samples/bpf: Make samples more libbpf-centric

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>

1 files changed, 13 insertions, 4 deletions

diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index e30b6de94f2e..f5b186c46b7c 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -22,7 +22,6 @@
 #include <poll.h>
 #include <ctype.h>
 #include "libbpf.h"
-#include "bpf_helpers.h"
 #include "bpf_load.h"
 
 #define DEBUGFS "/sys/kernel/debug/tracing/"
@@ -30,17 +29,26 @@
 static char license[128];
 static int kern_version;
 static bool processed_sec[128];
+char bpf_log_buf[BPF_LOG_BUF_SIZE];
 int map_fd[MAX_MAPS];
 int prog_fd[MAX_PROGS];
 int event_fd[MAX_PROGS];
 int prog_cnt;
 int prog_array_fd = -1;
 
+struct bpf_map_def {
+	unsigned int type;
+	unsigned int key_size;
+	unsigned int value_size;
+	unsigned int max_entries;
+	unsigned int map_flags;
+};
+
 static int populate_prog_array(const char *event, int prog_fd)
 {
 	int ind = atoi(event), err;
 
-	err = bpf_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
+	err = bpf_map_update_elem(prog_array_fd, &ind, &prog_fd, BPF_ANY);
 	if (err < 0) {
 		printf("failed to store prog_fd in prog_array\n");
 		return -1;
@@ -87,9 +95,10 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
 		return -1;
 	}
 
-	fd = bpf_prog_load(prog_type, prog, size, license, kern_version);
+	fd = bpf_load_program(prog_type, prog, size, license, kern_version,
+			      bpf_log_buf, BPF_LOG_BUF_SIZE);
 	if (fd < 0) {
-		printf("bpf_prog_load() err=%d\n%s", errno, bpf_log_buf);
+		printf("bpf_load_program() err=%d\n%s", errno, bpf_log_buf);
 		return -1;
 	}