1// SPDX-License-Identifier: GPL-2.0-only
2/****************************************************************************
3 * Driver for Solarflare network controllers and boards
4 * Copyright 2018 Solarflare Communications Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation, incorporated herein by reference.
9 */
10
11#include "net_driver.h"
12#include <linux/module.h>
13#include <linux/filter.h>
14#include "efx_channels.h"
15#include "efx.h"
16#include "efx_common.h"
17#include "tx_common.h"
18#include "rx_common.h"
19#include "nic.h"
20#include "sriov.h"
21#include "workarounds.h"
22
23/* This is the first interrupt mode to try out of:
24 * 0 => MSI-X
25 * 1 => MSI
26 * 2 => legacy
27 */
28unsigned int efx_siena_interrupt_mode = EFX_INT_MODE_MSIX;
29
30/* This is the requested number of CPUs to use for Receive-Side Scaling (RSS),
31 * i.e. the number of CPUs among which we may distribute simultaneous
32 * interrupt handling.
33 *
34 * Cards without MSI-X will only target one CPU via legacy or MSI interrupt.
35 * The default (0) means to assign an interrupt to each core.
36 */
37unsigned int efx_siena_rss_cpus;
38
39static unsigned int irq_adapt_low_thresh = 8000;
40module_param(irq_adapt_low_thresh, uint, 0644);
41MODULE_PARM_DESC(irq_adapt_low_thresh,
42 "Threshold score for reducing IRQ moderation");
43
44static unsigned int irq_adapt_high_thresh = 16000;
45module_param(irq_adapt_high_thresh, uint, 0644);
46MODULE_PARM_DESC(irq_adapt_high_thresh,
47 "Threshold score for increasing IRQ moderation");
48
49static const struct efx_channel_type efx_default_channel_type;
50
51/*************
52 * INTERRUPTS
53 *************/
54
55static unsigned int count_online_cores(struct efx_nic *efx, bool local_node)
56{
57 cpumask_var_t filter_mask;
58 unsigned int count;
59 int cpu;
60
61 if (unlikely(!zalloc_cpumask_var(&filter_mask, GFP_KERNEL))) {
62 netif_warn(efx, probe, efx->net_dev,
63 "RSS disabled due to allocation failure\n");
64 return 1;
65 }
66
67 cpumask_copy(dstp: filter_mask, cpu_online_mask);
68 if (local_node)
69 cpumask_and(dstp: filter_mask, src1p: filter_mask,
70 src2p: cpumask_of_pcibus(bus: efx->pci_dev->bus));
71
72 count = 0;
73 for_each_cpu(cpu, filter_mask) {
74 ++count;
75 cpumask_andnot(dstp: filter_mask, src1p: filter_mask, topology_sibling_cpumask(cpu));
76 }
77
78 free_cpumask_var(mask: filter_mask);
79
80 return count;
81}
82
83static unsigned int efx_wanted_parallelism(struct efx_nic *efx)
84{
85 unsigned int count;
86
87 if (efx_siena_rss_cpus) {
88 count = efx_siena_rss_cpus;
89 } else {
90 count = count_online_cores(efx, local_node: true);
91
92 /* If no online CPUs in local node, fallback to any online CPUs */
93 if (count == 0)
94 count = count_online_cores(efx, local_node: false);
95 }
96
97 if (count > EFX_MAX_RX_QUEUES) {
98 netif_cond_dbg(efx, probe, efx->net_dev, !efx_siena_rss_cpus,
99 warn,
100 "Reducing number of rx queues from %u to %u.\n",
101 count, EFX_MAX_RX_QUEUES);
102 count = EFX_MAX_RX_QUEUES;
103 }
104
105 /* If RSS is requested for the PF *and* VFs then we can't write RSS
106 * table entries that are inaccessible to VFs
107 */
108#ifdef CONFIG_SFC_SIENA_SRIOV
109 if (efx->type->sriov_wanted) {
110 if (efx->type->sriov_wanted(efx) && efx_vf_size(efx) > 1 &&
111 count > efx_vf_size(efx)) {
112 netif_warn(efx, probe, efx->net_dev,
113 "Reducing number of RSS channels from %u to %u for "
114 "VF support. Increase vf-msix-limit to use more "
115 "channels on the PF.\n",
116 count, efx_vf_size(efx));
117 count = efx_vf_size(efx);
118 }
119 }
120#endif
121
122 return count;
123}
124
125static int efx_allocate_msix_channels(struct efx_nic *efx,
126 unsigned int max_channels,
127 unsigned int extra_channels,
128 unsigned int parallelism)
129{
130 unsigned int n_channels = parallelism;
131 int vec_count;
132 int tx_per_ev;
133 int n_xdp_tx;
134 int n_xdp_ev;
135
136 if (efx_siena_separate_tx_channels)
137 n_channels *= 2;
138 n_channels += extra_channels;
139
140 /* To allow XDP transmit to happen from arbitrary NAPI contexts
141 * we allocate a TX queue per CPU. We share event queues across
142 * multiple tx queues, assuming tx and ev queues are both
143 * maximum size.
144 */
145 tx_per_ev = EFX_MAX_EVQ_SIZE / EFX_TXQ_MAX_ENT(efx);
146 tx_per_ev = min(tx_per_ev, EFX_MAX_TXQ_PER_CHANNEL);
147 n_xdp_tx = num_possible_cpus();
148 n_xdp_ev = DIV_ROUND_UP(n_xdp_tx, tx_per_ev);
149
150 vec_count = pci_msix_vec_count(dev: efx->pci_dev);
151 if (vec_count < 0)
152 return vec_count;
153
154 max_channels = min_t(unsigned int, vec_count, max_channels);
155
156 /* Check resources.
157 * We need a channel per event queue, plus a VI per tx queue.
158 * This may be more pessimistic than it needs to be.
159 */
160 if (n_channels >= max_channels) {
161 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_BORROWED;
162 netif_warn(efx, drv, efx->net_dev,
163 "Insufficient resources for %d XDP event queues (%d other channels, max %d)\n",
164 n_xdp_ev, n_channels, max_channels);
165 netif_warn(efx, drv, efx->net_dev,
166 "XDP_TX and XDP_REDIRECT might decrease device's performance\n");
167 } else if (n_channels + n_xdp_tx > efx->max_vis) {
168 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_BORROWED;
169 netif_warn(efx, drv, efx->net_dev,
170 "Insufficient resources for %d XDP TX queues (%d other channels, max VIs %d)\n",
171 n_xdp_tx, n_channels, efx->max_vis);
172 netif_warn(efx, drv, efx->net_dev,
173 "XDP_TX and XDP_REDIRECT might decrease device's performance\n");
174 } else if (n_channels + n_xdp_ev > max_channels) {
175 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_SHARED;
176 netif_warn(efx, drv, efx->net_dev,
177 "Insufficient resources for %d XDP event queues (%d other channels, max %d)\n",
178 n_xdp_ev, n_channels, max_channels);
179
180 n_xdp_ev = max_channels - n_channels;
181 netif_warn(efx, drv, efx->net_dev,
182 "XDP_TX and XDP_REDIRECT will work with reduced performance (%d cpus/tx_queue)\n",
183 DIV_ROUND_UP(n_xdp_tx, tx_per_ev * n_xdp_ev));
184 } else {
185 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_DEDICATED;
186 }
187
188 if (efx->xdp_txq_queues_mode != EFX_XDP_TX_QUEUES_BORROWED) {
189 efx->n_xdp_channels = n_xdp_ev;
190 efx->xdp_tx_per_channel = tx_per_ev;
191 efx->xdp_tx_queue_count = n_xdp_tx;
192 n_channels += n_xdp_ev;
193 netif_dbg(efx, drv, efx->net_dev,
194 "Allocating %d TX and %d event queues for XDP\n",
195 n_xdp_ev * tx_per_ev, n_xdp_ev);
196 } else {
197 efx->n_xdp_channels = 0;
198 efx->xdp_tx_per_channel = 0;
199 efx->xdp_tx_queue_count = n_xdp_tx;
200 }
201
202 if (vec_count < n_channels) {
203 netif_err(efx, drv, efx->net_dev,
204 "WARNING: Insufficient MSI-X vectors available (%d < %u).\n",
205 vec_count, n_channels);
206 netif_err(efx, drv, efx->net_dev,
207 "WARNING: Performance may be reduced.\n");
208 n_channels = vec_count;
209 }
210
211 n_channels = min(n_channels, max_channels);
212
213 efx->n_channels = n_channels;
214
215 /* Ignore XDP tx channels when creating rx channels. */
216 n_channels -= efx->n_xdp_channels;
217
218 if (efx_siena_separate_tx_channels) {
219 efx->n_tx_channels =
220 min(max(n_channels / 2, 1U),
221 efx->max_tx_channels);
222 efx->tx_channel_offset =
223 n_channels - efx->n_tx_channels;
224 efx->n_rx_channels =
225 max(n_channels -
226 efx->n_tx_channels, 1U);
227 } else {
228 efx->n_tx_channels = min(n_channels, efx->max_tx_channels);
229 efx->tx_channel_offset = 0;
230 efx->n_rx_channels = n_channels;
231 }
232
233 efx->n_rx_channels = min(efx->n_rx_channels, parallelism);
234 efx->n_tx_channels = min(efx->n_tx_channels, parallelism);
235
236 efx->xdp_channel_offset = n_channels;
237
238 netif_dbg(efx, drv, efx->net_dev,
239 "Allocating %u RX channels\n",
240 efx->n_rx_channels);
241
242 return efx->n_channels;
243}
244
245/* Probe the number and type of interrupts we are able to obtain, and
246 * the resulting numbers of channels and RX queues.
247 */
248int efx_siena_probe_interrupts(struct efx_nic *efx)
249{
250 unsigned int extra_channels = 0;
251 unsigned int rss_spread;
252 unsigned int i, j;
253 int rc;
254
255 for (i = 0; i < EFX_MAX_EXTRA_CHANNELS; i++)
256 if (efx->extra_channel_type[i])
257 ++extra_channels;
258
259 if (efx->interrupt_mode == EFX_INT_MODE_MSIX) {
260 unsigned int parallelism = efx_wanted_parallelism(efx);
261 struct msix_entry xentries[EFX_MAX_CHANNELS];
262 unsigned int n_channels;
263
264 rc = efx_allocate_msix_channels(efx, max_channels: efx->max_channels,
265 extra_channels, parallelism);
266 if (rc >= 0) {
267 n_channels = rc;
268 for (i = 0; i < n_channels; i++)
269 xentries[i].entry = i;
270 rc = pci_enable_msix_range(dev: efx->pci_dev, entries: xentries, minvec: 1,
271 maxvec: n_channels);
272 }
273 if (rc < 0) {
274 /* Fall back to single channel MSI */
275 netif_err(efx, drv, efx->net_dev,
276 "could not enable MSI-X\n");
277 if (efx->type->min_interrupt_mode >= EFX_INT_MODE_MSI)
278 efx->interrupt_mode = EFX_INT_MODE_MSI;
279 else
280 return rc;
281 } else if (rc < n_channels) {
282 netif_err(efx, drv, efx->net_dev,
283 "WARNING: Insufficient MSI-X vectors"
284 " available (%d < %u).\n", rc, n_channels);
285 netif_err(efx, drv, efx->net_dev,
286 "WARNING: Performance may be reduced.\n");
287 n_channels = rc;
288 }
289
290 if (rc > 0) {
291 for (i = 0; i < efx->n_channels; i++)
292 efx_get_channel(efx, index: i)->irq =
293 xentries[i].vector;
294 }
295 }
296
297 /* Try single interrupt MSI */
298 if (efx->interrupt_mode == EFX_INT_MODE_MSI) {
299 efx->n_channels = 1;
300 efx->n_rx_channels = 1;
301 efx->n_tx_channels = 1;
302 efx->tx_channel_offset = 0;
303 efx->n_xdp_channels = 0;
304 efx->xdp_channel_offset = efx->n_channels;
305 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_BORROWED;
306 rc = pci_enable_msi(dev: efx->pci_dev);
307 if (rc == 0) {
308 efx_get_channel(efx, index: 0)->irq = efx->pci_dev->irq;
309 } else {
310 netif_err(efx, drv, efx->net_dev,
311 "could not enable MSI\n");
312 if (efx->type->min_interrupt_mode >= EFX_INT_MODE_LEGACY)
313 efx->interrupt_mode = EFX_INT_MODE_LEGACY;
314 else
315 return rc;
316 }
317 }
318
319 /* Assume legacy interrupts */
320 if (efx->interrupt_mode == EFX_INT_MODE_LEGACY) {
321 efx->n_channels = 1 + (efx_siena_separate_tx_channels ? 1 : 0);
322 efx->n_rx_channels = 1;
323 efx->n_tx_channels = 1;
324 efx->tx_channel_offset = efx_siena_separate_tx_channels ? 1 : 0;
325 efx->n_xdp_channels = 0;
326 efx->xdp_channel_offset = efx->n_channels;
327 efx->xdp_txq_queues_mode = EFX_XDP_TX_QUEUES_BORROWED;
328 efx->legacy_irq = efx->pci_dev->irq;
329 }
330
331 /* Assign extra channels if possible, before XDP channels */
332 efx->n_extra_tx_channels = 0;
333 j = efx->xdp_channel_offset;
334 for (i = 0; i < EFX_MAX_EXTRA_CHANNELS; i++) {
335 if (!efx->extra_channel_type[i])
336 continue;
337 if (j <= efx->tx_channel_offset + efx->n_tx_channels) {
338 efx->extra_channel_type[i]->handle_no_channel(efx);
339 } else {
340 --j;
341 efx_get_channel(efx, index: j)->type =
342 efx->extra_channel_type[i];
343 if (efx_channel_has_tx_queues(channel: efx_get_channel(efx, index: j)))
344 efx->n_extra_tx_channels++;
345 }
346 }
347
348 rss_spread = efx->n_rx_channels;
349 /* RSS might be usable on VFs even if it is disabled on the PF */
350#ifdef CONFIG_SFC_SIENA_SRIOV
351 if (efx->type->sriov_wanted) {
352 efx->rss_spread = ((rss_spread > 1 ||
353 !efx->type->sriov_wanted(efx)) ?
354 rss_spread : efx_vf_size(efx));
355 return 0;
356 }
357#endif
358 efx->rss_spread = rss_spread;
359
360 return 0;
361}
362
363#if defined(CONFIG_SMP)
364void efx_siena_set_interrupt_affinity(struct efx_nic *efx)
365{
366 const struct cpumask *numa_mask = cpumask_of_pcibus(bus: efx->pci_dev->bus);
367 struct efx_channel *channel;
368 unsigned int cpu;
369
370 /* If no online CPUs in local node, fallback to any online CPU */
371 if (cpumask_first_and(cpu_online_mask, srcp2: numa_mask) >= nr_cpu_ids)
372 numa_mask = cpu_online_mask;
373
374 cpu = -1;
375 efx_for_each_channel(channel, efx) {
376 cpu = cpumask_next_and(n: cpu, cpu_online_mask, src2p: numa_mask);
377 if (cpu >= nr_cpu_ids)
378 cpu = cpumask_first_and(cpu_online_mask, srcp2: numa_mask);
379 irq_set_affinity_hint(irq: channel->irq, cpumask_of(cpu));
380 }
381}
382
383void efx_siena_clear_interrupt_affinity(struct efx_nic *efx)
384{
385 struct efx_channel *channel;
386
387 efx_for_each_channel(channel, efx)
388 irq_set_affinity_hint(irq: channel->irq, NULL);
389}
390#else
391void
392efx_siena_set_interrupt_affinity(struct efx_nic *efx __always_unused)
393{
394}
395
396void
397efx_siena_clear_interrupt_affinity(struct efx_nic *efx __always_unused)
398{
399}
400#endif /* CONFIG_SMP */
401
402void efx_siena_remove_interrupts(struct efx_nic *efx)
403{
404 struct efx_channel *channel;
405
406 /* Remove MSI/MSI-X interrupts */
407 efx_for_each_channel(channel, efx)
408 channel->irq = 0;
409 pci_disable_msi(dev: efx->pci_dev);
410 pci_disable_msix(dev: efx->pci_dev);
411
412 /* Remove legacy interrupt */
413 efx->legacy_irq = 0;
414}
415
416/***************
417 * EVENT QUEUES
418 ***************/
419
420/* Create event queue
421 * Event queue memory allocations are done only once. If the channel
422 * is reset, the memory buffer will be reused; this guards against
423 * errors during channel reset and also simplifies interrupt handling.
424 */
425static int efx_probe_eventq(struct efx_channel *channel)
426{
427 struct efx_nic *efx = channel->efx;
428 unsigned long entries;
429
430 netif_dbg(efx, probe, efx->net_dev,
431 "chan %d create event queue\n", channel->channel);
432
433 /* Build an event queue with room for one event per tx and rx buffer,
434 * plus some extra for link state events and MCDI completions.
435 */
436 entries = roundup_pow_of_two(efx->rxq_entries + efx->txq_entries + 128);
437 EFX_WARN_ON_PARANOID(entries > EFX_MAX_EVQ_SIZE);
438 channel->eventq_mask = max(entries, EFX_MIN_EVQ_SIZE) - 1;
439
440 return efx_nic_probe_eventq(channel);
441}
442
443/* Prepare channel's event queue */
444static int efx_init_eventq(struct efx_channel *channel)
445{
446 struct efx_nic *efx = channel->efx;
447 int rc;
448
449 EFX_WARN_ON_PARANOID(channel->eventq_init);
450
451 netif_dbg(efx, drv, efx->net_dev,
452 "chan %d init event queue\n", channel->channel);
453
454 rc = efx_nic_init_eventq(channel);
455 if (rc == 0) {
456 efx->type->push_irq_moderation(channel);
457 channel->eventq_read_ptr = 0;
458 channel->eventq_init = true;
459 }
460 return rc;
461}
462
463/* Enable event queue processing and NAPI */
464void efx_siena_start_eventq(struct efx_channel *channel)
465{
466 netif_dbg(channel->efx, ifup, channel->efx->net_dev,
467 "chan %d start event queue\n", channel->channel);
468
469 /* Make sure the NAPI handler sees the enabled flag set */
470 channel->enabled = true;
471 smp_wmb();
472
473 napi_enable(n: &channel->napi_str);
474 efx_nic_eventq_read_ack(channel);
475}
476
477/* Disable event queue processing and NAPI */
478void efx_siena_stop_eventq(struct efx_channel *channel)
479{
480 if (!channel->enabled)
481 return;
482
483 napi_disable(n: &channel->napi_str);
484 channel->enabled = false;
485}
486
487static void efx_fini_eventq(struct efx_channel *channel)
488{
489 if (!channel->eventq_init)
490 return;
491
492 netif_dbg(channel->efx, drv, channel->efx->net_dev,
493 "chan %d fini event queue\n", channel->channel);
494
495 efx_nic_fini_eventq(channel);
496 channel->eventq_init = false;
497}
498
499static void efx_remove_eventq(struct efx_channel *channel)
500{
501 netif_dbg(channel->efx, drv, channel->efx->net_dev,
502 "chan %d remove event queue\n", channel->channel);
503
504 efx_nic_remove_eventq(channel);
505}
506
507/**************************************************************************
508 *
509 * Channel handling
510 *
511 *************************************************************************/
512
513#ifdef CONFIG_RFS_ACCEL
514static void efx_filter_rfs_expire(struct work_struct *data)
515{
516 struct delayed_work *dwork = to_delayed_work(work: data);
517 struct efx_channel *channel;
518 unsigned int time, quota;
519
520 channel = container_of(dwork, struct efx_channel, filter_work);
521 time = jiffies - channel->rfs_last_expiry;
522 quota = channel->rfs_filter_count * time / (30 * HZ);
523 if (quota >= 20 && __efx_siena_filter_rfs_expire(channel,
524 min(channel->rfs_filter_count, quota)))
525 channel->rfs_last_expiry += time;
526 /* Ensure we do more work eventually even if NAPI poll is not happening */
527 schedule_delayed_work(dwork, delay: 30 * HZ);
528}
529#endif
530
531/* Allocate and initialise a channel structure. */
532static struct efx_channel *efx_alloc_channel(struct efx_nic *efx, int i)
533{
534 struct efx_rx_queue *rx_queue;
535 struct efx_tx_queue *tx_queue;
536 struct efx_channel *channel;
537 int j;
538
539 channel = kzalloc(size: sizeof(*channel), GFP_KERNEL);
540 if (!channel)
541 return NULL;
542
543 channel->efx = efx;
544 channel->channel = i;
545 channel->type = &efx_default_channel_type;
546
547 for (j = 0; j < EFX_MAX_TXQ_PER_CHANNEL; j++) {
548 tx_queue = &channel->tx_queue[j];
549 tx_queue->efx = efx;
550 tx_queue->queue = -1;
551 tx_queue->label = j;
552 tx_queue->channel = channel;
553 }
554
555#ifdef CONFIG_RFS_ACCEL
556 INIT_DELAYED_WORK(&channel->filter_work, efx_filter_rfs_expire);
557#endif
558
559 rx_queue = &channel->rx_queue;
560 rx_queue->efx = efx;
561 timer_setup(&rx_queue->slow_fill, efx_siena_rx_slow_fill, 0);
562
563 return channel;
564}
565
566int efx_siena_init_channels(struct efx_nic *efx)
567{
568 unsigned int i;
569
570 for (i = 0; i < EFX_MAX_CHANNELS; i++) {
571 efx->channel[i] = efx_alloc_channel(efx, i);
572 if (!efx->channel[i])
573 return -ENOMEM;
574 efx->msi_context[i].efx = efx;
575 efx->msi_context[i].index = i;
576 }
577
578 /* Higher numbered interrupt modes are less capable! */
579 efx->interrupt_mode = min(efx->type->min_interrupt_mode,
580 efx_siena_interrupt_mode);
581
582 efx->max_channels = EFX_MAX_CHANNELS;
583 efx->max_tx_channels = EFX_MAX_CHANNELS;
584
585 return 0;
586}
587
588void efx_siena_fini_channels(struct efx_nic *efx)
589{
590 unsigned int i;
591
592 for (i = 0; i < EFX_MAX_CHANNELS; i++)
593 if (efx->channel[i]) {
594 kfree(objp: efx->channel[i]);
595 efx->channel[i] = NULL;
596 }
597}
598
599/* Allocate and initialise a channel structure, copying parameters
600 * (but not resources) from an old channel structure.
601 */
602static
603struct efx_channel *efx_copy_channel(const struct efx_channel *old_channel)
604{
605 struct efx_rx_queue *rx_queue;
606 struct efx_tx_queue *tx_queue;
607 struct efx_channel *channel;
608 int j;
609
610 channel = kmalloc(size: sizeof(*channel), GFP_KERNEL);
611 if (!channel)
612 return NULL;
613
614 *channel = *old_channel;
615
616 channel->napi_dev = NULL;
617 INIT_HLIST_NODE(h: &channel->napi_str.napi_hash_node);
618 channel->napi_str.napi_id = 0;
619 channel->napi_str.state = 0;
620 memset(&channel->eventq, 0, sizeof(channel->eventq));
621
622 for (j = 0; j < EFX_MAX_TXQ_PER_CHANNEL; j++) {
623 tx_queue = &channel->tx_queue[j];
624 if (tx_queue->channel)
625 tx_queue->channel = channel;
626 tx_queue->buffer = NULL;
627 tx_queue->cb_page = NULL;
628 memset(&tx_queue->txd, 0, sizeof(tx_queue->txd));
629 }
630
631 rx_queue = &channel->rx_queue;
632 rx_queue->buffer = NULL;
633 memset(&rx_queue->rxd, 0, sizeof(rx_queue->rxd));
634 timer_setup(&rx_queue->slow_fill, efx_siena_rx_slow_fill, 0);
635#ifdef CONFIG_RFS_ACCEL
636 INIT_DELAYED_WORK(&channel->filter_work, efx_filter_rfs_expire);
637#endif
638
639 return channel;
640}
641
642static int efx_probe_channel(struct efx_channel *channel)
643{
644 struct efx_tx_queue *tx_queue;
645 struct efx_rx_queue *rx_queue;
646 int rc;
647
648 netif_dbg(channel->efx, probe, channel->efx->net_dev,
649 "creating channel %d\n", channel->channel);
650
651 rc = channel->type->pre_probe(channel);
652 if (rc)
653 goto fail;
654
655 rc = efx_probe_eventq(channel);
656 if (rc)
657 goto fail;
658
659 efx_for_each_channel_tx_queue(tx_queue, channel) {
660 rc = efx_siena_probe_tx_queue(tx_queue);
661 if (rc)
662 goto fail;
663 }
664
665 efx_for_each_channel_rx_queue(rx_queue, channel) {
666 rc = efx_siena_probe_rx_queue(rx_queue);
667 if (rc)
668 goto fail;
669 }
670
671 channel->rx_list = NULL;
672
673 return 0;
674
675fail:
676 efx_siena_remove_channel(channel);
677 return rc;
678}
679
680static void efx_get_channel_name(struct efx_channel *channel, char *buf,
681 size_t len)
682{
683 struct efx_nic *efx = channel->efx;
684 const char *type;
685 int number;
686
687 number = channel->channel;
688
689 if (number >= efx->xdp_channel_offset &&
690 !WARN_ON_ONCE(!efx->n_xdp_channels)) {
691 type = "-xdp";
692 number -= efx->xdp_channel_offset;
693 } else if (efx->tx_channel_offset == 0) {
694 type = "";
695 } else if (number < efx->tx_channel_offset) {
696 type = "-rx";
697 } else {
698 type = "-tx";
699 number -= efx->tx_channel_offset;
700 }
701 snprintf(buf, size: len, fmt: "%s%s-%d", efx->name, type, number);
702}
703
704void efx_siena_set_channel_names(struct efx_nic *efx)
705{
706 struct efx_channel *channel;
707
708 efx_for_each_channel(channel, efx)
709 channel->type->get_name(channel,
710 efx->msi_context[channel->channel].name,
711 sizeof(efx->msi_context[0].name));
712}
713
714int efx_siena_probe_channels(struct efx_nic *efx)
715{
716 struct efx_channel *channel;
717 int rc;
718
719 /* Restart special buffer allocation */
720 efx->next_buffer_table = 0;
721
722 /* Probe channels in reverse, so that any 'extra' channels
723 * use the start of the buffer table. This allows the traffic
724 * channels to be resized without moving them or wasting the
725 * entries before them.
726 */
727 efx_for_each_channel_rev(channel, efx) {
728 rc = efx_probe_channel(channel);
729 if (rc) {
730 netif_err(efx, probe, efx->net_dev,
731 "failed to create channel %d\n",
732 channel->channel);
733 goto fail;
734 }
735 }
736 efx_siena_set_channel_names(efx);
737
738 return 0;
739
740fail:
741 efx_siena_remove_channels(efx);
742 return rc;
743}
744
745void efx_siena_remove_channel(struct efx_channel *channel)
746{
747 struct efx_tx_queue *tx_queue;
748 struct efx_rx_queue *rx_queue;
749
750 netif_dbg(channel->efx, drv, channel->efx->net_dev,
751 "destroy chan %d\n", channel->channel);
752
753 efx_for_each_channel_rx_queue(rx_queue, channel)
754 efx_siena_remove_rx_queue(rx_queue);
755 efx_for_each_channel_tx_queue(tx_queue, channel)
756 efx_siena_remove_tx_queue(tx_queue);
757 efx_remove_eventq(channel);
758 channel->type->post_remove(channel);
759}
760
761void efx_siena_remove_channels(struct efx_nic *efx)
762{
763 struct efx_channel *channel;
764
765 efx_for_each_channel(channel, efx)
766 efx_siena_remove_channel(channel);
767
768 kfree(objp: efx->xdp_tx_queues);
769}
770
771static int efx_set_xdp_tx_queue(struct efx_nic *efx, int xdp_queue_number,
772 struct efx_tx_queue *tx_queue)
773{
774 if (xdp_queue_number >= efx->xdp_tx_queue_count)
775 return -EINVAL;
776
777 netif_dbg(efx, drv, efx->net_dev,
778 "Channel %u TXQ %u is XDP %u, HW %u\n",
779 tx_queue->channel->channel, tx_queue->label,
780 xdp_queue_number, tx_queue->queue);
781 efx->xdp_tx_queues[xdp_queue_number] = tx_queue;
782 return 0;
783}
784
785static void efx_set_xdp_channels(struct efx_nic *efx)
786{
787 struct efx_tx_queue *tx_queue;
788 struct efx_channel *channel;
789 unsigned int next_queue = 0;
790 int xdp_queue_number = 0;
791 int rc;
792
793 /* We need to mark which channels really have RX and TX
794 * queues, and adjust the TX queue numbers if we have separate
795 * RX-only and TX-only channels.
796 */
797 efx_for_each_channel(channel, efx) {
798 if (channel->channel < efx->tx_channel_offset)
799 continue;
800
801 if (efx_channel_is_xdp_tx(channel)) {
802 efx_for_each_channel_tx_queue(tx_queue, channel) {
803 tx_queue->queue = next_queue++;
804 rc = efx_set_xdp_tx_queue(efx, xdp_queue_number,
805 tx_queue);
806 if (rc == 0)
807 xdp_queue_number++;
808 }
809 } else {
810 efx_for_each_channel_tx_queue(tx_queue, channel) {
811 tx_queue->queue = next_queue++;
812 netif_dbg(efx, drv, efx->net_dev,
813 "Channel %u TXQ %u is HW %u\n",
814 channel->channel, tx_queue->label,
815 tx_queue->queue);
816 }
817
818 /* If XDP is borrowing queues from net stack, it must
819 * use the queue with no csum offload, which is the
820 * first one of the channel
821 * (note: tx_queue_by_type is not initialized yet)
822 */
823 if (efx->xdp_txq_queues_mode ==
824 EFX_XDP_TX_QUEUES_BORROWED) {
825 tx_queue = &channel->tx_queue[0];
826 rc = efx_set_xdp_tx_queue(efx, xdp_queue_number,
827 tx_queue);
828 if (rc == 0)
829 xdp_queue_number++;
830 }
831 }
832 }
833 WARN_ON(efx->xdp_txq_queues_mode == EFX_XDP_TX_QUEUES_DEDICATED &&
834 xdp_queue_number != efx->xdp_tx_queue_count);
835 WARN_ON(efx->xdp_txq_queues_mode != EFX_XDP_TX_QUEUES_DEDICATED &&
836 xdp_queue_number > efx->xdp_tx_queue_count);
837
838 /* If we have more CPUs than assigned XDP TX queues, assign the already
839 * existing queues to the exceeding CPUs
840 */
841 next_queue = 0;
842 while (xdp_queue_number < efx->xdp_tx_queue_count) {
843 tx_queue = efx->xdp_tx_queues[next_queue++];
844 rc = efx_set_xdp_tx_queue(efx, xdp_queue_number, tx_queue);
845 if (rc == 0)
846 xdp_queue_number++;
847 }
848}
849
850static int efx_soft_enable_interrupts(struct efx_nic *efx);
851static void efx_soft_disable_interrupts(struct efx_nic *efx);
852static void efx_init_napi_channel(struct efx_channel *channel);
853static void efx_fini_napi_channel(struct efx_channel *channel);
854
855int efx_siena_realloc_channels(struct efx_nic *efx, u32 rxq_entries,
856 u32 txq_entries)
857{
858 struct efx_channel *other_channel[EFX_MAX_CHANNELS], *channel;
859 unsigned int i, next_buffer_table = 0;
860 u32 old_rxq_entries, old_txq_entries;
861 int rc, rc2;
862
863 rc = efx_check_disabled(efx);
864 if (rc)
865 return rc;
866
867 /* Not all channels should be reallocated. We must avoid
868 * reallocating their buffer table entries.
869 */
870 efx_for_each_channel(channel, efx) {
871 struct efx_rx_queue *rx_queue;
872 struct efx_tx_queue *tx_queue;
873
874 if (channel->type->copy)
875 continue;
876 next_buffer_table = max(next_buffer_table,
877 channel->eventq.index +
878 channel->eventq.entries);
879 efx_for_each_channel_rx_queue(rx_queue, channel)
880 next_buffer_table = max(next_buffer_table,
881 rx_queue->rxd.index +
882 rx_queue->rxd.entries);
883 efx_for_each_channel_tx_queue(tx_queue, channel)
884 next_buffer_table = max(next_buffer_table,
885 tx_queue->txd.index +
886 tx_queue->txd.entries);
887 }
888
889 efx_device_detach_sync(efx);
890 efx_siena_stop_all(efx);
891 efx_soft_disable_interrupts(efx);
892
893 /* Clone channels (where possible) */
894 memset(other_channel, 0, sizeof(other_channel));
895 for (i = 0; i < efx->n_channels; i++) {
896 channel = efx->channel[i];
897 if (channel->type->copy)
898 channel = channel->type->copy(channel);
899 if (!channel) {
900 rc = -ENOMEM;
901 goto out;
902 }
903 other_channel[i] = channel;
904 }
905
906 /* Swap entry counts and channel pointers */
907 old_rxq_entries = efx->rxq_entries;
908 old_txq_entries = efx->txq_entries;
909 efx->rxq_entries = rxq_entries;
910 efx->txq_entries = txq_entries;
911 for (i = 0; i < efx->n_channels; i++)
912 swap(efx->channel[i], other_channel[i]);
913
914 /* Restart buffer table allocation */
915 efx->next_buffer_table = next_buffer_table;
916
917 for (i = 0; i < efx->n_channels; i++) {
918 channel = efx->channel[i];
919 if (!channel->type->copy)
920 continue;
921 rc = efx_probe_channel(channel);
922 if (rc)
923 goto rollback;
924 efx_init_napi_channel(channel: efx->channel[i]);
925 }
926
927 efx_set_xdp_channels(efx);
928out:
929 /* Destroy unused channel structures */
930 for (i = 0; i < efx->n_channels; i++) {
931 channel = other_channel[i];
932 if (channel && channel->type->copy) {
933 efx_fini_napi_channel(channel);
934 efx_siena_remove_channel(channel);
935 kfree(objp: channel);
936 }
937 }
938
939 rc2 = efx_soft_enable_interrupts(efx);
940 if (rc2) {
941 rc = rc ? rc : rc2;
942 netif_err(efx, drv, efx->net_dev,
943 "unable to restart interrupts on channel reallocation\n");
944 efx_siena_schedule_reset(efx, type: RESET_TYPE_DISABLE);
945 } else {
946 efx_siena_start_all(efx);
947 efx_device_attach_if_not_resetting(efx);
948 }
949 return rc;
950
951rollback:
952 /* Swap back */
953 efx->rxq_entries = old_rxq_entries;
954 efx->txq_entries = old_txq_entries;
955 for (i = 0; i < efx->n_channels; i++)
956 swap(efx->channel[i], other_channel[i]);
957 goto out;
958}
959
960int efx_siena_set_channels(struct efx_nic *efx)
961{
962 struct efx_channel *channel;
963 int rc;
964
965 if (efx->xdp_tx_queue_count) {
966 EFX_WARN_ON_PARANOID(efx->xdp_tx_queues);
967
968 /* Allocate array for XDP TX queue lookup. */
969 efx->xdp_tx_queues = kcalloc(n: efx->xdp_tx_queue_count,
970 size: sizeof(*efx->xdp_tx_queues),
971 GFP_KERNEL);
972 if (!efx->xdp_tx_queues)
973 return -ENOMEM;
974 }
975
976 efx_for_each_channel(channel, efx) {
977 if (channel->channel < efx->n_rx_channels)
978 channel->rx_queue.core_index = channel->channel;
979 else
980 channel->rx_queue.core_index = -1;
981 }
982
983 efx_set_xdp_channels(efx);
984
985 rc = netif_set_real_num_tx_queues(dev: efx->net_dev, txq: efx->n_tx_channels);
986 if (rc)
987 return rc;
988 return netif_set_real_num_rx_queues(dev: efx->net_dev, rxq: efx->n_rx_channels);
989}
990
991static bool efx_default_channel_want_txqs(struct efx_channel *channel)
992{
993 return channel->channel - channel->efx->tx_channel_offset <
994 channel->efx->n_tx_channels;
995}
996
997/*************
998 * START/STOP
999 *************/
1000
1001static int efx_soft_enable_interrupts(struct efx_nic *efx)
1002{
1003 struct efx_channel *channel, *end_channel;
1004 int rc;
1005
1006 BUG_ON(efx->state == STATE_DISABLED);
1007
1008 efx->irq_soft_enabled = true;
1009 smp_wmb();
1010
1011 efx_for_each_channel(channel, efx) {
1012 if (!channel->type->keep_eventq) {
1013 rc = efx_init_eventq(channel);
1014 if (rc)
1015 goto fail;
1016 }
1017 efx_siena_start_eventq(channel);
1018 }
1019
1020 efx_siena_mcdi_mode_event(efx);
1021
1022 return 0;
1023fail:
1024 end_channel = channel;
1025 efx_for_each_channel(channel, efx) {
1026 if (channel == end_channel)
1027 break;
1028 efx_siena_stop_eventq(channel);
1029 if (!channel->type->keep_eventq)
1030 efx_fini_eventq(channel);
1031 }
1032
1033 return rc;
1034}
1035
1036static void efx_soft_disable_interrupts(struct efx_nic *efx)
1037{
1038 struct efx_channel *channel;
1039
1040 if (efx->state == STATE_DISABLED)
1041 return;
1042
1043 efx_siena_mcdi_mode_poll(efx);
1044
1045 efx->irq_soft_enabled = false;
1046 smp_wmb();
1047
1048 if (efx->legacy_irq)
1049 synchronize_irq(irq: efx->legacy_irq);
1050
1051 efx_for_each_channel(channel, efx) {
1052 if (channel->irq)
1053 synchronize_irq(irq: channel->irq);
1054
1055 efx_siena_stop_eventq(channel);
1056 if (!channel->type->keep_eventq)
1057 efx_fini_eventq(channel);
1058 }
1059
1060 /* Flush the asynchronous MCDI request queue */
1061 efx_siena_mcdi_flush_async(efx);
1062}
1063
1064int efx_siena_enable_interrupts(struct efx_nic *efx)
1065{
1066 struct efx_channel *channel, *end_channel;
1067 int rc;
1068
1069 /* TODO: Is this really a bug? */
1070 BUG_ON(efx->state == STATE_DISABLED);
1071
1072 if (efx->eeh_disabled_legacy_irq) {
1073 enable_irq(irq: efx->legacy_irq);
1074 efx->eeh_disabled_legacy_irq = false;
1075 }
1076
1077 efx->type->irq_enable_master(efx);
1078
1079 efx_for_each_channel(channel, efx) {
1080 if (channel->type->keep_eventq) {
1081 rc = efx_init_eventq(channel);
1082 if (rc)
1083 goto fail;
1084 }
1085 }
1086
1087 rc = efx_soft_enable_interrupts(efx);
1088 if (rc)
1089 goto fail;
1090
1091 return 0;
1092
1093fail:
1094 end_channel = channel;
1095 efx_for_each_channel(channel, efx) {
1096 if (channel == end_channel)
1097 break;
1098 if (channel->type->keep_eventq)
1099 efx_fini_eventq(channel);
1100 }
1101
1102 efx->type->irq_disable_non_ev(efx);
1103
1104 return rc;
1105}
1106
1107void efx_siena_disable_interrupts(struct efx_nic *efx)
1108{
1109 struct efx_channel *channel;
1110
1111 efx_soft_disable_interrupts(efx);
1112
1113 efx_for_each_channel(channel, efx) {
1114 if (channel->type->keep_eventq)
1115 efx_fini_eventq(channel);
1116 }
1117
1118 efx->type->irq_disable_non_ev(efx);
1119}
1120
1121void efx_siena_start_channels(struct efx_nic *efx)
1122{
1123 struct efx_tx_queue *tx_queue;
1124 struct efx_rx_queue *rx_queue;
1125 struct efx_channel *channel;
1126
1127 efx_for_each_channel_rev(channel, efx) {
1128 efx_for_each_channel_tx_queue(tx_queue, channel) {
1129 efx_siena_init_tx_queue(tx_queue);
1130 atomic_inc(v: &efx->active_queues);
1131 }
1132
1133 efx_for_each_channel_rx_queue(rx_queue, channel) {
1134 efx_siena_init_rx_queue(rx_queue);
1135 atomic_inc(v: &efx->active_queues);
1136 efx_siena_stop_eventq(channel);
1137 efx_siena_fast_push_rx_descriptors(rx_queue, atomic: false);
1138 efx_siena_start_eventq(channel);
1139 }
1140
1141 WARN_ON(channel->rx_pkt_n_frags);
1142 }
1143}
1144
1145void efx_siena_stop_channels(struct efx_nic *efx)
1146{
1147 struct efx_tx_queue *tx_queue;
1148 struct efx_rx_queue *rx_queue;
1149 struct efx_channel *channel;
1150 int rc = 0;
1151
1152 /* Stop RX refill */
1153 efx_for_each_channel(channel, efx) {
1154 efx_for_each_channel_rx_queue(rx_queue, channel)
1155 rx_queue->refill_enabled = false;
1156 }
1157
1158 efx_for_each_channel(channel, efx) {
1159 /* RX packet processing is pipelined, so wait for the
1160 * NAPI handler to complete. At least event queue 0
1161 * might be kept active by non-data events, so don't
1162 * use napi_synchronize() but actually disable NAPI
1163 * temporarily.
1164 */
1165 if (efx_channel_has_rx_queue(channel)) {
1166 efx_siena_stop_eventq(channel);
1167 efx_siena_start_eventq(channel);
1168 }
1169 }
1170
1171 if (efx->type->fini_dmaq)
1172 rc = efx->type->fini_dmaq(efx);
1173
1174 if (rc) {
1175 netif_err(efx, drv, efx->net_dev, "failed to flush queues\n");
1176 } else {
1177 netif_dbg(efx, drv, efx->net_dev,
1178 "successfully flushed all queues\n");
1179 }
1180
1181 efx_for_each_channel(channel, efx) {
1182 efx_for_each_channel_rx_queue(rx_queue, channel)
1183 efx_siena_fini_rx_queue(rx_queue);
1184 efx_for_each_channel_tx_queue(tx_queue, channel)
1185 efx_siena_fini_tx_queue(tx_queue);
1186 }
1187}
1188
1189/**************************************************************************
1190 *
1191 * NAPI interface
1192 *
1193 *************************************************************************/
1194
1195/* Process channel's event queue
1196 *
1197 * This function is responsible for processing the event queue of a
1198 * single channel. The caller must guarantee that this function will
1199 * never be concurrently called more than once on the same channel,
1200 * though different channels may be being processed concurrently.
1201 */
1202static int efx_process_channel(struct efx_channel *channel, int budget)
1203{
1204 struct efx_tx_queue *tx_queue;
1205 struct list_head rx_list;
1206 int spent;
1207
1208 if (unlikely(!channel->enabled))
1209 return 0;
1210
1211 /* Prepare the batch receive list */
1212 EFX_WARN_ON_PARANOID(channel->rx_list != NULL);
1213 INIT_LIST_HEAD(list: &rx_list);
1214 channel->rx_list = &rx_list;
1215
1216 efx_for_each_channel_tx_queue(tx_queue, channel) {
1217 tx_queue->pkts_compl = 0;
1218 tx_queue->bytes_compl = 0;
1219 }
1220
1221 spent = efx_nic_process_eventq(channel, quota: budget);
1222 if (spent && efx_channel_has_rx_queue(channel)) {
1223 struct efx_rx_queue *rx_queue =
1224 efx_channel_get_rx_queue(channel);
1225
1226 efx_rx_flush_packet(channel);
1227 efx_siena_fast_push_rx_descriptors(rx_queue, atomic: true);
1228 }
1229
1230 /* Update BQL */
1231 efx_for_each_channel_tx_queue(tx_queue, channel) {
1232 if (tx_queue->bytes_compl) {
1233 netdev_tx_completed_queue(dev_queue: tx_queue->core_txq,
1234 pkts: tx_queue->pkts_compl,
1235 bytes: tx_queue->bytes_compl);
1236 }
1237 }
1238
1239 /* Receive any packets we queued up */
1240 netif_receive_skb_list(head: channel->rx_list);
1241 channel->rx_list = NULL;
1242
1243 return spent;
1244}
1245
1246static void efx_update_irq_mod(struct efx_nic *efx, struct efx_channel *channel)
1247{
1248 int step = efx->irq_mod_step_us;
1249
1250 if (channel->irq_mod_score < irq_adapt_low_thresh) {
1251 if (channel->irq_moderation_us > step) {
1252 channel->irq_moderation_us -= step;
1253 efx->type->push_irq_moderation(channel);
1254 }
1255 } else if (channel->irq_mod_score > irq_adapt_high_thresh) {
1256 if (channel->irq_moderation_us <
1257 efx->irq_rx_moderation_us) {
1258 channel->irq_moderation_us += step;
1259 efx->type->push_irq_moderation(channel);
1260 }
1261 }
1262
1263 channel->irq_count = 0;
1264 channel->irq_mod_score = 0;
1265}
1266
1267/* NAPI poll handler
1268 *
1269 * NAPI guarantees serialisation of polls of the same device, which
1270 * provides the guarantee required by efx_process_channel().
1271 */
1272static int efx_poll(struct napi_struct *napi, int budget)
1273{
1274 struct efx_channel *channel =
1275 container_of(napi, struct efx_channel, napi_str);
1276 struct efx_nic *efx = channel->efx;
1277#ifdef CONFIG_RFS_ACCEL
1278 unsigned int time;
1279#endif
1280 int spent;
1281
1282 netif_vdbg(efx, intr, efx->net_dev,
1283 "channel %d NAPI poll executing on CPU %d\n",
1284 channel->channel, raw_smp_processor_id());
1285
1286 spent = efx_process_channel(channel, budget);
1287
1288 xdp_do_flush();
1289
1290 if (spent < budget) {
1291 if (efx_channel_has_rx_queue(channel) &&
1292 efx->irq_rx_adaptive &&
1293 unlikely(++channel->irq_count == 1000)) {
1294 efx_update_irq_mod(efx, channel);
1295 }
1296
1297#ifdef CONFIG_RFS_ACCEL
1298 /* Perhaps expire some ARFS filters */
1299 time = jiffies - channel->rfs_last_expiry;
1300 /* Would our quota be >= 20? */
1301 if (channel->rfs_filter_count * time >= 600 * HZ)
1302 mod_delayed_work(wq: system_wq, dwork: &channel->filter_work, delay: 0);
1303#endif
1304
1305 /* There is no race here; although napi_disable() will
1306 * only wait for napi_complete(), this isn't a problem
1307 * since efx_nic_eventq_read_ack() will have no effect if
1308 * interrupts have already been disabled.
1309 */
1310 if (napi_complete_done(n: napi, work_done: spent))
1311 efx_nic_eventq_read_ack(channel);
1312 }
1313
1314 return spent;
1315}
1316
1317static void efx_init_napi_channel(struct efx_channel *channel)
1318{
1319 struct efx_nic *efx = channel->efx;
1320
1321 channel->napi_dev = efx->net_dev;
1322 netif_napi_add(dev: channel->napi_dev, napi: &channel->napi_str, poll: efx_poll);
1323}
1324
1325void efx_siena_init_napi(struct efx_nic *efx)
1326{
1327 struct efx_channel *channel;
1328
1329 efx_for_each_channel(channel, efx)
1330 efx_init_napi_channel(channel);
1331}
1332
1333static void efx_fini_napi_channel(struct efx_channel *channel)
1334{
1335 if (channel->napi_dev)
1336 netif_napi_del(napi: &channel->napi_str);
1337
1338 channel->napi_dev = NULL;
1339}
1340
1341void efx_siena_fini_napi(struct efx_nic *efx)
1342{
1343 struct efx_channel *channel;
1344
1345 efx_for_each_channel(channel, efx)
1346 efx_fini_napi_channel(channel);
1347}
1348
1349/***************
1350 * Housekeeping
1351 ***************/
1352
1353static int efx_channel_dummy_op_int(struct efx_channel *channel)
1354{
1355 return 0;
1356}
1357
1358void efx_siena_channel_dummy_op_void(struct efx_channel *channel)
1359{
1360}
1361
1362static const struct efx_channel_type efx_default_channel_type = {
1363 .pre_probe = efx_channel_dummy_op_int,
1364 .post_remove = efx_siena_channel_dummy_op_void,
1365 .get_name = efx_get_channel_name,
1366 .copy = efx_copy_channel,
1367 .want_txqs = efx_default_channel_want_txqs,
1368 .keep_eventq = false,
1369 .want_pio = true,
1370};
1371

source code of linux/drivers/net/ethernet/sfc/siena/efx_channels.c