[PATCH RFC v2 0/4] syscalls: Add a shared table for all archs

[André Almeida]

While implementing a new syscall, we need to wire up it's number to the arch
table. Since syscall number 403, all architectures are on sync regarding the
number (except alpha), which make things a lot easier but more repetitive as
well. Have a look at commit b36d4b6aa88 ("arch: hookup listns() system call"),
with 15 lines of mostly:

  +470    common  listns                          sys_listns

There's already a "common" table shared with a bunch of archs at
`scripts/syscall.tbl`, but due to historical reasons some archs will never be
able to move to this table and share all the numbers.

The generic table starts from 403 (clock_gettime64), the first common syscall.
The scripts are adapted to x86 specifics, like not generating the compat entry
point for x86_64 and placing x86_x32 things in the proper order. x32 is likely
to be dropped from Linux soon but for the moment I left the support there. If
this sounds good, next revision I can add the docs bits too.

I've tested this with x86 and arm64, by comparing the syscalls_*.h and
unistd_*.h files generated before and after this patchset and they are
identical.

Thanks!
	André

Changes in v2:
- Managed to move to the real first common syscall: 403 (clock_gettime64)
- Added -no-compat option to be used with x86_64
- v1: https://patch.msgid.link/20260724-tonyk-syscall_table-v1-0-9c53188423da@xxxxxxxxxx

---
André Almeida (4):
      syscalls: Create unified partial table for all archs
      syscalls: Add support for x86_x32 for the common syscall table
      x86: Use common syscall table
      scripts/syscall.tbl: Use the common table

 arch/arm64/tools/syscall_32.tbl        | 68 ----------------------------
 arch/x86/entry/syscalls/Makefile       | 16 ++++---
 arch/x86/entry/syscalls/syscall_32.tbl | 68 ----------------------------
 arch/x86/entry/syscalls/syscall_64.tbl | 48 --------------------
 scripts/Makefile.asm-headers           |  4 +-
 scripts/syscall.tbl                    | 68 ----------------------------
 scripts/syscall_common.tbl             | 72 +++++++++++++++++++++++++++++
 scripts/syscallhdr.sh                  | 83 ++++++++++++++++++++++++++++------
 scripts/syscalltbl.sh                  | 35 +++++++++++---
 9 files changed, 181 insertions(+), 281 deletions(-)
---
base-commit: af5e34a41cd607c00ef752e00331736570992354
change-id: 20260724-tonyk-syscall_table-928bbb1b26bb

Best regards,
--  
André Almeida <andrealmeid@xxxxxxxxxx>