Makefile: set BPF2GO_ environment vars ambiently, remove from go:gene…

…rate This patch removes the -cc and -cflags from all 'go:generate' statements across the codebase. Instead, ambiently provide BPF2GO_ env vars to the 'make' call in container-all. This allows running `go generate ./...` on distributions where clang binaries don't have their version numbers suffixed. Signed-off-by: Timo Beckers <timo@isovalent.com>
cilium · Sep 27, 2023 · 0667fa5 · 0667fa5
1 parent 4f779f5
commit 0667fa5
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Showing 14 changed files with 21 additions and 31 deletions.
diff --git a/Makefile b/Makefile
@@ -62,7 +62,7 @@ container-all:
 		--env CFLAGS="-fdebug-prefix-map=/ebpf=." \
 		--env HOME="/tmp" \
 		"${IMAGE}:${VERSION}" \
-		make all
+		make BPF2GO_CC="$(CLANG)" BPF2GO_FLAGS="$(CFLAGS)" all
 
 # (debug) Drop the user into a shell inside the container as root.
 container-shell:
@@ -81,9 +81,6 @@ all: format $(addsuffix -el.elf,$(TARGETS)) $(addsuffix -eb.elf,$(TARGETS)) gene
 	ln -srf testdata/loader-$(CLANG)-el.elf testdata/loader-el.elf
 	ln -srf testdata/loader-$(CLANG)-eb.elf testdata/loader-eb.elf
 
-# $BPF_CLANG is used in go:generate invocations.
-generate: export BPF_CLANG := $(CLANG)
-generate: export BPF_CFLAGS := $(CFLAGS)
 generate:
 	go generate ./...
 

diff --git a/cmd/bpf2go/README.md b/cmd/bpf2go/README.md
@@ -15,13 +15,18 @@ This will emit `foo_bpfel.go` and `foo_bpfeb.go`, with types using `foo`
 as a stem. The two files contain compiled BPF for little and big
 endian systems, respectively.
 
+## Environment Variables
+
 You can use environment variables to affect all bpf2go invocations
 across a project, e.g. to set specific C flags:
 
-    //go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cflags "$BPF_CFLAGS" foo path/to/src.c
+    BPF2GO_FLAGS="-O2 -g -Wall -Werror $(CFLAGS)" go generate ./...
+
+Alternatively, by exporting `$BPF2GO_FLAGS` from your build system, you can
+control all builds from a single location.
 
-By exporting `$BPF_CFLAGS` from your build system you can then control
-all builds from a single location.
+Most bpf2go arguments can be controlled this way. See `bpf2go -h` for an
+up-to-date list.
 
 ## Generated types
 

diff --git a/cmd/bpf2go/test/doc.go b/cmd/bpf2go/test/doc.go
@@ -2,5 +2,4 @@
 // specific API.
 package test
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG test ../testdata/minimal.c
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go test ../testdata/minimal.c
diff --git a/examples/cgroup_skb/main.go b/examples/cgroup_skb/main.go
@@ -17,8 +17,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf cgroup_skb.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf cgroup_skb.c -- -I../headers
 
 func main() {
 	// Allow the current process to lock memory for eBPF resources.

diff --git a/examples/fentry/main.go b/examples/fentry/main.go
@@ -28,8 +28,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS -type event bpf fentry.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -type event bpf fentry.c -- -I../headers
 
 func main() {
 	stopper := make(chan os.Signal, 1)

diff --git a/examples/kprobe/main.go b/examples/kprobe/main.go
@@ -12,8 +12,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf kprobe.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf kprobe.c -- -I../headers
 
 const mapKey uint32 = 0
 

diff --git a/examples/kprobe_percpu/main.go b/examples/kprobe_percpu/main.go
@@ -12,8 +12,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf kprobe_percpu.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf kprobe_percpu.c -- -I../headers
 
 const mapKey uint32 = 0
 

diff --git a/examples/kprobepin/main.go b/examples/kprobepin/main.go
@@ -15,8 +15,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf kprobe_pin.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf kprobe_pin.c -- -I../headers
 
 const (
 	mapKey    uint32 = 0

diff --git a/examples/ringbuffer/main.go b/examples/ringbuffer/main.go
@@ -15,8 +15,7 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS -type event bpf ringbuffer.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -type event bpf ringbuffer.c -- -I../headers
 
 func main() {
 	// Name of the kernel function to trace.

diff --git a/examples/tcprtt/main.go b/examples/tcprtt/main.go
@@ -30,8 +30,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS -type event bpf tcprtt.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -type event bpf tcprtt.c -- -I../headers
 
 func main() {
 	stopper := make(chan os.Signal, 1)

diff --git a/examples/tcprtt_sockops/main.go b/examples/tcprtt_sockops/main.go
@@ -40,8 +40,7 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -tags "linux" -cc $BPF_CLANG -cflags $BPF_CFLAGS -type rtt_event bpf tcprtt_sockops.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -tags "linux" -type rtt_event bpf tcprtt_sockops.c -- -I../headers
 
 func main() {
 	stopper := make(chan os.Signal, 1)

diff --git a/examples/tracepoint_in_c/main.go b/examples/tracepoint_in_c/main.go
@@ -12,8 +12,7 @@ import (
 	"github.com/cilium/ebpf/rlimit"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf tracepoint.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf tracepoint.c -- -I../headers
 
 const mapKey uint32 = 0
 

diff --git a/examples/uretprobe/main.go b/examples/uretprobe/main.go
@@ -21,8 +21,7 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS -target amd64 -type event bpf uretprobe.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -target amd64 -type event bpf uretprobe.c -- -I../headers
 
 const (
 	// The path to the ELF binary containing the function to trace.

diff --git a/examples/xdp/main.go b/examples/xdp/main.go
@@ -20,8 +20,7 @@ import (
 	"github.com/cilium/ebpf/link"
 )
 
-// $BPF_CLANG and $BPF_CFLAGS are set by the Makefile.
-//go:generate go run github.com/cilium/ebpf/cmd/bpf2go -cc $BPF_CLANG -cflags $BPF_CFLAGS bpf xdp.c -- -I../headers
+//go:generate go run github.com/cilium/ebpf/cmd/bpf2go bpf xdp.c -- -I../headers
 
 func main() {
 	if len(os.Args) < 2 {