Commit Graph

67 Commits

Author SHA1 Message Date
Lawrence Brakmo d9925368a6 bpf: Sample BPF program to set buffer sizes
This patch contains a BPF program to set initial receive window to
40 packets and send and receive buffers to 1.5MB. This would usually
be done after doing appropriate checks that indicate the hosts are
far enough away (i.e. large RTT).

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 16:15:14 -07:00
Lawrence Brakmo c400296bf6 bpf: Sample bpf program to set initial window
The sample bpf program, tcp_rwnd_kern.c, sets the initial
advertized window to 40 packets in an environment where
distinct IPv6 prefixes indicate that both hosts are not
in the same data center.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 16:15:13 -07:00
Lawrence Brakmo 61bc4d8daa bpf: Sample bpf program to set SYN/SYN-ACK RTOs
The sample BPF program, tcp_synrto_kern.c, sets the SYN and SYN-ACK
RTOs to 10ms when both hosts are within the same datacenter (i.e.
small RTTs) in an environment where common IPv6 prefixes indicate
both hosts are in the same data center.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 16:15:13 -07:00
Lawrence Brakmo ae16189efb bpf: program to load and attach sock_ops BPF progs
The program load_sock_ops can be used to load sock_ops bpf programs and
to attach it to an existing (v2) cgroup. It can also be used to detach
sock_ops programs.

Examples:
    load_sock_ops [-l] <cg-path> <prog filename>
	Load and attaches a sock_ops program at the specified cgroup.
	If "-l" is used, the program will continue to run to output the
	BPF log buffer.
	If the specified filename does not end in ".o", it appends
	"_kern.o" to the name.

    load_sock_ops -r <cg-path>
	Detaches the currently attached sock_ops program from the
	specified cgroup.

Signed-off-by: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 16:15:13 -07:00
Yonghong Song 00a3855d68 samples/bpf: fix a build problem
tracex5_kern.c build failed with the following error message:
  ../samples/bpf/tracex5_kern.c:12:10: fatal error: 'syscall_nrs.h' file not found
  #include "syscall_nrs.h"
The generated file syscall_nrs.h is put in build/samples/bpf directory,
but this directory is not in include path, hence build failed.

The fix is to add $(obj) into the clang compilation path.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-22 11:35:19 -04:00
David Daney 4b7190e841 samples/bpf: Fix tracex5 to work with MIPS syscalls.
There are two problems:

1) In MIPS the __NR_* macros expand to an expression, this causes the
   sections of the object file to be named like:

  .
  .
  .
  [ 5] kprobe/(5000 + 1) PROGBITS        0000000000000000 000160 ...
  [ 6] kprobe/(5000 + 0) PROGBITS        0000000000000000 000258 ...
  [ 7] kprobe/(5000 + 9) PROGBITS        0000000000000000 000348 ...
  .
  .
  .

The fix here is to use the "asm_offsets" trick to evaluate the macros
in the C compiler and generate a header file with a usable form of the
macros.

2) MIPS syscall numbers start at 5000, so we need a bigger map to hold
the sub-programs.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-14 15:03:23 -04:00
Alexander Alemayhu 69b6a7f743 samples/bpf: add -Wno-unknown-warning-option to clang
I was initially going to remove '-Wno-address-of-packed-member' because I
thought it was not supposed to be there but Daniel suggested using
'-Wno-unknown-warning-option'.

This silences several warnings similiar to the one below

warning: unknown warning option '-Wno-address-of-packed-member' [-Wunknown-warning-option]
1 warning generated.
clang  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.3.1/include -I./arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated  -I./include
 -I./arch/x86/include/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h  \
        -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
        -Wno-compare-distinct-pointer-types \
        -Wno-gnu-variable-sized-type-not-at-end \
        -Wno-address-of-packed-member -Wno-tautological-compare \
        -O2 -emit-llvm -c samples/bpf/xdp_tx_iptunnel_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/xdp_tx_iptunnel_kern.o

$ clang --version

 clang version 3.9.1 (tags/RELEASE_391/final)
 Target: x86_64-unknown-linux-gnu
 Thread model: posix
 InstalledDir: /usr/bin

Signed-off-by: Alexander Alemayhu <alexander@alemayhu.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 16:20:19 -04:00
Chenbo Feng 51570a5ab2 A Sample of using socket cookie and uid for traffic monitoring
Add a sample program to demostrate the possible usage of
get_socket_cookie and get_socket_uid helper function. The program will
store bytes and packets counting of in/out traffic monitored by iptables
and store the stats in a bpf map in per socket base. The owner uid of
the socket will be stored as part of the data entry. A shell script for
running the program is also included.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-23 17:01:57 -07:00
Martin KaFai Lau fb30d4b712 bpf: Add tests for map-in-map
Test cases for array of maps and hash of maps.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22 15:45:45 -07:00
Linus Torvalds 00198dab3b Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "On the kernel side there's two x86 PMU driver fixes and a uprobes fix,
  plus on the tooling side there's a number of fixes and some late
  updates"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  perf sched timehist: Fix invalid period calculation
  perf sched timehist: Remove hardcoded 'comm_width' check at print_summary
  perf sched timehist: Enlarge default 'comm_width'
  perf sched timehist: Honour 'comm_width' when aligning the headers
  perf/x86: Fix overlap counter scheduling bug
  perf/x86/pebs: Fix handling of PEBS buffer overflows
  samples/bpf: Move open_raw_sock to separate header
  samples/bpf: Remove perf_event_open() declaration
  samples/bpf: Be consistent with bpf_load_program bpf_insn parameter
  tools lib bpf: Add bpf_prog_{attach,detach}
  samples/bpf: Switch over to libbpf
  perf diff: Do not overwrite valid build id
  perf annotate: Don't throw error for zero length symbols
  perf bench futex: Fix lock-pi help string
  perf trace: Check if MAP_32BIT is defined (again)
  samples/bpf: Make perf_event_read() static
  uprobes: Fix uprobes on MIPS, allow for a cache flush after ixol breakpoint creation
  samples/bpf: Make samples more libbpf-centric
  tools lib bpf: Add flags to bpf_create_map()
  tools lib bpf: use __u32 from linux/types.h
  ...
2016-12-23 16:49:12 -08:00
Joe Stringer 9899694a7f samples/bpf: Move open_raw_sock to separate header
This function was declared in libbpf.c and was the only remaining
function in this library, but has nothing to do with BPF. Shift it out
into a new header, sock_example.h, and include it from the relevant
samples.

Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20161209024620.31660-8-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-20 12:00:40 -03:00
Joe Stringer 205c8ada31 samples/bpf: Remove perf_event_open() declaration
This declaration was made in samples/bpf/libbpf.c for convenience, but
there's already one in tools/perf/perf-sys.h. Reuse that one.

Committer notes:

Testing it:

  $ make -j4 O=../build/v4.9.0-rc8+ samples/bpf/
  make[1]: Entering directory '/home/build/v4.9.0-rc8+'
    CHK     include/config/kernel.release
    GEN     ./Makefile
    CHK     include/generated/uapi/linux/version.h
    Using /home/acme/git/linux as source for kernel
    CHK     include/generated/utsrelease.h
    CHK     include/generated/timeconst.h
    CHK     include/generated/bounds.h
    CHK     include/generated/asm-offsets.h
    CALL    /home/acme/git/linux/scripts/checksyscalls.sh
    HOSTCC  samples/bpf/test_verifier.o
    HOSTCC  samples/bpf/libbpf.o
    HOSTCC  samples/bpf/../../tools/lib/bpf/bpf.o
    HOSTCC  samples/bpf/test_maps.o
    HOSTCC  samples/bpf/sock_example.o
    HOSTCC  samples/bpf/bpf_load.o
<SNIP>
    HOSTLD  samples/bpf/trace_event
    HOSTLD  samples/bpf/sampleip
    HOSTLD  samples/bpf/tc_l2_redirect
  make[1]: Leaving directory '/home/build/v4.9.0-rc8+'
  $

Also tested the offwaketime resulting from the rebuild, seems to work as
before.

Signed-off-by: Joe Stringer <joe@ovn.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20161209024620.31660-7-joe@ovn.org
[ Use -I$(srctree)/tools/lib/ to support out of source code tree builds ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-20 12:00:40 -03:00
Joe Stringer 43371c83f3 samples/bpf: Switch over to libbpf
Now that libbpf under tools/lib/bpf/* is synced with the version from
samples/bpf, we can get rid most of the libbpf library here.

Committer notes:

Built it in a docker fedora rawhide container and ran it in the f25 host, seems
to work just like it did before this patch, i.e. the switch to tools/lib/bpf/
doesn't seem to have introduced problems and Joe said he tested it with
all the entries in samples/bpf/ and other code he found:

  [root@f5065a7d6272 linux]# make -j4 O=/tmp/build/linux headers_install
  <SNIP>
  [root@f5065a7d6272 linux]# rm -rf /tmp/build/linux/samples/bpf/
  [root@f5065a7d6272 linux]# make -j4 O=/tmp/build/linux samples/bpf/
  make[1]: Entering directory '/tmp/build/linux'
    CHK     include/config/kernel.release
    HOSTCC  scripts/basic/fixdep
    GEN     ./Makefile
    CHK     include/generated/uapi/linux/version.h
    Using /git/linux as source for kernel
    CHK     include/generated/utsrelease.h
    HOSTCC  scripts/basic/bin2c
    HOSTCC  arch/x86/tools/relocs_32.o
    HOSTCC  arch/x86/tools/relocs_64.o
    LD      samples/bpf/built-in.o
  <SNIP>
    HOSTCC  samples/bpf/fds_example.o
    HOSTCC  samples/bpf/sockex1_user.o
  /git/linux/samples/bpf/fds_example.c: In function 'bpf_prog_create':
  /git/linux/samples/bpf/fds_example.c:63:6: warning: passing argument 2 of 'bpf_load_program' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
        insns, insns_cnt, "GPL", 0,
        ^~~~~
  In file included from /git/linux/samples/bpf/libbpf.h:5:0,
                   from /git/linux/samples/bpf/bpf_load.h:4,
                   from /git/linux/samples/bpf/fds_example.c:15:
  /git/linux/tools/lib/bpf/bpf.h:31:5: note: expected 'struct bpf_insn *' but argument is of type 'const struct bpf_insn *'
   int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
       ^~~~~~~~~~~~~~~~
    HOSTCC  samples/bpf/sockex2_user.o
  <SNIP>
    HOSTCC  samples/bpf/xdp_tx_iptunnel_user.o
  clang  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.2.1/include -I/git/linux/arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated  -I/git/linux/include -I./include -I/git/linux/arch/x86/include/uapi -I/git/linux/include/uapi -I./include/generated/uapi -include /git/linux/include/linux/kconfig.h  \
	  -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
	  -Wno-compare-distinct-pointer-types \
	  -Wno-gnu-variable-sized-type-not-at-end \
	  -Wno-address-of-packed-member -Wno-tautological-compare \
	  -O2 -emit-llvm -c /git/linux/samples/bpf/sockex1_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/sockex1_kern.o
    HOSTLD  samples/bpf/tc_l2_redirect
  <SNIP>
    HOSTLD  samples/bpf/lwt_len_hist
    HOSTLD  samples/bpf/xdp_tx_iptunnel
  make[1]: Leaving directory '/tmp/build/linux'
  [root@f5065a7d6272 linux]#

And then, in the host:

  [root@jouet bpf]# mount | grep "docker.*devicemapper\/"
  /dev/mapper/docker-253:0-1705076-9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9 on /var/lib/docker/devicemapper/mnt/9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9 type xfs (rw,relatime,context="system_u:object_r:container_file_t:s0:c73,c276",nouuid,attr2,inode64,sunit=1024,swidth=1024,noquota)
  [root@jouet bpf]# cd /var/lib/docker/devicemapper/mnt/9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9/rootfs/tmp/build/linux/samples/bpf/
  [root@jouet bpf]# file offwaketime
  offwaketime: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=f423d171e0487b2f802b6a792657f0f3c8f6d155, not stripped
  [root@jouet bpf]# readelf -SW offwaketime
  offwaketime         offwaketime_kern.o  offwaketime_user.o
  [root@jouet bpf]# readelf -SW offwaketime_kern.o
  There are 11 section headers, starting at offset 0x700:

  Section Headers:
    [Nr] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
    [ 0]                   NULL            0000000000000000 000000 000000 00      0   0  0
    [ 1] .strtab           STRTAB          0000000000000000 000658 0000a8 00      0   0  1
    [ 2] .text             PROGBITS        0000000000000000 000040 000000 00  AX  0   0  4
    [ 3] kprobe/try_to_wake_up PROGBITS        0000000000000000 000040 0000d8 00  AX  0   0  8
    [ 4] .relkprobe/try_to_wake_up REL             0000000000000000 0005a8 000020 10     10   3  8
    [ 5] tracepoint/sched/sched_switch PROGBITS        0000000000000000 000118 000318 00  AX  0   0  8
    [ 6] .reltracepoint/sched/sched_switch REL             0000000000000000 0005c8 000090 10     10   5  8
    [ 7] maps              PROGBITS        0000000000000000 000430 000050 00  WA  0   0  4
    [ 8] license           PROGBITS        0000000000000000 000480 000004 00  WA  0   0  1
    [ 9] version           PROGBITS        0000000000000000 000484 000004 00  WA  0   0  4
    [10] .symtab           SYMTAB          0000000000000000 000488 000120 18      1   4  8
  Key to Flags:
    W (write), A (alloc), X (execute), M (merge), S (strings)
    I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
    O (extra OS processing required) o (OS specific), p (processor specific)
    [root@jouet bpf]# ./offwaketime | head -3
  qemu-system-x86;entry_SYSCALL_64_fastpath;sys_ppoll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;hrtimer_wakeup;__hrtimer_run_queues;hrtimer_interrupt;local_apic_timer_interrupt;smp_apic_timer_interrupt;__irqentry_text_start;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;rest_init;start_kernel;x86_64_start_reservations;x86_64_start_kernel;start_cpu;;swapper/0 4
  firefox;entry_SYSCALL_64_fastpath;sys_poll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;pollwake;__wake_up_common;__wake_up_sync_key;pipe_write;__vfs_write;vfs_write;sys_write;entry_SYSCALL_64_fastpath;;Timer 1
  swapper/2;start_cpu;start_secondary;cpu_startup_entry;schedule_preempt_disabled;schedule;__schedule;-;---;; 61
  [root@jouet bpf]#

Signed-off-by: Joe Stringer <joe@ovn.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: 5c40f54a52.patch
Link: http://lkml.kernel.org/n/tip-xr8twtx7sjh5821g8qw47yxk@git.kernel.org
[ Use -I$(srctree)/tools/lib/ to support out of source code tree builds, as noticed by Wang Nan ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-20 12:00:38 -03:00
Linus Torvalds 41e0e24b45 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - prototypes for x86 asm-exported symbols (Adam Borowski) and a warning
   about missing CRCs (Nick Piggin)

 - asm-exports fix for LTO (Nicolas Pitre)

 - thin archives improvements (Nick Piggin)

 - linker script fix for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION (Nick
   Piggin)

 - genksyms support for __builtin_va_list keyword

 - misc minor fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  x86/kbuild: enable modversions for symbols exported from asm
  kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case
  scripts/kallsyms: remove last remnants of --page-offset option
  make use of make variable CURDIR instead of calling pwd
  kbuild: cmd_export_list: tighten the sed script
  kbuild: minor improvement for thin archives build
  kbuild: modpost warn if export version crc is missing
  kbuild: keep data tables through dead code elimination
  kbuild: improve linker compatibility with lib-ksyms.o build
  genksyms: Regenerate parser
  kbuild/genksyms: handle va_list type
  kbuild: thin archives for multi-y targets
  kbuild: kallsyms allow 3-pass generation if symbols size has changed
2016-12-17 16:24:13 -08:00
Uwe Kleine-König e19b7cee02 make use of make variable CURDIR instead of calling pwd
make already provides the current working directory in a variable, so make
use of it instead of forking a shell. Also replace usage of PWD by
CURDIR. PWD is provided by most shells, but not all, so this makes the
build system more robust.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-12-11 12:12:56 +01:00
Martin KaFai Lau 12d8bb64e3 bpf: xdp: Add XDP example for head adjustment
The XDP prog checks if the incoming packet matches any VIP:PORT
combination in the BPF hashmap.  If it is, it will encapsulate
the packet with a IPv4/v6 header as instructed by the value of
the BPF hashmap and then XDP_TX it out.

The VIP:PORT -> IP-Encap-Info can be specified by the cmd args
of the user prog.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-08 14:25:13 -05:00
Sargun Dhillon 9b474ecee5 samples, bpf: Add automated test for cgroup filter attachments
This patch adds the sample program test_cgrp2_attach2. This program is
similar to test_cgrp2_attach, but it performs automated testing of the
cgroupv2 BPF attached filters. It runs the following checks:
* Simple filter attachment
* Application of filters to child cgroups
* Overriding filters on child cgroups
	* Checking that this still works when the parent filter is removed

The filters that are used here are simply allow all / deny all filters, so
it isn't checking the actual functionality of the filters, but rather
the behaviour  around detachment / attachment. If net_cls is enabled,
this test will fail.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 16:07:52 -05:00
Sargun Dhillon 1a922fee66 samples, bpf: Refactor test_current_task_under_cgroup - separate out helpers
This patch modifies test_current_task_under_cgroup_user. The test has
several helpers around creating a temporary environment for cgroup
testing, and moving the current task around cgroups. This set of
helpers can then be used in other tests.

Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 16:07:11 -05:00
Alexei Starovoitov 69a9d09b22 samples/bpf: silence compiler warnings
silence some of the clang compiler warnings like:
include/linux/fs.h:2693:9: warning: comparison of unsigned enum expression < 0 is always false
arch/x86/include/asm/processor.h:491:30: warning: taking address of packed member 'sp0' of class or structure 'x86_hw_tss' may result in an unaligned pointer value
include/linux/cgroup-defs.h:326:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension
since they add too much noise to samples/bpf/ build.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 16:01:14 -05:00
David Ahern 554ae6e792 samples/bpf: add userspace example for prohibiting sockets
Add examples preventing a process in a cgroup from opening a socket
based family, protocol and type.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 13:46:09 -05:00
David Ahern ad2805dc79 samples: bpf: add userspace example for modifying sk_bound_dev_if
Add a simple program to demonstrate the ability to attach a bpf program
to a cgroup that sets sk_bound_dev_if for AF_INET{6} sockets when they
are created.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 13:46:08 -05:00
Thomas Graf f74599f7c5 bpf: Add tests and samples for LWT-BPF
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: Thomas Graf <tgraf@suug.ch>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 10:52:00 -05:00
Alexei Starovoitov 9bee294f53 samples/bpf: fix include path
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: e00c7b216f ("bpf: fix multiple issues in selftest suite and samples")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 12:42:28 -05:00
Daniel Borkmann e00c7b216f bpf: fix multiple issues in selftest suite and samples
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: 3059303f59 ("samples/bpf: update tracex[23] examples to use per-cpu maps")
Fixes: 86af8b4191 ("Add sample for adding simple drop program to link")
Fixes: df570f5772 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_ARRAY")
Fixes: e155967179 ("samples/bpf: unit test for BPF_MAP_TYPE_PERCPU_HASH")
Fixes: ebb676daa1 ("bpf: Print function name in addition to function id")
Fixes: 5db58faf98 ("bpf: Add tests for the LRU bpf_htab")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: William Tu <u9012063@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
Daniel Mack d8c5b17f2b samples: bpf: add userspace example for attaching eBPF programs to cgroups
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: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:26:04 -05:00
Martin KaFai Lau 5db58faf98 bpf: Add tests for the LRU bpf_htab
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: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:43 -05:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
Martin KaFai Lau 90e02896f1 bpf: Add test for bpf_redirect to ipip/ip6tnl
The test creates two netns, ns1 and ns2.  The host (the default netns)
has an ipip or ip6tnl dev configured for tunneling traffic to the ns2.

    ping VIPS from ns1 <----> host <--tunnel--> ns2 (VIPs at loopback)

The test is to have ns1 pinging VIPs configured at the loopback
interface in ns2.

The VIPs are 10.10.1.102 and 2401:face::66 (which are configured
at lo@ns2). [Note: 0x66 => 102].

At ns1, the VIPs are routed _via_ the host.

At the host, bpf programs are installed at the veth to redirect packets
from a veth to the ipip/ip6tnl.  The test is configured in a way so
that both ingress and egress can be tested.

At ns2, the ipip/ip6tnl dev is configured with the local and remote address
specified.  The return path is routed to the dev ipip/ip6tnl.

During egress test, the host also locally tests pinging the VIPs to ensure
that bpf_redirect at egress also works for the direct egress (i.e. not
forwarding from dev ve1 to ve2).

Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-12 23:38:07 -05:00
Daniel Borkmann 5aa5bd14c5 bpf: add initial suite for selftests
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: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-18 11:35:55 -04:00
Brendan Gregg 72874418e4 samples/bpf: add sampleip example
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>
2016-09-02 10:46:45 -07:00
Alexei Starovoitov 1c47910ef8 samples/bpf: add perf_event+bpf example
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>
2016-09-02 10:46:45 -07:00
William Tu 6afb1e28b8 samples/bpf: Add tunnel set/get tests.
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>
2016-08-19 22:42:44 -07:00
Sargun Dhillon 9e6e60ecbd samples/bpf: Add test_current_task_under_cgroup test
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>
2016-08-12 21:49:42 -07:00
Sargun Dhillon cf9b1199de samples/bpf: Add test/example of using bpf_probe_write_user bpf helper
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>
2016-07-25 18:07:48 -07:00
Brenden Blanco 764cbccef8 bpf: add sample for xdp forwarding and rewrite
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>
2016-07-19 21:46:33 -07:00
Brenden Blanco 86af8b4191 Add sample for adding simple drop program to link
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>
2016-07-19 21:46:32 -07:00
Martin KaFai Lau a3f7461734 cgroup: bpf: Add an example to do cgroup checking in BPF
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>
2016-07-01 16:32:13 -04:00
Alexei Starovoitov 65d472fb00 samples/bpf: add 'pointer to packet' tests
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>
2016-05-06 16:01:54 -04:00
Jesper Dangaard Brouer bdefbbf2ec samples/bpf: like LLC also verify and allow redefining CLANG command
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>
2016-04-29 14:26:08 -04:00
Jesper Dangaard Brouer b62a796c10 samples/bpf: allow make to be run from samples/bpf/ directory
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>
2016-04-29 14:25:33 -04:00
Jesper Dangaard Brouer 7b01dd5793 samples/bpf: Makefile verify LLVM compiler avail and bpf target is supported
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>
2016-04-29 14:25:32 -04:00
Jesper Dangaard Brouer 6ccfba75d3 samples/bpf: add back functionality to redefine LLC command
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 128d1514be ("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: 128d1514be ("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>
2016-04-29 14:25:32 -04:00
David S. Miller ae95d71261 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-04-09 17:41:41 -04:00
Alexei Starovoitov e3edfdec04 samples/bpf: add tracepoint vs kprobe performance tests
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>
2016-04-07 21:04:27 -04:00
Naveen N. Rao 128d1514be samples/bpf: Use llc in PATH, rather than a hardcoded value
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>
2016-04-06 16:01:28 -04:00
Alexei Starovoitov 26e9093110 samples/bpf: add map performance test
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>
2016-03-08 23:22:03 -05:00
Alexei Starovoitov 9d8b612d88 samples/bpf: add bpf map stress test
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>
2016-03-08 23:22:02 -05:00
Alexei Starovoitov a6ffe7b9df samples/bpf: offwaketime example
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>
2016-02-20 00:21:44 -05:00
Yang Shi 30b50aa612 bpf: samples: exclude asm/sysreg.h for arm64
commit 338d4f49d6
("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>
2015-11-16 14:40:49 -05:00
Daniel Borkmann 42984d7c1e bpf: add sample usages for persistent maps/progs
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>
2015-11-02 22:48:39 -05:00