- 02 12月, 2016 1 次提交
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由 Thomas Graf 提交于
Adds a series of tests to verify the functionality of attaching BPF programs at LWT hooks. Also adds a sample which collects a histogram of packet sizes which pass through an LWT hook. $ ./lwt_len_hist.sh Starting netserver with host 'IN(6)ADDR_ANY' port '12865' and family AF_UNSPEC MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.253.2 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 39857.69 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 22 | | 64 -> 127 : 98 | | 128 -> 255 : 213 | | 256 -> 511 : 1444251 |******** | 512 -> 1023 : 660610 |*** | 1024 -> 2047 : 535241 |** | 2048 -> 4095 : 19 | | 4096 -> 8191 : 180 | | 8192 -> 16383 : 5578023 |************************************* | 16384 -> 32767 : 632099 |*** | 32768 -> 65535 : 6575 | | Signed-off-by: NThomas Graf <tgraf@suug.ch> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 01 12月, 2016 1 次提交
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由 Alexei Starovoitov 提交于
Fix the following build error: HOSTCC samples/bpf/test_lru_dist.o ../samples/bpf/test_lru_dist.c:25:22: fatal error: bpf_util.h: No such file or directory This is due to objtree != srctree. Use srctree, since that's where bpf_util.h is located. Fixes: e00c7b21 ("bpf: fix multiple issues in selftest suite and samples") Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NDaniel Borkmann <daniel@iogearbox.net> Tested-by: NDavid Ahern <dsa@cumulusnetworks.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 28 11月, 2016 1 次提交
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由 Daniel Borkmann 提交于
1) The test_lru_map and test_lru_dist fails building on my machine since the sys/resource.h header is not included. 2) test_verifier fails in one test case where we try to call an invalid function, since the verifier log output changed wrt printing function names. 3) Current selftest suite code relies on sysconf(_SC_NPROCESSORS_CONF) for retrieving the number of possible CPUs. This is broken at least in our scenario and really just doesn't work. glibc tries a number of things for retrieving _SC_NPROCESSORS_CONF. First it tries equivalent of /sys/devices/system/cpu/cpu[0-9]* | wc -l, if that fails, depending on the config, it either tries to count CPUs in /proc/cpuinfo, or returns the _SC_NPROCESSORS_ONLN value instead. If /proc/cpuinfo has some issue, it returns just 1 worst case. This oddity is nothing new [1], but semantics/behaviour seems to be settled. _SC_NPROCESSORS_ONLN will parse /sys/devices/system/cpu/online, if that fails it looks into /proc/stat for cpuX entries, and if also that fails for some reason, /proc/cpuinfo is consulted (and returning 1 if unlikely all breaks down). While that might match num_possible_cpus() from the kernel in some cases, it's really not guaranteed with CPU hotplugging, and can result in a buffer overflow since the array in user space could have too few number of slots, and on perpcu map lookup, the kernel will write beyond that memory of the value buffer. William Tu reported such mismatches: [...] The fact that sysconf(_SC_NPROCESSORS_CONF) != num_possible_cpu() happens when CPU hotadd is enabled. For example, in Fusion when setting vcpu.hotadd = "TRUE" or in KVM, setting ./qemu-system-x86_64 -smp 2, maxcpus=4 ... the num_possible_cpu() will be 4 and sysconf() will be 2 [2]. [...] Documentation/cputopology.txt says /sys/devices/system/cpu/possible outputs cpu_possible_mask. That is the same as in num_possible_cpus(), so first step would be to fix the _SC_NPROCESSORS_CONF calls with our own implementation. Later, we could add support to bpf(2) for passing a mask via CPU_SET(3), for example, to just select a subset of CPUs. BPF samples code needs this fix as well (at least so that people stop copying this). Thus, define bpf_num_possible_cpus() once in selftests and import it from there for the sample code to avoid duplicating it. The remaining sysconf(_SC_NPROCESSORS_CONF) in samples are unrelated. After all three issues are fixed, the test suite runs fine again: # make run_tests | grep self selftests: test_verifier [PASS] selftests: test_maps [PASS] selftests: test_lru_map [PASS] selftests: test_kmod.sh [PASS] [1] https://www.sourceware.org/ml/libc-alpha/2011-06/msg00079.html [2] https://www.mail-archive.com/netdev@vger.kernel.org/msg121183.html Fixes: 3059303f ("samples/bpf: update tracex[23] examples to use per-cpu maps") Fixes: 86af8b41 ("Add sample for adding simple drop program to link") Fixes: df570f57 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_ARRAY") Fixes: e1559671 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_HASH") Fixes: ebb676da ("bpf: Print function name in addition to function id") Fixes: 5db58faf ("bpf: Add tests for the LRU bpf_htab") Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Cc: William Tu <u9012063@gmail.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 26 11月, 2016 1 次提交
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由 Daniel Mack 提交于
Add a simple userpace program to demonstrate the new API to attach eBPF programs to cgroups. This is what it does: * Create arraymap in kernel with 4 byte keys and 8 byte values * Load eBPF program The eBPF program accesses the map passed in to store two pieces of information. The number of invocations of the program, which maps to the number of packets received, is stored to key 0. Key 1 is incremented on each iteration by the number of bytes stored in the skb. * Detach any eBPF program previously attached to the cgroup * Attach the new program to the cgroup using BPF_PROG_ATTACH * Once a second, read map[0] and map[1] to see how many bytes and packets were seen on any socket of tasks in the given cgroup. The program takes a cgroup path as 1st argument, and either "ingress" or "egress" as 2nd. Optionally, "drop" can be passed as 3rd argument, which will make the generated eBPF program return 0 instead of 1, so the kernel will drop the packet. libbpf gained two new wrappers for the new syscall commands. Signed-off-by: NDaniel Mack <daniel@zonque.org> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 11月, 2016 1 次提交
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由 Martin KaFai Lau 提交于
This patch has some unit tests and a test_lru_dist. The test_lru_dist reads in the numeric keys from a file. The files used here are generated by a modified fio-genzipf tool originated from the fio test suit. The sample data file can be found here: https://github.com/iamkafai/bpf-lru The zipf.* data files have 100k numeric keys and the key is also ranged from 1 to 100k. The test_lru_dist outputs the number of unique keys (nr_unique). F.e. The following means, 61239 of them is unique out of 100k keys. nr_misses means it cannot be found in the LRU map, so nr_misses must be >= nr_unique. test_lru_dist also simulates a perfect LRU map as a comparison: [root@arch-fb-vm1 ~]# ~/devshare/fb-kernel/linux/samples/bpf/test_lru_dist \ /root/zipf.100k.a1_01.out 4000 1 ... test_parallel_lru_dist (map_type:9 map_flags:0x0): task:0 BPF LRU: nr_unique:23093(/100000) nr_misses:31603(/100000) task:0 Perfect LRU: nr_unique:23093(/100000 nr_misses:34328(/100000) .... test_parallel_lru_dist (map_type:9 map_flags:0x2): task:0 BPF LRU: nr_unique:23093(/100000) nr_misses:31710(/100000) task:0 Perfect LRU: nr_unique:23093(/100000 nr_misses:34328(/100000) [root@arch-fb-vm1 ~]# ~/devshare/fb-kernel/linux/samples/bpf/test_lru_dist \ /root/zipf.100k.a0_01.out 40000 1 ... test_parallel_lru_dist (map_type:9 map_flags:0x0): task:0 BPF LRU: nr_unique:61239(/100000) nr_misses:67054(/100000) task:0 Perfect LRU: nr_unique:61239(/100000 nr_misses:66993(/100000) ... test_parallel_lru_dist (map_type:9 map_flags:0x2): task:0 BPF LRU: nr_unique:61239(/100000) nr_misses:67068(/100000) task:0 Perfect LRU: nr_unique:61239(/100000 nr_misses:66993(/100000) LRU map has also been added to map_perf_test: /* Global LRU */ [root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \ ./map_perf_test 16 $i | awk '{r += $3}END{print r " updates"}'; done 1 cpus: 2934082 updates 4 cpus: 7391434 updates 8 cpus: 6500576 updates /* Percpu LRU */ [root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \ ./map_perf_test 32 $i | awk '{r += $3}END{print r " updates"}'; done 1 cpus: 2896553 updates 4 cpus: 9766395 updates 8 cpus: 17460553 updates Signed-off-by: NMartin KaFai Lau <kafai@fb.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 11月, 2016 1 次提交
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由 Martin KaFai Lau 提交于
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: NAlexei Starovoitov <ast@fb.com> Signed-off-by: NMartin KaFai Lau <kafai@fb.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 10月, 2016 1 次提交
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由 Daniel Borkmann 提交于
Add a start of a test suite for kernel selftests. This moves test_verifier and test_maps over to tools/testing/selftests/bpf/ along with various code improvements and also adds a script for invoking test_bpf module. The test suite can simply be run via selftest framework, f.e.: # cd tools/testing/selftests/bpf/ # make # make run_tests Both test_verifier and test_maps were kind of misplaced in samples/bpf/ directory and we were looking into adding them to selftests for a while now, so it can be picked up by kbuild bot et al and hopefully also get more exposure and thus new test case additions. Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 9月, 2016 2 次提交
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由 Brendan Gregg 提交于
sample instruction pointer and frequency count in a BPF map Signed-off-by: NBrendan Gregg <bgregg@netflix.com> Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Alexei Starovoitov 提交于
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: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 8月, 2016 1 次提交
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由 William Tu 提交于
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: NWilliam Tu <u9012063@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 8月, 2016 1 次提交
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由 Sargun Dhillon 提交于
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: NSargun Dhillon <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Tejun Heo <tj@kernel.org> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 26 7月, 2016 1 次提交
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由 Sargun Dhillon 提交于
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: NSargun Dhillon <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 7月, 2016 2 次提交
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由 Brenden Blanco 提交于
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: NBrenden Blanco <bblanco@plumgrid.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Brenden Blanco 提交于
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 $(</sys/class/net/eth0/ifindex) proto 17: 20403027 drops/s ./pktgen_sample03_burst_single_flow.sh -i $DEV -d $IP -m $MAC -t 4 Running... ctrl^C to stop Device: eth4@0 Result: OK: 11791017(c11788327+d2689) usec, 59622913 (60byte,0frags) 5056638pps 2427Mb/sec (2427186240bps) errors: 0 Device: eth4@1 Result: OK: 11791012(c11787906+d3106) usec, 60526944 (60byte,0frags) 5133311pps 2463Mb/sec (2463989280bps) errors: 0 Device: eth4@2 Result: OK: 11791019(c11788249+d2769) usec, 59868091 (60byte,0frags) 5077431pps 2437Mb/sec (2437166880bps) errors: 0 Device: eth4@3 Result: OK: 11795039(c11792403+d2636) usec, 59483181 (60byte,0frags) 5043067pps 2420Mb/sec (2420672160bps) errors: 0 perf report --no-children: 26.05% ksoftirqd/0 [mlx4_en] [k] mlx4_en_process_rx_cq 17.84% ksoftirqd/0 [mlx4_en] [k] mlx4_en_alloc_frags 5.52% ksoftirqd/0 [mlx4_en] [k] mlx4_en_free_frag 4.90% swapper [kernel.vmlinux] [k] poll_idle 4.14% ksoftirqd/0 [kernel.vmlinux] [k] get_page_from_freelist 2.78% ksoftirqd/0 [kernel.vmlinux] [k] __free_pages_ok 2.57% ksoftirqd/0 [kernel.vmlinux] [k] bpf_map_lookup_elem 2.51% swapper [mlx4_en] [k] mlx4_en_process_rx_cq 1.94% ksoftirqd/0 [kernel.vmlinux] [k] percpu_array_map_lookup_elem 1.45% swapper [mlx4_en] [k] mlx4_en_alloc_frags 1.35% ksoftirqd/0 [kernel.vmlinux] [k] free_one_page 1.33% swapper [kernel.vmlinux] [k] intel_idle 1.04% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5c5 0.96% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c58d 0.93% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c6ee 0.92% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c6b9 0.89% ksoftirqd/0 [kernel.vmlinux] [k] __alloc_pages_nodemask 0.83% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c686 0.83% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5d5 0.78% ksoftirqd/0 [mlx4_en] [k] mlx4_alloc_pages.isra.23 0.77% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5b4 0.77% ksoftirqd/0 [kernel.vmlinux] [k] net_rx_action machine specs: receiver - Intel E5-1630 v3 @ 3.70GHz sender - Intel E5645 @ 2.40GHz Mellanox ConnectX-3 @40G Signed-off-by: NBrenden Blanco <bblanco@plumgrid.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 7月, 2016 1 次提交
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由 Martin KaFai Lau 提交于
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: NMartin KaFai Lau <kafai@fb.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Tejun Heo <tj@kernel.org> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 5月, 2016 1 次提交
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由 Alexei Starovoitov 提交于
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: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 30 4月, 2016 4 次提交
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由 Jesper Dangaard Brouer 提交于
Users are likely to manually compile both LLVM 'llc' and 'clang' tools. Thus, also allow redefining CLANG and verify command exist. Makefile implementation wise, the target that verify the command have been generalized. Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Jesper Dangaard Brouer 提交于
It is not intuitive that 'make' must be run from the top level directory with argument "samples/bpf/" to compile these eBPF samples. Introduce a kbuild make file trick that allow make to be run from the "samples/bpf/" directory itself. It basically change to the top level directory and call "make samples/bpf/" with the "/" slash after the directory name. Also add a clean target that only cleans this directory, by taking advantage of the kbuild external module setting M=$PWD. Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Jesper Dangaard Brouer 提交于
Make compiling samples/bpf more user friendly, by detecting if LLVM compiler tool 'llc' is available, and also detect if the 'bpf' target is available in this version of LLVM. Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Jesper Dangaard Brouer 提交于
It is practical to be-able-to redefine the location of the LLVM command 'llc', because not all distros have a LLVM version with bpf target support. Thus, it is sometimes required to compile LLVM from source, and sometimes it is not desired to overwrite the distros default LLVM version. This feature was removed with 128d1514 ("samples/bpf: Use llc in PATH, rather than a hardcoded value"). Add this features back. Note that it is possible to redefine the LLC on the make command like: make samples/bpf/ LLC=~/git/llvm/build/bin/llc Fixes: 128d1514 ("samples/bpf: Use llc in PATH, rather than a hardcoded value") Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Acked-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 08 4月, 2016 1 次提交
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由 Alexei Starovoitov 提交于
the first microbenchmark does fd=open("/proc/self/comm"); for() { write(fd, "test"); } and on 4 cpus in parallel: writes per sec base (no tracepoints, no kprobes) 930k with kprobe at __set_task_comm() 420k with tracepoint at task:task_rename 730k For kprobe + full bpf program manully fetches oldcomm, newcomm via bpf_probe_read. For tracepint bpf program does nothing, since arguments are copied by tracepoint. 2nd microbenchmark does: fd=open("/dev/urandom"); for() { read(fd, buf); } and on 4 cpus in parallel: reads per sec base (no tracepoints, no kprobes) 300k with kprobe at urandom_read() 279k with tracepoint at random:urandom_read 290k bpf progs attached to kprobe and tracepoint are noop. Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 4月, 2016 1 次提交
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由 Naveen N. Rao 提交于
While at it, remove the generation of .s files and fix some typos in the related comment. Cc: Alexei Starovoitov <ast@fb.com> Cc: David S. Miller <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: NNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 3月, 2016 2 次提交
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由 Alexei Starovoitov 提交于
performance tests for hash map and per-cpu hash map with and without pre-allocation Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Alexei Starovoitov 提交于
this test calls bpf programs from different contexts: from inside of slub, from rcu, from pretty much everywhere, since it kprobes all spin_lock functions. It stresses the bpf hash and percpu map pre-allocation, deallocation logic and call_rcu mechanisms. User space part adding more stress by walking and deleting map elements. Note that due to nature bpf_load.c the earlier kprobe+bpf programs are already active while loader loads new programs, creates new kprobes and attaches them. Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 2月, 2016 1 次提交
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由 Alexei Starovoitov 提交于
This is simplified version of Brendan Gregg's offwaketime: This program shows kernel stack traces and task names that were blocked and "off-CPU", along with the stack traces and task names for the threads that woke them, and the total elapsed time from when they blocked to when they were woken up. The combined stacks, task names, and total time is summarized in kernel context for efficiency. Example: $ sudo ./offwaketime | flamegraph.pl > demo.svg Open demo.svg in the browser as FlameGraph visualization. Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 17 11月, 2015 1 次提交
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由 Yang Shi 提交于
commit 338d4f49 ("arm64: kernel: Add support for Privileged Access Never") includes sysreg.h into futex.h and uaccess.h. But, the inline assembly used by asm/sysreg.h is incompatible with llvm so it will cause BPF samples build failure for ARM64. Since sysreg.h is useless for BPF samples, just exclude it from Makefile via defining __ASM_SYSREG_H. Signed-off-by: NYang Shi <yang.shi@linaro.org> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 03 11月, 2015 1 次提交
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由 Daniel Borkmann 提交于
This patch adds a couple of stand-alone examples on how BPF_OBJ_PIN and BPF_OBJ_GET commands can be used. Example with maps: # ./fds_example -F /sys/fs/bpf/m -P -m -k 1 -v 42 bpf: map fd:3 (Success) bpf: pin ret:(0,Success) bpf: fd:3 u->(1:42) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):42 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 -v 24 bpf: get fd:3 (Success) bpf: fd:3 u->(1:24) ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):24 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -P -m bpf: map fd:3 (Success) bpf: pin ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m -k 1 bpf: get fd:3 (Success) bpf: fd:3 l->(1):0 ret:(0,Success) # ./fds_example -F /sys/fs/bpf/m2 -G -m bpf: get fd:3 (Success) Example with progs: # ./fds_example -F /sys/fs/bpf/p -P -p bpf: prog fd:3 (Success) bpf: pin ret:(0,Success) bpf sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -P -p -o ./sockex1_kern.o bpf: prog fd:5 (Success) bpf: pin ret:(0,Success) bpf: sock:3 <- fd:5 attached ret:(0,Success) # ./fds_example -F /sys/fs/bpf/p2 -G -p bpf: get fd:3 (Success) bpf: sock:4 <- fd:3 attached ret:(0,Success) Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net> Acked-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 10月, 2015 1 次提交
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由 Alexei Starovoitov 提交于
Performance test and example of bpf_perf_event_output(). kprobe is attached to sys_write() and trivial bpf program streams pid+cookie into userspace via PERF_COUNT_SW_BPF_OUTPUT event. Usage: $ sudo ./bld_x64/samples/bpf/trace_output recv 2968913 events per sec Signed-off-by: NAlexei Starovoitov <ast@kernel.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 8月, 2015 1 次提交
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由 Kaixu Xia 提交于
This is a simple example and shows how to use the new ability to get the selected Hardware PMU counter value. Signed-off-by: NKaixu Xia <xiakaixu@huawei.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 23 6月, 2015 1 次提交
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由 Daniel Wagner 提交于
BPF offers another way to generate latency histograms. We attach kprobes at trace_preempt_off and trace_preempt_on and calculate the time it takes to from seeing the off/on transition. The first array is used to store the start time stamp. The key is the CPU id. The second array stores the log2(time diff). We need to use static allocation here (array and not hash tables). The kprobes hooking into trace_preempt_on|off should not calling any dynamic memory allocation or free path. We need to avoid recursivly getting called. Besides that, it reduces jitter in the measurement. CPU 0 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 166723 |*************************************** | 4096 -> 8191 : 19870 |*** | 8192 -> 16383 : 6324 | | 16384 -> 32767 : 1098 | | 32768 -> 65535 : 190 | | 65536 -> 131071 : 179 | | 131072 -> 262143 : 18 | | 262144 -> 524287 : 4 | | 524288 -> 1048575 : 1363 | | CPU 1 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 114042 |*************************************** | 4096 -> 8191 : 9587 |** | 8192 -> 16383 : 4140 | | 16384 -> 32767 : 673 | | 32768 -> 65535 : 179 | | 65536 -> 131071 : 29 | | 131072 -> 262143 : 4 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 364 | | CPU 2 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 40147 |*************************************** | 4096 -> 8191 : 2300 |* | 8192 -> 16383 : 828 | | 16384 -> 32767 : 178 | | 32768 -> 65535 : 59 | | 65536 -> 131071 : 2 | | 131072 -> 262143 : 0 | | 262144 -> 524287 : 1 | | 524288 -> 1048575 : 174 | | CPU 3 latency : count distribution 1 -> 1 : 0 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 0 | | 32 -> 63 : 0 | | 64 -> 127 : 0 | | 128 -> 255 : 0 | | 256 -> 511 : 0 | | 512 -> 1023 : 0 | | 1024 -> 2047 : 0 | | 2048 -> 4095 : 29626 |*************************************** | 4096 -> 8191 : 2704 |** | 8192 -> 16383 : 1090 | | 16384 -> 32767 : 160 | | 32768 -> 65535 : 72 | | 65536 -> 131071 : 32 | | 131072 -> 262143 : 26 | | 262144 -> 524287 : 12 | | 524288 -> 1048575 : 298 | | All this is based on the trace3 examples written by Alexei Starovoitov <ast@plumgrid.com>. Signed-off-by: NDaniel Wagner <daniel.wagner@bmw-carit.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: NAlexei Starovoitov <ast@plumgrid.com> Acked-by: NDaniel Borkmann <daniel@iogearbox.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 5月, 2015 2 次提交
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由 Alexei Starovoitov 提交于
Usage: $ sudo ./sockex3 IP src.port -> dst.port bytes packets 127.0.0.1.42010 -> 127.0.0.1.12865 1568 8 127.0.0.1.59526 -> 127.0.0.1.33778 11422636 173070 127.0.0.1.33778 -> 127.0.0.1.59526 11260224828 341974 127.0.0.1.12865 -> 127.0.0.1.42010 1832 12 IP src.port -> dst.port bytes packets 127.0.0.1.42010 -> 127.0.0.1.12865 1568 8 127.0.0.1.59526 -> 127.0.0.1.33778 23198092 351486 127.0.0.1.33778 -> 127.0.0.1.59526 22972698518 698616 127.0.0.1.12865 -> 127.0.0.1.42010 1832 12 this example is similar to sockex2 in a way that it accumulates per-flow statistics, but it does packet parsing differently. sockex2 inlines full packet parser routine into single bpf program. This sockex3 example have 4 independent programs that parse vlan, mpls, ip, ipv6 and one main program that starts the process. bpf_tail_call() mechanism allows each program to be small and be called on demand potentially multiple times, so that many vlan, mpls, ip in ip, gre encapsulations can be parsed. These and other protocol parsers can be added or removed at runtime. TLVs can be parsed in similar manner. Note, tail_call_cnt dynamic check limits the number of tail calls to 32. Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Alexei Starovoitov 提交于
kprobe example that demonstrates how future seccomp programs may look like. It attaches to seccomp_phase1() function and tail-calls other BPF programs depending on syscall number. Existing optimized classic BPF seccomp programs generated by Chrome look like: if (sd.nr < 121) { if (sd.nr < 57) { if (sd.nr < 22) { if (sd.nr < 7) { if (sd.nr < 4) { if (sd.nr < 1) { check sys_read } else { if (sd.nr < 3) { check sys_write and sys_open } else { check sys_close } } } else { } else { } else { } else { } else { } the future seccomp using native eBPF may look like: bpf_tail_call(&sd, &syscall_jmp_table, sd.nr); which is simpler, faster and leaves more room for per-syscall checks. Usage: $ sudo ./tracex5 <...>-366 [001] d... 4.870033: : read(fd=1, buf=00007f6d5bebf000, size=771) <...>-369 [003] d... 4.870066: : mmap <...>-369 [003] d... 4.870077: : syscall=110 (one of get/set uid/pid/gid) <...>-369 [003] d... 4.870089: : syscall=107 (one of get/set uid/pid/gid) sh-369 [000] d... 4.891740: : read(fd=0, buf=00000000023d1000, size=512) sh-369 [000] d... 4.891747: : write(fd=1, buf=00000000023d3000, size=512) sh-369 [000] d... 4.891747: : read(fd=1, buf=00000000023d3000, size=512) Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 13 5月, 2015 1 次提交
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由 Brenden Blanco 提交于
in-source build of 'make samples/bpf/' was incorrectly using default compiler instead of invoking clang/llvm. out-of-source build was ok. Fixes: a8085782 ("samples: bpf: trivial eBPF program in C") Signed-off-by: NBrenden Blanco <bblanco@plumgrid.com> Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 07 4月, 2015 1 次提交
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由 Alexei Starovoitov 提交于
Commit 608cd71a ("tc: bpf: generalize pedit action") has added the possibility to mangle packet data to BPF programs in the tc pipeline. This patch adds two helpers bpf_l3_csum_replace() and bpf_l4_csum_replace() for fixing up the protocol checksums after the packet mangling. It also adds 'flags' argument to bpf_skb_store_bytes() helper to avoid unnecessary checksum recomputations when BPF programs adjusting l3/l4 checksums and documents all three helpers in uapi header. Moreover, a sample program is added to show how BPF programs can make use of the mangle and csum helpers. Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Acked-by: NDaniel Borkmann <daniel@iogearbox.net> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 02 4月, 2015 4 次提交
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由 Alexei Starovoitov 提交于
One BPF program attaches to kmem_cache_alloc_node() and remembers all allocated objects in the map. Another program attaches to kmem_cache_free() and deletes corresponding object from the map. User space walks the map every second and prints any objects which are older than 1 second. Usage: $ sudo tracex4 Then start few long living processes. The 'tracex4' will print something like this: obj 0xffff880465928000 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff88043181c280 is 13sec old was allocated at ip ffffffff8105dc32 obj 0xffff880465848000 is 8sec old was allocated at ip ffffffff8105dc32 obj 0xffff8804338bc280 is 15sec old was allocated at ip ffffffff8105dc32 $ addr2line -fispe vmlinux ffffffff8105dc32 do_fork at fork.c:1665 As soon as processes exit the memory is reclaimed and 'tracex4' prints nothing. Similar experiment can be done with the __kmalloc()/kfree() pair. Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-10-git-send-email-ast@plumgrid.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Alexei Starovoitov 提交于
BPF C program attaches to blk_mq_start_request()/blk_update_request() kprobe events to calculate IO latency. For every completed block IO event it computes the time delta in nsec and records in a histogram map: map[log10(delta)*10]++ User space reads this histogram map every 2 seconds and prints it as a 'heatmap' using gray shades of text terminal. Black spaces have many events and white spaces have very few events. Left most space is the smallest latency, right most space is the largest latency in the range. Usage: $ sudo ./tracex3 and do 'sudo dd if=/dev/sda of=/dev/null' in other terminal. Observe IO latencies and how different activity (like 'make kernel') affects it. Similar experiments can be done for network transmit latencies, syscalls, etc. '-t' flag prints the heatmap using normal ascii characters: $ sudo ./tracex3 -t heatmap of IO latency # - many events with this latency - few events |1us |10us |100us |1ms |10ms |100ms |1s |10s *ooo. *O.#. # 221 . *# . # 125 .. .o#*.. # 55 . . . . .#O # 37 .# # 175 .#*. # 37 # # 199 . . *#*. # 55 *#..* # 42 # # 266 ...***Oo#*OO**o#* . # 629 # # 271 . .#o* o.*o* # 221 . . o* *#O.. # 50 Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-9-git-send-email-ast@plumgrid.comSigned-off-by: NIngo Molnar <mingo@kernel.org> -
由 Alexei Starovoitov 提交于
this example has two probes in one C file that attach to different kprove events and use two different maps. 1st probe is x64 specific equivalent of dropmon. It attaches to kfree_skb, retrevies 'ip' address of kfree_skb() caller and counts number of packet drops at that 'ip' address. User space prints 'location - count' map every second. 2nd probe attaches to kprobe:sys_write and computes a histogram of different write sizes Usage: $ sudo tracex2 location 0xffffffff81695995 count 1 location 0xffffffff816d0da9 count 2 location 0xffffffff81695995 count 2 location 0xffffffff816d0da9 count 2 location 0xffffffff81695995 count 3 location 0xffffffff816d0da9 count 2 557145+0 records in 557145+0 records out 285258240 bytes (285 MB) copied, 1.02379 s, 279 MB/s syscall write() stats byte_size : count distribution 1 -> 1 : 3 | | 2 -> 3 : 0 | | 4 -> 7 : 0 | | 8 -> 15 : 0 | | 16 -> 31 : 2 | | 32 -> 63 : 3 | | 64 -> 127 : 1 | | 128 -> 255 : 1 | | 256 -> 511 : 0 | | 512 -> 1023 : 1118968 |************************************* | Ctrl-C at any time. Kernel will auto cleanup maps and programs $ addr2line -ape ./bld_x64/vmlinux 0xffffffff81695995 0xffffffff816d0da9 0xffffffff81695995: ./bld_x64/../net/ipv4/icmp.c:1038 0xffffffff816d0da9: ./bld_x64/../net/unix/af_unix.c:1231 Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-8-git-send-email-ast@plumgrid.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
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由 Alexei Starovoitov 提交于
tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 06 12月, 2014 2 次提交
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由 Alexei Starovoitov 提交于
sockex2_kern.c is purposefully large eBPF program in C. llvm compiles ~200 lines of C code into ~300 eBPF instructions. It's similar to __skb_flow_dissect() to demonstrate that complex packet parsing can be done by eBPF. Then it uses (struct flow_keys)->dst IP address (or hash of ipv6 dst) to keep stats of number of packets per IP. User space loads eBPF program, attaches it to loopback interface and prints dest_ip->#packets stats every second. Usage: $sudo samples/bpf/sockex2 ip 127.0.0.1 count 19 ip 127.0.0.1 count 178115 ip 127.0.0.1 count 369437 ip 127.0.0.1 count 559841 ip 127.0.0.1 count 750539 Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Alexei Starovoitov 提交于
this example does the same task as previous socket example in assembler, but this one does it in C. eBPF program in kernel does: /* assume that packet is IPv4, load one byte of IP->proto */ int index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)); long *value; value = bpf_map_lookup_elem(&my_map, &index); if (value) __sync_fetch_and_add(value, 1); Corresponding user space reads map[tcp], map[udp], map[icmp] and prints protocol stats every second Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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