Re: Credentials test patch

["Ulrich Drepper" <drepper@gmail.com>]

In sys_faccessat you temporarily allocate a cred object which is
discarded in the end.  With a few more macro definitions you could
create a dup_cred variant which initialized an automatic variable of
type struct cred.  This way the kmalloc/kfree pair would fall away.

access is actually used frequently.  For instance, ld.so uses it on
every startup as a quicker possibility to check for a file which
usually doesn't exist.  So, speeding up access has some small effect
on performance.  The resulting code might actually reduce the kernel
size a bit due to all the checks and calls which go away.