From a5d0c26a2784890d803fca5e0dd27c590472b43d Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 27 Jul 2023 18:12:50 -0700 Subject: selftests/bpf: Add a cpuv4 test runner for cpu=v4 testing Similar to no-alu32 runner, if clang compiler supports -mcpu=v4, a cpuv4 runner is created to test bpf programs compiled with -mcpu=v4. The following are some num-of-insn statistics for each newer instructions based on existing selftests, excluding subsequent cpuv4 insn specific tests. insn pattern # of instructions reg = (s8)reg 4 reg = (s16)reg 4 reg = (s32)reg 144 reg = *(s8 *)(reg + off) 13 reg = *(s16 *)(reg + off) 14 reg = *(s32 *)(reg + off) 15215 reg = bswap16 reg 142 reg = bswap32 reg 38 reg = bswap64 reg 14 reg s/= reg 0 reg s%= reg 0 gotol 58 Note that in llvm -mcpu=v4 implementation, the compiler is a little bit conservative about generating 'gotol' insn (32-bit branch offset) as it didn't precise count the number of insns (e.g., some insns are debug insns, etc.). Compared to old 'goto' insn, newer 'gotol' insn should have comparable verification states to 'goto' insn. With current patch set, all selftests passed with -mcpu=v4 when running test_progs-cpuv4 binary. The -mcpu=v3 and -mcpu=v2 run are also successful. Signed-off-by: Yonghong Song Link: https://lore.kernel.org/r/20230728011250.3718252-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov --- tools/testing/selftests/bpf/.gitignore | 2 ++ tools/testing/selftests/bpf/Makefile | 28 ++++++++++++++++++++++++---- 2 files changed, 26 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore index 116fecf80ca1..110518ba4804 100644 --- a/tools/testing/selftests/bpf/.gitignore +++ b/tools/testing/selftests/bpf/.gitignore @@ -13,6 +13,7 @@ test_dev_cgroup /test_progs /test_progs-no_alu32 /test_progs-bpf_gcc +/test_progs-cpuv4 test_verifier_log feature test_sock @@ -36,6 +37,7 @@ test_cpp *.lskel.h /no_alu32 /bpf_gcc +/cpuv4 /host-tools /tools /runqslower diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 882be03b179f..6a45719a8d47 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -33,9 +33,13 @@ CFLAGS += -g -O0 -rdynamic -Wall -Werror $(GENFLAGS) $(SAN_CFLAGS) \ LDFLAGS += $(SAN_LDFLAGS) LDLIBS += -lelf -lz -lrt -lpthread -# Silence some warnings when compiled with clang ifneq ($(LLVM),) +# Silence some warnings when compiled with clang CFLAGS += -Wno-unused-command-line-argument +# Check whether cpu=v4 is supported or not by clang +ifneq ($(shell $(CLANG) --target=bpf -mcpu=help 2>&1 | grep 'v4'),) +CLANG_CPUV4 := 1 +endif endif # Order correspond to 'make run_tests' order @@ -51,6 +55,10 @@ ifneq ($(BPF_GCC),) TEST_GEN_PROGS += test_progs-bpf_gcc endif +ifneq ($(CLANG_CPUV4),) +TEST_GEN_PROGS += test_progs-cpuv4 +endif + TEST_GEN_FILES = test_lwt_ip_encap.bpf.o test_tc_edt.bpf.o TEST_FILES = xsk_prereqs.sh $(wildcard progs/btf_dump_test_case_*.c) @@ -383,6 +391,11 @@ define CLANG_NOALU32_BPF_BUILD_RULE $(call msg,CLNG-BPF,$(TRUNNER_BINARY),$2) $(Q)$(CLANG) $3 -O2 --target=bpf -c $1 -mcpu=v2 -o $2 endef +# Similar to CLANG_BPF_BUILD_RULE, but with cpu-v4 +define CLANG_CPUV4_BPF_BUILD_RULE + $(call msg,CLNG-BPF,$(TRUNNER_BINARY),$2) + $(Q)$(CLANG) $3 -O2 --target=bpf -c $1 -mcpu=v4 -o $2 +endef # Build BPF object using GCC define GCC_BPF_BUILD_RULE $(call msg,GCC-BPF,$(TRUNNER_BINARY),$2) @@ -425,7 +438,7 @@ LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.c,$(foreach skel,$(LINKED_SKELS),$($(ske # $eval()) and pass control to DEFINE_TEST_RUNNER_RULES. # Parameters: # $1 - test runner base binary name (e.g., test_progs) -# $2 - test runner extra "flavor" (e.g., no_alu32, gcc-bpf, etc) +# $2 - test runner extra "flavor" (e.g., no_alu32, cpuv4, gcc-bpf, etc) define DEFINE_TEST_RUNNER TRUNNER_OUTPUT := $(OUTPUT)$(if $2,/)$2 @@ -453,7 +466,7 @@ endef # Using TRUNNER_XXX variables, provided by callers of DEFINE_TEST_RUNNER and # set up by DEFINE_TEST_RUNNER itself, create test runner build rules with: # $1 - test runner base binary name (e.g., test_progs) -# $2 - test runner extra "flavor" (e.g., no_alu32, gcc-bpf, etc) +# $2 - test runner extra "flavor" (e.g., no_alu32, cpuv4, gcc-bpf, etc) define DEFINE_TEST_RUNNER_RULES ifeq ($($(TRUNNER_OUTPUT)-dir),) @@ -584,6 +597,13 @@ TRUNNER_BPF_BUILD_RULE := CLANG_NOALU32_BPF_BUILD_RULE TRUNNER_BPF_CFLAGS := $(BPF_CFLAGS) $(CLANG_CFLAGS) $(eval $(call DEFINE_TEST_RUNNER,test_progs,no_alu32)) +# Define test_progs-cpuv4 test runner. +ifneq ($(CLANG_CPUV4),) +TRUNNER_BPF_BUILD_RULE := CLANG_CPUV4_BPF_BUILD_RULE +TRUNNER_BPF_CFLAGS := $(BPF_CFLAGS) $(CLANG_CFLAGS) +$(eval $(call DEFINE_TEST_RUNNER,test_progs,cpuv4)) +endif + # Define test_progs BPF-GCC-flavored test runner. ifneq ($(BPF_GCC),) TRUNNER_BPF_BUILD_RULE := GCC_BPF_BUILD_RULE @@ -681,7 +701,7 @@ EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) $(HOST_SCRATCH_DIR) \ prog_tests/tests.h map_tests/tests.h verifier/tests.h \ feature bpftool \ $(addprefix $(OUTPUT)/,*.o *.skel.h *.lskel.h *.subskel.h \ - no_alu32 bpf_gcc bpf_testmod.ko \ + no_alu32 cpuv4 bpf_gcc bpf_testmod.ko \ liburandom_read.so) .PHONY: docs docs-clean -- cgit