// SPDX-License-Identifier: GPL-2.0-or-later/* * net/core/gen_stats.c * * Authors:  Thomas Graf <tgraf@suug.ch> *           Jamal Hadi Salim *           Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> * * See Documentation/networking/gen_stats.rst */ #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>#include <net/sch_generic.h> static inline intgnet_stats_copy(struct gnet_dump *d, int type, void *buf, int size, int padattr){	if (nla_put_64bit(d->skb, type, size, buf, padattr))		goto nla_put_failure;	return 0; nla_put_failure:	if (d->lock)		spin_unlock_bh(d->lock);	kfree(d->xstats);	d->xstats = NULL;	d->xstats_len = 0;	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 * @padattr: padding attribute * * 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. */intgnet_stats_start_copy_compat(struct sk_buff *skb, int type, int tc_stats_type,			     int xstats_type, spinlock_t *lock,			     struct gnet_dump *d, int padattr)	__acquires(lock){	memset(d, 0, sizeof(*d)); 	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;	d->padattr = padattr;	if (lock) {		d->lock = lock;		spin_lock_bh(lock);	}	if (d->tail) {		int ret = gnet_stats_copy(d, type, NULL, 0, padattr); 		/* The initial attribute added in gnet_stats_copy() may be		 * preceded by a padding attribute, in which case d->tail will		 * end up pointing at the padding instead of the real attribute.		 * Fix this so gnet_stats_finish_copy() adjusts the length of		 * the right attribute.		 */		if (ret == 0 && d->tail->nla_type == padattr)			d->tail = (struct nlattr *)((char *)d->tail +						    NLA_ALIGN(d->tail->nla_len));		return ret;	} 	return 0;}EXPORT_SYMBOL(gnet_stats_start_copy_compat); /** * gnet_stats_start_copy - 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 * @padattr: padding attribute * * 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. */intgnet_stats_start_copy(struct sk_buff *skb, int type, spinlock_t *lock,		      struct gnet_dump *d, int padattr){	return gnet_stats_start_copy_compat(skb, type, 0, 0, lock, d, padattr);}EXPORT_SYMBOL(gnet_stats_start_copy); /* Must not be inlined, due to u64_stats seqcount_t lockdep key */void gnet_stats_basic_sync_init(struct gnet_stats_basic_sync *b){	u64_stats_set(&b->bytes, 0);	u64_stats_set(&b->packets, 0);	u64_stats_init(&b->syncp);}EXPORT_SYMBOL(gnet_stats_basic_sync_init); static void gnet_stats_add_basic_cpu(struct gnet_stats_basic_sync *bstats,				     const struct gnet_stats_basic_sync __percpu *cpu){	u64 t_bytes = 0, t_packets = 0;	int i; 	for_each_possible_cpu(i) {		const struct gnet_stats_basic_sync *bcpu = per_cpu_ptr(cpu, i);		unsigned int start;		u64 bytes, packets; 		do {			start = u64_stats_fetch_begin(&bcpu->syncp);			bytes = u64_stats_read(&bcpu->bytes);			packets = u64_stats_read(&bcpu->packets);		} while (u64_stats_fetch_retry(&bcpu->syncp, start)); 		t_bytes += bytes;		t_packets += packets;	}	_bstats_update(bstats, t_bytes, t_packets);} void gnet_stats_add_basic(struct gnet_stats_basic_sync *bstats,			  const struct gnet_stats_basic_sync __percpu *cpu,			  const struct gnet_stats_basic_sync *b, bool running){	unsigned int start;	u64 bytes = 0;	u64 packets = 0; 	WARN_ON_ONCE((cpu || running) && in_hardirq()); 	if (cpu) {		gnet_stats_add_basic_cpu(bstats, cpu);		return;	}	do {		if (running)			start = u64_stats_fetch_begin(&b->syncp);		bytes = u64_stats_read(&b->bytes);		packets = u64_stats_read(&b->packets);	} while (running && u64_stats_fetch_retry(&b->syncp, start)); 	_bstats_update(bstats, bytes, packets);}EXPORT_SYMBOL(gnet_stats_add_basic); static void gnet_stats_read_basic(u64 *ret_bytes, u64 *ret_packets,				  const struct gnet_stats_basic_sync __percpu *cpu,				  const struct gnet_stats_basic_sync *b, bool running){	unsigned int start; 	if (cpu) {		u64 t_bytes = 0, t_packets = 0;		int i; 		for_each_possible_cpu(i) {			const struct gnet_stats_basic_sync *bcpu = per_cpu_ptr(cpu, i);			u64 bytes, packets; 			do {				start = u64_stats_fetch_begin(&bcpu->syncp);				bytes = u64_stats_read(&bcpu->bytes);				packets = u64_stats_read(&bcpu->packets);			} while (u64_stats_fetch_retry(&bcpu->syncp, start)); 			t_bytes += bytes;			t_packets += packets;		}		*ret_bytes = t_bytes;		*ret_packets = t_packets;		return;	}	do {		if (running)			start = u64_stats_fetch_begin(&b->syncp);		*ret_bytes = u64_stats_read(&b->bytes);		*ret_packets = u64_stats_read(&b->packets);	} while (running && u64_stats_fetch_retry(&b->syncp, start));} static int___gnet_stats_copy_basic(struct gnet_dump *d,			 const struct gnet_stats_basic_sync __percpu *cpu,			 const struct gnet_stats_basic_sync *b,			 int type, bool running){	u64 bstats_bytes, bstats_packets; 	gnet_stats_read_basic(&bstats_bytes, &bstats_packets, cpu, b, running); 	if (d->compat_tc_stats && type == TCA_STATS_BASIC) {		d->tc_stats.bytes = bstats_bytes;		d->tc_stats.packets = bstats_packets;	} 	if (d->tail) {		struct gnet_stats_basic sb;		int res; 		memset(&sb, 0, sizeof(sb));		sb.bytes = bstats_bytes;		sb.packets = bstats_packets;		res = gnet_stats_copy(d, type, &sb, sizeof(sb), TCA_STATS_PAD);		if (res < 0 || sb.packets == bstats_packets)			return res;		/* emit 64bit stats only if needed */		return gnet_stats_copy(d, TCA_STATS_PKT64, &bstats_packets,				       sizeof(bstats_packets), TCA_STATS_PAD);	}	return 0;} /** * gnet_stats_copy_basic - copy basic statistics into statistic TLV * @d: dumping handle * @cpu: copy statistic per cpu * @b: basic statistics * @running: true if @b represents a running qdisc, thus @b's *           internal values might change during basic reads. *           Only used if @cpu is NULL * * Context: task; must not be run from IRQ or BH contexts * * 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. */intgnet_stats_copy_basic(struct gnet_dump *d,		      const struct gnet_stats_basic_sync __percpu *cpu,		      const struct gnet_stats_basic_sync *b,		      bool running){	return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC, running);}EXPORT_SYMBOL(gnet_stats_copy_basic); /** * gnet_stats_copy_basic_hw - copy basic hw statistics into statistic TLV * @d: dumping handle * @cpu: copy statistic per cpu * @b: basic statistics * @running: true if @b represents a running qdisc, thus @b's *           internal values might change during basic reads. *           Only used if @cpu is NULL * * Context: task; must not be run from IRQ or BH contexts * * 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. */intgnet_stats_copy_basic_hw(struct gnet_dump *d,			 const struct gnet_stats_basic_sync __percpu *cpu,			 const struct gnet_stats_basic_sync *b,			 bool running){	return ___gnet_stats_copy_basic(d, cpu, b, TCA_STATS_BASIC_HW, running);}EXPORT_SYMBOL(gnet_stats_copy_basic_hw); /** * gnet_stats_copy_rate_est - copy rate estimator statistics into statistics TLV * @d: dumping handle * @rate_est: rate estimator * * 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. */intgnet_stats_copy_rate_est(struct gnet_dump *d,			 struct net_rate_estimator __rcu **rate_est){	struct gnet_stats_rate_est64 sample;	struct gnet_stats_rate_est est;	int res; 	if (!gen_estimator_read(rate_est, &sample))		return 0;	est.bps = min_t(u64, UINT_MAX, sample.bps);	/* we have some time before reaching 2^32 packets per second */	est.pps = sample.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),				      TCA_STATS_PAD);		if (res < 0 || est.bps == sample.bps)			return res;		/* emit 64bit stats only if needed */		return gnet_stats_copy(d, TCA_STATS_RATE_EST64, &sample,				       sizeof(sample), TCA_STATS_PAD);	} 	return 0;}EXPORT_SYMBOL(gnet_stats_copy_rate_est); static void gnet_stats_add_queue_cpu(struct gnet_stats_queue *qstats,				     const struct gnet_stats_queue __percpu *q){	int i; 	for_each_possible_cpu(i) {		const struct gnet_stats_queue *qcpu = per_cpu_ptr(q, i); 		qstats->qlen += READ_ONCE(qcpu->qlen);		qstats->backlog += READ_ONCE(qcpu->backlog);		qstats->drops += READ_ONCE(qcpu->drops);		qstats->requeues += READ_ONCE(qcpu->requeues);		qstats->overlimits += READ_ONCE(qcpu->overlimits);	}} void gnet_stats_add_queue(struct gnet_stats_queue *qstats,			  const struct gnet_stats_queue __percpu *cpu,			  const struct gnet_stats_queue *q){	if (cpu) {		gnet_stats_add_queue_cpu(qstats, cpu);	} else {		qstats->qlen += READ_ONCE(q->qlen);		qstats->backlog += READ_ONCE(q->backlog);		qstats->drops += READ_ONCE(q->drops);		qstats->requeues += READ_ONCE(q->requeues);		qstats->overlimits += READ_ONCE(q->overlimits);	}}EXPORT_SYMBOL(gnet_stats_add_queue); /** * gnet_stats_copy_queue - copy queue statistics into statistics TLV * @d: dumping handle * @cpu_q: per cpu queue statistics * @q: queue statistics * @qlen: queue length statistics * * Appends the queue statistics to the top level TLV created by * gnet_stats_start_copy(). Using per cpu queue statistics if * they are available. * * Returns 0 on success or -1 with the statistic lock released * if the room in the socket buffer was not sufficient. */intgnet_stats_copy_queue(struct gnet_dump *d,		      const struct gnet_stats_queue __percpu *cpu_q,		      const struct gnet_stats_queue *q, __u32 qlen){	struct gnet_stats_queue qstats = {0}; 	gnet_stats_add_queue(&qstats, cpu_q, q);	qstats.qlen = qlen; 	if (d->compat_tc_stats) {		d->tc_stats.drops = qstats.drops;		d->tc_stats.qlen = qstats.qlen;		d->tc_stats.backlog = qstats.backlog;		d->tc_stats.overlimits = qstats.overlimits;	} 	if (d->tail)		return gnet_stats_copy(d, TCA_STATS_QUEUE,				       &qstats, sizeof(qstats),				       TCA_STATS_PAD); 	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. */intgnet_stats_copy_app(struct gnet_dump *d, void *st, int len){	if (d->compat_xstats) {		d->xstats = kmemdup(st, len, GFP_ATOMIC);		if (!d->xstats)			goto err_out;		d->xstats_len = len;	} 	if (d->tail)		return gnet_stats_copy(d, TCA_STATS_APP, st, len,				       TCA_STATS_PAD); 	return 0; err_out:	if (d->lock)		spin_unlock_bh(d->lock);	d->xstats_len = 0;	return -1;}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. */intgnet_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), d->padattr) < 0)			return -1; 	if (d->compat_xstats && d->xstats) {		if (gnet_stats_copy(d, d->compat_xstats, d->xstats,				    d->xstats_len, d->padattr) < 0)			return -1;	} 	if (d->lock)		spin_unlock_bh(d->lock);	kfree(d->xstats);	d->xstats = NULL;	d->xstats_len = 0;	return 0;}EXPORT_SYMBOL(gnet_stats_finish_copy);