kernel/linux.git/samples/bpf/Makefile, branch v4.9.196

bpf: Add test for bpf_redirect to ipip/ip6tnl

2016-11-13T04:38:07+00:00

The test creates two netns, ns1 and ns2. The host (the default netns) has an ipip or ip6tnl dev configured for tunneling traffic to the ns2. ping VIPS from ns1 <----> host <--tunnel--> ns2 (VIPs at loopback) The test is to have ns1 pinging VIPs configured at the loopback interface in ns2. The VIPs are 10.10.1.102 and 2401:face::66 (which are configured at lo@ns2). [Note: 0x66 => 102]. At ns1, the VIPs are routed _via_ the host. At the host, bpf programs are installed at the veth to redirect packets from a veth to the ipip/ip6tnl. The test is configured in a way so that both ingress and egress can be tested. At ns2, the ipip/ip6tnl dev is configured with the local and remote address specified. The return path is routed to the dev ipip/ip6tnl. During egress test, the host also locally tests pinging the VIPs to ensure that bpf_redirect at egress also works for the direct egress (i.e. not forwarding from dev ve1 to ve2). Acked-by: Alexei Starovoitov Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

samples/bpf: add sampleip example

2016-09-02T17:46:45+00:00

sample instruction pointer and frequency count in a BPF map Signed-off-by: Brendan Gregg Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller

samples/bpf: add perf_event+bpf example

2016-09-02T17:46:45+00:00

The bpf program is called 50 times a second and does hashmap[kern&user_stackid]++ It's primary purpose to check that key bpf helpers like map lookup, update, get_stackid, trace_printk and ctx access are all working. It checks: - PERF_COUNT_HW_CPU_CYCLES on all cpus - PERF_COUNT_HW_CPU_CYCLES for current process and inherited perf_events to children - PERF_COUNT_SW_CPU_CLOCK on all cpus - PERF_COUNT_SW_CPU_CLOCK for current process Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller

samples/bpf: Add tunnel set/get tests.

2016-08-20T05:42:44+00:00

The patch creates sample code exercising bpf_skb_{set,get}_tunnel_key, and bpf_skb_{set,get}_tunnel_opt for GRE, VXLAN, and GENEVE. A native tunnel device is created in a namespace to interact with a lwtunnel device out of the namespace, with metadata enabled. The bpf_skb_set_* program is attached to tc egress and bpf_skb_get_* is attached to egress qdisc. A ping between two tunnels is used to verify correctness and the result of bpf_skb_get_* printed by bpf_trace_printk. Signed-off-by: William Tu Signed-off-by: David S. Miller

samples/bpf: Add test_current_task_under_cgroup test

2016-08-13T04:49:42+00:00

This test has a BPF program which writes the last known pid to call the sync syscall within a given cgroup to a map. The user mode program creates its own mount namespace, and mounts the cgroupsv2 hierarchy in there, as on all current test systems (Ubuntu 16.04, Debian), the cgroupsv2 vfs is unmounted by default. Once it does this, it proceeds to test. The test checks for positive and negative condition. It ensures that when it's part of a given cgroup, its pid is captured in the map, and that when it leaves the cgroup, this doesn't happen. It populate a cgroups arraymap prior to execution in userspace. This means that the program must be run in the same cgroups namespace as the programs that are being traced. Signed-off-by: Sargun Dhillon Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Tejun Heo Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

samples/bpf: Add test/example of using bpf_probe_write_user bpf helper

2016-07-26T01:07:48+00:00

This example shows using a kprobe to act as a dnat mechanism to divert traffic for arbitrary endpoints. It rewrite the arguments to a syscall while they're still in userspace, and before the syscall has a chance to copy the argument into kernel space. Although this is an example, it also acts as a test because the mapped address is 255.255.255.255:555 -> real address, and that's not a legal address to connect to. If the helper is broken, the example will fail on the intermediate steps, as well as the final step to verify the rewrite of userspace memory succeeded. Signed-off-by: Sargun Dhillon Cc: Alexei Starovoitov Cc: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

bpf: add sample for xdp forwarding and rewrite

2016-07-20T04:46:33+00:00

Add a sample that rewrites and forwards packets out on the same interface. Observed single core forwarding performance of ~10Mpps. Since the mlx4 driver under test recycles every single packet page, the perf output shows almost exclusively just the ring management and bpf program work. Slowdowns are likely occurring due to cache misses. Signed-off-by: Brenden Blanco Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

Add sample for adding simple drop program to link

2016-07-20T04:46:32+00:00

Add a sample program that only drops packets at the BPF_PROG_TYPE_XDP_RX hook of a link. With the drop-only program, observed single core rate is ~20Mpps. Other tests were run, for instance without the dropcnt increment or without reading from the packet header, the packet rate was mostly unchanged. $ perf record -a samples/bpf/xdp1 $( Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

cgroup: bpf: Add an example to do cgroup checking in BPF

2016-07-01T20:32:13+00:00

test_cgrp2_array_pin.c: A userland program that creates a bpf_map (BPF_MAP_TYPE_GROUP_ARRAY), pouplates/updates it with a cgroup2's backed fd and pins it to a bpf-fs's file. The pinned file can be loaded by tc and then used by the bpf prog later. This program can also update an existing pinned array and it could be useful for debugging/testing purpose. test_cgrp2_tc_kern.c: A bpf prog which should be loaded by tc. It is to demonstrate the usage of bpf_skb_in_cgroup. test_cgrp2_tc.sh: A script that glues the test_cgrp2_array_pin.c and test_cgrp2_tc_kern.c together. The idea is like: 1. Load the test_cgrp2_tc_kern.o by tc 2. Use test_cgrp2_array_pin.c to populate a BPF_MAP_TYPE_CGROUP_ARRAY with a cgroup fd 3. Do a 'ping -6 ff02::1%ve' to ensure the packet has been dropped because of a match on the cgroup Most of the lines in test_cgrp2_tc.sh is the boilerplate to setup the cgroup/bpf-fs/net-devices/netns...etc. It is not bulletproof on errors but should work well enough and give enough debug info if things did not go well. Signed-off-by: Martin KaFai Lau Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Tejun Heo Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

samples/bpf: add 'pointer to packet' tests

2016-05-06T20:01:54+00:00

parse_simple.c - packet parser exapmle with single length check that filters out udp packets for port 9 parse_varlen.c - variable length parser that understand multiple vlan headers, ipip, ipip6 and ip options to filter out udp or tcp packets on port 9. The packet is parsed layer by layer with multitple length checks. parse_ldabs.c - classic style of packet parsing using LD_ABS instruction. Same functionality as parse_simple. simple = 24.1Mpps per core varlen = 22.7Mpps ldabs = 21.4Mpps Parser with LD_ABS instructions is slower than full direct access parser which does more packet accesses and checks. These examples demonstrate the choice bpf program authors can make between flexibility of the parser vs speed. Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller