Update LLVM-BPF and a script to compile BPF MPTCP scheduler

common/include/bpf_mptcp.mk

@@ -0,0 +1,94 @@
+include $(INCLUDE_DIR)/kernel.mk
+
+BPF_DEPENDS := @HAS_BPF_TOOLCHAIN
+LLVM_VER:=
+
+CLANG_MIN_VER:=12
+
+ifneq ($(CONFIG_USE_LLVM_HOST),)
+  BPF_TOOLCHAIN_HOST_PATH:=$(call qstrip,$(CONFIG_BPF_TOOLCHAIN_HOST_PATH))
+  ifneq ($(BPF_TOOLCHAIN_HOST_PATH),)
+    BPF_PATH:=$(BPF_TOOLCHAIN_HOST_PATH)/bin:$(PATH)
+  else
+    BPF_PATH:=$(PATH)
+  endif
+  CLANG:=$(firstword $(shell PATH='$(BPF_PATH)' command -v clang clang-16 clang-13 clang-12 clang-11))
+  LLVM_VER:=$(subst clang,,$(notdir $(CLANG)))
+endif
+ifneq ($(CONFIG_USE_LLVM_PREBUILT),)
+  CLANG:=$(TOPDIR)/llvm-bpf/bin/clang
+endif
+ifneq ($(CONFIG_USE_LLVM_BUILD),)
+  CLANG:=$(STAGING_DIR_HOST)/llvm-bpf/bin/clang
+endif
+
+LLVM_PATH:=$(dir $(CLANG))
+LLVM_LLC:=$(LLVM_PATH)/llc$(LLVM_VER)
+LLVM_DIS:=$(LLVM_PATH)/llvm-dis$(LLVM_VER)
+LLVM_OPT:=$(LLVM_PATH)/opt$(LLVM_VER)
+LLVM_STRIP:=$(LLVM_PATH)/llvm-strip$(LLVM_VER)
+
+BPF_KARCH:=mips
+#BPF_KARCH:=$(LINUX_KARCH)
+BPF_ARCH:=mips$(if $(CONFIG_ARCH_64BIT),64)$(if $(CONFIG_BIG_ENDIAN),,el)
+#BPF_ARCH:=$(ARCH)
+BPF_TARGET:=bpf$(if $(CONFIG_BIG_ENDIAN),eb,el)
+
+BPF_HEADERS_DIR:=$(STAGING_DIR)/bpf-headers
+#BPF_HEADERS_DIR:=$(LINUX_DIR)
+
+BPF_KERNEL_INCLUDE := \
+        -nostdinc -isystem $(TOOLCHAIN_DIR)/include \
+        -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/generated \
+        -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/uapi \
+        -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/generated/uapi \
+        -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include \
+        -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/asm/mach-generic \
+        -I$(BPF_HEADERS_DIR)/include/uapi \
+        -I$(BPF_HEADERS_DIR)/include/generated/uapi \
+        -I$(BPF_HEADERS_DIR)/tools/lib \
+        -I$(BPF_HEADERS_DIR)/tools/testing/selftests \
+        -I$(BPF_HEADERS_DIR)/samples/bpf \
+        -I$(BPF_HEADERS_DIR)/include \
+        -include asm-generic/int-ll64.h \
+        -include linux/kconfig.h
+#	-include asm_goto_workaround.h
+
+BPF_CFLAGS := \
+	$(BPF_KERNEL_INCLUDE) -I$(PKG_BUILD_DIR) \
+	-D__KERNEL__ -D__BPF_TRACING__ -DCONFIG_GENERIC_CSUM -DCONFIG_PAGE_SIZE_64KB \
+	-D__TARGET_ARCH_${BPF_KARCH} \
+	-D$(if $(CONFIG_BIG_ENDIAN),__MIPSEB__,__MIPSEL__) \
+	-m$(if $(CONFIG_BIG_ENDIAN),big,little)-endian \
+	-fno-stack-protector -Wall \
+	-Wno-unused-value -Wno-pointer-sign \
+	-Wno-compare-distinct-pointer-types \
+	-Wno-gnu-variable-sized-type-not-at-end \
+	-Wno-address-of-packed-member -Wno-tautological-compare \
+	-Wno-unknown-warning-option \
+	-fno-asynchronous-unwind-tables \
+	-Wno-uninitialized -Wno-unused-variable \
+	-Wno-unused-label \
+	-O2 -emit-llvm -Xclang -disable-llvm-passes
+
+ifneq ($(CONFIG_HAS_BPF_TOOLCHAIN),)
+ifeq ($(DUMP)$(filter download refresh,$(MAKECMDGOALS)),)
+#  CLANG_VER:=$(shell $(CLANG) -dM -E - < /dev/null | grep __clang_major__ | cut -d' ' -f3)
+  CLANG_VER:=$(shell $(CLANG) --version - < /dev/null | grep -oE '[0-9]+' | head -n 1)
+  CLANG_VER_VALID:=$(shell [ "$(CLANG_VER)" -ge "$(CLANG_MIN_VER)" ] && echo 1 )
+  ifeq ($(CLANG_VER_VALID),)
+    $(error ERROR: LLVM/clang version too old. Minimum required: $(CLANG_MIN_VER), found: $(CLANG_VER))
+  endif
+endif
+endif
+
+define CompileBPF
+	$(CLANG) -g --target=bpf $(BPF_CFLAGS) $(2) \
+		-c $(1) -o $(patsubst %.c,%.bc,$(1))
+	$(LLVM_OPT) -O2 -mtriple=$(BPF_TARGET) < $(patsubst %.c,%.bc,$(1)) > $(patsubst %.c,%.opt,$(1))
+	$(LLVM_DIS) < $(patsubst %.c,%.opt,$(1)) > $(patsubst %.c,%.S,$(1))
+	$(LLVM_LLC) -march=$(BPF_TARGET) -mcpu=v3 -filetype=obj -o $(patsubst %.c,%.o,$(1)) < $(patsubst %.c,%.S,$(1))
+	$(CP) $(patsubst %.c,%.o,$(1)) $(patsubst %.c,%.debug.o,$(1))
+	$(LLVM_STRIP) --strip-debug $(patsubst %.c,%.o,$(1))
+endef
+