summaryrefslogtreecommitdiff
path: root/tools/lib/bpf
diff options
context:
space:
mode:
authorBrian Norris <briannorris@chromium.org>2024-07-15 13:32:44 -0700
committerArnaldo Carvalho de Melo <acme@redhat.com>2024-08-05 12:19:48 -0300
commitdbb2a7a986971ef43d5a60d235c05491647e16f4 (patch)
tree07a926eb50058e2bef10955cc9be64c26bcf7715 /tools/lib/bpf
parentea974028a049f2cea4bb6be963ee3e3844a03f6d (diff)
tools build: Correct bpf fixdep dependencies
The dependencies in tools/lib/bpf/Makefile are incorrect. Before we recurse to build $(BPF_IN_STATIC), we need to build its 'fixdep' executable. I can't use the usual shortcut from Makefile.include: <target>: <sources> fixdep because its 'fixdep' target relies on $(OUTPUT), and $(OUTPUT) differs in the parent 'make' versus the child 'make' -- so I imitate it via open-coding. I tweak a few $(MAKE) invocations while I'm at it, because 1. I'm adding a new recursive make; and 2. these recursive 'make's print spurious lines about files that are "up to date" (which isn't normally a feature in Kbuild subtargets) or "jobserver not available" (see [1]) I also need to tweak the assignment of the OUTPUT variable, so that relative path builds work. For example, for 'make tools/lib/bpf', OUTPUT is unset, and is usually treated as "cwd" -- but recursive make will change cwd and so OUTPUT has a new meaning. For consistency, I ensure OUTPUT is always an absolute path. And $(Q) gets a backup definition in tools/build/Makefile.include, because Makefile.include is sometimes included without tools/build/Makefile, so the "quiet command" stuff doesn't actually work consistently without it. After this change, top-level builds result in an empty grep result from: $ grep 'cannot find fixdep' $(find tools/ -name '*.cmd') [1] https://www.gnu.org/software/make/manual/html_node/MAKE-Variable.html If we're not using $(MAKE) directly, then we need to use more '+'. Signed-off-by: Brian Norris <briannorris@chromium.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Richter <tmricht@linux.ibm.com> Link: https://lore.kernel.org/r/20240715203325.3832977-4-briannorris@chromium.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/lib/bpf')
-rw-r--r--tools/lib/bpf/.gitignore1
-rw-r--r--tools/lib/bpf/Makefile13
2 files changed, 11 insertions, 3 deletions
diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore
index 0da84cb9e66d..f02725b123b3 100644
--- a/tools/lib/bpf/.gitignore
+++ b/tools/lib/bpf/.gitignore
@@ -5,3 +5,4 @@ TAGS
tags
cscope.*
/bpf_helper_defs.h
+fixdep
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 2cf892774346..1b22f0f37288 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -108,6 +108,8 @@ MAKEOVERRIDES=
all:
+OUTPUT ?= ./
+OUTPUT := $(abspath $(OUTPUT))/
export srctree OUTPUT CC LD CFLAGS V
include $(srctree)/tools/build/Makefile.include
@@ -141,7 +143,10 @@ all: fixdep
all_cmd: $(CMD_TARGETS) check
-$(BPF_IN_SHARED): force $(BPF_GENERATED)
+$(SHARED_OBJDIR) $(STATIC_OBJDIR):
+ $(Q)mkdir -p $@
+
+$(BPF_IN_SHARED): force $(BPF_GENERATED) | $(SHARED_OBJDIR)
@(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true
@@ -151,9 +156,11 @@ $(BPF_IN_SHARED): force $(BPF_GENERATED)
@(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && ( \
(diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) || \
echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true
+ $(SILENT_MAKE) -C $(srctree)/tools/build CFLAGS= LDFLAGS= OUTPUT=$(SHARED_OBJDIR) $(SHARED_OBJDIR)fixdep
$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"
-$(BPF_IN_STATIC): force $(BPF_GENERATED)
+$(BPF_IN_STATIC): force $(BPF_GENERATED) | $(STATIC_OBJDIR)
+ $(SILENT_MAKE) -C $(srctree)/tools/build CFLAGS= LDFLAGS= OUTPUT=$(STATIC_OBJDIR) $(STATIC_OBJDIR)fixdep
$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)
$(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
@@ -263,7 +270,7 @@ install_pkgconfig: $(PC_FILE)
install: install_lib install_pkgconfig install_headers
-clean:
+clean: fixdep-clean
$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS) \
*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_GENERATED) \
$(SHARED_OBJDIR) $(STATIC_OBJDIR) \