[PATCH bpf-next 0/4] samples: bpf: fix build after move to full libbpf

[PATCH bpf-next 0/4] samples: bpf: fix build after move to full libbpf

[Jakub Kicinski]

Hi!

Following patches address build issues after recent move to libbpf.
For out-of-tree builds we would see the following error:

gcc: error: samples/bpf/../../tools/lib/bpf/libbpf.a: No such file or directory

Mini-library called libbpf.h in samples is renamed to bpf_insn.h,
using linux/filter.h seems not completely trivial since some samples
get upset when order on include search path in changed.  We do have
to rename libbpf.h, however, because otherwise it's hard to reliably
get to libbpf's header in out-of-tree builds.

Jakub Kicinski (4):
  samples: bpf: include bpf/bpf.h instead of local libbpf.h
  samples: bpf: rename libbpf.h to bpf_insn.h
  samples: bpf: fix build after move to compiling full libbpf.a
  samples: bpf: move libbpf from object dependencies to libs

 samples/bpf/Makefile                          | 170 +++++++-----------
 samples/bpf/{libbpf.h => bpf_insn.h}          |   8 +-
 samples/bpf/bpf_load.c                        |   2 +-
 samples/bpf/bpf_load.h                        |   2 +-
 samples/bpf/cookie_uid_helper_example.c       |   2 +-
 samples/bpf/cpustat_user.c                    |   2 +-
 samples/bpf/fds_example.c                     |   4 +-
 samples/bpf/lathist_user.c                    |   2 +-
 samples/bpf/load_sock_ops.c                   |   2 +-
 samples/bpf/lwt_len_hist_user.c               |   2 +-
 samples/bpf/map_perf_test_user.c              |   2 +-
 samples/bpf/sock_example.c                    |   3 +-
 samples/bpf/sock_example.h                    |   1 -
 samples/bpf/sockex1_user.c                    |   2 +-
 samples/bpf/sockex2_user.c                    |   2 +-
 samples/bpf/sockex3_user.c                    |   2 +-
 samples/bpf/syscall_tp_user.c                 |   2 +-
 samples/bpf/tc_l2_redirect_user.c             |   2 +-
 samples/bpf/test_cgrp2_array_pin.c            |   2 +-
 samples/bpf/test_cgrp2_attach.c               |   3 +-
 samples/bpf/test_cgrp2_attach2.c              |   3 +-
 samples/bpf/test_cgrp2_sock.c                 |   3 +-
 samples/bpf/test_cgrp2_sock2.c                |   3 +-
 .../bpf/test_current_task_under_cgroup_user.c |   2 +-
 samples/bpf/test_lru_dist.c                   |   2 +-
 samples/bpf/test_map_in_map_user.c            |   2 +-
 samples/bpf/test_overhead_user.c              |   2 +-
 samples/bpf/test_probe_write_user_user.c      |   2 +-
 samples/bpf/trace_output_user.c               |   2 +-
 samples/bpf/tracex1_user.c                    |   2 +-
 samples/bpf/tracex2_user.c                    |   2 +-
 samples/bpf/tracex3_user.c                    |   2 +-
 samples/bpf/tracex4_user.c                    |   2 +-
 samples/bpf/tracex5_user.c                    |   2 +-
 samples/bpf/tracex6_user.c                    |   2 +-
 samples/bpf/tracex7_user.c                    |   2 +-
 samples/bpf/xdp_fwd_user.c                    |   2 +-
 samples/bpf/xdp_monitor_user.c                |   2 +-
 samples/bpf/xdp_redirect_cpu_user.c           |   2 +-
 samples/bpf/xdp_redirect_map_user.c           |   2 +-
 samples/bpf/xdp_redirect_user.c               |   2 +-
 samples/bpf/xdp_router_ipv4_user.c            |   2 +-
 samples/bpf/xdp_tx_iptunnel_user.c            |   2 +-
 samples/bpf/xdpsock_user.c                    |   2 +-
 44 files changed, 117 insertions(+), 151 deletions(-)
 rename samples/bpf/{libbpf.h => bpf_insn.h} (98%)

-- 
2.17.0

[PATCH bpf-next 1/4] samples: bpf: include bpf/bpf.h instead of local libbpf.h

[Jakub Kicinski]

There are two files in the tree called libbpf.h which is becoming
problematic.  Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h.  Include bpf/bpf.h
directly instead.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 samples/bpf/bpf_load.c                            | 2 +-
 samples/bpf/bpf_load.h                            | 2 +-
 samples/bpf/cpustat_user.c                        | 2 +-
 samples/bpf/lathist_user.c                        | 2 +-
 samples/bpf/load_sock_ops.c                       | 2 +-
 samples/bpf/lwt_len_hist_user.c                   | 2 +-
 samples/bpf/map_perf_test_user.c                  | 2 +-
 samples/bpf/sock_example.h                        | 1 -
 samples/bpf/sockex1_user.c                        | 2 +-
 samples/bpf/sockex2_user.c                        | 2 +-
 samples/bpf/sockex3_user.c                        | 2 +-
 samples/bpf/syscall_tp_user.c                     | 2 +-
 samples/bpf/tc_l2_redirect_user.c                 | 2 +-
 samples/bpf/test_cgrp2_array_pin.c                | 2 +-
 samples/bpf/test_current_task_under_cgroup_user.c | 2 +-
 samples/bpf/test_lru_dist.c                       | 2 +-
 samples/bpf/test_map_in_map_user.c                | 2 +-
 samples/bpf/test_overhead_user.c                  | 2 +-
 samples/bpf/test_probe_write_user_user.c          | 2 +-
 samples/bpf/trace_output_user.c                   | 2 +-
 samples/bpf/tracex1_user.c                        | 2 +-
 samples/bpf/tracex2_user.c                        | 2 +-
 samples/bpf/tracex3_user.c                        | 2 +-
 samples/bpf/tracex4_user.c                        | 2 +-
 samples/bpf/tracex5_user.c                        | 2 +-
 samples/bpf/tracex6_user.c                        | 2 +-
 samples/bpf/tracex7_user.c                        | 2 +-
 samples/bpf/xdp_fwd_user.c                        | 2 +-
 samples/bpf/xdp_monitor_user.c                    | 2 +-
 samples/bpf/xdp_redirect_cpu_user.c               | 2 +-
 samples/bpf/xdp_redirect_map_user.c               | 2 +-
 samples/bpf/xdp_redirect_user.c                   | 2 +-
 samples/bpf/xdp_router_ipv4_user.c                | 2 +-
 samples/bpf/xdp_tx_iptunnel_user.c                | 2 +-
 samples/bpf/xdpsock_user.c                        | 2 +-
 35 files changed, 34 insertions(+), 35 deletions(-)

diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index a6b290de5632..89161c9ed466 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -24,7 +24,7 @@
 #include <poll.h>
 #include <ctype.h>
 #include <assert.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "perf-sys.h"
 
diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index f9da59bca0cc..814894a12974 100644
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -2,7 +2,7 @@
 #ifndef __BPF_LOAD_H
 #define __BPF_LOAD_H
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 #define MAX_MAPS 32
 #define MAX_PROGS 32
diff --git a/samples/bpf/cpustat_user.c b/samples/bpf/cpustat_user.c
index 2b4cd1ae57c5..869a99406dbf 100644
--- a/samples/bpf/cpustat_user.c
+++ b/samples/bpf/cpustat_user.c
@@ -17,7 +17,7 @@
 #include <sys/resource.h>
 #include <sys/wait.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #define MAX_CPU			8
diff --git a/samples/bpf/lathist_user.c b/samples/bpf/lathist_user.c
index 6477bad5b4e2..c8e88cc84e61 100644
--- a/samples/bpf/lathist_user.c
+++ b/samples/bpf/lathist_user.c
@@ -10,7 +10,7 @@
 #include <stdlib.h>
 #include <signal.h>
 #include <linux/bpf.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #define MAX_ENTRIES	20
diff --git a/samples/bpf/load_sock_ops.c b/samples/bpf/load_sock_ops.c
index e5da6cf71a3e..8ecb41ea0c03 100644
--- a/samples/bpf/load_sock_ops.c
+++ b/samples/bpf/load_sock_ops.c
@@ -8,7 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <linux/bpf.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include <unistd.h>
 #include <errno.h>
diff --git a/samples/bpf/lwt_len_hist_user.c b/samples/bpf/lwt_len_hist_user.c
index 7fcb94c09112..587b68b1f8dd 100644
--- a/samples/bpf/lwt_len_hist_user.c
+++ b/samples/bpf/lwt_len_hist_user.c
@@ -9,7 +9,7 @@
 #include <errno.h>
 #include <arpa/inet.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_util.h"
 
 #define MAX_INDEX 64
diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
index 519d9af4b04a..38b7b1a96cc2 100644
--- a/samples/bpf/map_perf_test_user.c
+++ b/samples/bpf/map_perf_test_user.c
@@ -21,7 +21,7 @@
 #include <arpa/inet.h>
 #include <errno.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #define TEST_BIT(t) (1U << (t))
diff --git a/samples/bpf/sock_example.h b/samples/bpf/sock_example.h
index 772d5dad8465..a27d7579bc73 100644
--- a/samples/bpf/sock_example.h
+++ b/samples/bpf/sock_example.h
@@ -9,7 +9,6 @@
 #include <net/if.h>
 #include <linux/if_packet.h>
 #include <arpa/inet.h>
-#include "libbpf.h"
 
 static inline int open_raw_sock(const char *name)
 {
diff --git a/samples/bpf/sockex1_user.c b/samples/bpf/sockex1_user.c
index 2be935c2627d..93ec01c56104 100644
--- a/samples/bpf/sockex1_user.c
+++ b/samples/bpf/sockex1_user.c
@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <assert.h>
 #include <linux/bpf.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "sock_example.h"
 #include <unistd.h>
diff --git a/samples/bpf/sockex2_user.c b/samples/bpf/sockex2_user.c
index 44fe0805b087..1d5c6e9a6d27 100644
--- a/samples/bpf/sockex2_user.c
+++ b/samples/bpf/sockex2_user.c
@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <assert.h>
 #include <linux/bpf.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "sock_example.h"
 #include <unistd.h>
diff --git a/samples/bpf/sockex3_user.c b/samples/bpf/sockex3_user.c
index 495ee02e2fb7..5ba3ae9d180b 100644
--- a/samples/bpf/sockex3_user.c
+++ b/samples/bpf/sockex3_user.c
@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <assert.h>
 #include <linux/bpf.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "sock_example.h"
 #include <unistd.h>
diff --git a/samples/bpf/syscall_tp_user.c b/samples/bpf/syscall_tp_user.c
index 9169d3207f18..1a1d0059a277 100644
--- a/samples/bpf/syscall_tp_user.c
+++ b/samples/bpf/syscall_tp_user.c
@@ -16,7 +16,7 @@
 #include <assert.h>
 #include <stdbool.h>
 #include <sys/resource.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 /* This program verifies bpf attachment to tracepoint sys_enter_* and sys_exit_*.
diff --git a/samples/bpf/tc_l2_redirect_user.c b/samples/bpf/tc_l2_redirect_user.c
index 28995a776560..7ec45c3e8f56 100644
--- a/samples/bpf/tc_l2_redirect_user.c
+++ b/samples/bpf/tc_l2_redirect_user.c
@@ -13,7 +13,7 @@
 #include <string.h>
 #include <errno.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 static void usage(void)
 {
diff --git a/samples/bpf/test_cgrp2_array_pin.c b/samples/bpf/test_cgrp2_array_pin.c
index 8a1b8b5d8def..242184292f59 100644
--- a/samples/bpf/test_cgrp2_array_pin.c
+++ b/samples/bpf/test_cgrp2_array_pin.c
@@ -14,7 +14,7 @@
 #include <errno.h>
 #include <fcntl.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 static void usage(void)
 {
diff --git a/samples/bpf/test_current_task_under_cgroup_user.c b/samples/bpf/test_current_task_under_cgroup_user.c
index 65b5fb51c1db..4be4874ca2bc 100644
--- a/samples/bpf/test_current_task_under_cgroup_user.c
+++ b/samples/bpf/test_current_task_under_cgroup_user.c
@@ -9,7 +9,7 @@
 #include <stdio.h>
 #include <linux/bpf.h>
 #include <unistd.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include <linux/bpf.h>
 #include "cgroup_helpers.h"
diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index 73c357142268..eec3e2509ce8 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -21,7 +21,7 @@
 #include <stdlib.h>
 #include <time.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_util.h"
 
 #define min(a, b) ((a) < (b) ? (a) : (b))
diff --git a/samples/bpf/test_map_in_map_user.c b/samples/bpf/test_map_in_map_user.c
index 1aca18539d8d..e308858f7bcf 100644
--- a/samples/bpf/test_map_in_map_user.c
+++ b/samples/bpf/test_map_in_map_user.c
@@ -13,7 +13,7 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <stdio.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #define PORT_A		(map_fd[0])
diff --git a/samples/bpf/test_overhead_user.c b/samples/bpf/test_overhead_user.c
index e1d35e07a10e..6caf47afa635 100644
--- a/samples/bpf/test_overhead_user.c
+++ b/samples/bpf/test_overhead_user.c
@@ -19,7 +19,7 @@
 #include <string.h>
 #include <time.h>
 #include <sys/resource.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #define MAX_CNT 1000000
diff --git a/samples/bpf/test_probe_write_user_user.c b/samples/bpf/test_probe_write_user_user.c
index bf8e3a9f3067..045eb5e30f54 100644
--- a/samples/bpf/test_probe_write_user_user.c
+++ b/samples/bpf/test_probe_write_user_user.c
@@ -3,7 +3,7 @@
 #include <assert.h>
 #include <linux/bpf.h>
 #include <unistd.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include <sys/socket.h>
 #include <string.h>
diff --git a/samples/bpf/trace_output_user.c b/samples/bpf/trace_output_user.c
index da98be721001..4837d73edefe 100644
--- a/samples/bpf/trace_output_user.c
+++ b/samples/bpf/trace_output_user.c
@@ -18,7 +18,7 @@
 #include <sys/mman.h>
 #include <time.h>
 #include <signal.h>
-#include "libbpf.h"
+#include <libbpf.h>
 #include "bpf_load.h"
 #include "perf-sys.h"
 #include "trace_helpers.h"
diff --git a/samples/bpf/tracex1_user.c b/samples/bpf/tracex1_user.c
index 3dcb475fb135..af8c20608ab5 100644
--- a/samples/bpf/tracex1_user.c
+++ b/samples/bpf/tracex1_user.c
@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <linux/bpf.h>
 #include <unistd.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 int main(int ac, char **argv)
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
index efb5e61918df..1a81e6a5c2ea 100644
--- a/samples/bpf/tracex2_user.c
+++ b/samples/bpf/tracex2_user.c
@@ -7,7 +7,7 @@
 #include <string.h>
 #include <sys/resource.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "bpf_util.h"
 
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c
index fe372239d505..6c6b10f4c3ee 100644
--- a/samples/bpf/tracex3_user.c
+++ b/samples/bpf/tracex3_user.c
@@ -13,7 +13,7 @@
 #include <linux/bpf.h>
 #include <sys/resource.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "bpf_util.h"
 
diff --git a/samples/bpf/tracex4_user.c b/samples/bpf/tracex4_user.c
index 22c644f1f4c3..14625c898e43 100644
--- a/samples/bpf/tracex4_user.c
+++ b/samples/bpf/tracex4_user.c
@@ -14,7 +14,7 @@
 #include <linux/bpf.h>
 #include <sys/resource.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 struct pair {
diff --git a/samples/bpf/tracex5_user.c b/samples/bpf/tracex5_user.c
index 4e2774b731f0..c4ab91c89494 100644
--- a/samples/bpf/tracex5_user.c
+++ b/samples/bpf/tracex5_user.c
@@ -5,7 +5,7 @@
 #include <linux/filter.h>
 #include <linux/seccomp.h>
 #include <sys/prctl.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include <sys/resource.h>
 
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
index 89ab8d408474..4bb3c830adb2 100644
--- a/samples/bpf/tracex6_user.c
+++ b/samples/bpf/tracex6_user.c
@@ -16,7 +16,7 @@
 #include <unistd.h>
 
 #include "bpf_load.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "perf-sys.h"
 
 #define SAMPLE_PERIOD  0x7fffffffffffffffULL
diff --git a/samples/bpf/tracex7_user.c b/samples/bpf/tracex7_user.c
index 8a52ac492e8b..ea6dae78f0df 100644
--- a/samples/bpf/tracex7_user.c
+++ b/samples/bpf/tracex7_user.c
@@ -3,7 +3,7 @@
 #include <stdio.h>
 #include <linux/bpf.h>
 #include <unistd.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 int main(int argc, char **argv)
diff --git a/samples/bpf/xdp_fwd_user.c b/samples/bpf/xdp_fwd_user.c
index 9c6606f57126..a87a2048ed32 100644
--- a/samples/bpf/xdp_fwd_user.c
+++ b/samples/bpf/xdp_fwd_user.c
@@ -26,7 +26,7 @@
 
 #include "bpf_load.h"
 #include "bpf_util.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 
 static int do_attach(int idx, int fd, const char *name)
diff --git a/samples/bpf/xdp_monitor_user.c b/samples/bpf/xdp_monitor_user.c
index 894bc64c2cac..ca187913ebe0 100644
--- a/samples/bpf/xdp_monitor_user.c
+++ b/samples/bpf/xdp_monitor_user.c
@@ -26,7 +26,7 @@ static const char *__doc_err_only__=
 #include <net/if.h>
 #include <time.h>
 
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 #include "bpf_util.h"
 
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index 23744a8aaf21..f6efaefd485b 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -28,7 +28,7 @@ static const char *__doc__ =
  * use bpf/libbpf.h), but cannot as (currently) needed for XDP
  * attaching to a device via bpf_set_link_xdp_fd()
  */
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_load.h"
 
 #include "bpf_util.h"
diff --git a/samples/bpf/xdp_redirect_map_user.c b/samples/bpf/xdp_redirect_map_user.c
index 7eae07d7293e..4445e76854b5 100644
--- a/samples/bpf/xdp_redirect_map_user.c
+++ b/samples/bpf/xdp_redirect_map_user.c
@@ -24,7 +24,7 @@
 
 #include "bpf_load.h"
 #include "bpf_util.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 static int ifindex_in;
 static int ifindex_out;
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
index b701b5c21342..81a69e36cb78 100644
--- a/samples/bpf/xdp_redirect_user.c
+++ b/samples/bpf/xdp_redirect_user.c
@@ -24,7 +24,7 @@
 
 #include "bpf_load.h"
 #include "bpf_util.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 static int ifindex_in;
 static int ifindex_out;
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index 6296741c1fbd..b2b4dfa776c8 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -16,7 +16,7 @@
 #include <sys/socket.h>
 #include <unistd.h>
 #include "bpf_load.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include <arpa/inet.h>
 #include <fcntl.h>
 #include <poll.h>
diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index f0a787268a87..a4ccc33adac0 100644
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -18,7 +18,7 @@
 #include <unistd.h>
 #include <time.h>
 #include "bpf_load.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 #include "bpf_util.h"
 #include "xdp_tx_iptunnel_common.h"
 
diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
index 4b8a7cf3e63b..7fe60f6f7d53 100644
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -38,7 +38,7 @@
 
 #include "bpf_load.h"
 #include "bpf_util.h"
-#include "libbpf.h"
+#include <bpf/bpf.h>
 
 #include "xdpsock.h"
 
-- 
2.17.0

[PATCH bpf-next 2/4] samples: bpf: rename libbpf.h to bpf_insn.h

[Jakub Kicinski]

The libbpf.h file in samples is clashing with libbpf's header.
Since it only includes a subset of filter.h instruction helpers
rename it to bpf_insn.h.  Drop the unnecessary include of bpf/bpf.h.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 samples/bpf/{libbpf.h => bpf_insn.h}    | 8 +++-----
 samples/bpf/cookie_uid_helper_example.c | 2 +-
 samples/bpf/fds_example.c               | 4 +++-
 samples/bpf/sock_example.c              | 3 ++-
 samples/bpf/test_cgrp2_attach.c         | 3 ++-
 samples/bpf/test_cgrp2_attach2.c        | 3 ++-
 samples/bpf/test_cgrp2_sock.c           | 3 ++-
 samples/bpf/test_cgrp2_sock2.c          | 3 ++-
 8 files changed, 17 insertions(+), 12 deletions(-)
 rename samples/bpf/{libbpf.h => bpf_insn.h} (98%)

diff --git a/samples/bpf/libbpf.h b/samples/bpf/bpf_insn.h
similarity index 98%
rename from samples/bpf/libbpf.h
rename to samples/bpf/bpf_insn.h
index 18bfee5aab6b..20dc5cefec84 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/bpf_insn.h
@@ -1,9 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-/* eBPF mini library */
-#ifndef __LIBBPF_H
-#define __LIBBPF_H
-
-#include <bpf/bpf.h>
+/* eBPF instruction mini library */
+#ifndef __BPF_INSN_H
+#define __BPF_INSN_H
 
 struct bpf_insn;
 
diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c
index 8eca27e595ae..deb0e3e0324d 100644
--- a/samples/bpf/cookie_uid_helper_example.c
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -51,7 +51,7 @@
 #include <sys/types.h>
 #include <unistd.h>
 #include <bpf/bpf.h>
-#include "libbpf.h"
+#include "bpf_insn.h"
 
 #define PORT 8888
 
diff --git a/samples/bpf/fds_example.c b/samples/bpf/fds_example.c
index e29bd52ff9e8..9854854f05d1 100644
--- a/samples/bpf/fds_example.c
+++ b/samples/bpf/fds_example.c
@@ -12,8 +12,10 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 
+#include <bpf/bpf.h>
+
+#include "bpf_insn.h"
 #include "bpf_load.h"
-#include "libbpf.h"
 #include "sock_example.h"
 
 #define BPF_F_PIN	(1 << 0)
diff --git a/samples/bpf/sock_example.c b/samples/bpf/sock_example.c
index 33a637507c00..60ec467c78ab 100644
--- a/samples/bpf/sock_example.c
+++ b/samples/bpf/sock_example.c
@@ -26,7 +26,8 @@
 #include <linux/if_ether.h>
 #include <linux/ip.h>
 #include <stddef.h>
-#include "libbpf.h"
+#include <bpf/bpf.h>
+#include "bpf_insn.h"
 #include "sock_example.h"
 
 char bpf_log_buf[BPF_LOG_BUF_SIZE];
diff --git a/samples/bpf/test_cgrp2_attach.c b/samples/bpf/test_cgrp2_attach.c
index 4bfcaf93fcf3..20fbd1241db3 100644
--- a/samples/bpf/test_cgrp2_attach.c
+++ b/samples/bpf/test_cgrp2_attach.c
@@ -28,8 +28,9 @@
 #include <fcntl.h>
 
 #include <linux/bpf.h>
+#include <bpf/bpf.h>
 
-#include "libbpf.h"
+#include "bpf_insn.h"
 
 enum {
 	MAP_KEY_PACKETS,
diff --git a/samples/bpf/test_cgrp2_attach2.c b/samples/bpf/test_cgrp2_attach2.c
index 1af412ec6007..b453e6a161be 100644
--- a/samples/bpf/test_cgrp2_attach2.c
+++ b/samples/bpf/test_cgrp2_attach2.c
@@ -24,8 +24,9 @@
 #include <unistd.h>
 
 #include <linux/bpf.h>
+#include <bpf/bpf.h>
 
-#include "libbpf.h"
+#include "bpf_insn.h"
 #include "cgroup_helpers.h"
 
 #define FOO		"/foo"
diff --git a/samples/bpf/test_cgrp2_sock.c b/samples/bpf/test_cgrp2_sock.c
index e79594dd629b..b0811da5a00f 100644
--- a/samples/bpf/test_cgrp2_sock.c
+++ b/samples/bpf/test_cgrp2_sock.c
@@ -21,8 +21,9 @@
 #include <net/if.h>
 #include <inttypes.h>
 #include <linux/bpf.h>
+#include <bpf/bpf.h>
 
-#include "libbpf.h"
+#include "bpf_insn.h"
 
 char bpf_log_buf[BPF_LOG_BUF_SIZE];
 
diff --git a/samples/bpf/test_cgrp2_sock2.c b/samples/bpf/test_cgrp2_sock2.c
index e53f1f6f0867..3b5be2364975 100644
--- a/samples/bpf/test_cgrp2_sock2.c
+++ b/samples/bpf/test_cgrp2_sock2.c
@@ -19,8 +19,9 @@
 #include <fcntl.h>
 #include <net/if.h>
 #include <linux/bpf.h>
+#include <bpf/bpf.h>
 
-#include "libbpf.h"
+#include "bpf_insn.h"
 #include "bpf_load.h"
 
 static int usage(const char *argv0)
-- 
2.17.0

[PATCH bpf-next 3/4] samples: bpf: fix build after move to compiling full libbpf.a

[Jakub Kicinski]

There are many ways users may compile samples, some of them got
broken by commit 5f9380572b4b ("samples: bpf: compile and link
against full libbpf").  Improve path resolution and make libbpf
building a dependency of source files to force its build.

Samples should now again build with any of:
 cd samples/bpf; make
 make samples/bpf
 make -C samples/bpf
 cd samples/bpf; make O=builddir
 make samples/bpf O=builddir
 make -C samples/bpf O=builddir

Fixes: 5f9380572b4b ("samples: bpf: compile and link against full libbpf")
Reported-by: Björn Töpel <bjorn.topel@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 samples/bpf/Makefile | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 9e255ca4059a..bed205ab1f81 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -1,4 +1,8 @@
 # SPDX-License-Identifier: GPL-2.0
+
+BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
+TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools
+
 # List of programs to build
 hostprogs-y := test_lru_dist
 hostprogs-y += sock_example
@@ -49,7 +53,8 @@ hostprogs-y += xdpsock
 hostprogs-y += xdp_fwd
 
 # Libbpf dependencies
-LIBBPF := ../../tools/lib/bpf/libbpf.a
+LIBBPF = $(TOOLS_PATH)/lib/bpf/libbpf.a
+
 CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
 TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
 
@@ -233,15 +238,15 @@ CLANG_ARCH_ARGS = -target $(ARCH)
 endif
 
 # Trick to allow make to be run from this directory
-all: $(LIBBPF)
-	$(MAKE) -C ../../ $(CURDIR)/
+all:
+	$(MAKE) -C ../../ $(CURDIR)/ BPF_SAMPLES_PATH=$(CURDIR)
 
 clean:
 	$(MAKE) -C ../../ M=$(CURDIR) clean
 	@rm -f *~
 
 $(LIBBPF): FORCE
-	$(MAKE) -C $(dir $@)
+	$(MAKE) -C $(dir $@) O= srctree=$(BPF_SAMPLES_PATH)/../../
 
 $(obj)/syscall_nrs.s:	$(src)/syscall_nrs.c
 	$(call if_changed_dep,cc_s_c)
@@ -272,7 +277,8 @@ verify_target_bpf: verify_cmds
 		exit 2; \
 	else true; fi
 
-$(src)/*.c: verify_target_bpf
+$(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
+$(src)/*.c: verify_target_bpf $(LIBBPF)
 
 $(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
 
-- 
2.17.0

[PATCH bpf-next 4/4] samples: bpf: move libbpf from object dependencies to libs

[Jakub Kicinski]

Make complains that it doesn't know how to make libbpf.a:

scripts/Makefile.host:106: target 'samples/bpf/../../tools/lib/bpf/libbpf.a' doesn't match the target pattern

Now that we have it as a dependency of the sources simply add libbpf.a
to libraries not objects.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 samples/bpf/Makefile | 145 +++++++++++++++----------------------------
 1 file changed, 51 insertions(+), 94 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index bed205ab1f81..64cdbb4d22a6 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -58,55 +58,53 @@ LIBBPF = $(TOOLS_PATH)/lib/bpf/libbpf.a
 CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
 TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
 
-test_lru_dist-objs := test_lru_dist.o $(LIBBPF)
-sock_example-objs := sock_example.o $(LIBBPF)
-fds_example-objs := bpf_load.o $(LIBBPF) fds_example.o
-sockex1-objs := bpf_load.o $(LIBBPF) sockex1_user.o
-sockex2-objs := bpf_load.o $(LIBBPF) sockex2_user.o
-sockex3-objs := bpf_load.o $(LIBBPF) sockex3_user.o
-tracex1-objs := bpf_load.o $(LIBBPF) tracex1_user.o
-tracex2-objs := bpf_load.o $(LIBBPF) tracex2_user.o
-tracex3-objs := bpf_load.o $(LIBBPF) tracex3_user.o
-tracex4-objs := bpf_load.o $(LIBBPF) tracex4_user.o
-tracex5-objs := bpf_load.o $(LIBBPF) tracex5_user.o
-tracex6-objs := bpf_load.o $(LIBBPF) tracex6_user.o
-tracex7-objs := bpf_load.o $(LIBBPF) tracex7_user.o
-load_sock_ops-objs := bpf_load.o $(LIBBPF) load_sock_ops.o
-test_probe_write_user-objs := bpf_load.o $(LIBBPF) test_probe_write_user_user.o
-trace_output-objs := bpf_load.o $(LIBBPF) trace_output_user.o $(TRACE_HELPERS)
-lathist-objs := bpf_load.o $(LIBBPF) lathist_user.o
-offwaketime-objs := bpf_load.o $(LIBBPF) offwaketime_user.o $(TRACE_HELPERS)
-spintest-objs := bpf_load.o $(LIBBPF) spintest_user.o $(TRACE_HELPERS)
-map_perf_test-objs := bpf_load.o $(LIBBPF) map_perf_test_user.o
-test_overhead-objs := bpf_load.o $(LIBBPF) test_overhead_user.o
-test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o $(LIBBPF)
-test_cgrp2_attach-objs := test_cgrp2_attach.o $(LIBBPF)
-test_cgrp2_attach2-objs := test_cgrp2_attach2.o $(LIBBPF) $(CGROUP_HELPERS)
-test_cgrp2_sock-objs := test_cgrp2_sock.o $(LIBBPF)
-test_cgrp2_sock2-objs := bpf_load.o $(LIBBPF) test_cgrp2_sock2.o
-xdp1-objs := xdp1_user.o $(LIBBPF)
+fds_example-objs := bpf_load.o fds_example.o
+sockex1-objs := bpf_load.o sockex1_user.o
+sockex2-objs := bpf_load.o sockex2_user.o
+sockex3-objs := bpf_load.o sockex3_user.o
+tracex1-objs := bpf_load.o tracex1_user.o
+tracex2-objs := bpf_load.o tracex2_user.o
+tracex3-objs := bpf_load.o tracex3_user.o
+tracex4-objs := bpf_load.o tracex4_user.o
+tracex5-objs := bpf_load.o tracex5_user.o
+tracex6-objs := bpf_load.o tracex6_user.o
+tracex7-objs := bpf_load.o tracex7_user.o
+load_sock_ops-objs := bpf_load.o load_sock_ops.o
+test_probe_write_user-objs := bpf_load.o test_probe_write_user_user.o
+trace_output-objs := bpf_load.o trace_output_user.o $(TRACE_HELPERS)
+lathist-objs := bpf_load.o lathist_user.o
+offwaketime-objs := bpf_load.o offwaketime_user.o $(TRACE_HELPERS)
+spintest-objs := bpf_load.o spintest_user.o $(TRACE_HELPERS)
+map_perf_test-objs := bpf_load.o map_perf_test_user.o
+test_overhead-objs := bpf_load.o test_overhead_user.o
+test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
+test_cgrp2_attach-objs := test_cgrp2_attach.o
+test_cgrp2_attach2-objs := test_cgrp2_attach2.o $(CGROUP_HELPERS)
+test_cgrp2_sock-objs := test_cgrp2_sock.o
+test_cgrp2_sock2-objs := bpf_load.o test_cgrp2_sock2.o
+xdp1-objs := xdp1_user.o
 # reuse xdp1 source intentionally
-xdp2-objs := xdp1_user.o $(LIBBPF)
-xdp_router_ipv4-objs := bpf_load.o $(LIBBPF) xdp_router_ipv4_user.o
-test_current_task_under_cgroup-objs := bpf_load.o $(LIBBPF) $(CGROUP_HELPERS) \
+xdp2-objs := xdp1_user.o
+xdp_router_ipv4-objs := bpf_load.o xdp_router_ipv4_user.o
+test_current_task_under_cgroup-objs := bpf_load.o $(CGROUP_HELPERS) \
 				       test_current_task_under_cgroup_user.o
-trace_event-objs := bpf_load.o $(LIBBPF) trace_event_user.o $(TRACE_HELPERS)
-sampleip-objs := bpf_load.o $(LIBBPF) sampleip_user.o $(TRACE_HELPERS)
-tc_l2_redirect-objs := bpf_load.o $(LIBBPF) tc_l2_redirect_user.o
-lwt_len_hist-objs := bpf_load.o $(LIBBPF) lwt_len_hist_user.o
-xdp_tx_iptunnel-objs := bpf_load.o $(LIBBPF) xdp_tx_iptunnel_user.o
-test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o
-per_socket_stats_example-objs := cookie_uid_helper_example.o $(LIBBPF)
-xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o
-xdp_redirect_map-objs := bpf_load.o $(LIBBPF) xdp_redirect_map_user.o
-xdp_redirect_cpu-objs := bpf_load.o $(LIBBPF) xdp_redirect_cpu_user.o
-xdp_monitor-objs := bpf_load.o $(LIBBPF) xdp_monitor_user.o
-xdp_rxq_info-objs := xdp_rxq_info_user.o $(LIBBPF)
-syscall_tp-objs := bpf_load.o $(LIBBPF) syscall_tp_user.o
-cpustat-objs := bpf_load.o $(LIBBPF) cpustat_user.o
-xdp_adjust_tail-objs := xdp_adjust_tail_user.o $(LIBBPF)
-xdpsock-objs := bpf_load.o $(LIBBPF) xdpsock_user.o
-xdp_fwd-objs := bpf_load.o $(LIBBPF) xdp_fwd_user.o
+trace_event-objs := bpf_load.o trace_event_user.o $(TRACE_HELPERS)
+sampleip-objs := bpf_load.o sampleip_user.o $(TRACE_HELPERS)
+tc_l2_redirect-objs := bpf_load.o tc_l2_redirect_user.o
+lwt_len_hist-objs := bpf_load.o lwt_len_hist_user.o
+xdp_tx_iptunnel-objs := bpf_load.o xdp_tx_iptunnel_user.o
+test_map_in_map-objs := bpf_load.o test_map_in_map_user.o
+per_socket_stats_example-objs := cookie_uid_helper_example.o
+xdp_redirect-objs := bpf_load.o xdp_redirect_user.o
+xdp_redirect_map-objs := bpf_load.o xdp_redirect_map_user.o
+xdp_redirect_cpu-objs := bpf_load.o xdp_redirect_cpu_user.o
+xdp_monitor-objs := bpf_load.o xdp_monitor_user.o
+xdp_rxq_info-objs := xdp_rxq_info_user.o
+syscall_tp-objs := bpf_load.o syscall_tp_user.o
+cpustat-objs := bpf_load.o cpustat_user.o
+xdp_adjust_tail-objs := xdp_adjust_tail_user.o
+xdpsock-objs := bpf_load.o xdpsock_user.o
+xdp_fwd-objs := bpf_load.o xdp_fwd_user.o
 
 # Tell kbuild to always build the programs
 always := $(hostprogs-y)
@@ -178,53 +176,12 @@ HOSTCFLAGS_spintest_user.o += -I$(srctree)/tools/lib/bpf/
 HOSTCFLAGS_trace_event_user.o += -I$(srctree)/tools/lib/bpf/
 HOSTCFLAGS_sampleip_user.o += -I$(srctree)/tools/lib/bpf/
 
-HOSTLOADLIBES_test_lru_dist += -lelf
-HOSTLOADLIBES_sock_example += -lelf
-HOSTLOADLIBES_fds_example += -lelf
-HOSTLOADLIBES_sockex1 += -lelf
-HOSTLOADLIBES_sockex2 += -lelf
-HOSTLOADLIBES_sockex3 += -lelf
-HOSTLOADLIBES_tracex1 += -lelf
-HOSTLOADLIBES_tracex2 += -lelf
-HOSTLOADLIBES_tracex3 += -lelf
-HOSTLOADLIBES_tracex4 += -lelf -lrt
-HOSTLOADLIBES_tracex5 += -lelf
-HOSTLOADLIBES_tracex6 += -lelf
-HOSTLOADLIBES_tracex7 += -lelf
-HOSTLOADLIBES_test_cgrp2_array_pin += -lelf
-HOSTLOADLIBES_test_cgrp2_attach += -lelf
-HOSTLOADLIBES_test_cgrp2_attach2 += -lelf
-HOSTLOADLIBES_test_cgrp2_sock += -lelf
-HOSTLOADLIBES_test_cgrp2_sock2 += -lelf
-HOSTLOADLIBES_load_sock_ops += -lelf
-HOSTLOADLIBES_test_probe_write_user += -lelf
-HOSTLOADLIBES_trace_output += -lelf -lrt
-HOSTLOADLIBES_lathist += -lelf
-HOSTLOADLIBES_offwaketime += -lelf
-HOSTLOADLIBES_spintest += -lelf
-HOSTLOADLIBES_map_perf_test += -lelf -lrt
-HOSTLOADLIBES_test_overhead += -lelf -lrt
-HOSTLOADLIBES_xdp1 += -lelf
-HOSTLOADLIBES_xdp2 += -lelf
-HOSTLOADLIBES_xdp_router_ipv4 += -lelf
-HOSTLOADLIBES_test_current_task_under_cgroup += -lelf
-HOSTLOADLIBES_trace_event += -lelf
-HOSTLOADLIBES_sampleip += -lelf
-HOSTLOADLIBES_tc_l2_redirect += -l elf
-HOSTLOADLIBES_lwt_len_hist += -l elf
-HOSTLOADLIBES_xdp_tx_iptunnel += -lelf
-HOSTLOADLIBES_test_map_in_map += -lelf
-HOSTLOADLIBES_per_socket_stats_example += -lelf
-HOSTLOADLIBES_xdp_redirect += -lelf
-HOSTLOADLIBES_xdp_redirect_map += -lelf
-HOSTLOADLIBES_xdp_redirect_cpu += -lelf
-HOSTLOADLIBES_xdp_monitor += -lelf
-HOSTLOADLIBES_xdp_rxq_info += -lelf
-HOSTLOADLIBES_syscall_tp += -lelf
-HOSTLOADLIBES_cpustat += -lelf
-HOSTLOADLIBES_xdp_adjust_tail += -lelf
-HOSTLOADLIBES_xdpsock += -lelf -pthread
-HOSTLOADLIBES_xdp_fwd += -lelf
+HOST_LOADLIBES		+= $(LIBBPF) -lelf
+HOSTLOADLIBES_tracex4		+= -lrt
+HOSTLOADLIBES_trace_output	+= -lrt
+HOSTLOADLIBES_map_perf_test	+= -lrt
+HOSTLOADLIBES_test_overhead	+= -lrt
+HOSTLOADLIBES_xdpsock		+= -pthread
 
 # Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
 #  make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
-- 
2.17.0

Re: [PATCH bpf-next 0/4] samples: bpf: fix build after move to full libbpf

[Jesper Dangaard Brouer]

On Fri, 11 May 2018 17:17:25 -0700
Jakub Kicinski <jakub.kicinski@netronome.com> wrote:

> Following patches address build issues after recent move to libbpf.
> For out-of-tree builds we would see the following error:
> 
> gcc: error: samples/bpf/../../tools/lib/bpf/libbpf.a: No such file or directory
> 
> Mini-library called libbpf.h in samples is renamed to bpf_insn.h,
> using linux/filter.h seems not completely trivial since some samples
> get upset when order on include search path in changed.  We do have
> to rename libbpf.h, however, because otherwise it's hard to reliably
> get to libbpf's header in out-of-tree builds.


Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>

Thank you for doing this... this mini-library also called libbpf.h have
confused me before, and I bet it will/would confuse others as well.
Glad to see it being renamed :-)

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

Re: [PATCH bpf-next 3/4] samples: bpf: fix build after move to compiling full libbpf.a

[Jakub Kicinski]

On Fri, 11 May 2018 17:17:28 -0700, Jakub Kicinski wrote:
> There are many ways users may compile samples, some of them got
> broken by commit 5f9380572b4b ("samples: bpf: compile and link
> against full libbpf").  Improve path resolution and make libbpf
> building a dependency of source files to force its build.
> 
> Samples should now again build with any of:
>  cd samples/bpf; make
>  make samples/bpf
>  make -C samples/bpf
>  cd samples/bpf; make O=builddir
>  make samples/bpf O=builddir
>  make -C samples/bpf O=builddir
> 
> Fixes: 5f9380572b4b ("samples: bpf: compile and link against full libbpf")
> Reported-by: Björn Töpel <bjorn.topel@gmail.com>
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Unfortunately Björn reports this still doesn't fix the build for him.
Investigating further.

Re: [PATCH bpf-next 3/4] samples: bpf: fix build after move to compiling full libbpf.a

[Daniel Borkmann]

On 05/12/2018 09:38 PM, Jakub Kicinski wrote:
> On Fri, 11 May 2018 17:17:28 -0700, Jakub Kicinski wrote:
>> There are many ways users may compile samples, some of them got
>> broken by commit 5f9380572b4b ("samples: bpf: compile and link
>> against full libbpf").  Improve path resolution and make libbpf
>> building a dependency of source files to force its build.
>>
>> Samples should now again build with any of:
>>  cd samples/bpf; make
>>  make samples/bpf
>>  make -C samples/bpf
>>  cd samples/bpf; make O=builddir
>>  make samples/bpf O=builddir
>>  make -C samples/bpf O=builddir
>>
>> Fixes: 5f9380572b4b ("samples: bpf: compile and link against full libbpf")
>> Reported-by: Björn Töpel <bjorn.topel@gmail.com>
>> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> 
> Unfortunately Björn reports this still doesn't fix the build for him.
> Investigating further.

Ok, thanks for letting us know.

Re: [PATCH bpf-next 3/4] samples: bpf: fix build after move to compiling full libbpf.a

[Y Song]

On Fri, May 11, 2018 at 5:17 PM, Jakub Kicinski
<jakub.kicinski@netronome.com> wrote:
> There are many ways users may compile samples, some of them got
> broken by commit 5f9380572b4b ("samples: bpf: compile and link
> against full libbpf").  Improve path resolution and make libbpf
> building a dependency of source files to force its build.
>
> Samples should now again build with any of:
>  cd samples/bpf; make
>  make samples/bpf
>  make -C samples/bpf
>  cd samples/bpf; make O=builddir
>  make samples/bpf O=builddir
>  make -C samples/bpf O=builddir

I typically built samples/bpf/ this way:
    export KBUILD_OUTPUT=/home/yhs/linux-bld
at linux source directory:
    make defconfig
in /home/yhs/linux-bld,
    make -j100 && make headers_install && make samples/bpf/

With this patch, the build for samples/bpf/ still failed.

-bash-4.2$ make samples/bpf/
  CHK     include/config/kernel.release
  Using /data/users/yhs/work/net-next as source for kernel
  GEN     ./Makefile
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CHK     include/generated/bounds.h
  CHK     include/generated/timeconst.h
  CHK     include/generated/asm-offsets.h
  CALL    /data/users/yhs/work/net-next/scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     scripts/mod/devicetable-offsets.h
scripts/Makefile.host:106: target
`samples/bpf//data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/libbpf.a'
doesn't match the target pattern
make -C /data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/
O= srctree=/data/users/yhs/work/net-next/samples/bpf/../../

Auto-detecting system features:
...                        libelf: [ OFF ]
...                           bpf: [ OFF ]

No libelf found
make[4]: *** [elfdep] Error 1
make[3]: *** [/data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/libbpf.a]
Error 2
make[2]: *** [samples/bpf/] Error 2
make[1]: *** [sub-make] Error 2
make: *** [__sub-make] Error 2
-bash-4.2$

I noticied that I might use BPF_SAMPLES_PATH variable to tell where is
the samples/bpf source.
Below is what I did:
-bash-4.2$ BPF_SAMPLES_PATH=../../../net-next/samples/bpf make
samples/bpf/
  CHK     include/config/kernel.release
  Using /data/users/yhs/work/net-next as source for kernel
  GEN     ./Makefile
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CHK     include/generated/bounds.h
  CHK     include/generated/timeconst.h
  CHK     include/generated/asm-offsets.h
  CALL    /data/users/yhs/work/net-next/scripts/checksyscalls.sh
  DESCEND  objtool
  CHK     scripts/mod/devicetable-offsets.h
scripts/Makefile.host:106: target
`samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a'
doesn't match the target pattern
  CHK     samples/bpf/syscall_nrs.h
  HOSTCC  samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a
gcc: fatal error: no input files
compilation terminated.
make[3]: *** [samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a]
Error 4
make[2]: *** [samples/bpf/] Error 2
make[1]: *** [sub-make] Error 2
make: *** [__sub-make] Error 2
-bash-4.2$

-bash-4.2$ pwd
/home/yhs/work
-bash-4.2$ ls
linux-bld  net-next
-bash-4.2$

>
> Fixes: 5f9380572b4b ("samples: bpf: compile and link against full libbpf")
> Reported-by: Björn Töpel <bjorn.topel@gmail.com>
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> ---
>  samples/bpf/Makefile | 16 +++++++++++-----
>  1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
> index 9e255ca4059a..bed205ab1f81 100644
> --- a/samples/bpf/Makefile
> +++ b/samples/bpf/Makefile
> @@ -1,4 +1,8 @@
>  # SPDX-License-Identifier: GPL-2.0
> +
> +BPF_SAMPLES_PATH ?= $(abspath $(srctree)/$(src))
> +TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools
> +
>  # List of programs to build
>  hostprogs-y := test_lru_dist
>  hostprogs-y += sock_example
> @@ -49,7 +53,8 @@ hostprogs-y += xdpsock
>  hostprogs-y += xdp_fwd
>
>  # Libbpf dependencies
> -LIBBPF := ../../tools/lib/bpf/libbpf.a
> +LIBBPF = $(TOOLS_PATH)/lib/bpf/libbpf.a
> +
>  CGROUP_HELPERS := ../../tools/testing/selftests/bpf/cgroup_helpers.o
>  TRACE_HELPERS := ../../tools/testing/selftests/bpf/trace_helpers.o
>
> @@ -233,15 +238,15 @@ CLANG_ARCH_ARGS = -target $(ARCH)
>  endif
>
>  # Trick to allow make to be run from this directory
> -all: $(LIBBPF)
> -       $(MAKE) -C ../../ $(CURDIR)/
> +all:
> +       $(MAKE) -C ../../ $(CURDIR)/ BPF_SAMPLES_PATH=$(CURDIR)
>
>  clean:
>         $(MAKE) -C ../../ M=$(CURDIR) clean
>         @rm -f *~
>
>  $(LIBBPF): FORCE
> -       $(MAKE) -C $(dir $@)
> +       $(MAKE) -C $(dir $@) O= srctree=$(BPF_SAMPLES_PATH)/../../
>
>  $(obj)/syscall_nrs.s:  $(src)/syscall_nrs.c
>         $(call if_changed_dep,cc_s_c)
> @@ -272,7 +277,8 @@ verify_target_bpf: verify_cmds
>                 exit 2; \
>         else true; fi
>
> -$(src)/*.c: verify_target_bpf
> +$(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
> +$(src)/*.c: verify_target_bpf $(LIBBPF)
>
>  $(obj)/tracex5_kern.o: $(obj)/syscall_nrs.h
>
> --
> 2.17.0
>

Re: [PATCH bpf-next 3/4] samples: bpf: fix build after move to compiling full libbpf.a

[Jakub Kicinski]

On Mon, 14 May 2018 12:12:05 -0700, Y Song wrote:
> On Fri, May 11, 2018 at 5:17 PM, Jakub Kicinski
> <jakub.kicinski@netronome.com> wrote:
> > There are many ways users may compile samples, some of them got
> > broken by commit 5f9380572b4b ("samples: bpf: compile and link
> > against full libbpf").  Improve path resolution and make libbpf
> > building a dependency of source files to force its build.
> >
> > Samples should now again build with any of:
> >  cd samples/bpf; make
> >  make samples/bpf
> >  make -C samples/bpf
> >  cd samples/bpf; make O=builddir
> >  make samples/bpf O=builddir
> >  make -C samples/bpf O=builddir  
> 
> I typically built samples/bpf/ this way:
>     export KBUILD_OUTPUT=/home/yhs/linux-bld
> at linux source directory:
>     make defconfig
> in /home/yhs/linux-bld,
>     make -j100 && make headers_install && make samples/bpf/

Thanks Yonghong!  I will add this to my tests.

> With this patch, the build for samples/bpf/ still failed.
> 
> -bash-4.2$ make samples/bpf/
>   CHK     include/config/kernel.release
>   Using /data/users/yhs/work/net-next as source for kernel
>   GEN     ./Makefile
>   CHK     include/generated/uapi/linux/version.h
>   CHK     include/generated/utsrelease.h
>   CHK     include/generated/bounds.h
>   CHK     include/generated/timeconst.h
>   CHK     include/generated/asm-offsets.h
>   CALL    /data/users/yhs/work/net-next/scripts/checksyscalls.sh
>   DESCEND  objtool
>   CHK     scripts/mod/devicetable-offsets.h
> scripts/Makefile.host:106: target
> `samples/bpf//data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/libbpf.a'
> doesn't match the target pattern
> make -C /data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/
> O= srctree=/data/users/yhs/work/net-next/samples/bpf/../../
> 
> Auto-detecting system features:
> ...                        libelf: [ OFF ]
> ...                           bpf: [ OFF ]
> 
> No libelf found

The problem now is that feature detection gets confused about where
its output directory is, I think.  This is very similar to what Björn
reported.

> make[4]: *** [elfdep] Error 1
> make[3]: *** [/data/users/yhs/work/net-next/samples/bpf/../../tools/lib/bpf/libbpf.a]
> Error 2
> make[2]: *** [samples/bpf/] Error 2
> make[1]: *** [sub-make] Error 2
> make: *** [__sub-make] Error 2
> -bash-4.2$
> 
> I noticied that I might use BPF_SAMPLES_PATH variable to tell where is
> the samples/bpf source.
> Below is what I did:
> -bash-4.2$ BPF_SAMPLES_PATH=../../../net-next/samples/bpf make
> samples/bpf/
>   CHK     include/config/kernel.release
>   Using /data/users/yhs/work/net-next as source for kernel
>   GEN     ./Makefile
>   CHK     include/generated/uapi/linux/version.h
>   CHK     include/generated/utsrelease.h
>   CHK     include/generated/bounds.h
>   CHK     include/generated/timeconst.h
>   CHK     include/generated/asm-offsets.h
>   CALL    /data/users/yhs/work/net-next/scripts/checksyscalls.sh
>   DESCEND  objtool
>   CHK     scripts/mod/devicetable-offsets.h
> scripts/Makefile.host:106: target
> `samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a'
> doesn't match the target pattern
>   CHK     samples/bpf/syscall_nrs.h
>   HOSTCC  samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a
> gcc: fatal error: no input files
> compilation terminated.
> make[3]: *** [samples/bpf/../../../net-next/samples/bpf/../../tools/lib/bpf/libbpf.a]
> Error 4
> make[2]: *** [samples/bpf/] Error 2
> make[1]: *** [sub-make] Error 2
> make: *** [__sub-make] Error 2
> -bash-4.2$
> 
> -bash-4.2$ pwd
> /home/yhs/work
> -bash-4.2$ ls
> linux-bld  net-next
> -bash-4.2$