rtla: Add optional dependency on BPF tooling

If tooling required for building BPF CO-RE skeletons is present (that
is, libbpf, clang with BPF CO-RE support, and bpftool), turn on
HAVE_BPF_SKEL flag.

Those requirements are similar to what perf requires, with the
difference of using system libbpf and bpftool instead of in-tree
versions.

rtla can be forcefully built without BPF skeleton support by setting
BUILD_BPF_SKEL=0 manually; in that case, a warning is displayed.

Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Link: https://lore.kernel.org/20250218145859.27762-4-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

diff --git a/tools/tracing/rtla/Makefile b/tools/tracing/rtla/Makefile
index 8b5101457c70b48e9c720f1ba53293f1307c15a2..0aa116f7b355d1f8841acfc11a61519194cf1b77 100644 (file)
--- a/tools/tracing/rtla/Makefile
+++ b/tools/tracing/rtla/Makefile
@@ -33,9 +33,15 @@ DOCSRC               := ../../../Documentation/tools/rtla/
 FEATURE_TESTS  := libtraceevent
 FEATURE_TESTS  += libtracefs
 FEATURE_TESTS  += libcpupower
+FEATURE_TESTS  += libbpf
+FEATURE_TESTS  += clang-bpf-co-re
+FEATURE_TESTS  += bpftool-skeletons
 FEATURE_DISPLAY        := libtraceevent
 FEATURE_DISPLAY        += libtracefs
 FEATURE_DISPLAY        += libcpupower
+FEATURE_DISPLAY        += libbpf
+FEATURE_DISPLAY        += clang-bpf-co-re
+FEATURE_DISPLAY        += bpftool-skeletons
 
 ifeq ($(V),1)
   Q            =

diff --git a/tools/tracing/rtla/Makefile.config b/tools/tracing/rtla/Makefile.config
index 92a6e12e42d3a8af8022f62e742dd677a8f6376a..5f2231d8d62666b72c53686d6118567589cb02ae 100644 (file)
--- a/tools/tracing/rtla/Makefile.config
+++ b/tools/tracing/rtla/Makefile.config
@@ -53,6 +53,48 @@ else
   $(info Please install libcpupower-dev/kernel-tools-libs-devel)
 endif
 
+ifndef BUILD_BPF_SKEL
+  # BPF skeletons are used to implement improved sample collection, enable
+  # them by default.
+  BUILD_BPF_SKEL := 1
+endif
+
+ifeq ($(BUILD_BPF_SKEL),0)
+  $(info BPF skeleton support disabled, building without BPF skeleton support.)
+endif
+
+$(call feature_check,libbpf)
+ifeq ($(feature-libbpf), 1)
+  $(call detected,CONFIG_LIBBPF)
+else
+  $(info libbpf is missing, building without BPF skeleton support.)
+  $(info Please install libbpf-dev/libbpf-devel)
+  BUILD_BPF_SKEL := 0
+endif
+
+$(call feature_check,clang-bpf-co-re)
+ifeq ($(feature-clang-bpf-co-re), 1)
+  $(call detected,CONFIG_CLANG_BPF_CO_RE)
+else
+  $(info clang is missing or does not support BPF CO-RE, building without BPF skeleton support.)
+  $(info Please install clang)
+  BUILD_BPF_SKEL := 0
+endif
+
+$(call feature_check,bpftool-skeletons)
+ifeq ($(feature-bpftool-skeletons), 1)
+  $(call detected,CONFIG_BPFTOOL_SKELETONS)
+else
+  $(info bpftool is missing or not supporting skeletons, building without BPF skeleton support.)
+  $(info Please install bpftool)
+  BUILD_BPF_SKEL := 0
+endif
+
+ifeq ($(BUILD_BPF_SKEL),1)
+  CFLAGS += -DHAVE_BPF_SKEL
+  EXTLIBS += -lbpf
+endif
+
 ifeq ($(STOP_ERROR),1)
   $(error Please, check the errors above.)
 endif