Add some other common headers for basic LoongArch support.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

We were getting the file by luck, from one of the paths in -I, fix it to
get it from the proper place:

  $ cd tools/include/uapi/asm/
  [acme@quaco asm]$ grep include bitsperlong.h
  #include "../../arch/x86/include/uapi/asm/bitsperlong.h"
  #include "../../arch/arm64/include/uapi/asm/bitsperlong.h"
  #include "../../arch/powerpc/include/uapi/asm/bitsperlong.h"
  #include "../../arch/s390/include/uapi/asm/bitsperlong.h"
  #include "../../arch/sparc/include/uapi/asm/bitsperlong.h"
  #include "../../arch/mips/include/uapi/asm/bitsperlong.h"
  #include "../../arch/ia64/include/uapi/asm/bitsperlong.h"
  #include "../../arch/riscv/include/uapi/asm/bitsperlong.h"
  #include "../../arch/alpha/include/uapi/asm/bitsperlong.h"
  #include <asm-generic/bitsperlong.h>
  $ ls -la ../../arch/x86/include/uapi/asm/bitsperlong.h
  ls: cannot access '../../arch/x86/include/uapi/asm/bitsperlong.h': No such file or directory
  $ ls -la ../../../arch/*/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 237 ../../../arch/alpha/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 841 ../../../arch/arm64/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 966 ../../../arch/hexagon/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 234 ../../../arch/ia64/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 100 ../../../arch/microblaze/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 244 ../../../arch/mips/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 352 ../../../arch/parisc/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 312 ../../../arch/powerpc/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 353 ../../../arch/riscv/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 292 ../../../arch/s390/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 323 ../../../arch/sparc/include/uapi/asm/bitsperlong.h
  -rw-rw-r--. 1 320 ../../../arch/x86/include/uapi/asm/bitsperlong.h
  $

Found while fixing some other problem, before it was escaping the
tools/ chroot and using stuff in the kernel sources:

    CC       /tmp/build/perf/util/find_bit.o
In file included from /git/linux/tools/include/../../arch/x86/include/uapi/asm/bitsperlong.h:11,
                 from /git/linux/tools/include/uapi/asm/bitsperlong.h:3,
                 from /git/linux/tools/include/linux/bits.h:6,
                 from /git/linux/tools/include/linux/bitops.h:13,
                 from ../lib/find_bit.c:17:

  # cd /git/linux/tools/include/../../arch/x86/include/uapi/asm/
  # pwd
  /git/linux/arch/x86/include/uapi/asm
  #

Now it is getting the one we want it to, i.e. the one inside tools/:

    CC       /tmp/build/perf/util/find_bit.o
  In file included from /git/linux/tools/arch/x86/include/uapi/asm/bitsperlong.h:11,
                   from /git/linux/tools/include/linux/bits.h:6,
                   from /git/linux/tools/include/linux/bitops.h:13,

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-8f8cfqywmf6jk8a3ucr0ixhu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Bob Tracy <rct@frus.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>

The BPF library is not built on 64-bit RISC-V, as the BPF feature is
not detected. Looking more in details, feature/test-bpf.c fails to build
with the following error:

| In file included from /tmp/linux-4.19.12/tools/include/uapi/asm/bitsperlong.h:17,
|                  from /tmp/linux-4.19.12/tools/include/uapi/asm-generic/unistd.h:2,
|                  from /usr/include/riscv64-linux-gnu/asm/unistd.h:1,
|                  from test-bpf.c:2:
| /tmp/linux-4.19.12/tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h
|  #error Inconsistent word size. Check asm/bitsperlong.h
|   ^~~~~

The UAPI from the tools directory is missing RISC-V support, therefore
bitsperlong.h from asm-generic is used, defaulting to 32 bits.

Fix that by adding tools/arch/riscv/include/uapi/asm/bitsperlong.h as
a copy of arch/riscv/include/uapi/asm/bitsperlong.h and by updating
tools/include/uapi/asm/bitsperlong.h.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

The BPF selftests fail to build with missing headers
'asm/bitsperlong.h' and 'asm/errno.h'.

These already exist in 'tools/arch/[arch]/include';
add architecture-agnostic header files in 'tools/include/uapi'
to reference them.

Signed-off-by: Sirio Balmelli <sirio@b-ad.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>