Messages in this thread | | | Date | Sun, 24 Aug 2014 13:05:39 -0700 | Subject | Re: [PATCH 2/5] x86, fpu: don't drop_fpu() in __restore_xstate_sig() if use_eager_fpu() | From | Linus Torvalds <> |
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I really dislike this one.
If I read it right, you now do *two* math_state_restore calls for each FPU signal state restore. That's potentially quite expensive.
Also, you can actually end up with multiple threads pointing to the same math state in init_task.thread.fpu.state, right? Why is that any better than just having the save state temporarily contain garbage?
The other patches look sane, this one I really don't like. You may have good reasons for it, but it's disgusting.
Linus
On Sun, Aug 24, 2014 at 12:47 PM, Oleg Nesterov <oleg@redhat.com> wrote: > __restore_xstate_sig() calls math_state_restore() with preemption > enabled, not good. But this is minor, [...]
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