Messages in this thread | | | Date | Fri, 22 Oct 2021 09:52:02 +0100 | From | Mark Rutland <> | Subject | Re: [PATCH 05/15] irq: add generic_handle_arch_irq() |
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On Fri, Oct 22, 2021 at 10:33:53AM +0800, Guo Ren wrote: > On Fri, Oct 22, 2021 at 2:03 AM Mark Rutland <mark.rutland@arm.com> wrote: > > > > Several architectures select GENERIC_IRQ_MULTI_HANDLER and branch to > > handle_arch_irq() without performing any entry accounting. > > > > Add a generic wrapper to handle the commoon irqentry work when invoking
Ah, I'd typo'd 'common' there; I'll go fix that...
> > handle_arch_irq(). Where an architecture needs to perform some entry > > accounting itself, it will need to invoke handle_arch_irq() itself. > > > > In subsequent patches it will become the responsibilty of the entry code > > to set the irq regs when entering an IRQ (rather than deferring this to > > an irqchip handler), so generic_handle_arch_irq() is made to set the irq > > regs now. This can be redundant in some cases, but is never harmful as > > saving/restoring the old regs nests safely. > Shall we remove old_regs save/restore in handle_domain_irq? It's duplicated.
We do, in patch 15 when handle_domain_irq() is removed entirely. :)
Removing it immediately in this patch would require more ifdeffery and/or another copy of handle_domain_irq(), and since the duplication doesn't cause a functional problem, I think it's better to live with the temporary duplication for the next few patches than to try to optimize the intermediate steps at the cost of legibility.
Thanks, Mark.
> > Signed-off-by: Mark Rutland <mark.rutland@arm.com> > > Cc: Marc Zyngier <maz@kernel.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > --- > > kernel/irq/handle.c | 18 ++++++++++++++++++ > > 1 file changed, 18 insertions(+) > > > > diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c > > index 221d80c31e94..27182003b879 100644 > > --- a/kernel/irq/handle.c > > +++ b/kernel/irq/handle.c > > @@ -14,6 +14,8 @@ > > #include <linux/interrupt.h> > > #include <linux/kernel_stat.h> > > > > +#include <asm/irq_regs.h> > > + > > #include <trace/events/irq.h> > > > > #include "internals.h" > > @@ -226,4 +228,20 @@ int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) > > handle_arch_irq = handle_irq; > > return 0; > > } > > + > > +/** > > + * generic_handle_arch_irq - root irq handler for architectures which do no > > + * entry accounting themselves > > + * @regs: Register file coming from the low-level handling code > > + */ > > +asmlinkage void noinstr generic_handle_arch_irq(struct pt_regs *regs) > > +{ > > + struct pt_regs *old_regs; > > + > > + irq_enter(); > > + old_regs = set_irq_regs(regs); > > + handle_arch_irq(regs); > > + set_irq_regs(old_regs); > > + irq_exit(); > > +} > > #endif > > -- > > 2.11.0 > > > > > -- > Best Regards > Guo Ren > > ML: https://lore.kernel.org/linux-csky/
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