Commit 45203a3b authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net_sched: add 64bit rate estimators 



struct gnet_stats_rate_est contains u32 fields, so the bytes per second
field can wrap at 34360Mbit.

Add a new gnet_stats_rate_est64 structure to get 64bit bps/pps fields,
and switch the kernel to use this structure natively.

This structure is dumped to user space as a new attribute :

TCA_STATS_RATE_EST64

Old tc command will now display the capped bps (to 34360Mbit), instead
of wrapped values, and updated tc command will display correct
information.

Old tc command output, after patch :

eric:~# tc -s -d qd sh dev lo
qdisc pfifo 8001: root refcnt 2 limit 1000p
 Sent 80868245400 bytes 1978837 pkt (dropped 0, overlimits 0 requeues 0)
 rate 34360Mbit 189696pps backlog 0b 0p requeues 0

This patch carefully reorganizes "struct Qdisc" layout to get optimal
performance on SMP.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b41abb42

include/net/act_api.h

+1 −1
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ struct tcf_common { 
	struct tcf_t			tcfc_tm;

	struct gnet_stats_basic_packed	tcfc_bstats;

	struct gnet_stats_queue		tcfc_qstats;

	struct gnet_stats_rate_est	tcfc_rate_est;

	struct gnet_stats_rate_est64	tcfc_rate_est;

	spinlock_t			tcfc_lock;

	struct rcu_head			tcfc_rcu;

};

include/net/gen_stats.h

+5 −5
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ extern int gnet_stats_copy_basic(struct gnet_dump *d, 
				 struct gnet_stats_basic_packed *b);

extern int gnet_stats_copy_rate_est(struct gnet_dump *d,

				    const struct gnet_stats_basic_packed *b,

				    struct gnet_stats_rate_est *r);

				    struct gnet_stats_rate_est64 *r);

extern int gnet_stats_copy_queue(struct gnet_dump *d,

				 struct gnet_stats_queue *q);

extern int gnet_stats_copy_app(struct gnet_dump *d, void *st, int len);
@@ -38,13 +38,13 @@ extern int gnet_stats_copy_app(struct gnet_dump *d, void *st, int len); 
extern int gnet_stats_finish_copy(struct gnet_dump *d);



extern int gen_new_estimator(struct gnet_stats_basic_packed *bstats,

			     struct gnet_stats_rate_est *rate_est,

			     struct gnet_stats_rate_est64 *rate_est,

			     spinlock_t *stats_lock, struct nlattr *opt);

extern void gen_kill_estimator(struct gnet_stats_basic_packed *bstats,

			       struct gnet_stats_rate_est *rate_est);

			       struct gnet_stats_rate_est64 *rate_est);

extern int gen_replace_estimator(struct gnet_stats_basic_packed *bstats,

				 struct gnet_stats_rate_est *rate_est,

				 struct gnet_stats_rate_est64 *rate_est,

				 spinlock_t *stats_lock, struct nlattr *opt);

extern bool gen_estimator_active(const struct gnet_stats_basic_packed *bstats,

				 const struct gnet_stats_rate_est *rate_est);

				 const struct gnet_stats_rate_est64 *rate_est);

#endif

include/net/netfilter/xt_rateest.h

+1 −1
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ struct xt_rateest { 
	struct gnet_stats_basic_packed	bstats;

	spinlock_t			lock;

	/* keep rstats and lock on same cache line to speedup xt_rateest_mt() */

	struct gnet_stats_rate_est	rstats;

	struct gnet_stats_rate_est64	rstats;



	/* following fields not accessed in hot path */

	struct hlist_node		list;

include/net/sch_generic.h

+7 −6
Original line number Diff line number Diff line
@@ -58,14 +58,12 @@ struct Qdisc { 
				      * multiqueue device.

				      */

#define TCQ_F_WARN_NONWC	(1 << 16)

	int			padded;

	u32			limit;

	const struct Qdisc_ops	*ops;

	struct qdisc_size_table	__rcu *stab;

	struct list_head	list;

	u32			handle;

	u32			parent;

	atomic_t		refcnt;

	struct gnet_stats_rate_est	rate_est;

	int			(*reshape_fail)(struct sk_buff *skb,

					struct Qdisc *q);
@@ -76,8 +74,9 @@ struct Qdisc { 
	 */

	struct Qdisc		*__parent;

	struct netdev_queue	*dev_queue;

	struct Qdisc		*next_sched;



	struct gnet_stats_rate_est64	rate_est;

	struct Qdisc		*next_sched;

	struct sk_buff		*gso_skb;

	/*

	 * For performance sake on SMP, we put highly modified fields at the end
@@ -88,8 +87,10 @@ struct Qdisc { 
	unsigned int		__state;

	struct gnet_stats_queue	qstats;

	struct rcu_head		rcu_head;

	spinlock_t		busylock;

	u32			limit;

	int			padded;

	atomic_t		refcnt;



	spinlock_t		busylock ____cacheline_aligned_in_smp;

};



static inline bool qdisc_is_running(const struct Qdisc *qdisc)

include/uapi/linux/gen_stats.h

+11 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ enum { 
	TCA_STATS_RATE_EST,

	TCA_STATS_QUEUE,

	TCA_STATS_APP,

	TCA_STATS_RATE_EST64,

	__TCA_STATS_MAX,

};

#define TCA_STATS_MAX (__TCA_STATS_MAX - 1)
@@ -37,6 +38,16 @@ struct gnet_stats_rate_est { 
	__u32	pps;

};



/**

 * struct gnet_stats_rate_est64 - rate estimator

 * @bps: current byte rate

 * @pps: current packet rate

 */

struct gnet_stats_rate_est64 {

	__u64	bps;

	__u64	pps;

};



/**

 * struct gnet_stats_queue - queuing statistics

 * @qlen: queue length

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