Message ID | 20230112135853.3786675-6-adhemerval.zanella@linaro.org |
---|---|
State | New |
Headers | show |
Series | Optimize posix_spawn signal setup with clone3 | expand |
On 1/12/23 08:58, Adhemerval Zanella wrote: > It follow the internal signature: > > extern int clone3 (struct clone_args *__cl_args, size_t __size, > int (*__func) (void *__arg), void *__arg); > > Checked on aarch64-linux-gnu. OK for 2.28. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > --- > sysdeps/unix/sysv/linux/aarch64/clone3.S | 85 ++++++++++++++++++++++++ > sysdeps/unix/sysv/linux/aarch64/sysdep.h | 2 + > 2 files changed, 87 insertions(+) > create mode 100644 sysdeps/unix/sysv/linux/aarch64/clone3.S > > diff --git a/sysdeps/unix/sysv/linux/aarch64/clone3.S b/sysdeps/unix/sysv/linux/aarch64/clone3.S > new file mode 100644 > index 0000000000..88a1fa1e89 > --- /dev/null > +++ b/sysdeps/unix/sysv/linux/aarch64/clone3.S > @@ -0,0 +1,85 @@ > +/* The clone3 syscall wrapper. Linux/aarch64 version. > + Copyright (C) 2023 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 <sysdep.h> > +#define _ERRNO_H 1 > +#include <bits/errno.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: > + x0: cl_args > + x1: size > + x2: func > + x3: arg */ > + > + .text > +ENTRY(__clone3) > + PTR_ARG (0) > + PTR_ARG (1) > + PTR_ARG (3) > + PTR_ARG (4) > + /* Save args for the child. */ > + mov x10, x0 /* cl_args */ > + mov x11, x2 /* func */ > + mov x12, x3 /* args */ > + > + /* Sanity check args. */ > + mov x0, #-EINVAL > + cbz x10, .Lsyscall_error /* No NULL cl_args pointer. */ > + cbz x2, .Lsyscall_error /* No NULL function pointer. */ > + > + /* Do the system call, the kernel expects: > + x8: system call number > + x0: cl_args > + x1: size */ > + mov x0, x10 > + mov x8, #SYS_ify(clone3) > + svc 0x0 > + > + cmp x0, #0 > + beq thread_start > + blt .Lsyscall_error > + RET > +PSEUDO_END (__clone3) > + > + .align 4 > + .type thread_start, %function > +thread_start: > + cfi_startproc > + cfi_undefined (x30) > + mov x29, 0 > + > + /* Pick the function arg and execute. */ > + mov x0, x12 > + blr x11 > + > + /* We are done, pass the return value through x0. */ > + mov x8, #SYS_ify(exit) > + svc 0x0 > + cfi_endproc > + .size thread_start, .-thread_start OK. > + > +libc_hidden_def (__clone3) > +weak_alias (__clone3, clone3) > diff --git a/sysdeps/unix/sysv/linux/aarch64/sysdep.h b/sysdeps/unix/sysv/linux/aarch64/sysdep.h > index 6520fa15da..e94d1703ad 100644 > --- a/sysdeps/unix/sysv/linux/aarch64/sysdep.h > +++ b/sysdeps/unix/sysv/linux/aarch64/sysdep.h > @@ -165,6 +165,8 @@ > # define HAVE_CLOCK_GETTIME64_VSYSCALL "__kernel_clock_gettime" > # define HAVE_GETTIMEOFDAY_VSYSCALL "__kernel_gettimeofday" > > +# define HAVE_CLONE3_WRAPPER 1 OK. Enables the optimizations where possible. > + > # undef INTERNAL_SYSCALL_RAW > # define INTERNAL_SYSCALL_RAW(name, nr, args...) \ > ({ long _sys_result; \
diff --git a/sysdeps/unix/sysv/linux/aarch64/clone3.S b/sysdeps/unix/sysv/linux/aarch64/clone3.S new file mode 100644 index 0000000000..88a1fa1e89 --- /dev/null +++ b/sysdeps/unix/sysv/linux/aarch64/clone3.S @@ -0,0 +1,85 @@ +/* The clone3 syscall wrapper. Linux/aarch64 version. + Copyright (C) 2023 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 <sysdep.h> +#define _ERRNO_H 1 +#include <bits/errno.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: + x0: cl_args + x1: size + x2: func + x3: arg */ + + .text +ENTRY(__clone3) + PTR_ARG (0) + PTR_ARG (1) + PTR_ARG (3) + PTR_ARG (4) + /* Save args for the child. */ + mov x10, x0 /* cl_args */ + mov x11, x2 /* func */ + mov x12, x3 /* args */ + + /* Sanity check args. */ + mov x0, #-EINVAL + cbz x10, .Lsyscall_error /* No NULL cl_args pointer. */ + cbz x2, .Lsyscall_error /* No NULL function pointer. */ + + /* Do the system call, the kernel expects: + x8: system call number + x0: cl_args + x1: size */ + mov x0, x10 + mov x8, #SYS_ify(clone3) + svc 0x0 + + cmp x0, #0 + beq thread_start + blt .Lsyscall_error + RET +PSEUDO_END (__clone3) + + .align 4 + .type thread_start, %function +thread_start: + cfi_startproc + cfi_undefined (x30) + mov x29, 0 + + /* Pick the function arg and execute. */ + mov x0, x12 + blr x11 + + /* We are done, pass the return value through x0. */ + mov x8, #SYS_ify(exit) + svc 0x0 + cfi_endproc + .size thread_start, .-thread_start + +libc_hidden_def (__clone3) +weak_alias (__clone3, clone3) diff --git a/sysdeps/unix/sysv/linux/aarch64/sysdep.h b/sysdeps/unix/sysv/linux/aarch64/sysdep.h index 6520fa15da..e94d1703ad 100644 --- a/sysdeps/unix/sysv/linux/aarch64/sysdep.h +++ b/sysdeps/unix/sysv/linux/aarch64/sysdep.h @@ -165,6 +165,8 @@ # define HAVE_CLOCK_GETTIME64_VSYSCALL "__kernel_clock_gettime" # define HAVE_GETTIMEOFDAY_VSYSCALL "__kernel_gettimeofday" +# define HAVE_CLONE3_WRAPPER 1 + # undef INTERNAL_SYSCALL_RAW # define INTERNAL_SYSCALL_RAW(name, nr, args...) \ ({ long _sys_result; \