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linux-stable/include/uapi/linux/seg6_local.h

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ipv6: sr: define core operations for seg6local lightweight tunnel This patch implements a new type of lightweight tunnel named seg6local. A seg6local lwt is defined by a type of action and a set of parameters. The action represents the operation to perform on the packets matching the lwt's route, and is not necessarily an encapsulation. The set of parameters are arguments for the processing function. Each action is defined in a struct seg6_action_desc within seg6_action_table[]. This structure contains the action, mandatory attributes, the processing function, and a static headroom size required by the action. The mandatory attributes are encoded as a bitmask field. The static headroom is set to a non-zero value when the processing function always add a constant number of bytes to the skb (e.g. the header size for encapsulations). To facilitate rtnetlink-related operations such as parsing, fill_encap, and cmp_encap, each type of action parameter is associated to three function pointers, in seg6_action_params[]. All actions defined in seg6_local.h are detailed in [1]. [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-05 10:38:26 +00:00
/*
* SR-IPv6 implementation
*
* Author:
* David Lebrun <david.lebrun@uclouvain.be>
*
*
* 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.
*/
#ifndef _UAPI_LINUX_SEG6_LOCAL_H
#define _UAPI_LINUX_SEG6_LOCAL_H
#include <linux/seg6.h>
enum {
SEG6_LOCAL_UNSPEC,
SEG6_LOCAL_ACTION,
SEG6_LOCAL_SRH,
SEG6_LOCAL_TABLE,
SEG6_LOCAL_NH4,
SEG6_LOCAL_NH6,
SEG6_LOCAL_IIF,
SEG6_LOCAL_OIF,
ipv6: sr: Add seg6local action End.BPF This patch adds the End.BPF action to the LWT seg6local infrastructure. This action works like any other seg6local End action, meaning that an IPv6 header with SRH is needed, whose DA has to be equal to the SID of the action. It will also advance the SRH to the next segment, the BPF program does not have to take care of this. Since the BPF program may not be a source of instability in the kernel, it is important to ensure that the integrity of the packet is maintained before yielding it back to the IPv6 layer. The hook hence keeps track if the SRH has been altered through the helpers, and re-validates its content if needed with seg6_validate_srh. The state kept for validation is stored in a per-CPU buffer. The BPF program is not allowed to directly write into the packet, and only some fields of the SRH can be altered through the helper bpf_lwt_seg6_store_bytes. Performances profiling has shown that the SRH re-validation does not induce a significant overhead. If the altered SRH is deemed as invalid, the packet is dropped. This validation is also done before executing any action through bpf_lwt_seg6_action, and will not be performed again if the SRH is not modified after calling the action. The BPF program may return 3 types of return codes: - BPF_OK: the End.BPF action will look up the next destination through seg6_lookup_nexthop. - BPF_REDIRECT: if an action has been executed through the bpf_lwt_seg6_action helper, the BPF program should return this value, as the skb's destination is already set and the default lookup should not be performed. - BPF_DROP : the packet will be dropped. Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com> Acked-by: David Lebrun <dlebrun@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-20 13:58:16 +00:00
SEG6_LOCAL_BPF,
seg6: add support for the SRv6 End.DT4 behavior SRv6 End.DT4 is defined in the SRv6 Network Programming [1]. The SRv6 End.DT4 is used to implement IPv4 L3VPN use-cases in multi-tenants environments. It decapsulates the received packets and it performs IPv4 routing lookup in the routing table of the tenant. The SRv6 End.DT4 Linux implementation leverages a VRF device in order to force the routing lookup into the associated routing table. To make the End.DT4 work properly, it must be guaranteed that the routing table used for routing lookup operations is bound to one and only one VRF during the tunnel creation. Such constraint has to be enforced by enabling the VRF strict_mode sysctl parameter, i.e: $ sysctl -wq net.vrf.strict_mode=1. At JANOG44, LINE corporation presented their multi-tenant DC architecture using SRv6 [2]. In the slides, they reported that the Linux kernel is missing the support of SRv6 End.DT4 behavior. The SRv6 End.DT4 behavior can be instantiated using a command similar to the following: $ ip route add 2001:db8::1 encap seg6local action End.DT4 vrftable 100 dev eth0 We introduce the "vrftable" extension in iproute2 in a following patch. [1] https://tools.ietf.org/html/draft-ietf-spring-srv6-network-programming [2] https://speakerdeck.com/line_developers/line-data-center-networking-with-srv6 Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-02 13:05:14 +00:00
SEG6_LOCAL_VRFTABLE,
seg6: add counters support for SRv6 Behaviors This patch provides counters for SRv6 Behaviors as defined in [1], section 6. For each SRv6 Behavior instance, counters defined in [1] are: - the total number of packets that have been correctly processed; - the total amount of traffic in bytes of all packets that have been correctly processed; In addition, this patch introduces a new counter that counts the number of packets that have NOT been properly processed (i.e. errors) by an SRv6 Behavior instance. Counters are not only interesting for network monitoring purposes (i.e. counting the number of packets processed by a given behavior) but they also provide a simple tool for checking whether a behavior instance is working as we expect or not. Counters can be useful for troubleshooting misconfigured SRv6 networks. Indeed, an SRv6 Behavior can silently drop packets for very different reasons (i.e. wrong SID configuration, interfaces set with SID addresses, etc) without any notification/message to the user. Due to the nature of SRv6 networks, diagnostic tools such as ping and traceroute may be ineffective: paths used for reaching a given router can be totally different from the ones followed by probe packets. In addition, paths are often asymmetrical and this makes it even more difficult to keep up with the journey of the packets and to understand which behaviors are actually processing our traffic. When counters are enabled on an SRv6 Behavior instance, it is possible to verify if packets are actually processed by such behavior and what is the outcome of the processing. Therefore, the counters for SRv6 Behaviors offer an non-invasive observability point which can be leveraged for both traffic monitoring and troubleshooting purposes. [1] https://www.rfc-editor.org/rfc/rfc8986.html#name-counters Troubleshooting using SRv6 Behavior counters -------------------------------------------- Let's make a brief example to see how helpful counters can be for SRv6 networks. Let's consider a node where an SRv6 End Behavior receives an SRv6 packet whose Segment Left (SL) is equal to 0. In this case, the End Behavior (which accepts only packets with SL >= 1) discards the packet and increases the error counter. This information can be leveraged by the network operator for troubleshooting. Indeed, the error counter is telling the user that the packet: (i) arrived at the node; (ii) the packet has been taken into account by the SRv6 End behavior; (iii) but an error has occurred during the processing. The error (iii) could be caused by different reasons, such as wrong route settings on the node or due to an invalid SID List carried by the SRv6 packet. Anyway, the error counter is used to exclude that the packet did not arrive at the node or it has not been processed by the behavior at all. Turning on/off counters for SRv6 Behaviors ------------------------------------------ Each SRv6 Behavior instance can be configured, at the time of its creation, to make use of counters. This is done through iproute2 which allows the user to create an SRv6 Behavior instance specifying the optional "count" attribute as shown in the following example: $ ip -6 route add 2001:db8::1 encap seg6local action End count dev eth0 per-behavior counters can be shown by adding "-s" to the iproute2 command line, i.e.: $ ip -s -6 route show 2001:db8::1 2001:db8::1 encap seg6local action End packets 0 bytes 0 errors 0 dev eth0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Impact of counters for SRv6 Behaviors on performance ==================================================== To determine the performance impact due to the introduction of counters in the SRv6 Behavior subsystem, we have carried out extensive tests. We chose to test the throughput achieved by the SRv6 End.DX2 Behavior because, among all the other behaviors implemented so far, it reaches the highest throughput which is around 1.5 Mpps (per core at 2.4 GHz on a Xeon(R) CPU E5-2630 v3) on kernel 5.12-rc2 using packets of size ~ 100 bytes. Three different tests were conducted in order to evaluate the overall throughput of the SRv6 End.DX2 Behavior in the following scenarios: 1) vanilla kernel (without the SRv6 Behavior counters patch) and a single instance of an SRv6 End.DX2 Behavior; 2) patched kernel with SRv6 Behavior counters and a single instance of an SRv6 End.DX2 Behavior with counters turned off; 3) patched kernel with SRv6 Behavior counters and a single instance of SRv6 End.DX2 Behavior with counters turned on. All tests were performed on a testbed deployed on the CloudLab facilities [2], a flexible infrastructure dedicated to scientific research on the future of Cloud Computing. Results of tests are shown in the following table: Scenario (1): average 1504764,81 pps (~1504,76 kpps); std. dev 3956,82 pps Scenario (2): average 1501469,78 pps (~1501,47 kpps); std. dev 2979,85 pps Scenario (3): average 1501315,13 pps (~1501,32 kpps); std. dev 2956,00 pps As can be observed, throughputs achieved in scenarios (2),(3) did not suffer any observable degradation compared to scenario (1). Thanks to Jakub Kicinski and David Ahern for their valuable suggestions and comments provided during the discussion of the proposed RFCs. [2] https://www.cloudlab.us Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 15:44:04 +00:00
SEG6_LOCAL_COUNTERS,
ipv6: sr: define core operations for seg6local lightweight tunnel This patch implements a new type of lightweight tunnel named seg6local. A seg6local lwt is defined by a type of action and a set of parameters. The action represents the operation to perform on the packets matching the lwt's route, and is not necessarily an encapsulation. The set of parameters are arguments for the processing function. Each action is defined in a struct seg6_action_desc within seg6_action_table[]. This structure contains the action, mandatory attributes, the processing function, and a static headroom size required by the action. The mandatory attributes are encoded as a bitmask field. The static headroom is set to a non-zero value when the processing function always add a constant number of bytes to the skb (e.g. the header size for encapsulations). To facilitate rtnetlink-related operations such as parsing, fill_encap, and cmp_encap, each type of action parameter is associated to three function pointers, in seg6_action_params[]. All actions defined in seg6_local.h are detailed in [1]. [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-05 10:38:26 +00:00
__SEG6_LOCAL_MAX,
};
#define SEG6_LOCAL_MAX (__SEG6_LOCAL_MAX - 1)
enum {
SEG6_LOCAL_ACTION_UNSPEC = 0,
/* node segment */
SEG6_LOCAL_ACTION_END = 1,
/* adjacency segment (IPv6 cross-connect) */
SEG6_LOCAL_ACTION_END_X = 2,
/* lookup of next seg NH in table */
SEG6_LOCAL_ACTION_END_T = 3,
/* decap and L2 cross-connect */
SEG6_LOCAL_ACTION_END_DX2 = 4,
/* decap and IPv6 cross-connect */
SEG6_LOCAL_ACTION_END_DX6 = 5,
/* decap and IPv4 cross-connect */
SEG6_LOCAL_ACTION_END_DX4 = 6,
/* decap and lookup of DA in v6 table */
SEG6_LOCAL_ACTION_END_DT6 = 7,
/* decap and lookup of DA in v4 table */
SEG6_LOCAL_ACTION_END_DT4 = 8,
/* binding segment with insertion */
SEG6_LOCAL_ACTION_END_B6 = 9,
/* binding segment with encapsulation */
SEG6_LOCAL_ACTION_END_B6_ENCAP = 10,
/* binding segment with MPLS encap */
SEG6_LOCAL_ACTION_END_BM = 11,
/* lookup last seg in table */
SEG6_LOCAL_ACTION_END_S = 12,
/* forward to SR-unaware VNF with static proxy */
SEG6_LOCAL_ACTION_END_AS = 13,
/* forward to SR-unaware VNF with masquerading */
SEG6_LOCAL_ACTION_END_AM = 14,
ipv6: sr: Add seg6local action End.BPF This patch adds the End.BPF action to the LWT seg6local infrastructure. This action works like any other seg6local End action, meaning that an IPv6 header with SRH is needed, whose DA has to be equal to the SID of the action. It will also advance the SRH to the next segment, the BPF program does not have to take care of this. Since the BPF program may not be a source of instability in the kernel, it is important to ensure that the integrity of the packet is maintained before yielding it back to the IPv6 layer. The hook hence keeps track if the SRH has been altered through the helpers, and re-validates its content if needed with seg6_validate_srh. The state kept for validation is stored in a per-CPU buffer. The BPF program is not allowed to directly write into the packet, and only some fields of the SRH can be altered through the helper bpf_lwt_seg6_store_bytes. Performances profiling has shown that the SRH re-validation does not induce a significant overhead. If the altered SRH is deemed as invalid, the packet is dropped. This validation is also done before executing any action through bpf_lwt_seg6_action, and will not be performed again if the SRH is not modified after calling the action. The BPF program may return 3 types of return codes: - BPF_OK: the End.BPF action will look up the next destination through seg6_lookup_nexthop. - BPF_REDIRECT: if an action has been executed through the bpf_lwt_seg6_action helper, the BPF program should return this value, as the skb's destination is already set and the default lookup should not be performed. - BPF_DROP : the packet will be dropped. Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com> Acked-by: David Lebrun <dlebrun@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-20 13:58:16 +00:00
/* custom BPF action */
SEG6_LOCAL_ACTION_END_BPF = 15,
seg6: add support for SRv6 End.DT46 Behavior IETF RFC 8986 [1] includes the definition of SRv6 End.DT4, End.DT6, and End.DT46 Behaviors. The current SRv6 code in the Linux kernel only implements End.DT4 and End.DT6 which can be used respectively to support IPv4-in-IPv6 and IPv6-in-IPv6 VPNs. With End.DT4 and End.DT6 it is not possible to create a single SRv6 VPN tunnel to carry both IPv4 and IPv6 traffic. The proposed End.DT46 implementation is meant to support the decapsulation of IPv4 and IPv6 traffic coming from a single SRv6 tunnel. The implementation of the SRv6 End.DT46 Behavior in the Linux kernel greatly simplifies the setup and operations of SRv6 VPNs. The SRv6 End.DT46 Behavior leverages the infrastructure of SRv6 End.DT{4,6} Behaviors implemented so far, because it makes use of a VRF device in order to force the routing lookup into the associated routing table. To make the End.DT46 work properly, it must be guaranteed that the routing table used for routing lookup operations is bound to one and only one VRF during the tunnel creation. Such constraint has to be enforced by enabling the VRF strict_mode sysctl parameter, i.e.: $ sysctl -wq net.vrf.strict_mode=1 Note that the same approach is used for the SRv6 End.DT4 Behavior and for the End.DT6 Behavior in VRF mode. The command used to instantiate an SRv6 End.DT46 Behavior is straightforward, i.e.: $ ip -6 route add 2001:db8::1 encap seg6local action End.DT46 vrftable 100 dev vrf100. [1] https://www.rfc-editor.org/rfc/rfc8986.html#name-enddt46-decapsulation-and-s ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Performance and impact of SRv6 End.DT46 Behavior on the SRv6 Networking ======================================================================= This patch aims to add the SRv6 End.DT46 Behavior with minimal impact on the performance of SRv6 End.DT4 and End.DT6 Behaviors. In order to verify this, we tested the performance of the newly introduced SRv6 End.DT46 Behavior and compared it with the performance of SRv6 End.DT{4,6} Behaviors, considering both the patched kernel and the kernel before applying the End.DT46 patch (referred to as vanilla kernel). In details, the following decapsulation scenarios were considered: 1.a) IPv6 traffic in SRv6 End.DT46 Behavior on patched kernel; 1.b) IPv4 traffic in SRv6 End.DT46 Behavior on patched kernel; 2.a) SRv6 End.DT6 Behavior (VRF mode) on patched kernel; 2.b) SRv6 End.DT4 Behavior on patched kernel; 3.a) SRv6 End.DT6 Behavior (VRF mode) on vanilla kernel (without the End.DT46 patch); 3.b) SRv6 End.DT4 Behavior on vanilla kernel (without the End.DT46 patch). All tests were performed on a testbed deployed on the CloudLab [2] facilities. We considered IPv{4,6} traffic handled by a single core (at 2.4 GHz on a Xeon(R) CPU E5-2630 v3) on kernel 5.13-rc1 using packets of size ~ 100 bytes. Scenario (1.a): average 684.70 kpps; std. dev. 0.7 kpps; Scenario (1.b): average 711.69 kpps; std. dev. 1.2 kpps; Scenario (2.a): average 690.70 kpps; std. dev. 1.2 kpps; Scenario (2.b): average 722.22 kpps; std. dev. 1.7 kpps; Scenario (3.a): average 690.02 kpps; std. dev. 2.6 kpps; Scenario (3.b): average 721.91 kpps; std. dev. 1.2 kpps; Considering the results for the patched kernel (1.a, 1.b, 2.a, 2.b) we observe that the performance degradation incurred in using End.DT46 rather than End.DT6 and End.DT4 respectively for IPv6 and IPv4 traffic is minimal, around 0.9% and 1.5%. Such very minimal performance degradation is the price to be paid if one prefers to use a single tunnel capable of handling both types of traffic (IPv4 and IPv6). Comparing the results for End.DT4 and End.DT6 under the patched and the vanilla kernel (2.a, 2.b, 3.a, 3.b) we observe that the introduction of the End.DT46 patch has no impact on the performance of End.DT4 and End.DT6. [2] https://www.cloudlab.us Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-17 17:16:44 +00:00
/* decap and lookup of DA in v4 or v6 table */
SEG6_LOCAL_ACTION_END_DT46 = 16,
ipv6: sr: define core operations for seg6local lightweight tunnel This patch implements a new type of lightweight tunnel named seg6local. A seg6local lwt is defined by a type of action and a set of parameters. The action represents the operation to perform on the packets matching the lwt's route, and is not necessarily an encapsulation. The set of parameters are arguments for the processing function. Each action is defined in a struct seg6_action_desc within seg6_action_table[]. This structure contains the action, mandatory attributes, the processing function, and a static headroom size required by the action. The mandatory attributes are encoded as a bitmask field. The static headroom is set to a non-zero value when the processing function always add a constant number of bytes to the skb (e.g. the header size for encapsulations). To facilitate rtnetlink-related operations such as parsing, fill_encap, and cmp_encap, each type of action parameter is associated to three function pointers, in seg6_action_params[]. All actions defined in seg6_local.h are detailed in [1]. [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-05 10:38:26 +00:00
__SEG6_LOCAL_ACTION_MAX,
};
#define SEG6_LOCAL_ACTION_MAX (__SEG6_LOCAL_ACTION_MAX - 1)
ipv6: sr: Add seg6local action End.BPF This patch adds the End.BPF action to the LWT seg6local infrastructure. This action works like any other seg6local End action, meaning that an IPv6 header with SRH is needed, whose DA has to be equal to the SID of the action. It will also advance the SRH to the next segment, the BPF program does not have to take care of this. Since the BPF program may not be a source of instability in the kernel, it is important to ensure that the integrity of the packet is maintained before yielding it back to the IPv6 layer. The hook hence keeps track if the SRH has been altered through the helpers, and re-validates its content if needed with seg6_validate_srh. The state kept for validation is stored in a per-CPU buffer. The BPF program is not allowed to directly write into the packet, and only some fields of the SRH can be altered through the helper bpf_lwt_seg6_store_bytes. Performances profiling has shown that the SRH re-validation does not induce a significant overhead. If the altered SRH is deemed as invalid, the packet is dropped. This validation is also done before executing any action through bpf_lwt_seg6_action, and will not be performed again if the SRH is not modified after calling the action. The BPF program may return 3 types of return codes: - BPF_OK: the End.BPF action will look up the next destination through seg6_lookup_nexthop. - BPF_REDIRECT: if an action has been executed through the bpf_lwt_seg6_action helper, the BPF program should return this value, as the skb's destination is already set and the default lookup should not be performed. - BPF_DROP : the packet will be dropped. Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com> Acked-by: David Lebrun <dlebrun@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-20 13:58:16 +00:00
enum {
SEG6_LOCAL_BPF_PROG_UNSPEC,
SEG6_LOCAL_BPF_PROG,
SEG6_LOCAL_BPF_PROG_NAME,
__SEG6_LOCAL_BPF_PROG_MAX,
};
#define SEG6_LOCAL_BPF_PROG_MAX (__SEG6_LOCAL_BPF_PROG_MAX - 1)
seg6: add counters support for SRv6 Behaviors This patch provides counters for SRv6 Behaviors as defined in [1], section 6. For each SRv6 Behavior instance, counters defined in [1] are: - the total number of packets that have been correctly processed; - the total amount of traffic in bytes of all packets that have been correctly processed; In addition, this patch introduces a new counter that counts the number of packets that have NOT been properly processed (i.e. errors) by an SRv6 Behavior instance. Counters are not only interesting for network monitoring purposes (i.e. counting the number of packets processed by a given behavior) but they also provide a simple tool for checking whether a behavior instance is working as we expect or not. Counters can be useful for troubleshooting misconfigured SRv6 networks. Indeed, an SRv6 Behavior can silently drop packets for very different reasons (i.e. wrong SID configuration, interfaces set with SID addresses, etc) without any notification/message to the user. Due to the nature of SRv6 networks, diagnostic tools such as ping and traceroute may be ineffective: paths used for reaching a given router can be totally different from the ones followed by probe packets. In addition, paths are often asymmetrical and this makes it even more difficult to keep up with the journey of the packets and to understand which behaviors are actually processing our traffic. When counters are enabled on an SRv6 Behavior instance, it is possible to verify if packets are actually processed by such behavior and what is the outcome of the processing. Therefore, the counters for SRv6 Behaviors offer an non-invasive observability point which can be leveraged for both traffic monitoring and troubleshooting purposes. [1] https://www.rfc-editor.org/rfc/rfc8986.html#name-counters Troubleshooting using SRv6 Behavior counters -------------------------------------------- Let's make a brief example to see how helpful counters can be for SRv6 networks. Let's consider a node where an SRv6 End Behavior receives an SRv6 packet whose Segment Left (SL) is equal to 0. In this case, the End Behavior (which accepts only packets with SL >= 1) discards the packet and increases the error counter. This information can be leveraged by the network operator for troubleshooting. Indeed, the error counter is telling the user that the packet: (i) arrived at the node; (ii) the packet has been taken into account by the SRv6 End behavior; (iii) but an error has occurred during the processing. The error (iii) could be caused by different reasons, such as wrong route settings on the node or due to an invalid SID List carried by the SRv6 packet. Anyway, the error counter is used to exclude that the packet did not arrive at the node or it has not been processed by the behavior at all. Turning on/off counters for SRv6 Behaviors ------------------------------------------ Each SRv6 Behavior instance can be configured, at the time of its creation, to make use of counters. This is done through iproute2 which allows the user to create an SRv6 Behavior instance specifying the optional "count" attribute as shown in the following example: $ ip -6 route add 2001:db8::1 encap seg6local action End count dev eth0 per-behavior counters can be shown by adding "-s" to the iproute2 command line, i.e.: $ ip -s -6 route show 2001:db8::1 2001:db8::1 encap seg6local action End packets 0 bytes 0 errors 0 dev eth0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Impact of counters for SRv6 Behaviors on performance ==================================================== To determine the performance impact due to the introduction of counters in the SRv6 Behavior subsystem, we have carried out extensive tests. We chose to test the throughput achieved by the SRv6 End.DX2 Behavior because, among all the other behaviors implemented so far, it reaches the highest throughput which is around 1.5 Mpps (per core at 2.4 GHz on a Xeon(R) CPU E5-2630 v3) on kernel 5.12-rc2 using packets of size ~ 100 bytes. Three different tests were conducted in order to evaluate the overall throughput of the SRv6 End.DX2 Behavior in the following scenarios: 1) vanilla kernel (without the SRv6 Behavior counters patch) and a single instance of an SRv6 End.DX2 Behavior; 2) patched kernel with SRv6 Behavior counters and a single instance of an SRv6 End.DX2 Behavior with counters turned off; 3) patched kernel with SRv6 Behavior counters and a single instance of SRv6 End.DX2 Behavior with counters turned on. All tests were performed on a testbed deployed on the CloudLab facilities [2], a flexible infrastructure dedicated to scientific research on the future of Cloud Computing. Results of tests are shown in the following table: Scenario (1): average 1504764,81 pps (~1504,76 kpps); std. dev 3956,82 pps Scenario (2): average 1501469,78 pps (~1501,47 kpps); std. dev 2979,85 pps Scenario (3): average 1501315,13 pps (~1501,32 kpps); std. dev 2956,00 pps As can be observed, throughputs achieved in scenarios (2),(3) did not suffer any observable degradation compared to scenario (1). Thanks to Jakub Kicinski and David Ahern for their valuable suggestions and comments provided during the discussion of the proposed RFCs. [2] https://www.cloudlab.us Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-27 15:44:04 +00:00
/* SRv6 Behavior counters are encoded as netlink attributes guaranteeing the
* correct alignment.
* Each counter is identified by a different attribute type (i.e.
* SEG6_LOCAL_CNT_PACKETS).
*
* - SEG6_LOCAL_CNT_PACKETS: identifies a counter that counts the number of
* packets that have been CORRECTLY processed by an SRv6 Behavior instance
* (i.e., packets that generate errors or are dropped are NOT counted).
*
* - SEG6_LOCAL_CNT_BYTES: identifies a counter that counts the total amount
* of traffic in bytes of all packets that have been CORRECTLY processed by
* an SRv6 Behavior instance (i.e., packets that generate errors or are
* dropped are NOT counted).
*
* - SEG6_LOCAL_CNT_ERRORS: identifies a counter that counts the number of
* packets that have NOT been properly processed by an SRv6 Behavior instance
* (i.e., packets that generate errors or are dropped).
*/
enum {
SEG6_LOCAL_CNT_UNSPEC,
SEG6_LOCAL_CNT_PAD, /* pad for 64 bits values */
SEG6_LOCAL_CNT_PACKETS,
SEG6_LOCAL_CNT_BYTES,
SEG6_LOCAL_CNT_ERRORS,
__SEG6_LOCAL_CNT_MAX,
};
#define SEG6_LOCAL_CNT_MAX (__SEG6_LOCAL_CNT_MAX - 1)
ipv6: sr: define core operations for seg6local lightweight tunnel This patch implements a new type of lightweight tunnel named seg6local. A seg6local lwt is defined by a type of action and a set of parameters. The action represents the operation to perform on the packets matching the lwt's route, and is not necessarily an encapsulation. The set of parameters are arguments for the processing function. Each action is defined in a struct seg6_action_desc within seg6_action_table[]. This structure contains the action, mandatory attributes, the processing function, and a static headroom size required by the action. The mandatory attributes are encoded as a bitmask field. The static headroom is set to a non-zero value when the processing function always add a constant number of bytes to the skb (e.g. the header size for encapsulations). To facilitate rtnetlink-related operations such as parsing, fill_encap, and cmp_encap, each type of action parameter is associated to three function pointers, in seg6_action_params[]. All actions defined in seg6_local.h are detailed in [1]. [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-01 Signed-off-by: David Lebrun <david.lebrun@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-05 10:38:26 +00:00
#endif