From ef9985893caf905b769fae8984780847e8527065 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 13 Apr 2021 08:34:29 -0700 Subject: [PATCH] selftests/bpf: Silence clang compilation warnings With clang compiler: make -j60 LLVM=1 LLVM_IAS=1 <=== compile kernel make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 Some linker flags are not used/effective for some binaries and we have warnings like: warning: -lelf: 'linker' input unused [-Wunused-command-line-argument] We also have warnings like: .../selftests/bpf/prog_tests/ns_current_pid_tgid.c:74:57: note: treat the string as an argument to avoid this if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", strerror(errno))) ^ "%s", .../selftests/bpf/test_progs.h:129:35: note: expanded from macro 'CHECK' _CHECK(condition, tag, duration, format) ^ .../selftests/bpf/test_progs.h:108:21: note: expanded from macro '_CHECK' fprintf(stdout, ##format); \ ^ The first warning can be silenced with clang option -Wno-unused-command-line-argument. For the second warning, source codes are modified as suggested by the compiler to silence the warning. Since gcc does not support the option -Wno-unused-command-line-argument and the warning only happens with clang compiler, the option -Wno-unused-command-line-argument is enabled only when clang compiler is used. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210413153429.3029377-1-yhs@fb.com --- tools/testing/selftests/bpf/Makefile | 5 +++++ tools/testing/selftests/bpf/prog_tests/fexit_sleep.c | 4 ++-- tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c | 4 ++-- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index dcc2dc1..c45ae13 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -28,6 +28,11 @@ CFLAGS += -g -Og -rdynamic -Wall $(GENFLAGS) $(SAN_CFLAGS) \ -Dbpf_load_program=bpf_test_load_program LDLIBS += -lcap -lelf -lz -lrt -lpthread +# Silence some warnings when compiled with clang +ifneq ($(LLVM),) +CFLAGS += -Wno-unused-command-line-argument +endif + # Order correspond to 'make run_tests' order TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \ test_verifier_log test_dev_cgroup \ diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_sleep.c b/tools/testing/selftests/bpf/prog_tests/fexit_sleep.c index 6c4d42a..ccc7e8a 100644 --- a/tools/testing/selftests/bpf/prog_tests/fexit_sleep.c +++ b/tools/testing/selftests/bpf/prog_tests/fexit_sleep.c @@ -39,7 +39,7 @@ void test_fexit_sleep(void) goto cleanup; cpid = clone(do_sleep, child_stack + STACK_SIZE, CLONE_FILES | SIGCHLD, fexit_skel); - if (CHECK(cpid == -1, "clone", strerror(errno))) + if (CHECK(cpid == -1, "clone", "%s\n", strerror(errno))) goto cleanup; /* wait until first sys_nanosleep ends and second sys_nanosleep starts */ @@ -65,7 +65,7 @@ void test_fexit_sleep(void) /* kill the thread to unwind sys_nanosleep stack through the trampoline */ kill(cpid, 9); - if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", strerror(errno))) + if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", "%s\n", strerror(errno))) goto cleanup; if (CHECK(WEXITSTATUS(wstatus) != 0, "exitstatus", "failed")) goto cleanup; diff --git a/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c index 31a3114..2535788 100644 --- a/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c +++ b/tools/testing/selftests/bpf/prog_tests/ns_current_pid_tgid.c @@ -68,10 +68,10 @@ static void test_ns_current_pid_tgid_new_ns(void) cpid = clone(test_current_pid_tgid, child_stack + STACK_SIZE, CLONE_NEWPID | SIGCHLD, NULL); - if (CHECK(cpid == -1, "clone", strerror(errno))) + if (CHECK(cpid == -1, "clone", "%s\n", strerror(errno))) return; - if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", strerror(errno))) + if (CHECK(waitpid(cpid, &wstatus, 0) == -1, "waitpid", "%s\n", strerror(errno))) return; if (CHECK(WEXITSTATUS(wstatus) != 0, "newns_pidtgid", "failed")) -- 2.7.4