[PATCH resend 02/15] arm64: add abstractions for FPSIMD state manipulation

Catalin Marinas catalin.marinas at arm.com
Tue May 6 08:12:55 PDT 2014


On Tue, May 06, 2014 at 03:48:08PM +0100, Ard Biesheuvel wrote:
> On 6 May 2014 16:43, Catalin Marinas <catalin.marinas at arm.com> wrote:
> > On Thu, May 01, 2014 at 04:49:34PM +0100, Ard Biesheuvel wrote:
> >> diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
> >> index 4aef42a04bdc..86ac6a9bc86a 100644
> >> --- a/arch/arm64/kernel/fpsimd.c
> >> +++ b/arch/arm64/kernel/fpsimd.c
> >> @@ -87,6 +87,39 @@ void fpsimd_flush_thread(void)
> >>       preempt_enable();
> >>  }
> >>
> >> +/*
> >> + * Save the userland FPSIMD state of 'current' to memory
> >> + */
> >> +void fpsimd_preserve_current_state(void)
> >> +{
> >> +     fpsimd_save_state(&current->thread.fpsimd_state);
> >> +}
> >> +
> >> +/*
> >> + * Load the userland FPSIMD state of 'current' from memory
> >> + */
> >> +void fpsimd_restore_current_state(void)
> >> +{
> >> +     fpsimd_load_state(&current->thread.fpsimd_state);
> >> +}
> >> +
> >> +/*
> >> + * Load an updated userland FPSIMD state for 'current' from memory
> >> + */
> >> +void fpsimd_update_current_state(struct fpsimd_state *state)
> >> +{
> >> +     preempt_disable();
> >> +     fpsimd_load_state(state);
> >> +     preempt_enable();
> >> +}
> >
> > Minor - please update the comment above the functions to state that
> > preemption needs to be disabled by the caller.
> >
> 
> Do you mean in all three cases? And, by implication, that the
> preempt_disable()/enable() pair should be moved to the call site for
> fpsimd_update_current_state() ?

No, just the comment for the first two functions updated.

-- 
Catalin



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