	if (!buf)
1231 		return -ENOMEM;
1232 
1233 	ret = perf_read_stats(perf, buf, PERF_BUF_LEN, &pos);
1234 	if (ret)
1235 		goto err_free;
1236 
1237 	ret = simple_read_from_buffer(ubuf, size, offp, buf, pos);
1238 err_free:
1239 	kfree(buf);
1240 
1241 	return ret;
1242 }
1243 
1244 static ssize_t perf_dbgfs_write_run(struct file *filep, const char __user *ubuf,
1245 				    size_t size, loff_t *offp)
1246 {
1247 	struct perf_ctx *perf = filep->private_data;
1248 	struct perf_peer *peer;
1249 	int pidx, ret;
1250 
1251 	ret = kstrtoint_from_user(ubuf, size, 0, &pidx);
1252 	if (ret)
1253 		return ret;
1254 
1255 	if (pidx < 0 || pidx >= perf->pcnt)
1256 		return -EINVAL;
1257 
1258 	peer = &perf->peers[pidx];
1259 
1260 	ret = perf_submit_test(peer);
1261 	if (ret)
1262 		return ret;
1263 
1264 	return size;
1265 }
1266 
1267 static const struct file_operations perf_dbgfs_run = {
1268 	.open = simple_open,
1269 	.read = perf_dbgfs_read_run,
1270 	.write = perf_dbgfs_write_run
1271 };
1272 
1273 static ssize_t perf_dbgfs_read_tcnt(struct file *filep, char __user *ubuf,
1274 				    size_t size, loff_t *offp)
1275 {
1276 	struct perf_ctx *perf = filep->private_data;
1277 	char buf[8];
1278 	ssize_t pos;
1279 
1280 	pos = scnprintf(buf, sizeof(buf), "%hhu\n", perf->tcnt);
1281 
1282 	return simple_read_from_buffer(ubuf, size, offp, buf, pos);
1283 }
1284 
1285 static ssize_t perf_dbgfs_write_tcnt(struct file *filep,
1286 				     const char __user *ubuf,
1287 				     size_t size, loff_t *offp)
1288 {
1289 	struct perf_ctx *perf = filep->private_data;
1290 	int ret;
1291 	u8 val;
1292 
1293 	ret = kstrtou8_from_user(ubuf, size, 0, &val);
1294 	if (ret)
1295 		return ret;
1296 
1297 	ret = perf_set_tcnt(perf, val);
1298 	if (ret)
1299 		return ret;
1300 
1301 	return size;
1302 }
1303 
1304 static const struct file_operations perf_dbgfs_tcnt = {
1305 	.open = simple_open,
1306 	.read = perf_dbgfs_read_tcnt,
1307 	.write = perf_dbgfs_write_tcnt
1308 };
1309 
1310 static void perf_setup_dbgfs(struct perf_ctx *perf)
1311 {
1312 	struct pci_dev *pdev = perf->ntb->pdev;
1313 
1314 	perf->dbgfs_dir = debugfs_create_dir(pci_name(pdev), perf_dbgfs_topdir);
1315 	if (!perf->dbgfs_dir) {
1316 		dev_warn(&perf->ntb->dev, "DebugFS unsupported\n");
1317 		return;
1318 	}
1319 
1320 	debugfs_create_file("info", 0600, perf->dbgfs_dir, perf,
1321 			    &perf_dbgfs_info);
1322 
1323 	debugfs_create_file("run", 0600, perf->dbgfs_dir, perf,
1324 			    &perf_dbgfs_run);
1325 
1326 	debugfs_create_file("threads_count", 0600, perf->dbgfs_dir, perf,
1327 			    &perf_dbgfs_tcnt);
1328 
1329 	/* They are made read-only for test exec safety and integrity */
1330 	debugfs_create_u8("chunk_order", 0500, perf->dbgfs_dir, &chunk_order);
1331 
1332 	debugfs_create_u8("total_order", 0500, perf->dbgfs_dir, &total_order);
1333 
1334 	debugfs_create_bool("use_dma", 0500, perf->dbgfs_dir, &use_dma);
1335 }
1336 
1337 static void perf_clear_dbgfs(struct perf_ctx *perf)
1338 {
1339 	debugfs_remove_recursive(perf->dbgfs_dir);
1340 }
1341 
1342 /*==============================================================================
1343  *                        Basic driver initialization
1344  *==============================================================================
1345  */
1346 
1347 static struct perf_ctx *perf_create_data(struct ntb_dev *ntb)
1348 {
1349 	struct perf_ctx *perf;
1350 
1351 	perf = devm_kzalloc(&ntb->dev, sizeof(*perf), GFP_KERNEL);
1352 	if (!perf)
1353 		return ERR_PTR(-ENOMEM);
1354 
1355 	perf->pcnt = ntb_peer_port_count(ntb);
1356 	perf->peers = devm_kcalloc(&ntb->dev, perf->pcnt, sizeof(*perf->peers),
1357 				  GFP_KERNEL);
1358 	if (!perf->peers)
1359 		return ERR_PTR(-ENOMEM);
1360 
1361 	perf->ntb = ntb;
1362 
1363 	return perf;
1364 }
1365 
1366 static int perf_setup_peer_mw(struct perf_peer *peer)
1367 {
1368 	struct perf_ctx *perf = peer->perf;
1369 	phys_addr_t phys_addr;
1370 	int ret;
1371 
1372 	/* Get outbound MW parameters and map it */
1373 	ret = ntb_peer_mw_get_addr(perf->ntb, peer->gidx, &phys_addr,
1374 				   &peer->outbuf_size);
1375 	if (ret)
1376 		return ret;
1377 
1378 	peer->outbuf = devm_ioremap_wc(&perf->ntb->dev, phys_addr,
1379 					peer->outbuf_size);
1380 	if (!peer->outbuf)
1381 		return -ENOMEM;
1382 
1383 	if (max_mw_size && peer->outbuf_size > max_mw_size) {
1384 		peer->outbuf_size = max_mw_size;
1385 		dev_warn(&peer->perf->ntb->dev,
1386 			"Peer %d outbuf reduced to %pa\n", peer->pidx,
1387 			&peer->outbuf_size);
1388 	}
1389 
1390 	return 0;
1391 }
1392 
1393 static int perf_init_peers(struct perf_ctx *perf)
1394 {
1395 	struct perf_peer *peer;
1396 	int pidx, lport, ret;
1397 
1398 	lport = ntb_port_number(perf->ntb);
1399 	perf->gidx = -1;
1400 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1401 		peer = &perf->peers[pidx];
1402 
1403 		peer->perf = perf;
1404 		peer->pidx = pidx;
1405 		if (lport < ntb_peer_port_number(perf->ntb, pidx)) {
1406 			if (perf->gidx == -1)
1407 				perf->gidx = pidx;
1408 			peer->gidx = pidx + 1;
1409 		} else {
1410 			peer->gidx = pidx;
1411 		}
1412 		INIT_WORK(&peer->service, perf_service_work);
1413 	}
1414 	if (perf->gidx == -1)
1415 		perf->gidx = pidx;
1416 
1417 	for (pidx = 0; pidx < perf->pcnt; pidx++) {
1418 		ret = perf_setup_peer_mw(&perf->peers[pidx]);
1419 		if (ret)
1420 			return ret;
1421 	}
1422 
1423 	dev_dbg(&perf->ntb->dev, "Global port index %d\n", perf->gidx);
1424 
1425 	return 0;
1426 }
1427 
1428 static int perf_probe(struct ntb_client *client, struct ntb_dev *ntb)
1429 {
1430 	struct perf_ctx *perf;
1431 	int ret;
1432 
1433 	perf = perf_create_data(ntb);
1434 	if (IS_ERR(perf))
1435 		return PTR_ERR(perf);
1436 
1437 	ret = perf_init_peers(perf);
1438 	if (ret)
1439 		return ret;
1440 
1441 	perf_init_threads(perf);
1442 
1443 	ret = perf_init_service(perf);
1444 	if (ret)
1445 		return ret;
1446 
1447 	ret = perf_enable_service(perf);
1448 	if (ret)
1449 		return ret;
1450 
1451 	perf_setup_dbgfs(perf);
1452 
1453 	return 0;
1454 }
1455 
1456 static void perf_remove(struct ntb_client *client, struct ntb_dev *ntb)
1457 {
1458 	struct perf_ctx *perf = ntb->ctx;
1459 
1460 	perf_clear_dbgfs(perf);
1461 
1462 	perf_disable_service(perf);
1463 
1464 	perf_clear_threads(perf);
1465 }
1466 
1467 static struct ntb_client perf_client = {
1468 	.ops = {
1469 		.probe = perf_probe,
1470 		.remove = perf_remove
1471 	}
1472 };
1473 
1474 static int __init perf_init(void)
1475 {
1476 	int ret;
1477 
1478 	if (chunk_order > MAX_CHUNK_ORDER) {
1479 		chunk_order = MAX_CHUNK_ORDER;
1480 		pr_info("Chunk order reduced to %hhu\n", chunk_order);
1481 	}
1482 
1483 	if (total_order < chunk_order) {
1484 		total_order = chunk_order;
1485 		pr_info("Total data order reduced to %hhu\n", total_order);
1486 	}
1487 
1488 	perf_wq = alloc_workqueue("perf_wq", WQ_UNBOUND | WQ_SYSFS, 0);
1489 	if (!perf_wq)
1490 		return -ENOMEM;
1491 
1492 	if (debugfs_initialized())
1493 		perf_dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
1494 
1495 	ret = ntb_register_client(&perf_client);
1496 	if (ret) {
1497 		debugfs_remove_recursive(perf_dbgfs_topdir);
1498 		destroy_workqueue(perf_wq);
1499 	}
1500 
1501 	return ret;
1502 }
1503 module_init(perf_init);
1504 
1505 static void __exit perf_exit(void)
1506 {
1507 	ntb_unregister_client(&perf_client);
1508 	debugfs_remove_recursive(perf_dbgfs_topdir);
1509 	destroy_workqueue(perf_wq);
1510 }
1511 module_exit(perf_exit);
1512 
1513