Hello,
Is it really worth making the code a bit obscure? The mapping RPC will
be way more expensive than branch misprediction...
Samuel
Sergey Bugaev, le lun. 24 avril 2023 00:55:25 +0300, a ecrit:
> Signed-off-by: Sergey Bugaev <buga...@gmail.com>
> ---
> sysdeps/mach/hurd/mmap.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/sysdeps/mach/hurd/mmap.c b/sysdeps/mach/hurd/mmap.c
> index 790eb238..d570be24 100644
> --- a/sysdeps/mach/hurd/mmap.c
> +++ b/sysdeps/mach/hurd/mmap.c
> @@ -42,7 +42,8 @@ __mmap (void *addr, size_t len, int prot, int flags, int
> fd, off_t offset)
> mapaddr = (vm_address_t) addr;
>
> /* ADDR and OFFSET must be page-aligned. */
> - if ((mapaddr & (__vm_page_size - 1)) || (offset & (__vm_page_size - 1)))
> + if (__glibc_unlikely ((mapaddr & (__vm_page_size - 1))
> + || (offset & (__vm_page_size - 1))))
> return (void *) (long int) __hurd_fail (EINVAL);
>
> vmprot = VM_PROT_NONE;
> @@ -73,7 +74,8 @@ __mmap (void *addr, size_t len, int prot, int flags, int
> fd, off_t offset)
> mach_port_t robj, wobj;
> if (err = HURD_DPORT_USE (fd, __io_map (port, &robj, &wobj)))
> {
> - if (err == MIG_BAD_ID || err == EOPNOTSUPP || err == ENOSYS)
> + if (__glibc_unlikely (err == MIG_BAD_ID || err == EOPNOTSUPP
> + || err == ENOSYS))
> err = ENODEV; /* File descriptor doesn't support mmap. */
> return (void *) (long int) __hurd_dfail (fd, err);
> }
> @@ -173,7 +175,7 @@ __mmap (void *addr, size_t len, int prot, int flags, int
> fd, off_t offset)
> if (err == KERN_PROTECTION_FAILURE)
> err = EACCES;
>
> - if (err)
> + if (__glibc_unlikely (err))
> return (void *) (long int) __hurd_fail (err);
>
> return (void *) mapaddr;
> --
> 2.40.0
