Message ID | 20220928204634.3036650-7-adhemerval.zanella@linaro.org |
---|---|
State | Superseded |
Headers | |
Series | Optimize posix_spawn signal setup with clone3 | |
Checks
Context | Check | Description |
---|---|---|
dj/TryBot-apply_patch | success | Patch applied to master at the time it was sent |
Commit Message
diff --git a/sysdeps/unix/sysv/linux/riscv/clone3.S b/sysdeps/unix/sysv/linux/riscv/clone3.S new file mode 100644 index 0000000000..1e6e807aa0 --- /dev/null +++ b/sysdeps/unix/sysv/linux/riscv/clone3.S @@ -0,0 +1,83 @@ +/* The clone3 syscall wrapper. Linux/RISC-V version. + Copyright (C) 2022 Free Software Foundation, Inc. + + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#include <asm/errno.h> +#include <sys/asm.h> +#include <sysdep.h> + +/* The userland implementation is: + int clone3 (struct clone_args *cl_args, size_t size, + int (*func)(void *arg), void *arg); + + the kernel entry is: + int clone3 (struct clone_args *cl_args, size_t size); + + The parameters are passed in registers from userland: + a0: cl_args + a1: size + a2: func + a3: arg */ + + .text +ENTRY(__clone3) + /* Sanity check args. */ + beqz a0, L(invalid) /* No NULL cl_args pointer. */ + beqz a2, L(invalid) /* No NULL function pointer. */ + + /* Do the system call, the kernel expects: + a7: system call number + a0: cl_args + a1: size */ + li a7, __NR_clone3 + scall + + bltz a0, L(error) + beqz a0, L(thread_start) + + ret + +L(invalid): + li a0, -EINVAL +L(error): + tail __syscall_error +END (__clone3) + +ENTRY(__thread_start_clone3) +L(thread_start): + /* Terminate call stack by noting ra is undefined. Use a dummy + .cfi_label to force starting the FDE. */ + .cfi_label .Ldummy + cfi_undefined (ra) + + /* Align stack to a 128-bit boundary as per RISC-V ABI. */ + andi sp, sp, ALMASK + + /* Restore the arg for user's function and call the user's + function. */ + mv a1, a2 /* Function pointer. */ + mv a0, a3 /* Argument pointer. */ + jalr a1 + + /* Call exit with the function's return value. */ + li a7, __NR_exit + scall +END(__thread_start_clone3) + +libc_hidden_def (__clone3) +weak_alias (__clone3, clone3) diff --git a/sysdeps/unix/sysv/linux/riscv/sysdep.h b/sysdeps/unix/sysv/linux/riscv/sysdep.h index 9b03b10567..57523dc7b7 100644 --- a/sysdeps/unix/sysv/linux/riscv/sysdep.h +++ b/sysdeps/unix/sysv/linux/riscv/sysdep.h @@ -150,6 +150,7 @@ /* RV32 does not support the gettime VDSO syscalls. */ # endif +# define HAVE_CLONE3_WRAPPER 1 /* List of system calls which are supported as vsyscalls (for RV32 and RV64). */