From 064bc313542022e0131f98064ab5e1f73164af55 Mon Sep 17 00:00:00 2001
From: Jesper Dangaard Brouer <brouer@redhat.com>
Date: Tue, 1 Jun 2021 16:12:43 +0200
Subject: [PATCH] headers/vmlinux: Add arch specific vmlinux.h defines

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 headers/vmlinux/arch/x86/vmlinux.h | 29 +++++++++++++++++++++++++++++
 headers/vmlinux_local.h            | 20 ++++++++++++++++----
 ktrace-CO-RE/Makefile              |  4 ----
 lib/common.mk                      |  7 +++++++
 4 files changed, 52 insertions(+), 8 deletions(-)
 create mode 100644 headers/vmlinux/arch/x86/vmlinux.h

diff --git a/headers/vmlinux/arch/x86/vmlinux.h b/headers/vmlinux/arch/x86/vmlinux.h
new file mode 100644
index 0000000..d02ec90
--- /dev/null
+++ b/headers/vmlinux/arch/x86/vmlinux.h
@@ -0,0 +1,29 @@
+#ifndef __VMLINUX_ARCH_X86_H__
+#define __VMLINUX_ARCH_X86_H__
+
+
+struct pt_regs {
+	long unsigned int r15;
+	long unsigned int r14;
+	long unsigned int r13;
+	long unsigned int r12;
+	long unsigned int bp;
+	long unsigned int bx;
+	long unsigned int r11;
+	long unsigned int r10;
+	long unsigned int r9;
+	long unsigned int r8;
+	long unsigned int ax;
+	long unsigned int cx;
+	long unsigned int dx;
+	long unsigned int si;
+	long unsigned int di;
+	long unsigned int orig_ax;
+	long unsigned int ip;
+	long unsigned int cs;
+	long unsigned int flags;
+	long unsigned int sp;
+	long unsigned int ss;
+};
+
+#endif /* __VMLINUX_ARCH_X86_H__ */
diff --git a/headers/vmlinux_local.h b/headers/vmlinux_local.h
index 6c03fab..53a63e0 100644
--- a/headers/vmlinux_local.h
+++ b/headers/vmlinux_local.h
@@ -9,10 +9,6 @@
  */
 #ifndef __VMLINUX_H__
 #define __VMLINUX_H__
-/*
- * Notice: Defining __VMLINUX_H__ (or __KERNEL__) cause <bpf/bpf_tracing.h>
- *         header file to define architecture specific PT_REGS_PARM's.
- */
 
 #include <linux/types.h> /* Needed for __uNN in vmlinux/vmlinux_types.h */
 
@@ -24,6 +20,22 @@
 #include "vmlinux/vmlinux_common.h"
 #include "vmlinux/vmlinux_net.h"
 
+/*
+ * Notice: Defining __VMLINUX_H__ (or __KERNEL__) cause <bpf/bpf_tracing.h>
+ *         header file to define architecture specific PT_REGS_PARM's.
+ *
+ * When using '-target bpf' the fallback mechanism doesn't detect right arch
+ * via  compiler defines.
+ *
+ * Makefile system in lib/common.mk detect ARCH and defines the
+ * defines __TARGET_ARCH_$(ARCH) matched on below.
+ */
+#if defined(__TARGET_ARCH_x86)
+#include "vmlinux/arch/x86/vmlinux.h"
+#else
+#warning "Makefile for BPF-tracing on this arch: not supported yet"
+#endif
+
 #ifndef BPF_NO_PRESERVE_ACCESS_INDEX
 #pragma clang attribute pop
 #endif
diff --git a/ktrace-CO-RE/Makefile b/ktrace-CO-RE/Makefile
index f90ed0a..3c69d6c 100644
--- a/ktrace-CO-RE/Makefile
+++ b/ktrace-CO-RE/Makefile
@@ -1,9 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-# The BPF tracing header (/usr/include/bpf/bpf_tracing.h) need to know
-# CPU architecture due to PT_REGS_PARM resolution of ASM call convention
-ARCH := $(shell uname -m | sed 's/x86_64/x86/' | sed 's/aarch64/arm64/' | sed 's/ppc64le/powerpc/' | sed 's/mips.*/mips/')
-
 USER_TARGETS := ktrace01
 BPF_TARGETS  := ktrace01_kern
 
diff --git a/lib/common.mk b/lib/common.mk
index 2719d98..798d632 100644
--- a/lib/common.mk
+++ b/lib/common.mk
@@ -33,6 +33,13 @@ ifeq ($(SYSTEM_LIBBPF),n)
 	LIBBPF_SOURCES := $(wildcard $(LIBBPF_DIR)/src/*.[ch])
 endif
 
+# The BPF tracing header (/usr/include/bpf/bpf_tracing.h) need to know
+# CPU architecture due to PT_REGS_PARM resolution of ASM call convention
+#
+ARCH := $(shell uname -m | sed 's/x86_64/x86/' | sed 's/aarch64/arm64/' | sed 's/ppc64le/powerpc/' | sed 's/mips.*/mips/')
+
+BPF_CFLAGS += -D__TARGET_ARCH_$(ARCH)
+
 # BPF-prog kern and userspace shares struct via header file:
 KERN_USER_H ?= $(wildcard common_kern_user.h)