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
