scsi: ufs: fix race between clock gating and devfreq scaling work
[linux/fpc-iii.git] / net / core / gen_stats.c
blob18f17e1e5762538c7ed41832ea4eba7b65beac15
1 /*
2 * net/core/gen_stats.c
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Thomas Graf <tgraf@suug.ch>
10 * Jamal Hadi Salim
11 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
13 * See Documentation/networking/gen_stats.txt
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/interrupt.h>
20 #include <linux/socket.h>
21 #include <linux/rtnetlink.h>
22 #include <linux/gen_stats.h>
23 #include <net/netlink.h>
24 #include <net/gen_stats.h>
27 static inline int
28 gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size, int padattr)
30 if (nla_put_64bit(d->skb, type, size, buf, padattr))
31 goto nla_put_failure;
32 return 0;
34 nla_put_failure:
35 if (d->lock)
36 spin_unlock_bh(d->lock);
37 kfree(d->xstats);
38 d->xstats = NULL;
39 d->xstats_len = 0;
40 return -1;
43 /**
44 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
45 * @skb: socket buffer to put statistics TLVs into
46 * @type: TLV type for top level statistic TLV
47 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
48 * @xstats_type: TLV type for backward compatibility xstats TLV
49 * @lock: statistics lock
50 * @d: dumping handle
51 * @padattr: padding attribute
53 * Initializes the dumping handle, grabs the statistic lock and appends
54 * an empty TLV header to the socket buffer for use a container for all
55 * other statistic TLVS.
57 * The dumping handle is marked to be in backward compatibility mode telling
58 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
60 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
62 int
63 gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
64 int xstats_type, spinlock_t *lock,
65 struct gnet_dump *d, int padattr)
66 __acquires(lock)
68 memset(d, 0, sizeof(*d));
70 if (type)
71 d->tail = (struct nlattr *)skb_tail_pointer(skb);
72 d->skb = skb;
73 d->compat_tc_stats = tc_stats_type;
74 d->compat_xstats = xstats_type;
75 d->padattr = padattr;
76 if (lock) {
77 d->lock = lock;
78 spin_lock_bh(lock);
80 if (d->tail) {
81 int ret = gnet_stats_copy(d, type, NULL, 0, padattr);
83 /* The initial attribute added in gnet_stats_copy() may be
84 * preceded by a padding attribute, in which case d->tail will
85 * end up pointing at the padding instead of the real attribute.
86 * Fix this so gnet_stats_finish_copy() adjusts the length of
87 * the right attribute.
89 if (ret == 0 && d->tail->nla_type == padattr)
90 d->tail = (struct nlattr *)((char *)d->tail +
91 NLA_ALIGN(d->tail->nla_len));
92 return ret;
95 return 0;
97 EXPORT_SYMBOL(gnet_stats_start_copy_compat);
99 /**
100 * gnet_stats_start_copy - start dumping procedure in compatibility mode
101 * @skb: socket buffer to put statistics TLVs into
102 * @type: TLV type for top level statistic TLV
103 * @lock: statistics lock
104 * @d: dumping handle
105 * @padattr: padding attribute
107 * Initializes the dumping handle, grabs the statistic lock and appends
108 * an empty TLV header to the socket buffer for use a container for all
109 * other statistic TLVS.
111 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
114 gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
115 struct gnet_dump *d, int padattr)
117 return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d, padattr);
119 EXPORT_SYMBOL(gnet_stats_start_copy);
121 static void
122 __gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
123 struct gnet_stats_basic_cpu __percpu *cpu)
125 int i;
127 for_each_possible_cpu(i) {
128 struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i);
129 unsigned int start;
130 u64 bytes;
131 u32 packets;
133 do {
134 start = u64_stats_fetch_begin_irq(&bcpu->syncp);
135 bytes = bcpu->bstats.bytes;
136 packets = bcpu->bstats.packets;
137 } while (u64_stats_fetch_retry_irq(&bcpu->syncp, start));
139 bstats->bytes += bytes;
140 bstats->packets += packets;
144 void
145 __gnet_stats_copy_basic(const seqcount_t *running,
146 struct gnet_stats_basic_packed *bstats,
147 struct gnet_stats_basic_cpu __percpu *cpu,
148 struct gnet_stats_basic_packed *b)
150 unsigned int seq;
152 if (cpu) {
153 __gnet_stats_copy_basic_cpu(bstats, cpu);
154 return;
156 do {
157 if (running)
158 seq = read_seqcount_begin(running);
159 bstats->bytes = b->bytes;
160 bstats->packets = b->packets;
161 } while (running && read_seqcount_retry(running, seq));
163 EXPORT_SYMBOL(__gnet_stats_copy_basic);
166 * gnet_stats_copy_basic - copy basic statistics into statistic TLV
167 * @running: seqcount_t pointer
168 * @d: dumping handle
169 * @cpu: copy statistic per cpu
170 * @b: basic statistics
172 * Appends the basic statistics to the top level TLV created by
173 * gnet_stats_start_copy().
175 * Returns 0 on success or -1 with the statistic lock released
176 * if the room in the socket buffer was not sufficient.
179 gnet_stats_copy_basic(const seqcount_t *running,
180 struct gnet_dump *d,
181 struct gnet_stats_basic_cpu __percpu *cpu,
182 struct gnet_stats_basic_packed *b)
184 struct gnet_stats_basic_packed bstats = {0};
186 __gnet_stats_copy_basic(running, &bstats, cpu, b);
188 if (d->compat_tc_stats) {
189 d->tc_stats.bytes = bstats.bytes;
190 d->tc_stats.packets = bstats.packets;
193 if (d->tail) {
194 struct gnet_stats_basic sb;
196 memset(&sb, 0, sizeof(sb));
197 sb.bytes = bstats.bytes;
198 sb.packets = bstats.packets;
199 return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb),
200 TCA_STATS_PAD);
202 return 0;
204 EXPORT_SYMBOL(gnet_stats_copy_basic);
207 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
208 * @d: dumping handle
209 * @b: basic statistics
210 * @r: rate estimator statistics
212 * Appends the rate estimator statistics to the top level TLV created by
213 * gnet_stats_start_copy().
215 * Returns 0 on success or -1 with the statistic lock released
216 * if the room in the socket buffer was not sufficient.
219 gnet_stats_copy_rate_est(struct gnet_dump *d,
220 const struct gnet_stats_basic_packed *b,
221 struct gnet_stats_rate_est64 *r)
223 struct gnet_stats_rate_est est;
224 int res;
226 if (b && !gen_estimator_active(b, r))
227 return 0;
229 est.bps = min_t(u64, UINT_MAX, r->bps);
230 /* we have some time before reaching 2^32 packets per second */
231 est.pps = r->pps;
233 if (d->compat_tc_stats) {
234 d->tc_stats.bps = est.bps;
235 d->tc_stats.pps = est.pps;
238 if (d->tail) {
239 res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est),
240 TCA_STATS_PAD);
241 if (res < 0 || est.bps == r->bps)
242 return res;
243 /* emit 64bit stats only if needed */
244 return gnet_stats_copy(d, TCA_STATS_RATE_EST64, r, sizeof(*r),
245 TCA_STATS_PAD);
248 return 0;
250 EXPORT_SYMBOL(gnet_stats_copy_rate_est);
252 static void
253 __gnet_stats_copy_queue_cpu(struct gnet_stats_queue *qstats,
254 const struct gnet_stats_queue __percpu *q)
256 int i;
258 for_each_possible_cpu(i) {
259 const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i);
261 qstats->qlen = 0;
262 qstats->backlog += qcpu->backlog;
263 qstats->drops += qcpu->drops;
264 qstats->requeues += qcpu->requeues;
265 qstats->overlimits += qcpu->overlimits;
269 static void __gnet_stats_copy_queue(struct gnet_stats_queue *qstats,
270 const struct gnet_stats_queue __percpu *cpu,
271 const struct gnet_stats_queue *q,
272 __u32 qlen)
274 if (cpu) {
275 __gnet_stats_copy_queue_cpu(qstats, cpu);
276 } else {
277 qstats->qlen = q->qlen;
278 qstats->backlog = q->backlog;
279 qstats->drops = q->drops;
280 qstats->requeues = q->requeues;
281 qstats->overlimits = q->overlimits;
284 qstats->qlen = qlen;
288 * gnet_stats_copy_queue - copy queue statistics into statistics TLV
289 * @d: dumping handle
290 * @cpu_q: per cpu queue statistics
291 * @q: queue statistics
292 * @qlen: queue length statistics
294 * Appends the queue statistics to the top level TLV created by
295 * gnet_stats_start_copy(). Using per cpu queue statistics if
296 * they are available.
298 * Returns 0 on success or -1 with the statistic lock released
299 * if the room in the socket buffer was not sufficient.
302 gnet_stats_copy_queue(struct gnet_dump *d,
303 struct gnet_stats_queue __percpu *cpu_q,
304 struct gnet_stats_queue *q, __u32 qlen)
306 struct gnet_stats_queue qstats = {0};
308 __gnet_stats_copy_queue(&qstats, cpu_q, q, qlen);
310 if (d->compat_tc_stats) {
311 d->tc_stats.drops = qstats.drops;
312 d->tc_stats.qlen = qstats.qlen;
313 d->tc_stats.backlog = qstats.backlog;
314 d->tc_stats.overlimits = qstats.overlimits;
317 if (d->tail)
318 return gnet_stats_copy(d, TCA_STATS_QUEUE,
319 &qstats, sizeof(qstats),
320 TCA_STATS_PAD);
322 return 0;
324 EXPORT_SYMBOL(gnet_stats_copy_queue);
327 * gnet_stats_copy_app - copy application specific statistics into statistics TLV
328 * @d: dumping handle
329 * @st: application specific statistics data
330 * @len: length of data
332 * Appends the application specific statistics to the top level TLV created by
333 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
334 * handle is in backward compatibility mode.
336 * Returns 0 on success or -1 with the statistic lock released
337 * if the room in the socket buffer was not sufficient.
340 gnet_stats_copy_app(struct gnet_dump *d, void *st, int len)
342 if (d->compat_xstats) {
343 d->xstats = kmemdup(st, len, GFP_ATOMIC);
344 if (!d->xstats)
345 goto err_out;
346 d->xstats_len = len;
349 if (d->tail)
350 return gnet_stats_copy(d, TCA_STATS_APP, st, len,
351 TCA_STATS_PAD);
353 return 0;
355 err_out:
356 if (d->lock)
357 spin_unlock_bh(d->lock);
358 d->xstats_len = 0;
359 return -1;
361 EXPORT_SYMBOL(gnet_stats_copy_app);
364 * gnet_stats_finish_copy - finish dumping procedure
365 * @d: dumping handle
367 * Corrects the length of the top level TLV to include all TLVs added
368 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
369 * if gnet_stats_start_copy_compat() was used and releases the statistics
370 * lock.
372 * Returns 0 on success or -1 with the statistic lock released
373 * if the room in the socket buffer was not sufficient.
376 gnet_stats_finish_copy(struct gnet_dump *d)
378 if (d->tail)
379 d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
381 if (d->compat_tc_stats)
382 if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
383 sizeof(d->tc_stats), d->padattr) < 0)
384 return -1;
386 if (d->compat_xstats && d->xstats) {
387 if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
388 d->xstats_len, d->padattr) < 0)
389 return -1;
392 if (d->lock)
393 spin_unlock_bh(d->lock);
394 kfree(d->xstats);
395 d->xstats = NULL;
396 d->xstats_len = 0;
397 return 0;
399 EXPORT_SYMBOL(gnet_stats_finish_copy);