Update ratelimiting build to use kernel version v5.15

.github/workflows/ci-build-ratelimiting.yaml

@@ -9,7 +9,7 @@ jobs:
   ratelimiting-build-ubuntu:
     runs-on: ubuntu-latest
     container:
-      image: ubuntu:bionic 
+      image: ubuntu:focal
 
     steps:
       - name: Set up build environment
@@ -48,9 +48,11 @@ jobs:
 
       - name: Clone dependencies 
         run: |
-          git clone --branch v5.1 --depth 1 https://github.com/torvalds/linux.git $LINUX_SRC_PATH
+          git clone --branch v5.15 --depth 1 https://github.com/torvalds/linux.git $LINUX_SRC_PATH
           cd $LINUX_SRC_PATH
           make defconfig
+          make prepare
+          make headers_install
 
       - name: Clone kernel function repository
         uses: actions/checkout@v2

ratelimiting/Makefile

@@ -5,104 +5,205 @@ BPF_SAMPLES_PATH := $(LINUX_SRC_PATH)/samples/bpf
 TOOLS_PATH := $(BPF_SAMPLES_PATH)/../../tools
 L3AF_SRC_PATH := $(CURDIR)
 
-# List of programs to build
-hostprogs-y := ratelimiting
-
 # Libbpf dependencies
 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
+# Tell kbuild to always build the programs
+always-y := $(tprogs-y)
+always-y += ratelimiting_kern.o
 
-ratelimiting-objs := ratelimiting_user.o ../../bpf_load.o
 
-# Tell kbuild to always build the programs
-always := $(hostprogs-y)
-always += ratelimiting_kern.o
+ifeq ($(ARCH), arm)
+# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux
+# headers when arm instruction set identification is requested.
+ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS))
+BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR)
+TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR)
+endif
+
+ifeq ($(ARCH), mips)
+TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__
+ifdef CONFIG_MACH_LOONGSON64
+BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64
+BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic
+endif
+endif
 
-KBUILD_HOSTCFLAGS += -I$(objtree)/usr/include
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib/
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/lib/ -I$(srctree)/tools/include -I$(srctree)/tools/include/uapi
-KBUILD_HOSTCFLAGS += -I$(srctree)/tools/perf
+TPROGS_CFLAGS += -Wall -O2
+TPROGS_CFLAGS += -Wmissing-prototypes
+TPROGS_CFLAGS += -Wstrict-prototypes
 
-HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable
-HOSTCFLAGS_trace_helpers.o += -I$(srctree)/tools/lib/bpf/
+TPROGS_CFLAGS += -I$(objtree)/usr/include
+TPROGS_CFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
+TPROGS_CFLAGS += -I$(srctree)/tools/lib/
+TPROGS_CFLAGS += -I$(srctree)/tools/include
+TPROGS_CFLAGS += -I$(srctree)/tools/perf
+TPROGS_CFLAGS += -DHAVE_ATTR_TEST=0
 
-HOSTCFLAGS_ratelimiting_user.o +=  -I. -I$(BPF_SAMPLES_PATH) -I$(srctree)/tools/lib/bpf/ -g -LTEST/libbpf.a
+ifdef SYSROOT
+TPROGS_CFLAGS += --sysroot=$(SYSROOT)
+TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib
+endif
 
-KBUILD_HOSTLDLIBS               += $(LIBBPF) -lelf
-HOSTLDLIBS_test_overhead        += -lrt
+TPROGS_LDLIBS			+= $(LIBBPF) -lelf -lz
 
+# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
+# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang
 LLC ?= llc
 CLANG ?= clang
+OPT ?= opt
+LLVM_DIS ?= llvm-dis
 LLVM_OBJCOPY ?= llvm-objcopy
 BTF_PAHOLE ?= pahole
 
 # Detect that we're cross compiling and use the cross compiler
 ifdef CROSS_COMPILE
-HOSTCC = $(CROSS_COMPILE)gcc
-CLANG_ARCH_ARGS = -target $(ARCH)
+CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%))
+endif
+
+# Don't evaluate probes and warnings if we need to run make recursively
+ifneq ($(src),)
+HDR_PROBE := $(shell printf "\#include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \
+	$(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \
+	-o /dev/null 2>/dev/null && echo okay)
+
+ifeq ($(HDR_PROBE),)
+$(warning WARNING: Detected possible issues with include path.)
+$(warning WARNING: Please install kernel headers locally (make headers_install).)
+endif
+
+BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
+BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
+BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
+BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
+			  $(CLANG) -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
+			  readelf -S ./llvm_btf_verify.o | grep BTF; \
+			  /bin/rm -f ./llvm_btf_verify.o)
+
+BPF_EXTRA_CFLAGS += -fno-stack-protector
+ifneq ($(BTF_LLVM_PROBE),)
+	BPF_EXTRA_CFLAGS += -g
+else
+ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
+	BPF_EXTRA_CFLAGS += -g
+	LLC_FLAGS += -mattr=dwarfris
+	DWARF2BTF = y
+endif
+endif
 endif
 
 # Trick to allow make to be run from this directory
 all:build tar.zip
+build:
+	$(MAKE) -C $(LINUX_SRC_PATH) M=$(L3AF_SRC_PATH)
+
 tar.zip:
 	@rm -rf l3af_ratelimiting
 	@rm -f l3af_ratelimiting.tar.gz
 	@mkdir l3af_ratelimiting
 	@cp $(L3AF_SRC_PATH)/ratelimiting_kern.o l3af_ratelimiting/
-	@cp $(L3AF_SRC_PATH)/ratelimiting l3af_ratelimiting/
 	@tar -cvf l3af_ratelimiting.tar ./l3af_ratelimiting
 	@gzip l3af_ratelimiting.tar
 
-build: $(LIBBPF)
-	$(MAKE) -C $(LINUX_SRC_PATH)/ $(L3AF_SRC_PATH)/ BPF_SAMPLES_PATH=$(BPF_SAMPLES_PATH)
 clean:
-	$(MAKE) -C $(LINUX_SRC_PATH) M=$(L3AF_SRC_PATH)/ clean
-	@rm -f ../*.o
-	@rm -f *~
+	$(MAKE) -C $(LINUX_SRC_PATH) M=$(L3AF_SRC_PATH) clean
+	@find $(CURDIR) -type f -name '*~' -delete
+	@rm -f ./*.o
 	@rm -f l3af_ratelimiting.tar.gz
 
 $(LIBBPF): FORCE
-
 # Fix up variables inherited from Kbuild that tools/ build system won't like
 	$(MAKE) -C $(dir $@) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \
 		LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(BPF_SAMPLES_PATH)/../../ O=
 
+BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool
+BPFTOOL := $(BPFTOOLDIR)/bpftool
+$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)
+	    $(MAKE) -C $(BPFTOOLDIR) srctree=$(BPF_SAMPLES_PATH)/../../
+
+$(obj)/syscall_nrs.h:	$(obj)/syscall_nrs.s FORCE
+	$(call filechk,offsets,__SYSCALL_NRS_H__)
+
+targets += syscall_nrs.s
+clean-files += syscall_nrs.h
+
 FORCE:
 
+
 # Verify LLVM compiler tools are available and bpf target is supported by llc
 .PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)
 
-#verify_cmds: $(CLANG) $(LLC)
+verify_cmds: $(CLANG) $(LLC)
 	@for TOOL in $^ ; do \
-                if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
-                        echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
-                        exit 1; \
-                else true; fi; \
-        done
+		if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
+			echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
+			exit 1; \
+		else true; fi; \
+	done
 
-#verify_target_bpf: verify_cmds
+verify_target_bpf: verify_cmds
 	@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
-                echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
-                echo "   NOTICE: LLVM version >= 3.7.1 required" ;\
-                exit 2; \
-        else true; fi
+		echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
+		echo "   NOTICE: LLVM version >= 3.7.1 required" ;\
+		exit 2; \
+	else true; fi
 
 $(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF)
 $(src)/*.c: verify_target_bpf $(LIBBPF)
 
-$(obj)/%.o: $(src)/%.c 
-	$(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
-		-I$(srctree)/tools/testing/selftests/bpf/ \
+
+-include $(BPF_SAMPLES_PATH)/Makefile.target
+
+VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux))				\
+		     $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux))	\
+		     $(abspath ./vmlinux)
+VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
+
+clean-files += vmlinux.h
+
+# Get Clang's default includes on this system, as opposed to those seen by
+# '-target bpf'. This fixes "missing" files on some architectures/distros,
+# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc.
+#
+# Use '-idirafter': Don't interfere with include mechanics except where the
+# build would have failed anyways.
+define get_sys_includes
+$(shell $(1) -v -E - </dev/null 2>&1 \
+        | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \
+$(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/')
+endef
+
+CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
+
+
+$(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
+	@echo "  CLANG-BPF " $@
+	$(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(SRCARCH) \
+		-Wno-compare-distinct-pointer-types -I$(srctree)/include \
+		-I$(srctree)/samples/bpf -I$(srctree)/tools/include \
+		-I$(srctree)/tools/lib -I$(srctree)/tools/lib/bpf $(CLANG_SYS_INCLUDES) \
+		-c $(filter %.bpf.c,$^) -o $@
+
+# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
+# But, there is no easy way to fix it, so just exclude it since it is
+# useless for BPF samples.
+# below we use long chain of commands, clang | opt | llvm-dis | llc,
+# to generate final object file. 'clang' compiles the source into IR
+# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin
+# processing (llvm12) and IR optimizations. 'llvm-dis' converts
+# 'opt' output to IR, and finally 'llc' generates bpf byte code.
+$(obj)/%.o: $(src)/%.c
+	@echo "  CLANG-bpf " $@
+	$(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \
+		-I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \
+		-I$(srctree)/tools/lib/ -I$(srctree)/tools/lib/bpf \
 		-D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \
-		-D__TARGET_ARCH_$(ARCH) -Wno-compare-distinct-pointer-types \
+		-D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \
 		-Wno-gnu-variable-sized-type-not-at-end \
 		-Wno-address-of-packed-member -Wno-tautological-compare \
-		-Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
-		-I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
-		-O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@
-ifeq ($(DWARF2BTF),y)
-	$(BTF_PAHOLE) -J $@
-endif
+                -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \
+                -fno-asynchronous-unwind-tables \
+                -I$(srctree)/samples/bpf/ -include asm_goto_workaround.h \
+                -O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \
+                $(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \
+                $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@