| Message ID | 20210924132837.45994-6-kernelfans@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64/irqentry: remove duplicate housekeeping of | expand |
On Fri, 24 Sep 2021 14:28:37 +0100, Pingfan Liu <kernelfans@gmail.com> wrote: > > To achieve the light weight as > DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_reschedule_ipi) on x86, it had > better treat irqnr differently at the frontend. And let IPI_RESCHEDULE > call __irq_enter_raw() instead of irq_enter_rcu(). > > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Marc Zyngier <maz@kernel.org> > Cc: Joey Gouly <joey.gouly@arm.com> > Cc: Sami Tolvanen <samitolvanen@google.com> > Cc: Julien Thierry <julien.thierry@arm.com> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Yuichi Ito <ito-yuichi@fujitsu.com> > Cc: linux-kernel@vger.kernel.org > To: linux-arm-kernel@lists.infradead.org > --- > drivers/irqchip/irq-gic-v3.c | 15 +++++++++++++-- > 1 file changed, 13 insertions(+), 2 deletions(-) > > diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c > index 906538fa8771..593d4539a209 100644 > --- a/drivers/irqchip/irq-gic-v3.c > +++ b/drivers/irqchip/irq-gic-v3.c > @@ -709,6 +709,9 @@ static void gic_handle_nmi(struct pt_regs *regs) > gic_deactivate_unhandled(irqnr); > } > > +/* RESCHEDULE IPI hwirq nr is 0, and the only raw one */ > +static unsigned long raw_interrupt_mask = 1; I'm afraid you have the wrong end of the stick. This isn't a GIC property. This is an architecture decision, and only the architecture can expose what they want. M.
On Wed, Sep 29, 2021 at 08:24:34AM +0100, Marc Zyngier wrote: > On Fri, 24 Sep 2021 14:28:37 +0100, > Pingfan Liu <kernelfans@gmail.com> wrote: > > > > To achieve the light weight as > > DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_reschedule_ipi) on x86, it had > > better treat irqnr differently at the frontend. And let IPI_RESCHEDULE > > call __irq_enter_raw() instead of irq_enter_rcu(). > > > > Signed-off-by: Pingfan Liu <kernelfans@gmail.com> > > Cc: Catalin Marinas <catalin.marinas@arm.com> > > Cc: Will Deacon <will@kernel.org> > > Cc: Mark Rutland <mark.rutland@arm.com> > > Cc: Marc Zyngier <maz@kernel.org> > > Cc: Joey Gouly <joey.gouly@arm.com> > > Cc: Sami Tolvanen <samitolvanen@google.com> > > Cc: Julien Thierry <julien.thierry@arm.com> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > Cc: Yuichi Ito <ito-yuichi@fujitsu.com> > > Cc: linux-kernel@vger.kernel.org > > To: linux-arm-kernel@lists.infradead.org > > --- > > drivers/irqchip/irq-gic-v3.c | 15 +++++++++++++-- > > 1 file changed, 13 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c > > index 906538fa8771..593d4539a209 100644 > > --- a/drivers/irqchip/irq-gic-v3.c > > +++ b/drivers/irqchip/irq-gic-v3.c > > @@ -709,6 +709,9 @@ static void gic_handle_nmi(struct pt_regs *regs) > > gic_deactivate_unhandled(irqnr); > > } > > > > +/* RESCHEDULE IPI hwirq nr is 0, and the only raw one */ > > +static unsigned long raw_interrupt_mask = 1; > > I'm afraid you have the wrong end of the stick. This isn't a GIC > property. This is an architecture decision, and only the architecture > can expose what they want. > Could it done be export an interface int (*get_irq_nr)(pte_regs) to do_interrupt_handler()? So it can be seen as an architecture decision. Thanks, Pingfan > > -- > Without deviation from the norm, progress is not possible. > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 906538fa8771..593d4539a209 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -709,6 +709,9 @@ static void gic_handle_nmi(struct pt_regs *regs) gic_deactivate_unhandled(irqnr); } +/* RESCHEDULE IPI hwirq nr is 0, and the only raw one */ +static unsigned long raw_interrupt_mask = 1; + static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs) { u32 irqnr; @@ -729,12 +732,20 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs else isb(); - irq_enter_rcu(); + if (raw_interrupt_mask & 1 << irqnr) + __irq_enter_raw(); + else + irq_enter_rcu(); + if (handle_domain_irq(gic_data.domain, irqnr, regs)) { WARN_ONCE(true, "Unexpected interrupt received!\n"); gic_deactivate_unhandled(irqnr); } - irq_exit_rcu(); + + if (raw_interrupt_mask & 1 << irqnr) + __irq_exit_raw(); + else + irq_exit_rcu(); } static u32 gic_get_pribits(void)
To achieve the light weight as DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_reschedule_ipi) on x86, it had better treat irqnr differently at the frontend. And let IPI_RESCHEDULE call __irq_enter_raw() instead of irq_enter_rcu(). Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Joey Gouly <joey.gouly@arm.com> Cc: Sami Tolvanen <samitolvanen@google.com> Cc: Julien Thierry <julien.thierry@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yuichi Ito <ito-yuichi@fujitsu.com> Cc: linux-kernel@vger.kernel.org To: linux-arm-kernel@lists.infradead.org --- drivers/irqchip/irq-gic-v3.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)