Hi.
Thanks for reviewing. I'll incorporate your suggestions, except this one, and resend.
On 03/13/2014 12:19 PM, David Herrmann wrote:
Hi
On Thu, Mar 13, 2014 at 11:57 AM, Thomas Hellstrom thellstrom@vmware.com wrote:
...
- if (cmd & IOC_IN) { - if (copy_from_user(kdata, (void __user *)arg, - usize) != 0) { - retcode = -EFAULT; + retcode = drm_ioctl_permit(ioctl->flags, file_priv); + if (unlikely(retcode))
That "unlikely" seems redundant given that all error paths in drm_ioctl_permit() already are "unlikely".
Yes, we know that's true, but I don't think compilers in general can combine branch prediction hints in that way, or even have the information necessary to do it. I mean even if each individual test resulting in an error is unlikely, how could the compiler know that all tests combined would result in an error being unlikely?
/Thomas