Merge tag 'please-pull-fix-ia64-warnings' of git://git.kernel.org/pub/scm/linux/kerne...
[cascardo/linux.git] / drivers / net / team / team_mode_loadbalance.c
1 /*
2  * drivers/net/team/team_mode_loadbalance.c - Load-balancing mode for team
3  * Copyright (c) 2012 Jiri Pirko <jpirko@redhat.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  */
10
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/errno.h>
16 #include <linux/netdevice.h>
17 #include <linux/filter.h>
18 #include <linux/if_team.h>
19
20 struct lb_priv;
21
22 typedef struct team_port *lb_select_tx_port_func_t(struct team *,
23                                                    struct lb_priv *,
24                                                    struct sk_buff *,
25                                                    unsigned char);
26
27 #define LB_TX_HASHTABLE_SIZE 256 /* hash is a char */
28
29 struct lb_stats {
30         u64 tx_bytes;
31 };
32
33 struct lb_pcpu_stats {
34         struct lb_stats hash_stats[LB_TX_HASHTABLE_SIZE];
35         struct u64_stats_sync syncp;
36 };
37
38 struct lb_stats_info {
39         struct lb_stats stats;
40         struct lb_stats last_stats;
41         struct team_option_inst_info *opt_inst_info;
42 };
43
44 struct lb_port_mapping {
45         struct team_port __rcu *port;
46         struct team_option_inst_info *opt_inst_info;
47 };
48
49 struct lb_priv_ex {
50         struct team *team;
51         struct lb_port_mapping tx_hash_to_port_mapping[LB_TX_HASHTABLE_SIZE];
52         struct sock_fprog *orig_fprog;
53         struct {
54                 unsigned int refresh_interval; /* in tenths of second */
55                 struct delayed_work refresh_dw;
56                 struct lb_stats_info info[LB_TX_HASHTABLE_SIZE];
57         } stats;
58 };
59
60 struct lb_priv {
61         struct sk_filter __rcu *fp;
62         lb_select_tx_port_func_t __rcu *select_tx_port_func;
63         struct lb_pcpu_stats __percpu *pcpu_stats;
64         struct lb_priv_ex *ex; /* priv extension */
65 };
66
67 static struct lb_priv *get_lb_priv(struct team *team)
68 {
69         return (struct lb_priv *) &team->mode_priv;
70 }
71
72 struct lb_port_priv {
73         struct lb_stats __percpu *pcpu_stats;
74         struct lb_stats_info stats_info;
75 };
76
77 static struct lb_port_priv *get_lb_port_priv(struct team_port *port)
78 {
79         return (struct lb_port_priv *) &port->mode_priv;
80 }
81
82 #define LB_HTPM_PORT_BY_HASH(lp_priv, hash) \
83         (lb_priv)->ex->tx_hash_to_port_mapping[hash].port
84
85 #define LB_HTPM_OPT_INST_INFO_BY_HASH(lp_priv, hash) \
86         (lb_priv)->ex->tx_hash_to_port_mapping[hash].opt_inst_info
87
88 static void lb_tx_hash_to_port_mapping_null_port(struct team *team,
89                                                  struct team_port *port)
90 {
91         struct lb_priv *lb_priv = get_lb_priv(team);
92         bool changed = false;
93         int i;
94
95         for (i = 0; i < LB_TX_HASHTABLE_SIZE; i++) {
96                 struct lb_port_mapping *pm;
97
98                 pm = &lb_priv->ex->tx_hash_to_port_mapping[i];
99                 if (rcu_access_pointer(pm->port) == port) {
100                         RCU_INIT_POINTER(pm->port, NULL);
101                         team_option_inst_set_change(pm->opt_inst_info);
102                         changed = true;
103                 }
104         }
105         if (changed)
106                 team_options_change_check(team);
107 }
108
109 /* Basic tx selection based solely by hash */
110 static struct team_port *lb_hash_select_tx_port(struct team *team,
111                                                 struct lb_priv *lb_priv,
112                                                 struct sk_buff *skb,
113                                                 unsigned char hash)
114 {
115         int port_index = team_num_to_port_index(team, hash);
116
117         return team_get_port_by_index_rcu(team, port_index);
118 }
119
120 /* Hash to port mapping select tx port */
121 static struct team_port *lb_htpm_select_tx_port(struct team *team,
122                                                 struct lb_priv *lb_priv,
123                                                 struct sk_buff *skb,
124                                                 unsigned char hash)
125 {
126         return rcu_dereference_bh(LB_HTPM_PORT_BY_HASH(lb_priv, hash));
127 }
128
129 struct lb_select_tx_port {
130         char *name;
131         lb_select_tx_port_func_t *func;
132 };
133
134 static const struct lb_select_tx_port lb_select_tx_port_list[] = {
135         {
136                 .name = "hash",
137                 .func = lb_hash_select_tx_port,
138         },
139         {
140                 .name = "hash_to_port_mapping",
141                 .func = lb_htpm_select_tx_port,
142         },
143 };
144 #define LB_SELECT_TX_PORT_LIST_COUNT ARRAY_SIZE(lb_select_tx_port_list)
145
146 static char *lb_select_tx_port_get_name(lb_select_tx_port_func_t *func)
147 {
148         int i;
149
150         for (i = 0; i < LB_SELECT_TX_PORT_LIST_COUNT; i++) {
151                 const struct lb_select_tx_port *item;
152
153                 item = &lb_select_tx_port_list[i];
154                 if (item->func == func)
155                         return item->name;
156         }
157         return NULL;
158 }
159
160 static lb_select_tx_port_func_t *lb_select_tx_port_get_func(const char *name)
161 {
162         int i;
163
164         for (i = 0; i < LB_SELECT_TX_PORT_LIST_COUNT; i++) {
165                 const struct lb_select_tx_port *item;
166
167                 item = &lb_select_tx_port_list[i];
168                 if (!strcmp(item->name, name))
169                         return item->func;
170         }
171         return NULL;
172 }
173
174 static unsigned int lb_get_skb_hash(struct lb_priv *lb_priv,
175                                     struct sk_buff *skb)
176 {
177         struct sk_filter *fp;
178         uint32_t lhash;
179         unsigned char *c;
180
181         fp = rcu_dereference_bh(lb_priv->fp);
182         if (unlikely(!fp))
183                 return 0;
184         lhash = SK_RUN_FILTER(fp, skb);
185         c = (char *) &lhash;
186         return c[0] ^ c[1] ^ c[2] ^ c[3];
187 }
188
189 static void lb_update_tx_stats(unsigned int tx_bytes, struct lb_priv *lb_priv,
190                                struct lb_port_priv *lb_port_priv,
191                                unsigned char hash)
192 {
193         struct lb_pcpu_stats *pcpu_stats;
194         struct lb_stats *port_stats;
195         struct lb_stats *hash_stats;
196
197         pcpu_stats = this_cpu_ptr(lb_priv->pcpu_stats);
198         port_stats = this_cpu_ptr(lb_port_priv->pcpu_stats);
199         hash_stats = &pcpu_stats->hash_stats[hash];
200         u64_stats_update_begin(&pcpu_stats->syncp);
201         port_stats->tx_bytes += tx_bytes;
202         hash_stats->tx_bytes += tx_bytes;
203         u64_stats_update_end(&pcpu_stats->syncp);
204 }
205
206 static bool lb_transmit(struct team *team, struct sk_buff *skb)
207 {
208         struct lb_priv *lb_priv = get_lb_priv(team);
209         lb_select_tx_port_func_t *select_tx_port_func;
210         struct team_port *port;
211         unsigned char hash;
212         unsigned int tx_bytes = skb->len;
213
214         hash = lb_get_skb_hash(lb_priv, skb);
215         select_tx_port_func = rcu_dereference_bh(lb_priv->select_tx_port_func);
216         port = select_tx_port_func(team, lb_priv, skb, hash);
217         if (unlikely(!port))
218                 goto drop;
219         if (team_dev_queue_xmit(team, port, skb))
220                 return false;
221         lb_update_tx_stats(tx_bytes, lb_priv, get_lb_port_priv(port), hash);
222         return true;
223
224 drop:
225         dev_kfree_skb_any(skb);
226         return false;
227 }
228
229 static int lb_bpf_func_get(struct team *team, struct team_gsetter_ctx *ctx)
230 {
231         struct lb_priv *lb_priv = get_lb_priv(team);
232
233         if (!lb_priv->ex->orig_fprog) {
234                 ctx->data.bin_val.len = 0;
235                 ctx->data.bin_val.ptr = NULL;
236                 return 0;
237         }
238         ctx->data.bin_val.len = lb_priv->ex->orig_fprog->len *
239                                 sizeof(struct sock_filter);
240         ctx->data.bin_val.ptr = lb_priv->ex->orig_fprog->filter;
241         return 0;
242 }
243
244 static int __fprog_create(struct sock_fprog **pfprog, u32 data_len,
245                           const void *data)
246 {
247         struct sock_fprog *fprog;
248         struct sock_filter *filter = (struct sock_filter *) data;
249
250         if (data_len % sizeof(struct sock_filter))
251                 return -EINVAL;
252         fprog = kmalloc(sizeof(struct sock_fprog), GFP_KERNEL);
253         if (!fprog)
254                 return -ENOMEM;
255         fprog->filter = kmemdup(filter, data_len, GFP_KERNEL);
256         if (!fprog->filter) {
257                 kfree(fprog);
258                 return -ENOMEM;
259         }
260         fprog->len = data_len / sizeof(struct sock_filter);
261         *pfprog = fprog;
262         return 0;
263 }
264
265 static void __fprog_destroy(struct sock_fprog *fprog)
266 {
267         kfree(fprog->filter);
268         kfree(fprog);
269 }
270
271 static int lb_bpf_func_set(struct team *team, struct team_gsetter_ctx *ctx)
272 {
273         struct lb_priv *lb_priv = get_lb_priv(team);
274         struct sk_filter *fp = NULL;
275         struct sk_filter *orig_fp;
276         struct sock_fprog *fprog = NULL;
277         int err;
278
279         if (ctx->data.bin_val.len) {
280                 err = __fprog_create(&fprog, ctx->data.bin_val.len,
281                                      ctx->data.bin_val.ptr);
282                 if (err)
283                         return err;
284                 err = sk_unattached_filter_create(&fp, fprog);
285                 if (err) {
286                         __fprog_destroy(fprog);
287                         return err;
288                 }
289         }
290
291         if (lb_priv->ex->orig_fprog) {
292                 /* Clear old filter data */
293                 __fprog_destroy(lb_priv->ex->orig_fprog);
294                 orig_fp = rcu_dereference_protected(lb_priv->fp,
295                                                 lockdep_is_held(&team->lock));
296                 sk_unattached_filter_destroy(orig_fp);
297         }
298
299         rcu_assign_pointer(lb_priv->fp, fp);
300         lb_priv->ex->orig_fprog = fprog;
301         return 0;
302 }
303
304 static int lb_tx_method_get(struct team *team, struct team_gsetter_ctx *ctx)
305 {
306         struct lb_priv *lb_priv = get_lb_priv(team);
307         lb_select_tx_port_func_t *func;
308         char *name;
309
310         func = rcu_dereference_protected(lb_priv->select_tx_port_func,
311                                          lockdep_is_held(&team->lock));
312         name = lb_select_tx_port_get_name(func);
313         BUG_ON(!name);
314         ctx->data.str_val = name;
315         return 0;
316 }
317
318 static int lb_tx_method_set(struct team *team, struct team_gsetter_ctx *ctx)
319 {
320         struct lb_priv *lb_priv = get_lb_priv(team);
321         lb_select_tx_port_func_t *func;
322
323         func = lb_select_tx_port_get_func(ctx->data.str_val);
324         if (!func)
325                 return -EINVAL;
326         rcu_assign_pointer(lb_priv->select_tx_port_func, func);
327         return 0;
328 }
329
330 static int lb_tx_hash_to_port_mapping_init(struct team *team,
331                                            struct team_option_inst_info *info)
332 {
333         struct lb_priv *lb_priv = get_lb_priv(team);
334         unsigned char hash = info->array_index;
335
336         LB_HTPM_OPT_INST_INFO_BY_HASH(lb_priv, hash) = info;
337         return 0;
338 }
339
340 static int lb_tx_hash_to_port_mapping_get(struct team *team,
341                                           struct team_gsetter_ctx *ctx)
342 {
343         struct lb_priv *lb_priv = get_lb_priv(team);
344         struct team_port *port;
345         unsigned char hash = ctx->info->array_index;
346
347         port = LB_HTPM_PORT_BY_HASH(lb_priv, hash);
348         ctx->data.u32_val = port ? port->dev->ifindex : 0;
349         return 0;
350 }
351
352 static int lb_tx_hash_to_port_mapping_set(struct team *team,
353                                           struct team_gsetter_ctx *ctx)
354 {
355         struct lb_priv *lb_priv = get_lb_priv(team);
356         struct team_port *port;
357         unsigned char hash = ctx->info->array_index;
358
359         list_for_each_entry(port, &team->port_list, list) {
360                 if (ctx->data.u32_val == port->dev->ifindex &&
361                     team_port_enabled(port)) {
362                         rcu_assign_pointer(LB_HTPM_PORT_BY_HASH(lb_priv, hash),
363                                            port);
364                         return 0;
365                 }
366         }
367         return -ENODEV;
368 }
369
370 static int lb_hash_stats_init(struct team *team,
371                               struct team_option_inst_info *info)
372 {
373         struct lb_priv *lb_priv = get_lb_priv(team);
374         unsigned char hash = info->array_index;
375
376         lb_priv->ex->stats.info[hash].opt_inst_info = info;
377         return 0;
378 }
379
380 static int lb_hash_stats_get(struct team *team, struct team_gsetter_ctx *ctx)
381 {
382         struct lb_priv *lb_priv = get_lb_priv(team);
383         unsigned char hash = ctx->info->array_index;
384
385         ctx->data.bin_val.ptr = &lb_priv->ex->stats.info[hash].stats;
386         ctx->data.bin_val.len = sizeof(struct lb_stats);
387         return 0;
388 }
389
390 static int lb_port_stats_init(struct team *team,
391                               struct team_option_inst_info *info)
392 {
393         struct team_port *port = info->port;
394         struct lb_port_priv *lb_port_priv = get_lb_port_priv(port);
395
396         lb_port_priv->stats_info.opt_inst_info = info;
397         return 0;
398 }
399
400 static int lb_port_stats_get(struct team *team, struct team_gsetter_ctx *ctx)
401 {
402         struct team_port *port = ctx->info->port;
403         struct lb_port_priv *lb_port_priv = get_lb_port_priv(port);
404
405         ctx->data.bin_val.ptr = &lb_port_priv->stats_info.stats;
406         ctx->data.bin_val.len = sizeof(struct lb_stats);
407         return 0;
408 }
409
410 static void __lb_stats_info_refresh_prepare(struct lb_stats_info *s_info)
411 {
412         memcpy(&s_info->last_stats, &s_info->stats, sizeof(struct lb_stats));
413         memset(&s_info->stats, 0, sizeof(struct lb_stats));
414 }
415
416 static bool __lb_stats_info_refresh_check(struct lb_stats_info *s_info,
417                                           struct team *team)
418 {
419         if (memcmp(&s_info->last_stats, &s_info->stats,
420             sizeof(struct lb_stats))) {
421                 team_option_inst_set_change(s_info->opt_inst_info);
422                 return true;
423         }
424         return false;
425 }
426
427 static void __lb_one_cpu_stats_add(struct lb_stats *acc_stats,
428                                    struct lb_stats *cpu_stats,
429                                    struct u64_stats_sync *syncp)
430 {
431         unsigned int start;
432         struct lb_stats tmp;
433
434         do {
435                 start = u64_stats_fetch_begin_bh(syncp);
436                 tmp.tx_bytes = cpu_stats->tx_bytes;
437         } while (u64_stats_fetch_retry_bh(syncp, start));
438         acc_stats->tx_bytes += tmp.tx_bytes;
439 }
440
441 static void lb_stats_refresh(struct work_struct *work)
442 {
443         struct team *team;
444         struct lb_priv *lb_priv;
445         struct lb_priv_ex *lb_priv_ex;
446         struct lb_pcpu_stats *pcpu_stats;
447         struct lb_stats *stats;
448         struct lb_stats_info *s_info;
449         struct team_port *port;
450         bool changed = false;
451         int i;
452         int j;
453
454         lb_priv_ex = container_of(work, struct lb_priv_ex,
455                                   stats.refresh_dw.work);
456
457         team = lb_priv_ex->team;
458         lb_priv = get_lb_priv(team);
459
460         if (!mutex_trylock(&team->lock)) {
461                 schedule_delayed_work(&lb_priv_ex->stats.refresh_dw, 0);
462                 return;
463         }
464
465         for (j = 0; j < LB_TX_HASHTABLE_SIZE; j++) {
466                 s_info = &lb_priv->ex->stats.info[j];
467                 __lb_stats_info_refresh_prepare(s_info);
468                 for_each_possible_cpu(i) {
469                         pcpu_stats = per_cpu_ptr(lb_priv->pcpu_stats, i);
470                         stats = &pcpu_stats->hash_stats[j];
471                         __lb_one_cpu_stats_add(&s_info->stats, stats,
472                                                &pcpu_stats->syncp);
473                 }
474                 changed |= __lb_stats_info_refresh_check(s_info, team);
475         }
476
477         list_for_each_entry(port, &team->port_list, list) {
478                 struct lb_port_priv *lb_port_priv = get_lb_port_priv(port);
479
480                 s_info = &lb_port_priv->stats_info;
481                 __lb_stats_info_refresh_prepare(s_info);
482                 for_each_possible_cpu(i) {
483                         pcpu_stats = per_cpu_ptr(lb_priv->pcpu_stats, i);
484                         stats = per_cpu_ptr(lb_port_priv->pcpu_stats, i);
485                         __lb_one_cpu_stats_add(&s_info->stats, stats,
486                                                &pcpu_stats->syncp);
487                 }
488                 changed |= __lb_stats_info_refresh_check(s_info, team);
489         }
490
491         if (changed)
492                 team_options_change_check(team);
493
494         schedule_delayed_work(&lb_priv_ex->stats.refresh_dw,
495                               (lb_priv_ex->stats.refresh_interval * HZ) / 10);
496
497         mutex_unlock(&team->lock);
498 }
499
500 static int lb_stats_refresh_interval_get(struct team *team,
501                                          struct team_gsetter_ctx *ctx)
502 {
503         struct lb_priv *lb_priv = get_lb_priv(team);
504
505         ctx->data.u32_val = lb_priv->ex->stats.refresh_interval;
506         return 0;
507 }
508
509 static int lb_stats_refresh_interval_set(struct team *team,
510                                          struct team_gsetter_ctx *ctx)
511 {
512         struct lb_priv *lb_priv = get_lb_priv(team);
513         unsigned int interval;
514
515         interval = ctx->data.u32_val;
516         if (lb_priv->ex->stats.refresh_interval == interval)
517                 return 0;
518         lb_priv->ex->stats.refresh_interval = interval;
519         if (interval)
520                 schedule_delayed_work(&lb_priv->ex->stats.refresh_dw, 0);
521         else
522                 cancel_delayed_work(&lb_priv->ex->stats.refresh_dw);
523         return 0;
524 }
525
526 static const struct team_option lb_options[] = {
527         {
528                 .name = "bpf_hash_func",
529                 .type = TEAM_OPTION_TYPE_BINARY,
530                 .getter = lb_bpf_func_get,
531                 .setter = lb_bpf_func_set,
532         },
533         {
534                 .name = "lb_tx_method",
535                 .type = TEAM_OPTION_TYPE_STRING,
536                 .getter = lb_tx_method_get,
537                 .setter = lb_tx_method_set,
538         },
539         {
540                 .name = "lb_tx_hash_to_port_mapping",
541                 .array_size = LB_TX_HASHTABLE_SIZE,
542                 .type = TEAM_OPTION_TYPE_U32,
543                 .init = lb_tx_hash_to_port_mapping_init,
544                 .getter = lb_tx_hash_to_port_mapping_get,
545                 .setter = lb_tx_hash_to_port_mapping_set,
546         },
547         {
548                 .name = "lb_hash_stats",
549                 .array_size = LB_TX_HASHTABLE_SIZE,
550                 .type = TEAM_OPTION_TYPE_BINARY,
551                 .init = lb_hash_stats_init,
552                 .getter = lb_hash_stats_get,
553         },
554         {
555                 .name = "lb_port_stats",
556                 .per_port = true,
557                 .type = TEAM_OPTION_TYPE_BINARY,
558                 .init = lb_port_stats_init,
559                 .getter = lb_port_stats_get,
560         },
561         {
562                 .name = "lb_stats_refresh_interval",
563                 .type = TEAM_OPTION_TYPE_U32,
564                 .getter = lb_stats_refresh_interval_get,
565                 .setter = lb_stats_refresh_interval_set,
566         },
567 };
568
569 static int lb_init(struct team *team)
570 {
571         struct lb_priv *lb_priv = get_lb_priv(team);
572         lb_select_tx_port_func_t *func;
573         int err;
574
575         /* set default tx port selector */
576         func = lb_select_tx_port_get_func("hash");
577         BUG_ON(!func);
578         rcu_assign_pointer(lb_priv->select_tx_port_func, func);
579
580         lb_priv->ex = kzalloc(sizeof(*lb_priv->ex), GFP_KERNEL);
581         if (!lb_priv->ex)
582                 return -ENOMEM;
583         lb_priv->ex->team = team;
584
585         lb_priv->pcpu_stats = alloc_percpu(struct lb_pcpu_stats);
586         if (!lb_priv->pcpu_stats) {
587                 err = -ENOMEM;
588                 goto err_alloc_pcpu_stats;
589         }
590
591         INIT_DELAYED_WORK(&lb_priv->ex->stats.refresh_dw, lb_stats_refresh);
592
593         err = team_options_register(team, lb_options, ARRAY_SIZE(lb_options));
594         if (err)
595                 goto err_options_register;
596         return 0;
597
598 err_options_register:
599         free_percpu(lb_priv->pcpu_stats);
600 err_alloc_pcpu_stats:
601         kfree(lb_priv->ex);
602         return err;
603 }
604
605 static void lb_exit(struct team *team)
606 {
607         struct lb_priv *lb_priv = get_lb_priv(team);
608
609         team_options_unregister(team, lb_options,
610                                 ARRAY_SIZE(lb_options));
611         cancel_delayed_work_sync(&lb_priv->ex->stats.refresh_dw);
612         free_percpu(lb_priv->pcpu_stats);
613         kfree(lb_priv->ex);
614 }
615
616 static int lb_port_enter(struct team *team, struct team_port *port)
617 {
618         struct lb_port_priv *lb_port_priv = get_lb_port_priv(port);
619
620         lb_port_priv->pcpu_stats = alloc_percpu(struct lb_stats);
621         if (!lb_port_priv->pcpu_stats)
622                 return -ENOMEM;
623         return 0;
624 }
625
626 static void lb_port_leave(struct team *team, struct team_port *port)
627 {
628         struct lb_port_priv *lb_port_priv = get_lb_port_priv(port);
629
630         free_percpu(lb_port_priv->pcpu_stats);
631 }
632
633 static void lb_port_disabled(struct team *team, struct team_port *port)
634 {
635         lb_tx_hash_to_port_mapping_null_port(team, port);
636 }
637
638 static const struct team_mode_ops lb_mode_ops = {
639         .init                   = lb_init,
640         .exit                   = lb_exit,
641         .port_enter             = lb_port_enter,
642         .port_leave             = lb_port_leave,
643         .port_disabled          = lb_port_disabled,
644         .transmit               = lb_transmit,
645 };
646
647 static const struct team_mode lb_mode = {
648         .kind           = "loadbalance",
649         .owner          = THIS_MODULE,
650         .priv_size      = sizeof(struct lb_priv),
651         .port_priv_size = sizeof(struct lb_port_priv),
652         .ops            = &lb_mode_ops,
653 };
654
655 static int __init lb_init_module(void)
656 {
657         return team_mode_register(&lb_mode);
658 }
659
660 static void __exit lb_cleanup_module(void)
661 {
662         team_mode_unregister(&lb_mode);
663 }
664
665 module_init(lb_init_module);
666 module_exit(lb_cleanup_module);
667
668 MODULE_LICENSE("GPL v2");
669 MODULE_AUTHOR("Jiri Pirko <jpirko@redhat.com>");
670 MODULE_DESCRIPTION("Load-balancing mode for team");
671 MODULE_ALIAS("team-mode-loadbalance");