[PATCH 0/3] readfile(2): a new syscall to make open/read/close faster

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

Here is a tiny new syscall, readfile, that makes it simpler to read
small/medium sized files all in one shot, no need to do open/read/close.
This is especially helpful for tools that poke around in procfs or
sysfs, making a little bit of a less system load than before, especially
as syscall overheads go up over time due to various CPU bugs being
addressed.

There are 4 patches in this series, the first 3 are against the kernel
tree, adding the syscall logic, wiring up the syscall, and adding some
tests for it.

The last patch is agains the man-pages project, adding a tiny man page
to try to describe the new syscall.

Greg Kroah-Hartman (3):
  readfile: implement readfile syscall
  arch: wire up the readfile syscall
  selftests: add readfile(2) selftests

 arch/alpha/kernel/syscalls/syscall.tbl        |   1 +
 arch/arm/tools/syscall.tbl                    |   1 +
 arch/arm64/include/asm/unistd.h               |   2 +-
 arch/arm64/include/asm/unistd32.h             |   2 +
 arch/ia64/kernel/syscalls/syscall.tbl         |   1 +
 arch/m68k/kernel/syscalls/syscall.tbl         |   1 +
 arch/microblaze/kernel/syscalls/syscall.tbl   |   1 +
 arch/mips/kernel/syscalls/syscall_n32.tbl     |   1 +
 arch/mips/kernel/syscalls/syscall_n64.tbl     |   1 +
 arch/mips/kernel/syscalls/syscall_o32.tbl     |   1 +
 arch/parisc/kernel/syscalls/syscall.tbl       |   1 +
 arch/powerpc/kernel/syscalls/syscall.tbl      |   1 +
 arch/s390/kernel/syscalls/syscall.tbl         |   1 +
 arch/sh/kernel/syscalls/syscall.tbl           |   1 +
 arch/sparc/kernel/syscalls/syscall.tbl        |   1 +
 arch/x86/entry/syscalls/syscall_32.tbl        |   1 +
 arch/x86/entry/syscalls/syscall_64.tbl        |   1 +
 arch/xtensa/kernel/syscalls/syscall.tbl       |   1 +
 fs/open.c                                     |  50 +++
 include/linux/syscalls.h                      |   2 +
 include/uapi/asm-generic/unistd.h             |   4 +-
 tools/testing/selftests/Makefile              |   1 +
 tools/testing/selftests/readfile/.gitignore   |   3 +
 tools/testing/selftests/readfile/Makefile     |   7 +
 tools/testing/selftests/readfile/readfile.c   | 285 +++++++++++++++++
 .../selftests/readfile/readfile_speed.c       | 301 ++++++++++++++++++
 26 files changed, 671 insertions(+), 2 deletions(-)
 create mode 100644 tools/testing/selftests/readfile/.gitignore
 create mode 100644 tools/testing/selftests/readfile/Makefile
 create mode 100644 tools/testing/selftests/readfile/readfile.c
 create mode 100644 tools/testing/selftests/readfile/readfile_speed.c

-- 
2.27.0