Do this change before others start to use this callback.
Change map_perf_test_user.c which seems to be the only user.

This patch extends capabilities of commit 9fd63d05 ("bpf:
Allow bpf sample programs (*_user.c) to change bpf_map_def").

Give fixup callback access to struct bpf_map_data, instead of
only stuct bpf_map_def.  This add flexibility to allow userspace
to reassign the map file descriptor.  This is very useful when
wanting to share maps between several bpf programs.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch does proper parsing of the ELF "maps" section, in-order to
be both backwards and forwards compatible with changes to the map
definition struct bpf_map_def, which gets compiled into the ELF file.

The assumption is that new features with value zero, means that they
are not in-use.  For backward compatibility where loading an ELF file
with a smaller struct bpf_map_def, only copy objects ELF size, leaving
rest of loaders struct zero.  For forward compatibility where ELF file
have a larger struct bpf_map_def, only copy loaders own struct size
and verify that rest of the larger struct is zero, assuming this means
the newer feature was not activated, thus it should be safe for this
older loader to load this newer ELF file.

Fixes: fb30d4b7 ("bpf: Add tests for map-in-map")
Fixes: 409526bea3c3 ("samples/bpf: bpf_load.c detect and abort if ELF maps section size is wrong")
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kernel side of XDP_FLAGS_SKB_MODE is unsigned, and the rtnetlink
IFLA_XDP_FLAGS is defined as NLA_U32. Thus, userspace programs under
samples/bpf/ should use the correct type.

Fixes: 3993f2cb ("samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel")
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NAndy Gospodarek <andy@greyhouse.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The struct bpf_map_def was extended in commit fb30d4b7 ("bpf: Add tests
for map-in-map") with member unsigned int inner_map_idx.  This changed the size
of the maps section in the generated ELF _kern.o files.

Unfortunately the loader in bpf_load.c does not detect or handle this.  Thus,
older _kern.o files became incompatible, and caused hard-to-debug errors
where the syscall validation rejected BPF_MAP_CREATE request.

This patch only detect the situation and aborts load_bpf_file(). It also
add code comments warning people that read this loader for inspiration
for these pitfalls.

Fixes: fb30d4b7 ("bpf: Add tests for map-in-map")
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add option to xdp1 and xdp_tx_iptunnel to insert xdp program in
SKB_MODE:
 - update set_link_xdp_fd to take a flags argument that is added to the
   RTM_SETLINK message

 - Add -S option to xdp1 and xdp_tx_iptunnel user code. When passed in
   XDP_FLAGS_SKB_MODE is set in the flags arg passed to set_link_xdp_fd
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current bpf_map_def is statically defined during compile
time.  This patch allows the *_user.c program to change it during
runtime.  It is done by adding load_bpf_file_fixup_map() which
takes a callback.  The callback will be called before creating
each map so that it has a chance to modify the bpf_map_def.

The current usecase is to change max_entries in map_perf_test.
It is interesting to test with a much bigger map size in
some cases (e.g. the following patch on bpf_lru_map.c).
However,  it is hard to find one size to fit all testing
environment.  Hence, it is handy to take the max_entries
as a cmdline arg and then configure the bpf_map_def during
runtime.

This patch adds two cmdline args.  One is to configure
the map's max_entries.  Another is to configure the max_cnt
which controls how many times a syscall is called.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Test cases for array of maps and hash of maps.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before loading a new ELF, clean previous kernel version, license and
processed sections.
Signed-off-by: NMickaël Salaün <mic@digikod.net>
Acked-by: NJoe Stringer <joe@ovn.org>
Acked-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170208202744.16274-3-mic@digikod.netSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Add a missing check for the map fixup loop.
Signed-off-by: NMickaël Salaün <mic@digikod.net>
Acked-by: NJoe Stringer <joe@ovn.org>
Acked-by: NWang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170208202744.16274-2-mic@digikod.netSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

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: NJoe Stringer <joe@ovn.org>
Tested-by: NArnaldo 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: NArnaldo Carvalho de Melo <acme@redhat.com>

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: NJoe Stringer <joe@ovn.org>
Tested-by: NArnaldo 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: https://github.com/joestringer/linux/commit/5c40f54a52b1f437123c81e21873f4b4b1f9bd55.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: NArnaldo Carvalho de Melo <acme@redhat.com>

Switch all of the sample code to use the function names from
tools/lib/bpf so that they're consistent with that, and to declare their
own log buffers. This allow the next commit to be purely devoted to
getting rid of the duplicate library in samples/bpf.

Committer notes:

Testing it:

On a fedora rawhide container, with clang/llvm 3.9, sharing the host
linux kernel git tree:

  # make O=/tmp/build/linux/ headers_install
  # make O=/tmp/build/linux -C samples/bpf/

Since I forgot to make it privileged, just tested it outside the
container, using what it generated:

  # uname -a
  Linux jouet 4.9.0-rc8+ #1 SMP Mon Dec 12 11:20:49 BRT 2016 x86_64 x86_64 x86_64 GNU/Linux
  # cd /var/lib/docker/devicemapper/mnt/c43e09a53ff56c86a07baf79847f00e2cc2a17a1e2220e1adbf8cbc62734feda/rootfs/tmp/build/linux/samples/bpf/
  # ls -la offwaketime
  -rwxr-xr-x. 1 root root 24200 Dec 15 12:19 offwaketime
  # 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]=c940d3f127d5e66cdd680e42d885cb0b64f8a0e4, not stripped
  # readelf -SW offwaketime_kern.o  | grep PROGBITS
  [ 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
  [ 5] tracepoint/sched/sched_switch PROGBITS        0000000000000000 000118 000318 00  AX  0   0  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
  # ./offwaketime | head -5
  swapper/1;start_secondary;cpu_startup_entry;schedule_preempt_disabled;schedule;__schedule;-;---;; 106
  CPU 0/KVM;entry_SYSCALL_64_fastpath;sys_ioctl;do_vfs_ioctl;kvm_vcpu_ioctl;kvm_arch_vcpu_ioctl_run;kvm_vcpu_block;schedule;__schedule;-;try_to_wake_up;swake_up_locked;swake_up;apic_timer_expired;apic_timer_fn;__hrtimer_run_queues;hrtimer_interrupt;local_apic_timer_interrupt;smp_apic_timer_interrupt;__irqentry_text_start;cpuidle_enter;call_cpuidle;cpu_startup_entry;start_secondary;;swapper/3 2
  Compositor;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;futex_requeue;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;SoftwareVsyncTh 5
  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 13
  JS Helper;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;firefox 2
  #
Signed-off-by: NJoe Stringer <joe@ovn.org>
Tested-by: NArnaldo 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: http://lkml.kernel.org/r/20161214224342.12858-2-joe@ovn.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

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: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for section names starting with cgroup/skb and cgroup/sock.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

llvm can emit relocations into sections other than program code
(like debug info sections). Ignore them during parsing of elf file
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Add a sample program that only drops packets at the BPF_PROG_TYPE_XDP_RX
hook of a link. With the drop-only program, observed single core rate is
~20Mpps.

Other tests were run, for instance without the dropcnt increment or
without reading from the packet header, the packet rate was mostly
unchanged.

$ perf record -a samples/bpf/xdp1 $(</sys/class/net/eth0/ifindex)
proto 17:   20403027 drops/s

./pktgen_sample03_burst_single_flow.sh -i $DEV -d $IP -m $MAC -t 4
Running... ctrl^C to stop
Device: eth4@0
Result: OK: 11791017(c11788327+d2689) usec, 59622913 (60byte,0frags)
  5056638pps 2427Mb/sec (2427186240bps) errors: 0
Device: eth4@1
Result: OK: 11791012(c11787906+d3106) usec, 60526944 (60byte,0frags)
  5133311pps 2463Mb/sec (2463989280bps) errors: 0
Device: eth4@2
Result: OK: 11791019(c11788249+d2769) usec, 59868091 (60byte,0frags)
  5077431pps 2437Mb/sec (2437166880bps) errors: 0
Device: eth4@3
Result: OK: 11795039(c11792403+d2636) usec, 59483181 (60byte,0frags)
  5043067pps 2420Mb/sec (2420672160bps) errors: 0

perf report --no-children:
 26.05%  ksoftirqd/0  [mlx4_en]         [k] mlx4_en_process_rx_cq
 17.84%  ksoftirqd/0  [mlx4_en]         [k] mlx4_en_alloc_frags
  5.52%  ksoftirqd/0  [mlx4_en]         [k] mlx4_en_free_frag
  4.90%  swapper      [kernel.vmlinux]  [k] poll_idle
  4.14%  ksoftirqd/0  [kernel.vmlinux]  [k] get_page_from_freelist
  2.78%  ksoftirqd/0  [kernel.vmlinux]  [k] __free_pages_ok
  2.57%  ksoftirqd/0  [kernel.vmlinux]  [k] bpf_map_lookup_elem
  2.51%  swapper      [mlx4_en]         [k] mlx4_en_process_rx_cq
  1.94%  ksoftirqd/0  [kernel.vmlinux]  [k] percpu_array_map_lookup_elem
  1.45%  swapper      [mlx4_en]         [k] mlx4_en_alloc_frags
  1.35%  ksoftirqd/0  [kernel.vmlinux]  [k] free_one_page
  1.33%  swapper      [kernel.vmlinux]  [k] intel_idle
  1.04%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c5c5
  0.96%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c58d
  0.93%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c6ee
  0.92%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c6b9
  0.89%  ksoftirqd/0  [kernel.vmlinux]  [k] __alloc_pages_nodemask
  0.83%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c686
  0.83%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c5d5
  0.78%  ksoftirqd/0  [mlx4_en]         [k] mlx4_alloc_pages.isra.23
  0.77%  ksoftirqd/0  [mlx4_en]         [k] 0x000000000001c5b4
  0.77%  ksoftirqd/0  [kernel.vmlinux]  [k] net_rx_action

machine specs:
 receiver - Intel E5-1630 v3 @ 3.70GHz
 sender - Intel E5645 @ 2.40GHz
 Mellanox ConnectX-3 @40G
Signed-off-by: NBrenden Blanco <bblanco@plumgrid.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Recognize "tracepoint/" section name prefix and attach the program
to that tracepoint.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

note old loader is compatible with new kernel.
map_flags are optional
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

move ksym search from offwaketime into library to be reused
in other tests
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

kprobe example that demonstrates how future seccomp programs may look like.
It attaches to seccomp_phase1() function and tail-calls other BPF programs
depending on syscall number.

Existing optimized classic BPF seccomp programs generated by Chrome look like:
if (sd.nr < 121) {
  if (sd.nr < 57) {
    if (sd.nr < 22) {
      if (sd.nr < 7) {
        if (sd.nr < 4) {
          if (sd.nr < 1) {
            check sys_read
          } else {
            if (sd.nr < 3) {
              check sys_write and sys_open
            } else {
              check sys_close
            }
          }
        } else {
      } else {
    } else {
  } else {
} else {
}

the future seccomp using native eBPF may look like:
  bpf_tail_call(&sd, &syscall_jmp_table, sd.nr);
which is simpler, faster and leaves more room for per-syscall checks.

Usage:
$ sudo ./tracex5
<...>-366   [001] d...     4.870033: : read(fd=1, buf=00007f6d5bebf000, size=771)
<...>-369   [003] d...     4.870066: : mmap
<...>-369   [003] d...     4.870077: : syscall=110 (one of get/set uid/pid/gid)
<...>-369   [003] d...     4.870089: : syscall=107 (one of get/set uid/pid/gid)
   sh-369   [000] d...     4.891740: : read(fd=0, buf=00000000023d1000, size=512)
   sh-369   [000] d...     4.891747: : write(fd=1, buf=00000000023d3000, size=512)
   sh-369   [000] d...     4.891747: : read(fd=1, buf=00000000023d3000, size=512)
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tracex1_kern.c - C program compiled into BPF.

It attaches to kprobe:netif_receive_skb()

When skb->dev->name == "lo", it prints sample debug message into
trace_pipe via bpf_trace_printk() helper function.

tracex1_user.c - corresponding user space component that:
  - loads BPF program via bpf() syscall
  - opens kprobes:netif_receive_skb event via perf_event_open()
    syscall
  - attaches the program to event via ioctl(event_fd,
    PERF_EVENT_IOC_SET_BPF, prog_fd);
  - prints from trace_pipe

Note, this BPF program is non-portable. It must be recompiled
with current kernel headers. kprobe is not a stable ABI and
BPF+kprobe scripts may no longer be meaningful when kernel
internals change.

No matter in what way the kernel changes, neither the kprobe,
nor the BPF program can ever crash or corrupt the kernel,
assuming the kprobes, perf and BPF subsystem has no bugs.

The verifier will detect that the program is using
bpf_trace_printk() and the kernel will print 'this is a DEBUG
kernel' warning banner, which means that bpf_trace_printk()
should be used for debugging of the BPF program only.

Usage:
$ sudo tracex1
            ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84
            ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84

            ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84
            ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

simple .o parser and loader using BPF syscall.
.o is a standard ELF generated by LLVM backend

It parses elf file compiled by llvm .c->.o
- parses 'maps' section and creates maps via BPF syscall
- parses 'license' section and passes it to syscall
- parses elf relocations for BPF maps and adjusts BPF_LD_IMM64 insns
  by storing map_fd into insn->imm and marking such insns as BPF_PSEUDO_MAP_FD
- loads eBPF programs via BPF syscall

One ELF file can contain multiple BPF programs.

int load_bpf_file(char *path);
populates prog_fd[] and map_fd[] with FDs received from bpf syscall

bpf_helpers.h - helper functions available to eBPF programs written in C
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>