Fixed compilation issue

[simplyatul]

make in the chapter5 directory giving the following error.

[chapter5]# make
clang \
    -target bpf \
        -D __TARGET_ARCH_x86 \
    -Wall \
    -O2 -g -o hello-buffer-config.bpf.o -c hello-buffer-config.bpf.c
hello-buffer-config.bpf.c:27:5: error: no member named 'di' in 'struct pt_regs'
int BPF_KPROBE_SYSCALL(hello, const char *pathname)
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:920:28: note: expanded from macro 'BPF_KPROBE_SYSCALL'
#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
                           ^
/usr/include/bpf/bpf_tracing.h:907:31: note: expanded from macro 'BPF_KSYSCALL'
                               ? (struct pt_regs *)PT_REGS_PARM1(ctx)       \
                                                   ^~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:492:46: note: expanded from macro 'PT_REGS_PARM1'
#define PT_REGS_PARM1(x) (__PT_REGS_CAST(x)->__PT_PARM1_REG)
                          ~~~~~~~~~~~~~~~~~  ^
/usr/include/bpf/bpf_tracing.h:87:24: note: expanded from macro '__PT_PARM1_REG'
#define __PT_PARM1_REG di
                       ^
hello-buffer-config.bpf.c:27:5: error: no member named 'di' in 'struct pt_regs'
int BPF_KPROBE_SYSCALL(hello, const char *pathname)
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:920:28: note: expanded from macro 'BPF_KPROBE_SYSCALL'
#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
                           ^
/usr/include/bpf/bpf_tracing.h:912:21: note: expanded from macro 'BPF_KSYSCALL'
                return ____##name(___bpf_syswrap_args(args));               \
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:873:42: note: expanded from macro '___bpf_syswrap_args'
#define ___bpf_syswrap_args(args...)     ___bpf_apply(___bpf_syswrap_args, ___bpf_narg(args))(args)
                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: (skipping 8 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
/usr/include/bpf/bpf_core_read.h:391:38: note: expanded from macro '___type'
#define ___type(...) typeof(___arrow(__VA_ARGS__))
                            ~~~~~~~~~^~~~~~~~~~~~
/usr/include/bpf/bpf_core_read.h:389:64: note: expanded from macro '___arrow'
#define ___arrow(...) ___apply(___arrow, ___narg(__VA_ARGS__))(__VA_ARGS__)
                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
/usr/include/bpf/bpf_core_read.h:380:28: note: expanded from macro '___arrow2'
#define ___arrow2(a, b) a->b
                        ~  ^
hello-buffer-config.bpf.c:27:5: error: no member named 'di' in 'struct pt_regs'
int BPF_KPROBE_SYSCALL(hello, const char *pathname)
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:920:28: note: expanded from macro 'BPF_KPROBE_SYSCALL'
#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
                           ^
/usr/include/bpf/bpf_tracing.h:912:21: note: expanded from macro 'BPF_KSYSCALL'
                return ____##name(___bpf_syswrap_args(args));               \
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:873:42: note: expanded from macro '___bpf_syswrap_args'
#define ___bpf_syswrap_args(args...)     ___bpf_apply(___bpf_syswrap_args, ___bpf_narg(args))(args)
                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: (skipping 10 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
/usr/include/bpf/bpf_core_read.h:413:38: note: expanded from macro '___core_read0'
        ___read(fn, dst, ___type(src), src, a);
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~
/usr/include/bpf/bpf_core_read.h:394:61: note: expanded from macro '___read'
        read_fn((void *)(dst), sizeof(*(dst)), &((src_type)(src))->accessor)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~
/usr/include/bpf/bpf_core_read.h:312:79: note: expanded from macro 'bpf_core_read'
        bpf_probe_read_kernel(dst, sz, (const void *)__builtin_preserve_access_index(src))
                                                                                     ^~~
hello-buffer-config.bpf.c:27:5: error: operand of type 'void' where arithmetic or pointer type is required
int BPF_KPROBE_SYSCALL(hello, const char *pathname)
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:920:28: note: expanded from macro 'BPF_KPROBE_SYSCALL'
#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
                           ^
/usr/include/bpf/bpf_tracing.h:912:21: note: expanded from macro 'BPF_KSYSCALL'
                return ____##name(___bpf_syswrap_args(args));               \
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:873:42: note: expanded from macro '___bpf_syswrap_args'
#define ___bpf_syswrap_args(args...)     ___bpf_apply(___bpf_syswrap_args, ___bpf_narg(args))(args)
                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: (skipping 3 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
/usr/include/bpf/bpf_tracing.h:866:86: note: expanded from macro '___bpf_syswrap_args1'
#define ___bpf_syswrap_args1(x)          ___bpf_syswrap_args0(), (unsigned long long)PT_REGS_PARM1_CORE_SYSCALL(regs)
                                                                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:541:39: note: expanded from macro 'PT_REGS_PARM1_CORE_SYSCALL'
#define PT_REGS_PARM1_CORE_SYSCALL(x) BPF_CORE_READ(__PT_REGS_CAST(x), __PT_PARM1_SYSCALL_REG)
                                      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_core_read.h:519:36: note: expanded from macro 'BPF_CORE_READ'
#define BPF_CORE_READ(src, a, ...) ({                                       \
                                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
hello-buffer-config.bpf.c:27:5: error: no member named 'di' in 'struct pt_regs'
int BPF_KPROBE_SYSCALL(hello, const char *pathname)
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:920:28: note: expanded from macro 'BPF_KPROBE_SYSCALL'
#define BPF_KPROBE_SYSCALL BPF_KSYSCALL
                           ^
/usr/include/bpf/bpf_tracing.h:914:21: note: expanded from macro 'BPF_KSYSCALL'
                return ____##name(___bpf_syscall_args(args));               \
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/bpf/bpf_tracing.h:862:42: note: expanded from macro '___bpf_syscall_args'
#define ___bpf_syscall_args(args...)     ___bpf_apply(___bpf_syscall_args, ___bpf_narg(args))(args)
                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: (skipping 4 expansions in backtrace; use -fmacro-backtrace-limit=0 to see all)
/usr/include/bpf/bpf_tracing.h:540:54: note: expanded from macro 'PT_REGS_PARM1_SYSCALL'
#define PT_REGS_PARM1_SYSCALL(x) (__PT_REGS_CAST(x)->__PT_PARM1_SYSCALL_REG)
                                  ~~~~~~~~~~~~~~~~~  ^
/usr/include/bpf/bpf_tracing.h:97:32: note: expanded from macro '__PT_PARM1_SYSCALL_REG'
#define __PT_PARM1_SYSCALL_REG __PT_PARM1_REG
                               ^
/usr/include/bpf/bpf_tracing.h:87:24: note: expanded from macro '__PT_PARM1_REG'
#define __PT_PARM1_REG di
                       ^
5 errors generated.
make: *** [Makefile:15: hello-buffer-config.bpf.o] Error 1

After much of the struggle, I could not figured out the issue.

However, I realize similar macro BPF_KPROBE_SYSCALL is used in chatper7 and there code was building.
I see vmlinux.h is not present in chatper7 and make in that directory creates it at runtime.
Ula.. I found the root cause :-)