[mirror_ubuntu-zesty-kernel.git] / net / core / gen_stats.c

/*
 * net/core/gen_stats.c
 *
 *             This program is free software; you can redistribute it and/or
 *             modify it under the terms of the GNU General Public License
 *             as published by the Free Software Foundation; either version
 *             2 of the License, or (at your option) any later version.
 *
 * Authors:  Thomas Graf <tgraf@suug.ch>
 *           Jamal Hadi Salim
 *           Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 * See Documentation/networking/gen_stats.txt
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/socket.h>
#include <linux/rtnetlink.h>
#include <linux/gen_stats.h>
#include <net/netlink.h>
#include <net/gen_stats.h>


static inline int
gnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size)
{
	if (nla_put(d->skb, type, size, buf))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	spin_unlock_bh(d->lock);
	return -1;
}

/**
 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
 * @skb: socket buffer to put statistics TLVs into
 * @type: TLV type for top level statistic TLV
 * @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
 * @xstats_type: TLV type for backward compatibility xstats TLV
 * @lock: statistics lock
 * @d: dumping handle
 *
 * Initializes the dumping handle, grabs the statistic lock and appends
 * an empty TLV header to the socket buffer for use a container for all
 * other statistic TLVS.
 *
 * The dumping handle is marked to be in backward compatibility mode telling
 * all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
 *
 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
	int xstats_type, spinlock_t *lock, struct gnet_dump *d)
	__acquires(lock)
{
	memset(d, 0, sizeof(*d));

	spin_lock_bh(lock);
	d->lock = lock;
	if (type)
		d->tail = (struct nlattr *)skb_tail_pointer(skb);
	d->skb = skb;
	d->compat_tc_stats = tc_stats_type;
	d->compat_xstats = xstats_type;

	if (d->tail)
		return gnet_stats_copy(d, type, NULL, 0);

	return 0;
}
EXPORT_SYMBOL(gnet_stats_start_copy_compat);

/**
 * gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
 * @skb: socket buffer to put statistics TLVs into
 * @type: TLV type for top level statistic TLV
 * @lock: statistics lock
 * @d: dumping handle
 *
 * Initializes the dumping handle, grabs the statistic lock and appends
 * an empty TLV header to the socket buffer for use a container for all
 * other statistic TLVS.
 *
 * Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,
	struct gnet_dump *d)
{
	return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d);
}
EXPORT_SYMBOL(gnet_stats_start_copy);

static void
__gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
			    struct gnet_stats_basic_cpu __percpu *cpu)
{
	int i;

	for_each_possible_cpu(i) {
		struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i);
		unsigned int start;
		__u64 bytes;
		__u32 packets;

		do {
			start = u64_stats_fetch_begin_irq(&bcpu->syncp);
			bytes = bcpu->bstats.bytes;
			packets = bcpu->bstats.packets;
		} while (u64_stats_fetch_retry_irq(&bcpu->syncp, start));

		bstats->bytes += bcpu->bstats.bytes;
		bstats->packets += bcpu->bstats.packets;
	}
}

void
__gnet_stats_copy_basic(struct gnet_stats_basic_packed *bstats,
			struct gnet_stats_basic_cpu __percpu *cpu,
			struct gnet_stats_basic_packed *b)
{
	if (cpu) {
		__gnet_stats_copy_basic_cpu(bstats, cpu);
	} else {
		bstats->bytes = b->bytes;
		bstats->packets = b->packets;
	}
}
EXPORT_SYMBOL(__gnet_stats_copy_basic);

/**
 * gnet_stats_copy_basic - copy basic statistics into statistic TLV
 * @d: dumping handle
 * @b: basic statistics
 *
 * Appends the basic statistics to the top level TLV created by
 * gnet_stats_start_copy().
 *
 * Returns 0 on success or -1 with the statistic lock released
 * if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_copy_basic(struct gnet_dump *d,
		      struct gnet_stats_basic_cpu __percpu *cpu,
		      struct gnet_stats_basic_packed *b)
{
	struct gnet_stats_basic_packed bstats = {0};

	__gnet_stats_copy_basic(&bstats, cpu, b);

	if (d->compat_tc_stats) {
		d->tc_stats.bytes = bstats.bytes;
		d->tc_stats.packets = bstats.packets;
	}

	if (d->tail) {
		struct gnet_stats_basic sb;

		memset(&sb, 0, sizeof(sb));
		sb.bytes = bstats.bytes;
		sb.packets = bstats.packets;
		return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb));
	}
	return 0;
}
EXPORT_SYMBOL(gnet_stats_copy_basic);

/**
 * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
 * @d: dumping handle
 * @b: basic statistics
 * @r: rate estimator statistics
 *
 * Appends the rate estimator statistics to the top level TLV created by
 * gnet_stats_start_copy().
 *
 * Returns 0 on success or -1 with the statistic lock released
 * if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_copy_rate_est(struct gnet_dump *d,
			 const struct gnet_stats_basic_packed *b,
			 struct gnet_stats_rate_est64 *r)
{
	struct gnet_stats_rate_est est;
	int res;

	if (b && !gen_estimator_active(b, r))
		return 0;

	est.bps = min_t(u64, UINT_MAX, r->bps);
	/* we have some time before reaching 2^32 packets per second */
	est.pps = r->pps;

	if (d->compat_tc_stats) {
		d->tc_stats.bps = est.bps;
		d->tc_stats.pps = est.pps;
	}

	if (d->tail) {
		res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est));
		if (res < 0 || est.bps == r->bps)
			return res;
		/* emit 64bit stats only if needed */
		return gnet_stats_copy(d, TCA_STATS_RATE_EST64, r, sizeof(*r));
	}

	return 0;
}
EXPORT_SYMBOL(gnet_stats_copy_rate_est);

/**
 * gnet_stats_copy_queue - copy queue statistics into statistics TLV
 * @d: dumping handle
 * @q: queue statistics
 * @qlen: queue length statistics
 *
 * Appends the queue statistics to the top level TLV created by
 * gnet_stats_start_copy().
 *
 * Returns 0 on success or -1 with the statistic lock released
 * if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_copy_queue(struct gnet_dump *d,
		      struct gnet_stats_queue *q, __u32 qlen)
{
	q->qlen = qlen;

	if (d->compat_tc_stats) {
		d->tc_stats.drops = q->drops;
		d->tc_stats.qlen = q->qlen;
		d->tc_stats.backlog = q->backlog;
		d->tc_stats.overlimits = q->overlimits;
	}

	if (d->tail)
		return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));

	return 0;
}
EXPORT_SYMBOL(gnet_stats_copy_queue);

/**
 * gnet_stats_copy_app - copy application specific statistics into statistics TLV
 * @d: dumping handle
 * @st: application specific statistics data
 * @len: length of data
 *
 * Appends the application specific statistics to the top level TLV created by
 * gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
 * handle is in backward compatibility mode.
 *
 * Returns 0 on success or -1 with the statistic lock released
 * if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_copy_app(struct gnet_dump *d, void *st, int len)
{
	if (d->compat_xstats) {
		d->xstats = st;
		d->xstats_len = len;
	}

	if (d->tail)
		return gnet_stats_copy(d, TCA_STATS_APP, st, len);

	return 0;
}
EXPORT_SYMBOL(gnet_stats_copy_app);

/**
 * gnet_stats_finish_copy - finish dumping procedure
 * @d: dumping handle
 *
 * Corrects the length of the top level TLV to include all TLVs added
 * by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
 * if gnet_stats_start_copy_compat() was used and releases the statistics
 * lock.
 *
 * Returns 0 on success or -1 with the statistic lock released
 * if the room in the socket buffer was not sufficient.
 */
int
gnet_stats_finish_copy(struct gnet_dump *d)
{
	if (d->tail)
		d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;

	if (d->compat_tc_stats)
		if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
			sizeof(d->tc_stats)) < 0)
			return -1;

	if (d->compat_xstats && d->xstats) {
		if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
			d->xstats_len) < 0)
			return -1;
	}

	spin_unlock_bh(d->lock);
	return 0;
}
EXPORT_SYMBOL(gnet_stats_finish_copy);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* net/core/gen_stats.c
	3	*
	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.
	8	*
	9	* Authors: Thomas Graf <tgraf@suug.ch>
	10	* Jamal Hadi Salim
	11	* Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
	12	*
	13	* See Documentation/networking/gen_stats.txt
	14	*/
	15
	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>
1e90474c	23	#include <net/netlink.h>
1da177e4 LT	24	#include <net/gen_stats.h>
	25
	26
	27	static inline int
	28	gnet_stats_copy(struct gnet_dump d, int type, void buf, int size)
	29	{
14ad6647 DM	30	if (nla_put(d->skb, type, size, buf))
14ad6647 DM	31	goto nla_put_failure;
1da177e4 LT	32	return 0;
1da177e4 LT	33
1e90474c	34	nla_put_failure:
1da177e4 LT	35	spin_unlock_bh(d->lock);
	36	return -1;
	37	}
	38
	39	/**
	40	* gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
	41	* @skb: socket buffer to put statistics TLVs into
	42	* @type: TLV type for top level statistic TLV
	43	* @tc_stats_type: TLV type for backward compatibility struct tc_stats TLV
	44	* @xstats_type: TLV type for backward compatibility xstats TLV
	45	* @lock: statistics lock
	46	* @d: dumping handle
	47	*
	48	* Initializes the dumping handle, grabs the statistic lock and appends
	49	* an empty TLV header to the socket buffer for use a container for all
	50	* other statistic TLVS.
	51	*
	52	* The dumping handle is marked to be in backward compatibility mode telling
	53	* all gnet_stats_copy_XXX() functions to fill a local copy of struct tc_stats.
	54	*
	55	* Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
	56	*/
	57	int
	58	gnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,
	59	int xstats_type, spinlock_t lock, struct gnet_dump d)
9a429c49	60	__acquires(lock)
1da177e4 LT	61	{
1da177e4 LT	62	memset(d, 0, sizeof(*d));
4ec93edb	63
1da177e4 LT	64	spin_lock_bh(lock);
	65	d->lock = lock;
	66	if (type)
1e90474c	67	d->tail = (struct nlattr *)skb_tail_pointer(skb);
1da177e4 LT	68	d->skb = skb;
	69	d->compat_tc_stats = tc_stats_type;
	70	d->compat_xstats = xstats_type;
	71
	72	if (d->tail)
	73	return gnet_stats_copy(d, type, NULL, 0);
	74
	75	return 0;
	76	}
9e34a5b5	77	EXPORT_SYMBOL(gnet_stats_start_copy_compat);
1da177e4 LT	78
	79	/**
	80	* gnet_stats_start_copy_compat - start dumping procedure in compatibility mode
	81	* @skb: socket buffer to put statistics TLVs into
	82	* @type: TLV type for top level statistic TLV
	83	* @lock: statistics lock
	84	* @d: dumping handle
	85	*
	86	* Initializes the dumping handle, grabs the statistic lock and appends
	87	* an empty TLV header to the socket buffer for use a container for all
	88	* other statistic TLVS.
	89	*
	90	* Returns 0 on success or -1 if the room in the socket buffer was not sufficient.
	91	*/
	92	int
	93	gnet_stats_start_copy(struct sk_buff skb, int type, spinlock_t lock,
	94	struct gnet_dump *d)
	95	{
	96	return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d);
	97	}
9e34a5b5	98	EXPORT_SYMBOL(gnet_stats_start_copy);
1da177e4	99
22e0f8b9 JF	100	static void
	101	__gnet_stats_copy_basic_cpu(struct gnet_stats_basic_packed *bstats,
	102	struct gnet_stats_basic_cpu __percpu *cpu)
	103	{
	104	int i;
	105
	106	for_each_possible_cpu(i) {
	107	struct gnet_stats_basic_cpu *bcpu = per_cpu_ptr(cpu, i);
	108	unsigned int start;
	109	__u64 bytes;
	110	__u32 packets;
	111
	112	do {
	113	start = u64_stats_fetch_begin_irq(&bcpu->syncp);
	114	bytes = bcpu->bstats.bytes;
	115	packets = bcpu->bstats.packets;
	116	} while (u64_stats_fetch_retry_irq(&bcpu->syncp, start));
	117
	118	bstats->bytes += bcpu->bstats.bytes;
	119	bstats->packets += bcpu->bstats.packets;
	120	}
	121	}
	122
	123	void
	124	__gnet_stats_copy_basic(struct gnet_stats_basic_packed *bstats,
	125	struct gnet_stats_basic_cpu __percpu *cpu,
	126	struct gnet_stats_basic_packed *b)
	127	{
	128	if (cpu) {
	129	__gnet_stats_copy_basic_cpu(bstats, cpu);
	130	} else {
	131	bstats->bytes = b->bytes;
	132	bstats->packets = b->packets;
	133	}
	134	}
	135	EXPORT_SYMBOL(__gnet_stats_copy_basic);
	136
1da177e4 LT	137	/**
	138	* gnet_stats_copy_basic - copy basic statistics into statistic TLV
	139	* @d: dumping handle
	140	* @b: basic statistics
	141	*
	142	* Appends the basic statistics to the top level TLV created by
	143	* gnet_stats_start_copy().
	144	*
	145	* Returns 0 on success or -1 with the statistic lock released
	146	* if the room in the socket buffer was not sufficient.
	147	*/
	148	int
22e0f8b9 JF	149	gnet_stats_copy_basic(struct gnet_dump *d,
	150	struct gnet_stats_basic_cpu __percpu *cpu,
	151	struct gnet_stats_basic_packed *b)
1da177e4	152	{
22e0f8b9 JF	153	struct gnet_stats_basic_packed bstats = {0};
	154
	155	__gnet_stats_copy_basic(&bstats, cpu, b);
	156
1da177e4	157	if (d->compat_tc_stats) {
22e0f8b9 JF	158	d->tc_stats.bytes = bstats.bytes;
22e0f8b9 JF	159	d->tc_stats.packets = bstats.packets;
1da177e4 LT	160	}
1da177e4 LT	161
c1a8f1f1 ED	162	if (d->tail) {
c1a8f1f1 ED	163	struct gnet_stats_basic sb;
1da177e4	164
c1a8f1f1	165	memset(&sb, 0, sizeof(sb));
22e0f8b9 JF	166	sb.bytes = bstats.bytes;
22e0f8b9 JF	167	sb.packets = bstats.packets;
c1a8f1f1 ED	168	return gnet_stats_copy(d, TCA_STATS_BASIC, &sb, sizeof(sb));
c1a8f1f1 ED	169	}
1da177e4 LT	170	return 0;
1da177e4 LT	171	}
9e34a5b5	172	EXPORT_SYMBOL(gnet_stats_copy_basic);
1da177e4 LT	173
	174	/**
	175	* gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV
	176	* @d: dumping handle
d250a5f9	177	* @b: basic statistics
1da177e4 LT	178	* @r: rate estimator statistics
	179	*
	180	* Appends the rate estimator statistics to the top level TLV created by
	181	* gnet_stats_start_copy().
	182	*
	183	* Returns 0 on success or -1 with the statistic lock released
	184	* if the room in the socket buffer was not sufficient.
	185	*/
	186	int
d250a5f9 ED	187	gnet_stats_copy_rate_est(struct gnet_dump *d,
d250a5f9 ED	188	const struct gnet_stats_basic_packed *b,
45203a3b	189	struct gnet_stats_rate_est64 *r)
1da177e4	190	{
45203a3b ED	191	struct gnet_stats_rate_est est;
	192	int res;
	193
d250a5f9 ED	194	if (b && !gen_estimator_active(b, r))
	195	return 0;
	196
45203a3b ED	197	est.bps = min_t(u64, UINT_MAX, r->bps);
	198	/* we have some time before reaching 2^32 packets per second */
	199	est.pps = r->pps;
	200
1da177e4	201	if (d->compat_tc_stats) {
45203a3b ED	202	d->tc_stats.bps = est.bps;
45203a3b ED	203	d->tc_stats.pps = est.pps;
1da177e4 LT	204	}
1da177e4 LT	205
45203a3b ED	206	if (d->tail) {
	207	res = gnet_stats_copy(d, TCA_STATS_RATE_EST, &est, sizeof(est));
	208	if (res < 0 \|\| est.bps == r->bps)
	209	return res;
	210	/* emit 64bit stats only if needed */
	211	return gnet_stats_copy(d, TCA_STATS_RATE_EST64, r, sizeof(*r));
	212	}
1da177e4 LT	213
	214	return 0;
	215	}
9e34a5b5	216	EXPORT_SYMBOL(gnet_stats_copy_rate_est);
1da177e4 LT	217
	218	/**
	219	* gnet_stats_copy_queue - copy queue statistics into statistics TLV
	220	* @d: dumping handle
	221	* @q: queue statistics
64015853	222	* @qlen: queue length statistics
1da177e4 LT	223	*
	224	* Appends the queue statistics to the top level TLV created by
	225	* gnet_stats_start_copy().
	226	*
	227	* Returns 0 on success or -1 with the statistic lock released
	228	* if the room in the socket buffer was not sufficient.
	229	*/
	230	int
64015853 JF	231	gnet_stats_copy_queue(struct gnet_dump *d,
64015853 JF	232	struct gnet_stats_queue *q, __u32 qlen)
1da177e4	233	{
64015853 JF	234	q->qlen = qlen;
64015853 JF	235
1da177e4 LT	236	if (d->compat_tc_stats) {
	237	d->tc_stats.drops = q->drops;
	238	d->tc_stats.qlen = q->qlen;
	239	d->tc_stats.backlog = q->backlog;
	240	d->tc_stats.overlimits = q->overlimits;
	241	}
	242
	243	if (d->tail)
	244	return gnet_stats_copy(d, TCA_STATS_QUEUE, q, sizeof(*q));
	245
	246	return 0;
	247	}
9e34a5b5	248	EXPORT_SYMBOL(gnet_stats_copy_queue);
1da177e4 LT	249
	250	/**
	251	* gnet_stats_copy_app - copy application specific statistics into statistics TLV
	252	* @d: dumping handle
	253	* @st: application specific statistics data
	254	* @len: length of data
	255	*
e793c0f7	256	* Appends the application specific statistics to the top level TLV created by
1da177e4 LT	257	* gnet_stats_start_copy() and remembers the data for XSTATS if the dumping
	258	* handle is in backward compatibility mode.
	259	*
	260	* Returns 0 on success or -1 with the statistic lock released
	261	* if the room in the socket buffer was not sufficient.
	262	*/
	263	int
	264	gnet_stats_copy_app(struct gnet_dump d, void st, int len)
	265	{
	266	if (d->compat_xstats) {
	267	d->xstats = st;
	268	d->xstats_len = len;
	269	}
	270
	271	if (d->tail)
	272	return gnet_stats_copy(d, TCA_STATS_APP, st, len);
	273
	274	return 0;
	275	}
9e34a5b5	276	EXPORT_SYMBOL(gnet_stats_copy_app);
1da177e4 LT	277
	278	/**
	279	* gnet_stats_finish_copy - finish dumping procedure
	280	* @d: dumping handle
	281	*
	282	* Corrects the length of the top level TLV to include all TLVs added
	283	* by gnet_stats_copy_XXX() calls. Adds the backward compatibility TLVs
	284	* if gnet_stats_start_copy_compat() was used and releases the statistics
	285	* lock.
	286	*
	287	* Returns 0 on success or -1 with the statistic lock released
	288	* if the room in the socket buffer was not sufficient.
	289	*/
	290	int
	291	gnet_stats_finish_copy(struct gnet_dump *d)
	292	{
	293	if (d->tail)
1e90474c	294	d->tail->nla_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
1da177e4 LT	295
	296	if (d->compat_tc_stats)
	297	if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
	298	sizeof(d->tc_stats)) < 0)
	299	return -1;
	300
	301	if (d->compat_xstats && d->xstats) {
	302	if (gnet_stats_copy(d, d->compat_xstats, d->xstats,
	303	d->xstats_len) < 0)
	304	return -1;
	305	}
	306
	307	spin_unlock_bh(d->lock);
	308	return 0;
	309	}
1da177e4	310	EXPORT_SYMBOL(gnet_stats_finish_copy);