Re: [PATCH v2 2/4] powerpc/interrupt: Refactor prep_irq_for_user_exit()

From: Nicholas Piggin
Date: Thu Jun 10 2021 - 22:31:51 EST


Excerpts from Christophe Leroy's message of June 5, 2021 12:56 am:
> prep_irq_for_user_exit() is a superset of
> prep_irq_for_kernel_enabled_exit().
>
> Refactor it.

I like the refactoring, but now prep_irq_for_user_exit() is calling
prep_irq_for_kernel_enabled_exit(), which seems like the wrong naming.

You could re-name prep_irq_for_kernel_enabled_exit() to
prep_irq_for_enabled_exit() maybe? Or it could be
__prep_irq_for_enabled_exit() then prep_irq_for_kernel_enabled_exit()
and prep_irq_for_user_exit() would both call it.

Otherwise

Reviewed-by: Nicholas Piggin <npiggin@xxxxxxxxx>

>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> ---
> arch/powerpc/kernel/interrupt.c | 25 +++++--------------------
> 1 file changed, 5 insertions(+), 20 deletions(-)
>
> diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
> index 539455c62c5b..b6aa80930733 100644
> --- a/arch/powerpc/kernel/interrupt.c
> +++ b/arch/powerpc/kernel/interrupt.c
> @@ -78,29 +78,14 @@ static notrace __always_inline bool prep_irq_for_kernel_enabled_exit(bool restar
> */
> static notrace __always_inline bool prep_irq_for_user_exit(void)
> {
> - user_enter_irqoff();
> - /* This must be done with RI=1 because tracing may touch vmaps */
> - trace_hardirqs_on();
> -
> -#ifdef CONFIG_PPC32
> - __hard_EE_RI_disable();
> -#else
> - if (exit_must_hard_disable())
> - __hard_EE_RI_disable();
> + bool ret;
>
> - /* This pattern matches prep_irq_for_idle */
> - if (unlikely(lazy_irq_pending_nocheck())) {
> - if (exit_must_hard_disable()) {
> - local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
> - __hard_RI_enable();
> - }
> - trace_hardirqs_off();
> + user_enter_irqoff();
> + ret = prep_irq_for_kernel_enabled_exit(true);
> + if (!ret)
> user_exit_irqoff();
>
> - return false;
> - }
> -#endif
> - return true;
> + return ret;
> }
>
> /* Has to run notrace because it is entered not completely "reconciled" */
> --
> 2.25.0
>
>