In article <20030313061926.S3910@devserv.devel.redhat.com>,
Jakub Jelinek <jakub@redhat.com> wrote:
>
>Anyone remembers why get_current function (on arches which define
>current to get_current()) is not const
Because it makes no difference at all on x86, since gcc will ignore
"const" for inline functions. At least that used to be true.
> and why on x86-64
>the movq %%gs:0, %0 inline asm is volatile with "memory" clobber?
Can't help you on that one, but it looks like it uses various helper
functions for doing the x86-64 per-processor data structures, and I bet
those helper functions are shared by _other_ users who definitely want
to have their data properly re-read. Ie "current()" may be constant in
process context, but that sure isn't true about a lot of other things in
the per-processor data structures.
Linus
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This archive was generated by hypermail 2b29 : Sun Mar 23 2003 - 22:00:19 EST