From 951bdfd077dbe3f9ff5a4274e42b46c964c1696e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 20 Oct 2020 15:37:04 +0100 Subject: [PATCH] FROMLIST: arm: Mark the recheduling IPI as raw interrupt Flag the rescheduling IPI as 'raw', making sure such interrupt skips both tick management and irqtime accounting. Bug: 191808738 Link: https://lore.kernel.org/lkml/20201124141449.572446-5-maz@kernel.org/ Change-Id: Ia9c2b989621eef6f49a1c30a08302a448ae286e6 Signed-off-by: Marc Zyngier [minor port to 5.10] Signed-off-by: Stephen Dickey --- arch/arm/Kconfig | 1 + arch/arm/kernel/smp.c | 4 ++++ 2 files changed, 5 insertions(+) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 002e0cf025f5..e485c4813441 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -51,6 +51,7 @@ config ARM select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI select GENERIC_CLOCKEVENTS_BROADCAST if SMP select GENERIC_IRQ_IPI if SMP + select ARCH_WANTS_IRQ_RAW if GENERIC_IRQ_IPI select GENERIC_CPU_AUTOPROBE select GENERIC_EARLY_IOREMAP select GENERIC_IDLE_POLL_SETUP diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index e3ae634a36d5..ba27e184402a 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -742,6 +742,10 @@ void __init set_smp_ipi_range(int ipi_base, int n) ipi_desc[i] = irq_to_desc(ipi_base + i); irq_set_status_flags(ipi_base + i, IRQ_HIDDEN); + + /* The recheduling IPI is special... */ + if (i == IPI_RESCHEDULE) + __irq_modify_status(ipi_base + i, 0, IRQ_RAW, ~0); } ipi_irq_base = ipi_base;