[PATCHv2 5/5] irqchip/GICv3: make reschedule-ipi light weight
From: Pingfan Liu <hidden>
Date: 2021-09-24 13:33:26
Also in:
lkml
Subsystem:
arm generic interrupt controller drivers, irqchip drivers, the rest · Maintainers:
Marc Zyngier, Thomas Gleixner, Linus Torvalds
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 <redacted> 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 <redacted> Cc: Thomas Gleixner <redacted> Cc: Yuichi Ito <redacted> 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; + 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)
--
2.31.1
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