Merge branch 'samples-bpf-remove-unmaintained-xdp-sample-utilities'

Toke Høiland-Jørgensen says:

====================
samples/bpf: Remove unmaintained XDP sample utilities

The samples/bpf directory in the kernel tree started out as a way of showcasing
different aspects of BPF functionality by writing small utility programs for
each feature. However, as the BPF subsystem has matured, the preferred way of
including userspace code with a feature has become the BPF selftests, which also
have the benefit of being consistently run as part of the BPF CI system.

As a result of this shift, the utilities in samples/bpf have seen little love,
and have slowly bitrotted. There have been sporadic cleanup patches over the
years, but it's clear that the utilities are far from maintained.

For XDP in particular, some of the utilities have been used as benchmarking aids
when implementing new kernel features, which seems to be the main reason they
have stuck around; any updates the utilities have seen have been targeted at
this use case. However, as the BPF subsystem as a whole has moved on, it has
become increasingly difficult to incorporate new features into these utilities
because they predate most of the modern BPF features (such as kfuncs and BTF).

Rather than try to update these utilities and keep maintaining them in the
kernel tree, we have ported the useful features of the utilities to the
xdp-tools package. In the porting process we also updated the utilities to take
advantage of modern BPF features, integrated them with libxdp, and polished the
user interface.

As these utilities are standalone tools, maintaining them out of tree is
simpler, and we plan to keep maintaining them in the xdp-tools repo. To direct
users of these utilities to the right place, this series removes the utilities
from samples/bpf, leaving in place only a couple of utilities whose
functionality have not yet been ported to xdp-tools.

The xdp-tools repository is located on Github at the following URL:

https://github.com/xdp-project/xdp-tools

The commits in the series removes one utility each, explaining how the
equivalent functionality can be obtained with xdp-tools.

v2:
- Add equivalent xdp-tools commands for each removed utility
v3:
- Add link to xdp-tools in the README

Toke Høiland-Jørgensen (7):
  samples/bpf: Remove the xdp_monitor utility
  samples/bpf: Remove the xdp_redirect* utilities
  samples/bpf: Remove the xdp_rxq_info utility
  samples/bpf: Remove the xdp1 and xdp2 utilities
  samples/bpf: Remove the xdp_sample_pkts utility
  samples/bpf: Cleanup .gitignore
  samples/bpf: Add note to README about the XDP utilities moved to
    xdp-tools

 samples/bpf/.gitignore                    |  12 -
 samples/bpf/Makefile                      |  48 +-
 samples/bpf/README.rst                    |   6 +
 samples/bpf/xdp1_kern.c                   | 100 ----
 samples/bpf/xdp1_user.c                   | 166 ------
 samples/bpf/xdp2_kern.c                   | 125 -----
 samples/bpf/xdp_monitor.bpf.c             |   8 -
 samples/bpf/xdp_monitor_user.c            | 118 -----
 samples/bpf/xdp_redirect.bpf.c            |  49 --
 samples/bpf/xdp_redirect_cpu.bpf.c        | 539 -------------------
 samples/bpf/xdp_redirect_cpu_user.c       | 559 --------------------
 samples/bpf/xdp_redirect_map.bpf.c        |  97 ----
 samples/bpf/xdp_redirect_map_multi.bpf.c  |  77 ---
 samples/bpf/xdp_redirect_map_multi_user.c | 232 --------
 samples/bpf/xdp_redirect_map_user.c       | 228 --------
 samples/bpf/xdp_redirect_user.c           | 172 ------
 samples/bpf/xdp_rxq_info_kern.c           | 140 -----
 samples/bpf/xdp_rxq_info_user.c           | 614 ----------------------
 samples/bpf/xdp_sample_pkts_kern.c        |  57 --
 samples/bpf/xdp_sample_pkts_user.c        | 196 -------
 20 files changed, 7 insertions(+), 3536 deletions(-)
 delete mode 100644 samples/bpf/xdp1_kern.c
 delete mode 100644 samples/bpf/xdp1_user.c
 delete mode 100644 samples/bpf/xdp2_kern.c
 delete mode 100644 samples/bpf/xdp_monitor.bpf.c
 delete mode 100644 samples/bpf/xdp_monitor_user.c
 delete mode 100644 samples/bpf/xdp_redirect.bpf.c
 delete mode 100644 samples/bpf/xdp_redirect_cpu.bpf.c
 delete mode 100644 samples/bpf/xdp_redirect_cpu_user.c
 delete mode 100644 samples/bpf/xdp_redirect_map.bpf.c
 delete mode 100644 samples/bpf/xdp_redirect_map_multi.bpf.c
 delete mode 100644 samples/bpf/xdp_redirect_map_multi_user.c
 delete mode 100644 samples/bpf/xdp_redirect_map_user.c
 delete mode 100644 samples/bpf/xdp_redirect_user.c
 delete mode 100644 samples/bpf/xdp_rxq_info_kern.c
 delete mode 100644 samples/bpf/xdp_rxq_info_user.c
 delete mode 100644 samples/bpf/xdp_sample_pkts_kern.c
 delete mode 100644 samples/bpf/xdp_sample_pkts_user.c
====================

Link: https://lore.kernel.org/r/20230824102255.1561885-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

Author: Alexei Starovoitov

samples/bpf/.gitignore

@@ -37,22 +37,10 @@ tracex4
 tracex5
 tracex6
 tracex7
-xdp1
-xdp2
 xdp_adjust_tail
 xdp_fwd
-xdp_monitor
-xdp_redirect
-xdp_redirect_cpu
-xdp_redirect_map
-xdp_redirect_map_multi
 xdp_router_ipv4
-xdp_rxq_info
-xdp_sample_pkts
 xdp_tx_iptunnel
-xdpsock
-xdpsock_ctrl_proc
-xsk_fwd
 testfile.img
 hbm_out.log
 iperf.*

samples/bpf/Makefile

@@ -30,8 +30,6 @@ tprogs-y += test_cgrp2_array_pin
 tprogs-y += test_cgrp2_attach
 tprogs-y += test_cgrp2_sock
 tprogs-y += test_cgrp2_sock2
-tprogs-y += xdp1
-tprogs-y += xdp2
 tprogs-y += xdp_router_ipv4
 tprogs-y += test_current_task_under_cgroup
 tprogs-y += trace_event
@@ -41,22 +39,14 @@ tprogs-y += lwt_len_hist
 tprogs-y += xdp_tx_iptunnel
 tprogs-y += test_map_in_map
 tprogs-y += per_socket_stats_example
-tprogs-y += xdp_rxq_info
 tprogs-y += syscall_tp
 tprogs-y += cpustat
 tprogs-y += xdp_adjust_tail
 tprogs-y += xdp_fwd
 tprogs-y += task_fd_query
-tprogs-y += xdp_sample_pkts
 tprogs-y += ibumad
 tprogs-y += hbm
 
-tprogs-y += xdp_redirect_cpu
-tprogs-y += xdp_redirect_map_multi
-tprogs-y += xdp_redirect_map
-tprogs-y += xdp_redirect
-tprogs-y += xdp_monitor
-
 # Libbpf dependencies
 LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf
 LIBBPF_OUTPUT = $(abspath $(BPF_SAMPLES_PATH))/libbpf
@@ -90,9 +80,6 @@ test_cgrp2_array_pin-objs := test_cgrp2_array_pin.o
 test_cgrp2_attach-objs := test_cgrp2_attach.o
 test_cgrp2_sock-objs := test_cgrp2_sock.o
 test_cgrp2_sock2-objs := test_cgrp2_sock2.o
-xdp1-objs := xdp1_user.o
-# reuse xdp1 source intentionally
-xdp2-objs := xdp1_user.o
 test_current_task_under_cgroup-objs := $(CGROUP_HELPERS) \
 				       test_current_task_under_cgroup_user.o
 trace_event-objs := trace_event_user.o $(TRACE_HELPERS)
@@ -102,21 +89,14 @@ lwt_len_hist-objs := lwt_len_hist_user.o
 xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o
 test_map_in_map-objs := test_map_in_map_user.o
 per_socket_stats_example-objs := cookie_uid_helper_example.o
-xdp_rxq_info-objs := xdp_rxq_info_user.o
 syscall_tp-objs := syscall_tp_user.o
 cpustat-objs := cpustat_user.o
 xdp_adjust_tail-objs := xdp_adjust_tail_user.o
 xdp_fwd-objs := xdp_fwd_user.o
 task_fd_query-objs := task_fd_query_user.o $(TRACE_HELPERS)
-xdp_sample_pkts-objs := xdp_sample_pkts_user.o
 ibumad-objs := ibumad_user.o
 hbm-objs := hbm.o $(CGROUP_HELPERS)
 
-xdp_redirect_map_multi-objs := xdp_redirect_map_multi_user.o $(XDP_SAMPLE)
-xdp_redirect_cpu-objs := xdp_redirect_cpu_user.o $(XDP_SAMPLE)
-xdp_redirect_map-objs := xdp_redirect_map_user.o $(XDP_SAMPLE)
-xdp_redirect-objs := xdp_redirect_user.o $(XDP_SAMPLE)
-xdp_monitor-objs := xdp_monitor_user.o $(XDP_SAMPLE)
 xdp_router_ipv4-objs := xdp_router_ipv4_user.o $(XDP_SAMPLE)
 
 # Tell kbuild to always build the programs
@@ -145,8 +125,6 @@ always-y += test_overhead_raw_tp.bpf.o
 always-y += test_overhead_kprobe.bpf.o
 always-y += parse_varlen.o parse_simple.o parse_ldabs.o
 always-y += test_cgrp2_tc.bpf.o
-always-y += xdp1_kern.o
-always-y += xdp2_kern.o
 always-y += test_current_task_under_cgroup.bpf.o
 always-y += trace_event_kern.o
 always-y += sampleip_kern.o
@@ -162,14 +140,12 @@ always-y += tcp_clamp_kern.o
 always-y += tcp_basertt_kern.o
 always-y += tcp_tos_reflect_kern.o
 always-y += tcp_dumpstats_kern.o
-always-y += xdp_rxq_info_kern.o
 always-y += xdp2skb_meta_kern.o
 always-y += syscall_tp_kern.o
 always-y += cpustat_kern.o
 always-y += xdp_adjust_tail_kern.o
 always-y += xdp_fwd_kern.o
 always-y += task_fd_query_kern.o
-always-y += xdp_sample_pkts_kern.o
 always-y += ibumad_kern.o
 always-y += hbm_out_kern.o
 always-y += hbm_edt_kern.o
@@ -207,11 +183,6 @@ TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
 endif
 
 TPROGS_LDLIBS			+= $(LIBBPF) -lelf -lz
-TPROGLDLIBS_xdp_monitor		+= -lm
-TPROGLDLIBS_xdp_redirect	+= -lm
-TPROGLDLIBS_xdp_redirect_cpu	+= -lm
-TPROGLDLIBS_xdp_redirect_map	+= -lm
-TPROGLDLIBS_xdp_redirect_map_multi += -lm
 TPROGLDLIBS_xdp_router_ipv4	+= -lm -pthread
 TPROGLDLIBS_tracex4		+= -lrt
 TPROGLDLIBS_trace_output	+= -lrt
@@ -326,11 +297,6 @@ $(obj)/$(TRACE_HELPERS) $(obj)/$(CGROUP_HELPERS) $(obj)/$(XDP_SAMPLE): | libbpf_
 
 .PHONY: libbpf_hdrs
 
-$(obj)/xdp_redirect_cpu_user.o: $(obj)/xdp_redirect_cpu.skel.h
-$(obj)/xdp_redirect_map_multi_user.o: $(obj)/xdp_redirect_map_multi.skel.h
-$(obj)/xdp_redirect_map_user.o: $(obj)/xdp_redirect_map.skel.h
-$(obj)/xdp_redirect_user.o: $(obj)/xdp_redirect.skel.h
-$(obj)/xdp_monitor_user.o: $(obj)/xdp_monitor.skel.h
 $(obj)/xdp_router_ipv4_user.o: $(obj)/xdp_router_ipv4.skel.h
 
 $(obj)/tracex5.bpf.o: $(obj)/syscall_nrs.h
@@ -383,11 +349,6 @@ endef
 
 CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
 
-$(obj)/xdp_redirect_cpu.bpf.o: $(obj)/xdp_sample.bpf.o
-$(obj)/xdp_redirect_map_multi.bpf.o: $(obj)/xdp_sample.bpf.o
-$(obj)/xdp_redirect_map.bpf.o: $(obj)/xdp_sample.bpf.o
-$(obj)/xdp_redirect.bpf.o: $(obj)/xdp_sample.bpf.o
-$(obj)/xdp_monitor.bpf.o: $(obj)/xdp_sample.bpf.o
 $(obj)/xdp_router_ipv4.bpf.o: $(obj)/xdp_sample.bpf.o
 
 $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
@@ -398,16 +359,9 @@ $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/x
 		-I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \
 		-c $(filter %.bpf.c,$^) -o $@
 
-LINKED_SKELS := xdp_redirect_cpu.skel.h xdp_redirect_map_multi.skel.h \
-		xdp_redirect_map.skel.h xdp_redirect.skel.h xdp_monitor.skel.h \
-		xdp_router_ipv4.skel.h
+LINKED_SKELS := xdp_router_ipv4.skel.h
 clean-files += $(LINKED_SKELS)
 
-xdp_redirect_cpu.skel.h-deps := xdp_redirect_cpu.bpf.o xdp_sample.bpf.o
-xdp_redirect_map_multi.skel.h-deps := xdp_redirect_map_multi.bpf.o xdp_sample.bpf.o
-xdp_redirect_map.skel.h-deps := xdp_redirect_map.bpf.o xdp_sample.bpf.o
-xdp_redirect.skel.h-deps := xdp_redirect.bpf.o xdp_sample.bpf.o
-xdp_monitor.skel.h-deps := xdp_monitor.bpf.o xdp_sample.bpf.o
 xdp_router_ipv4.skel.h-deps := xdp_router_ipv4.bpf.o xdp_sample.bpf.o
 
 LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))

samples/bpf/README.rst

@@ -4,6 +4,12 @@ eBPF sample programs
 This directory contains a test stubs, verifier test-suite and examples
 for using eBPF. The examples use libbpf from tools/lib/bpf.
 
+Note that the XDP-specific samples have been removed from this directory and
+moved to the xdp-tools repository: https://github.com/xdp-project/xdp-tools
+See the commit messages removing each tool from this directory for how to
+convert specific command invocations between the old samples and the utilities
+in xdp-tools.
+
 Build dependencies
 ==================