linux_dsm_epyc7002/net/mpls/internal.h
Robert Shearman 27d691056b mpls: Packet stats
Having MPLS packet stats is useful for observing network operation and
for diagnosing network problems. In the absence of anything better,
RFC2863 and RFC3813 are used for guidance for which stats to expose
and the semantics of them. In particular rx_noroutes maps to in
unknown protos in RFC2863. The stats are exposed to userspace via
AF_MPLS attributes embedded in the IFLA_STATS_AF_SPEC attribute of
RTM_GETSTATS messages.

All the introduced fields are 64-bit, even error ones, to ensure no
overflow with long uptimes. Per-CPU counters are used to avoid
cache-line contention on the commonly used fields. The other fields
have also been made per-CPU for code to avoid performance problems in
error conditions on the assumption that on some platforms the cost of
atomic operations could be more expensive than sending the packet
(which is what would be done in the success case). If that's not the
case, we could instead not use per-CPU counters for these fields.

Only unicast and non-fragment are exposed at the moment, but other
counters can be exposed in the future either by adding to the end of
struct mpls_link_stats or by additional netlink attributes in the
AF_MPLS IFLA_STATS_AF_SPEC nested attribute.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-17 14:38:43 -05:00

180 lines
4.6 KiB
C

#ifndef MPLS_INTERNAL_H
#define MPLS_INTERNAL_H
#include <net/mpls.h>
struct mpls_entry_decoded {
u32 label;
u8 ttl;
u8 tc;
u8 bos;
};
struct mpls_pcpu_stats {
struct mpls_link_stats stats;
struct u64_stats_sync syncp;
};
struct mpls_dev {
int input_enabled;
struct mpls_pcpu_stats __percpu *stats;
struct ctl_table_header *sysctl;
struct rcu_head rcu;
};
#if BITS_PER_LONG == 32
#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \
do { \
__typeof__(*(mdev)->stats) *ptr = \
raw_cpu_ptr((mdev)->stats); \
local_bh_disable(); \
u64_stats_update_begin(&ptr->syncp); \
ptr->stats.pkts_field++; \
ptr->stats.bytes_field += (len); \
u64_stats_update_end(&ptr->syncp); \
local_bh_enable(); \
} while (0)
#define MPLS_INC_STATS(mdev, field) \
do { \
__typeof__(*(mdev)->stats) *ptr = \
raw_cpu_ptr((mdev)->stats); \
local_bh_disable(); \
u64_stats_update_begin(&ptr->syncp); \
ptr->stats.field++; \
u64_stats_update_end(&ptr->syncp); \
local_bh_enable(); \
} while (0)
#else
#define MPLS_INC_STATS_LEN(mdev, len, pkts_field, bytes_field) \
do { \
this_cpu_inc((mdev)->stats->stats.pkts_field); \
this_cpu_add((mdev)->stats->stats.bytes_field, (len)); \
} while (0)
#define MPLS_INC_STATS(mdev, field) \
this_cpu_inc((mdev)->stats->stats.field)
#endif
struct sk_buff;
#define LABEL_NOT_SPECIFIED (1 << 20)
#define MAX_NEW_LABELS 2
/* This maximum ha length copied from the definition of struct neighbour */
#define VIA_ALEN_ALIGN sizeof(unsigned long)
#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN))
enum mpls_payload_type {
MPT_UNSPEC, /* IPv4 or IPv6 */
MPT_IPV4 = 4,
MPT_IPV6 = 6,
/* Other types not implemented:
* - Pseudo-wire with or without control word (RFC4385)
* - GAL (RFC5586)
*/
};
struct mpls_nh { /* next hop label forwarding entry */
struct net_device __rcu *nh_dev;
unsigned int nh_flags;
u32 nh_label[MAX_NEW_LABELS];
u8 nh_labels;
u8 nh_via_alen;
u8 nh_via_table;
};
/* The route, nexthops and vias are stored together in the same memory
* block:
*
* +----------------------+
* | mpls_route |
* +----------------------+
* | mpls_nh 0 |
* +----------------------+
* | ... |
* +----------------------+
* | mpls_nh n-1 |
* +----------------------+
* | alignment padding |
* +----------------------+
* | via[rt_max_alen] 0 |
* +----------------------+
* | ... |
* +----------------------+
* | via[rt_max_alen] n-1 |
* +----------------------+
*/
struct mpls_route { /* next hop label forwarding entry */
struct rcu_head rt_rcu;
u8 rt_protocol;
u8 rt_payload_type;
u8 rt_max_alen;
unsigned int rt_nhn;
unsigned int rt_nhn_alive;
struct mpls_nh rt_nh[0];
};
#define for_nexthops(rt) { \
int nhsel; struct mpls_nh *nh; \
for (nhsel = 0, nh = (rt)->rt_nh; \
nhsel < (rt)->rt_nhn; \
nh++, nhsel++)
#define change_nexthops(rt) { \
int nhsel; struct mpls_nh *nh; \
for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh); \
nhsel < (rt)->rt_nhn; \
nh++, nhsel++)
#define endfor_nexthops(rt) }
static inline struct mpls_shim_hdr mpls_entry_encode(u32 label, unsigned ttl, unsigned tc, bool bos)
{
struct mpls_shim_hdr result;
result.label_stack_entry =
cpu_to_be32((label << MPLS_LS_LABEL_SHIFT) |
(tc << MPLS_LS_TC_SHIFT) |
(bos ? (1 << MPLS_LS_S_SHIFT) : 0) |
(ttl << MPLS_LS_TTL_SHIFT));
return result;
}
static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr *hdr)
{
struct mpls_entry_decoded result;
unsigned entry = be32_to_cpu(hdr->label_stack_entry);
result.label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
result.ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
result.tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
result.bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
return result;
}
static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev)
{
return rcu_dereference_rtnl(dev->mpls_ptr);
}
int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels,
const u32 label[]);
int nla_get_labels(const struct nlattr *nla, u32 max_labels, u8 *labels,
u32 label[]);
int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table,
u8 via[]);
bool mpls_output_possible(const struct net_device *dev);
unsigned int mpls_dev_mtu(const struct net_device *dev);
bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu);
void mpls_stats_inc_outucastpkts(struct net_device *dev,
const struct sk_buff *skb);
#endif /* MPLS_INTERNAL_H */