libbpf: Complete powerpc spec in bpf_tracing.h

Add definitions of PARM6 through PARM8 for powerpc architecture. Add
also a link to a functiona call sequence documentation for future reference.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230120200914.3008030-6-andrii@kernel.org

diff --git a/tools/lib/bpf/bpf_tracing.h b/tools/lib/bpf/bpf_tracing.h
index f356955..1b9447f 100644 (file)
--- a/tools/lib/bpf/bpf_tracing.h
+++ b/tools/lib/bpf/bpf_tracing.h
@@ -222,11 +222,19 @@ struct pt_regs___arm64 {
 
 #elif defined(bpf_target_powerpc)
 
+/*
+ * http://refspecs.linux-foundation.org/elf/elfspec_ppc.pdf (page 3-14,
+ * section "Function Calling Sequence")
+ */
+
 #define __PT_PARM1_REG gpr[3]
 #define __PT_PARM2_REG gpr[4]
 #define __PT_PARM3_REG gpr[5]
 #define __PT_PARM4_REG gpr[6]
 #define __PT_PARM5_REG gpr[7]
+#define __PT_PARM6_REG gpr[8]
+#define __PT_PARM7_REG gpr[9]
+#define __PT_PARM8_REG gpr[10]
 #define __PT_RET_REG regs[31]
 #define __PT_FP_REG __unsupported__
 #define __PT_RC_REG gpr[3]