tools/runqslower: Fix LDFLAGS and add LDLIBS support

Actually use previously defined LDFLAGS during build and add support for
LDLIBS to link extra standalone libraries e.g. 'argp' which is not provided
by musl libc.

Fixes: 585bf4640ebe ("tools: runqslower: Add EXTRA_CFLAGS and EXTRA_LDFLAGS support")
Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20240723003045.2273499-1-tony.ambardar@gmail.com

diff --git a/tools/bpf/runqslower/Makefile b/tools/bpf/runqslower/Makefile
index d8288936c9120f11e36de1481b02eba27c18f153..c4f1f1735af659c2e660a322dbf6912d9a5724bc 100644 (file)
--- a/tools/bpf/runqslower/Makefile
+++ b/tools/bpf/runqslower/Makefile
@@ -15,6 +15,7 @@ INCLUDES := -I$(OUTPUT) -I$(BPF_INCLUDE) -I$(abspath ../../include/uapi)
 CFLAGS := -g -Wall $(CLANG_CROSS_FLAGS)
 CFLAGS += $(EXTRA_CFLAGS)
 LDFLAGS += $(EXTRA_LDFLAGS)
+LDLIBS += -lelf -lz
 
 # Try to detect best kernel BTF source
 KERNEL_REL := $(shell uname -r)
@@ -51,7 +52,7 @@ clean:
 libbpf_hdrs: $(BPFOBJ)
 
 $(OUTPUT)/runqslower: $(OUTPUT)/runqslower.o $(BPFOBJ)
-       $(QUIET_LINK)$(CC) $(CFLAGS) $^ -lelf -lz -o $@
+       $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $^ $(LDLIBS) -o $@
 
 $(OUTPUT)/runqslower.o: runqslower.h $(OUTPUT)/runqslower.skel.h             \
                        $(OUTPUT)/runqslower.bpf.o | libbpf_hdrs