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2016-09-29bpf: allow access into map value arraysJosef Bacik
Suppose you have a map array value that is something like this struct foo { unsigned iter; int array[SOME_CONSTANT]; }; You can easily insert this into an array, but you cannot modify the contents of foo->array[] after the fact. This is because we have no way to verify we won't go off the end of the array at verification time. This patch provides a start for this work. We accomplish this by keeping track of a minimum and maximum value a register could be while we're checking the code. Then at the time we try to do an access into a MAP_VALUE we verify that the maximum offset into that region is a valid access into that memory region. So in practice, code such as this unsigned index = 0; if (foo->iter >= SOME_CONSTANT) foo->iter = index; else index = foo->iter++; foo->array[index] = bar; would be allowed, as we can verify that index will always be between 0 and SOME_CONSTANT-1. If you wish to use signed values you'll have to have an extra check to make sure the index isn't less than 0, or do something like index %= SOME_CONSTANT. Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27bpf samples: update tracex5 sample to use __seccomp_filterNaveen N. Rao
seccomp_phase1() does not exist anymore. Instead, update sample to use __seccomp_filter(). While at it, set max locked memory to unlimited. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27bpf samples: fix compiler errors with sockex2 and sockex3Naveen N. Rao
These samples fail to compile as 'struct flow_keys' conflicts with definition in net/flow_dissector.h. Fix the same by renaming the structure used in the sample. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20bpf: add test cases for direct packet accessDaniel Borkmann
Add couple of test cases for direct write and the negative size issue, and also adjust the direct packet access test4 since it asserts that writes are not possible, but since we've just added support for writes, we need to invert the verdict to ACCEPT, of course. Summary: 133 PASSED, 0 FAILED. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-17samples/bpf: add comprehensive ipip, ipip6, ip6ip6 testAlexei Starovoitov
the test creates 3 namespaces with veth connected via bridge. First two namespaces simulate two different hosts with the same IPv4 and IPv6 addresses configured on the tunnel interface and they communicate with outside world via standard tunnels. Third namespace creates collect_md tunnel that is driven by BPF program which selects different remote host (either first or second namespace) based on tcp dest port number while tcp dst ip is the same. This scenario is rough approximation of load balancer use case. The tests check both traditional tunnel configuration and collect_md mode. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-17samples/bpf: extend test_tunnel_bpf.sh with IPIP testAlexei Starovoitov
extend existing tests for vxlan, geneve, gre to include IPIP tunnel. It tests both traditional tunnel configuration and dynamic via bpf helpers. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08bpf: fix range propagation on direct packet accessDaniel Borkmann
LLVM can generate code that tests for direct packet access via skb->data/data_end in a way that currently gets rejected by the verifier, example: [...] 7: (61) r3 = *(u32 *)(r6 +80) 8: (61) r9 = *(u32 *)(r6 +76) 9: (bf) r2 = r9 10: (07) r2 += 54 11: (3d) if r3 >= r2 goto pc+12 R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv R6=ctx R9=pkt(id=0,off=0,r=0) R10=fp 12: (18) r4 = 0xffffff7a 14: (05) goto pc+430 [...] from 11 to 24: R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv R6=ctx R9=pkt(id=0,off=0,r=0) R10=fp 24: (7b) *(u64 *)(r10 -40) = r1 25: (b7) r1 = 0 26: (63) *(u32 *)(r6 +56) = r1 27: (b7) r2 = 40 28: (71) r8 = *(u8 *)(r9 +20) invalid access to packet, off=20 size=1, R9(id=0,off=0,r=0) The reason why this gets rejected despite a proper test is that we currently call find_good_pkt_pointers() only in case where we detect tests like rX > pkt_end, where rX is of type pkt(id=Y,off=Z,r=0) and derived, for example, from a register of type pkt(id=Y,off=0,r=0) pointing to skb->data. find_good_pkt_pointers() then fills the range in the current branch to pkt(id=Y,off=0,r=Z) on success. For above case, we need to extend that to recognize pkt_end >= rX pattern and mark the other branch that is taken on success with the appropriate pkt(id=Y,off=0,r=Z) type via find_good_pkt_pointers(). Since eBPF operates on BPF_JGT (>) and BPF_JGE (>=), these are the only two practical options to test for from what LLVM could have generated, since there's no such thing as BPF_JLT (<) or BPF_JLE (<=) that we would need to take into account as well. After the fix: [...] 7: (61) r3 = *(u32 *)(r6 +80) 8: (61) r9 = *(u32 *)(r6 +76) 9: (bf) r2 = r9 10: (07) r2 += 54 11: (3d) if r3 >= r2 goto pc+12 R1=inv R2=pkt(id=0,off=54,r=0) R3=pkt_end R4=inv R6=ctx R9=pkt(id=0,off=0,r=0) R10=fp 12: (18) r4 = 0xffffff7a 14: (05) goto pc+430 [...] from 11 to 24: R1=inv R2=pkt(id=0,off=54,r=54) R3=pkt_end R4=inv R6=ctx R9=pkt(id=0,off=0,r=54) R10=fp 24: (7b) *(u64 *)(r10 -40) = r1 25: (b7) r1 = 0 26: (63) *(u32 *)(r6 +56) = r1 27: (b7) r2 = 40 28: (71) r8 = *(u8 *)(r9 +20) 29: (bf) r1 = r8 30: (25) if r8 > 0x3c goto pc+47 R1=inv56 R2=imm40 R3=pkt_end R4=inv R6=ctx R8=inv56 R9=pkt(id=0,off=0,r=54) R10=fp 31: (b7) r1 = 1 [...] Verifier test cases are also added in this work, one that demonstrates the mentioned example here and one that tries a bad packet access for the current/fall-through branch (the one with types pkt(id=X,off=Y,r=0), pkt(id=X,off=0,r=0)), then a case with good and bad accesses, and two with both test variants (>, >=). Fixes: 969bf05eb3ce ("bpf: direct packet access") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02samples/bpf: add sampleip exampleBrendan Gregg
sample instruction pointer and frequency count in a BPF map Signed-off-by: Brendan Gregg <bgregg@netflix.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02samples/bpf: add perf_event+bpf exampleAlexei Starovoitov
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 <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-19samples/bpf: Add tunnel set/get tests.William Tu
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 <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Minor overlapping changes for both merge conflicts. Resolution work done by Stephen Rothwell was used as a reference. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-12samples/bpf: add verifier tests for the helper access to the packetAaron Yue
test various corner cases of the helper function access to the packet via crafted XDP programs. Signed-off-by: Aaron Yue <haoxuany@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-12bpf: fix bpf_skb_in_cgroup helper namingDaniel Borkmann
While hashing out BPF's current_task_under_cgroup helper bits, it came to discussion that the skb_in_cgroup helper name was suboptimally chosen. Tejun says: So, I think in_cgroup should mean that the object is in that particular cgroup while under_cgroup in the subhierarchy of that cgroup. Let's rename the other subhierarchy test to under too. I think that'd be a lot less confusing going forward. [...] It's more intuitive and gives us the room to implement the real "in" test if ever necessary in the future. Since this touches uapi bits, we need to change this as long as v4.8 is not yet officially released. Thus, change the helper enum and rename related bits. Fixes: 4a482f34afcc ("cgroup: bpf: Add bpf_skb_in_cgroup_proto") Reference: http://patchwork.ozlabs.org/patch/658500/ Suggested-by: Sargun Dhillon <sargun@sargun.me> Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org>
2016-08-12samples/bpf: Add test_current_task_under_cgroup testSargun Dhillon
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 <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Tejun Heo <tj@kernel.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-10samples/bpf: fix bpf_perf_event_output prototypeAdam Barth
The commit 555c8a8623a3 ("bpf: avoid stack copy and use skb ctx for event output") started using 20 of initially reserved upper 32-bits of 'flags' argument in bpf_perf_event_output(). Adjust corresponding prototype in samples/bpf/bpf_helpers.h Signed-off-by: Adam Barth <arb@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-06samples/bpf: add bpf_map_update_elem() testsAlexei Starovoitov
increase test coverage to check previously missing 'update when full' Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-25samples/bpf: Add test/example of using bpf_probe_write_user bpf helperSargun Dhillon
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 <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-25bpf: Add bpf_probe_write_user BPF helper to be called in tracersSargun Dhillon
This allows user memory to be written to during the course of a kprobe. It shouldn't be used to implement any kind of security mechanism because of TOC-TOU attacks, but rather to debug, divert, and manipulate execution of semi-cooperative processes. Although it uses probe_kernel_write, we limit the address space the probe can write into by checking the space with access_ok. We do this as opposed to calling copy_to_user directly, in order to avoid sleeping. In addition we ensure the threads's current fs / segment is USER_DS and the thread isn't exiting nor a kernel thread. Given this feature is meant for experiments, and it has a risk of crashing the system, and running programs, we print a warning on when a proglet that attempts to use this helper is installed, along with the pid and process name. Signed-off-by: Sargun Dhillon <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-20bpf: make xdp sample variable names more meaningfulBrenden Blanco
The naming choice of index is not terribly descriptive, and dropcnt is in fact incorrect for xdp2. Pick better names for these: ipproto and rxcnt. Signed-off-by: Brenden Blanco <bblanco@plumgrid.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19bpf: add sample for xdp forwarding and rewriteBrenden Blanco
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 <bblanco@plumgrid.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19Add sample for adding simple drop program to linkBrenden Blanco
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: Brenden Blanco <bblanco@plumgrid.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-01cgroup: bpf: Add an example to do cgroup checking in BPFMartin KaFai Lau
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 <kafai@fb.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Tejun Heo <tj@kernel.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25samples/bpf: set max locked memory to ulimitedWilliam Tu
Signed-off-by: William Tu <u9012063@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-06samples/bpf: add verifier testsAlexei Starovoitov
add few tests for "pointer to packet" logic of the verifier Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-06samples/bpf: add 'pointer to packet' testsAlexei Starovoitov
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 <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv4/ip_gre.c Minor conflicts between tunnel bug fixes in net and ipv6 tunnel cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-29samples/bpf: like LLC also verify and allow redefining CLANG commandJesper Dangaard Brouer
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: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-29samples/bpf: allow make to be run from samples/bpf/ directoryJesper Dangaard Brouer
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: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-29samples/bpf: add a README file to get users startedJesper Dangaard Brouer
Getting started with using examples in samples/bpf/ is not straightforward. There are several dependencies, and specific versions of these dependencies. Just compiling the example tool is also slightly obscure, e.g. one need to call make like: make samples/bpf/ Do notice the "/" slash after the directory name. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-29samples/bpf: Makefile verify LLVM compiler avail and bpf target is supportedJesper Dangaard Brouer
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: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-29samples/bpf: add back functionality to redefine LLC commandJesper Dangaard Brouer
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 128d1514be35 ("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: 128d1514be35 ("samples/bpf: Use llc in PATH, rather than a hardcoded value") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-28samples/bpf: fix trace_output exampleAlexei Starovoitov
llvm cannot always recognize memset as builtin function and optimize it away, so just delete it. It was a leftover from testing of bpf_perf_event_output() with large data structures. Fixes: 39111695b1b8 ("samples: bpf: add bpf_perf_event_output example") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14bpf, samples: add test cases for raw stackDaniel Borkmann
This adds test cases mostly around ARG_PTR_TO_RAW_STACK to check the verifier behaviour. [...] #84 raw_stack: no skb_load_bytes OK #85 raw_stack: skb_load_bytes, no init OK #86 raw_stack: skb_load_bytes, init OK #87 raw_stack: skb_load_bytes, spilled regs around bounds OK #88 raw_stack: skb_load_bytes, spilled regs corruption OK #89 raw_stack: skb_load_bytes, spilled regs corruption 2 OK #90 raw_stack: skb_load_bytes, spilled regs + data OK #91 raw_stack: skb_load_bytes, invalid access 1 OK #92 raw_stack: skb_load_bytes, invalid access 2 OK #93 raw_stack: skb_load_bytes, invalid access 3 OK #94 raw_stack: skb_load_bytes, invalid access 4 OK #95 raw_stack: skb_load_bytes, invalid access 5 OK #96 raw_stack: skb_load_bytes, invalid access 6 OK #97 raw_stack: skb_load_bytes, large access OK Summary: 98 PASSED, 0 FAILED Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14bpf, samples: don't zero data when not neededDaniel Borkmann
Remove the zero initialization in the sample programs where appropriate. Note that this is an optimization which is now possible, old programs still doing the zero initialization are just fine as well. Also, make sure we don't have padding issues when we don't memset() the entire struct anymore. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2016-04-07samples/bpf: add tracepoint vs kprobe performance testsAlexei Starovoitov
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: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07samples/bpf: tracepoint exampleAlexei Starovoitov
modify offwaketime to work with sched/sched_switch tracepoint instead of kprobe into finish_task_switch Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07samples/bpf: add tracepoint support to bpf loaderAlexei Starovoitov
Recognize "tracepoint/" section name prefix and attach the program to that tracepoint. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06samples/bpf: Enable powerpc supportNaveen N. Rao
Add the necessary definitions for building bpf samples on ppc. Since ppc doesn't store function return address on the stack, modify how PT_REGS_RET() and PT_REGS_FP() work. Also, introduce PT_REGS_IP() to access the instruction pointer. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06samples/bpf: Use llc in PATH, rather than a hardcoded valueNaveen N. Rao
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: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-06samples/bpf: Fix build breakage with map_perf_test_user.cNaveen N. Rao
Building BPF samples is failing with the below error: samples/bpf/map_perf_test_user.c: In function ‘main’: samples/bpf/map_perf_test_user.c:134:9: error: variable ‘r’ has initializer but incomplete type struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; ^ samples/bpf/map_perf_test_user.c:134:21: error: ‘RLIM_INFINITY’ undeclared (first use in this function) struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; ^ samples/bpf/map_perf_test_user.c:134:21: note: each undeclared identifier is reported only once for each function it appears in samples/bpf/map_perf_test_user.c:134:9: warning: excess elements in struct initializer [enabled by default] struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; ^ samples/bpf/map_perf_test_user.c:134:9: warning: (near initialization for ‘r’) [enabled by default] samples/bpf/map_perf_test_user.c:134:9: warning: excess elements in struct initializer [enabled by default] samples/bpf/map_perf_test_user.c:134:9: warning: (near initialization for ‘r’) [enabled by default] samples/bpf/map_perf_test_user.c:134:16: error: storage size of ‘r’ isn’t known struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; ^ samples/bpf/map_perf_test_user.c:139:2: warning: implicit declaration of function ‘setrlimit’ [-Wimplicit-function-declaration] setrlimit(RLIMIT_MEMLOCK, &r); ^ samples/bpf/map_perf_test_user.c:139:12: error: ‘RLIMIT_MEMLOCK’ undeclared (first use in this function) setrlimit(RLIMIT_MEMLOCK, &r); ^ samples/bpf/map_perf_test_user.c:134:16: warning: unused variable ‘r’ [-Wunused-variable] struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; ^ make[2]: *** [samples/bpf/map_perf_test_user.o] Error 1 Fix this by including the necessary header file. Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: add map performance testAlexei Starovoitov
performance tests for hash map and per-cpu hash map with and without pre-allocation Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: stress test bpf_get_stackidAlexei Starovoitov
increase stress by also calling bpf_get_stackid() from various *spin* functions Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: add bpf map stress testAlexei Starovoitov
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: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: test both pre-alloc and normal mapsAlexei Starovoitov
extend test coveraged to include pre-allocated and run-time alloc maps Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: add map_flags to bpf loaderAlexei Starovoitov
note old loader is compatible with new kernel. map_flags are optional Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: move ksym_search() into libraryAlexei Starovoitov
move ksym search from offwaketime into library to be reused in other tests Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: make map creation more verboseAlexei Starovoitov
map creation is typically the first one to fail when rlimits are too low, not enough memory, etc Make this failure scenario more verbose Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-20samples/bpf: offwaketime exampleAlexei Starovoitov
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: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-06samples/bpf: update tracex[23] examples to use per-cpu mapsAlexei Starovoitov
Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>