Macro PAGE_OFFSET(0xffff880000000000) in sampleip_user.c is inaccurate,
for example, in aarch64 architecture, this value depends on the
CONFIG_ARM64_VA_BITS compilation configuration, this value defaults to 48,
the corresponding PAGE_OFFSET is 0xffff800000000000, if we use the value
defined in sampleip_user.c, then all KSYMs obtained by sampleip are (user)
Symbol error due to PAGE_OFFSET error:
$ sudo ./sampleip 1
Sampling at 99 Hertz for 1 seconds. Ctrl-C also ends.
ADDR KSYM COUNT
0xffff80000810ceb8 (user) 1
0xffffb28ec880 (user) 1
0xffff8000080c82b8 (user) 1
0xffffb23fed24 (user) 1
0xffffb28944fc (user) 1
0xffff8000084628bc (user) 1
0xffffb2a935c0 (user) 1
0xffff80000844677c (user) 1
0xffff80000857a3a4 (user) 1
...
A few examples of addresses in the CONFIG_ARM64_VA_BITS=48 environment in
the aarch64 environment:
$ sudo head /proc/kallsyms
ffff8000080a0000 T _text
ffff8000080b0000 t gic_handle_irq
ffff8000080b0000 T _stext
ffff8000080b0000 T __irqentry_text_start
ffff8000080b00b0 t gic_handle_irq
ffff8000080b0230 t gic_handle_irq
ffff8000080b03b4 T __irqentry_text_end
ffff8000080b03b8 T __softirqentry_text_start
ffff8000080b03c0 T __do_softirq
ffff8000080b0718 T __entry_text_start
We just need to replace the PAGE_OFFSET with the address _text in
/proc/kallsyms to solve this problem:
$ sudo ./sampleip 1
Sampling at 99 Hertz for 1 seconds. Ctrl-C also ends.
ADDR KSYM COUNT
0xffffb2892ab0 (user) 1
0xffffb2b1edfc (user) 1
0xffff800008462834 __arm64_sys_ppoll 1
0xffff8000084b87f4 eventfd_read 1
0xffffb28e6788 (user) 1
0xffff8000081e96d8 rcu_all_qs 1
0xffffb2ada878 (user) 1
...
Signed-off-by: Rong Tao <rongtao@cestc.cn>
Link: https://lore.kernel.org/r/tencent_A0E82E0BEE925285F8156D540731DF805F05@qq.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Current method of checking pointer error is not user friendly.
Especially the __must_check define makes this less intuitive.
Since, libbpf has an API libbpf_get_error() which checks pointer error,
this commit refactors existing pointer error check logic with libbpf.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200516040608.1377876-2-danieltimlee@gmail.com
The bpf_program__attach of libbpf(using bpf_link) is much more intuitive
than the previous method using ioctl.
bpf_program__attach_perf_event manages the enable of perf_event and
attach of BPF programs to it, so there's no neeed to do this
directly with ioctl.
In addition, bpf_link provides consistency in the use of API because it
allows disable (detach, destroy) for multiple events to be treated as
one bpf_link__destroy. Also, bpf_link__destroy manages the close() of
perf_event fd.
This commit refactors samples that attach the bpf program to perf_event
by using libbbpf instead of ioctl. Also the bpf_load in the samples were
removed and migrated to use libbbpf API.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200321100424.1593964-3-danieltimlee@gmail.com
Fix all files in samples/bpf to include libbpf header files with the bpf/
prefix, to be consistent with external users of the library. Also ensure
that all includes of exported libbpf header files (those that are exported
on 'make install' of the library) use bracketed includes instead of quoted.
To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.
Fixes: 6910d7d386 ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560911.1683545.8795966751309534150.stgit@toke.dk
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 107 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since, ksym_search added with verification logic for symbols existence,
it could return NULL when the kernel symbols are not loaded.
This commit will add NULL check logic after ksym_search.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
There is no functionality change in this patch. The common-purpose
trace functions, including perf_event polling and ksym lookup,
are moved from trace_output_user.c and bpf_load.c to
selftests/bpf/trace_helpers.c so that these function can
be reused later in selftests.
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Shahid Habib noticed that when xdp1 was killed from a different console the xdp
program was not cleaned-up properly in the kernel and it continued to forward
traffic.
Most of the applications in samples/bpf cleanup properly, but only when getting
SIGINT. Since kill defaults to using SIGTERM, add support to cleanup when the
application receives either SIGINT or SIGTERM.
Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Reported-by: Shahid Habib <shahid.habib@broadcom.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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: 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: http://lkml.kernel.org/r/20161214224342.12858-2-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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>
