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* samples/bpf: Add test/example of using bpf_probe_write_user bpf helperSargun Dhillon2016-07-263-0/+134
| | | | | | | | | | | | | | | | | | | 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>
* bpf: Add bpf_probe_write_user BPF helper to be called in tracersSargun Dhillon2016-07-261-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* bpf: make xdp sample variable names more meaningfulBrenden Blanco2016-07-212-13/+13
| | | | | | | | | | 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>
* bpf: add sample for xdp forwarding and rewriteBrenden Blanco2016-07-202-0/+119
| | | | | | | | | | | | | 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>
* Add sample for adding simple drop program to linkBrenden Blanco2016-07-204-0/+286
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* cgroup: bpf: Add an example to do cgroup checking in BPFMartin KaFai Lau2016-07-015-0/+367
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* samples/bpf: set max locked memory to ulimitedWilliam Tu2016-06-252-0/+6
| | | | | | Signed-off-by: William Tu <u9012063@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* samples/bpf: add verifier testsAlexei Starovoitov2016-05-061-0/+80
| | | | | | | 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>
* samples/bpf: add 'pointer to packet' testsAlexei Starovoitov2016-05-065-0/+281
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2016-05-041-1/+0
|\ | | | | | | | | | | | | | | | | | | 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>
| * samples/bpf: fix trace_output exampleAlexei Starovoitov2016-04-281-1/+0
| | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: like LLC also verify and allow redefining CLANG commandJesper Dangaard Brouer2016-04-292-14/+17
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: allow make to be run from samples/bpf/ directoryJesper Dangaard Brouer2016-04-292-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: add a README file to get users startedJesper Dangaard Brouer2016-04-291-0/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: Makefile verify LLVM compiler avail and bpf target is supportedJesper Dangaard Brouer2016-04-291-0/+18
| | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: add back functionality to redefine LLC commandJesper Dangaard Brouer2016-04-291-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | bpf, samples: add test cases for raw stackDaniel Borkmann2016-04-151-0/+268
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | bpf, samples: don't zero data when not neededDaniel Borkmann2016-04-154-12/+12
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2016-04-096-13/+34
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| * samples/bpf: Enable powerpc supportNaveen N. Rao2016-04-064-4/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * samples/bpf: Use llc in PATH, rather than a hardcoded valueNaveen N. Rao2016-04-061-9/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * samples/bpf: Fix build breakage with map_perf_test_user.cNaveen N. Rao2016-04-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: add tracepoint vs kprobe performance testsAlexei Starovoitov2016-04-084-0/+244
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | samples/bpf: tracepoint exampleAlexei Starovoitov2016-04-081-4/+22
| | | | | | | | | | | | | | | | 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>
* | samples/bpf: add tracepoint support to bpf loaderAlexei Starovoitov2016-04-081-5/+21
|/ | | | | | | | 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>
* samples/bpf: add map performance testAlexei Starovoitov2016-03-093-0/+259
| | | | | | | | 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>
* samples/bpf: stress test bpf_get_stackidAlexei Starovoitov2016-03-091-0/+9
| | | | | | | | 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>
* samples/bpf: add bpf map stress testAlexei Starovoitov2016-03-093-0/+113
| | | | | | | | | | | | | | | | 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>
* samples/bpf: test both pre-alloc and normal mapsAlexei Starovoitov2016-03-081-1/+9
| | | | | | | 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>
* samples/bpf: add map_flags to bpf loaderAlexei Starovoitov2016-03-088-15/+23
| | | | | | | | 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>
* samples/bpf: move ksym_search() into libraryAlexei Starovoitov2016-03-083-66/+69
| | | | | | | | 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>
* samples/bpf: make map creation more verboseAlexei Starovoitov2016-03-081-1/+4
| | | | | | | | | 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>
* samples/bpf: offwaketime exampleAlexei Starovoitov2016-02-204-0/+322
| | | | | | | | | | | | | | | | 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>
* samples/bpf: update tracex[23] examples to use per-cpu mapsAlexei Starovoitov2016-02-064-13/+25
| | | | | Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_ARRAYtom.leiming@gmail.com2016-02-061-0/+92
| | | | | | | | A sanity test for BPF_MAP_TYPE_PERCPU_ARRAY Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_HASHMartin KaFai Lau2016-02-061-0/+96
| | | | | | | | A sanity test for BPF_MAP_TYPE_PERCPU_HASH. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: samples: exclude asm/sysreg.h for arm64Yang Shi2015-11-161-2/+5
| | | | | | | | | | | | | commit 338d4f49d6f7114a017d294ccf7374df4f998edc ("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: Yang Shi <yang.shi@linaro.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: add sample usages for persistent maps/progsDaniel Borkmann2015-11-034-0/+208
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-11-011-0/+12
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| * bpf: sample: define aarch64 specific registersYang Shi2015-10-281-0/+12
| | | | | | | | | | | | | | | | Define aarch64 specific registers for building bpf samples correctly. Signed-off-by: Yang Shi <yang.shi@linaro.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | samples: bpf: add bpf_perf_event_output exampleAlexei Starovoitov2015-10-224-0/+236
| | | | | | | | | | | | | | | | | | | | | | | | | | 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: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | bpf: add unprivileged bpf testsAlexei Starovoitov2015-10-132-10/+355
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add new tests samples/bpf/test_verifier: unpriv: return pointer checks that pointer cannot be returned from the eBPF program unpriv: add const to pointer unpriv: add pointer to pointer unpriv: neg pointer checks that pointer arithmetic is disallowed unpriv: cmp pointer with const unpriv: cmp pointer with pointer checks that comparison of pointers is disallowed Only one case allowed 'void *value = bpf_map_lookup_elem(..); if (value == 0) ...' unpriv: check that printk is disallowed since bpf_trace_printk is not available to unprivileged unpriv: pass pointer to helper function checks that pointers cannot be passed to functions that expect integers If function expects a pointer the verifier allows only that type of pointer. Like 1st argument of bpf_map_lookup_elem() must be pointer to map. (applies to non-root as well) unpriv: indirectly pass pointer on stack to helper function checks that pointer stored into stack cannot be used as part of key passed into bpf_map_lookup_elem() unpriv: mangle pointer on stack 1 unpriv: mangle pointer on stack 2 checks that writing into stack slot that already contains a pointer is disallowed unpriv: read pointer from stack in small chunks checks that < 8 byte read from stack slot that contains a pointer is disallowed unpriv: write pointer into ctx checks that storing pointers into skb->fields is disallowed unpriv: write pointer into map elem value checks that storing pointers into element values is disallowed For example: int bpf_prog(struct __sk_buff *skb) { u32 key = 0; u64 *value = bpf_map_lookup_elem(&map, &key); if (value) *value = (u64) skb; } will be rejected. unpriv: partial copy of pointer checks that doing 32-bit register mov from register containing a pointer is disallowed unpriv: pass pointer to tail_call checks that passing pointer as an index into bpf_tail_call is disallowed unpriv: cmp map pointer with zero checks that comparing map pointer with constant is disallowed unpriv: write into frame pointer checks that frame pointer is read-only (applies to root too) unpriv: cmp of frame pointer checks that R10 cannot be using in comparison unpriv: cmp of stack pointer checks that Rx = R10 - imm is ok, but comparing Rx is not unpriv: obfuscate stack pointer checks that Rx = R10 - imm is ok, but Rx -= imm is not Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | bpf: add bpf_redirect() helperAlexei Starovoitov2015-09-182-1/+27
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Existing bpf_clone_redirect() helper clones skb before redirecting it to RX or TX of destination netdev. Introduce bpf_redirect() helper that does that without cloning. Benchmarked with two hosts using 10G ixgbe NICs. One host is doing line rate pktgen. Another host is configured as: $ tc qdisc add dev $dev ingress $ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \ action bpf run object-file tcbpf1_kern.o section clone_redirect_xmit drop so it receives the packet on $dev and immediately xmits it on $dev + 1 The section 'clone_redirect_xmit' in tcbpf1_kern.o file has the program that does bpf_clone_redirect() and performance is 2.0 Mpps $ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \ action bpf run object-file tcbpf1_kern.o section redirect_xmit drop which is using bpf_redirect() - 2.4 Mpps and using cls_bpf with integrated actions as: $ tc filter add dev $dev root pref 10 \ bpf run object-file tcbpf1_kern.o section redirect_xmit integ_act classid 1 performance is 2.5 Mpps To summarize: u32+act_bpf using clone_redirect - 2.0 Mpps u32+act_bpf using redirect - 2.4 Mpps cls_bpf using redirect - 2.5 Mpps For comparison linux bridge in this setup is doing 2.1 Mpps and ixgbe rx + drop in ip_rcv - 7.8 Mpps Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: fix build warnings and add function read_trace_pipe()Kaixu Xia2015-08-132-9/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | There are two improvements in this patch: 1. Fix the build warnings; 2. Add function read_trace_pipe() to print the result on the screen; Before this patch, we can get the result through /sys/kernel/de bug/tracing/trace_pipe and get nothing on the screen. By applying this patch, the result can be printed on the screen. $ ./tracex6 ... tracex6-705 [003] d..1 131.428593: : CPU-3 19981414 sshd-683 [000] d..1 131.428727: : CPU-0 221682321 sshd-683 [000] d..1 131.428821: : CPU-0 221808766 sshd-683 [000] d..1 131.428950: : CPU-0 221982984 sshd-683 [000] d..1 131.429045: : CPU-0 222111851 tracex6-705 [003] d..1 131.429168: : CPU-3 20757551 sshd-683 [000] d..1 131.429170: : CPU-0 222281240 sshd-683 [000] d..1 131.429261: : CPU-0 222403340 sshd-683 [000] d..1 131.429378: : CPU-0 222561024 ... Signed-off-by: Kaixu Xia <xiakaixu@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* samples/bpf: example of get selected PMU counter valueKaixu Xia2015-08-104-0/+100
| | | | | | | | This is a simple example and shows how to use the new ability to get the selected Hardware PMU counter value. Signed-off-by: Kaixu Xia <xiakaixu@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ebpf: Allow dereferences of PTR_TO_STACK registersAlex Gartrell2015-07-271-0/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | mov %rsp, %r1 ; r1 = rsp add $-8, %r1 ; r1 = rsp - 8 store_q $123, -8(%rsp) ; *(u64*)r1 = 123 <- valid store_q $123, (%r1) ; *(u64*)r1 = 123 <- previously invalid mov $0, %r0 exit ; Always need to exit And we'd get the following error: 0: (bf) r1 = r10 1: (07) r1 += -8 2: (7a) *(u64 *)(r10 -8) = 999 3: (7a) *(u64 *)(r1 +0) = 999 R1 invalid mem access 'fp' Unable to load program We already know that a register is a stack address and the appropriate offset, so we should be able to validate those references as well. Signed-off-by: Alex Gartrell <agartrell@fb.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* samples: bpf: enable trace samples for s390xMichael Holzheu2015-07-096-12/+37
| | | | | | | | | | | The trace bpf samples do not compile on s390x because they use x86 specific fields from the "pt_regs" structure. Fix this and access the fields via new PT_REGS macros. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: BPF based latency tracingDaniel Wagner2015-06-233-0/+206
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Daniel 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: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: introduce current->pid, tgid, uid, gid, comm accessorsAlexei Starovoitov2015-06-163-14/+83
| | | | | | | | | | | | | | | | | | | | | | | eBPF programs attached to kprobes need to filter based on current->pid, uid and other fields, so introduce helper functions: u64 bpf_get_current_pid_tgid(void) Return: current->tgid << 32 | current->pid u64 bpf_get_current_uid_gid(void) Return: current_gid << 32 | current_uid bpf_get_current_comm(char *buf, int size_of_buf) stores current->comm into buf They can be used from the programs attached to TC as well to classify packets based on current task fields. Update tracex2 example to print histogram of write syscalls for each process instead of aggregated for all. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* bpf: allow programs to write to certain skb fieldsAlexei Starovoitov2015-06-072-26/+93
| | | | | | | | | | | | | | | | | | | allow programs read/write skb->mark, tc_index fields and ((struct qdisc_skb_cb *)cb)->data. mark and tc_index are generically useful in TC. cb[0]-cb[4] are primarily used to pass arguments from one program to another called via bpf_tail_call() which can be seen in sockex3_kern.c example. All fields of 'struct __sk_buff' are readable to socket and tc_cls_act progs. mark, tc_index are writeable from tc_cls_act only. cb[0]-cb[4] are writeable by both sockets and tc_cls_act. Add verifier tests and improve sample code. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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