[PATCH 0/2] arm64: make it possible to enable threadirqs

[PATCH 0/2] arm64: make it possible to enable threadirqs

[Anders Roxell]

Hi,

This patchset makes it possible to pass "threadirqs" on the CONFIG_CMDLINE to
make IRQs threaded.
This is safe to use now because all timer interrupts and the perf interrupt are
marked NO_THREAD.

NOTE: I had to add this patch [1] to be able to test this on a juno board.
Without this patch, I see unhandled IRQs in mainline. However, it is unclear
whether or not this will be the actual fix that appears in mainline [2].

Cheers,
Anders

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-January/319901.html
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/322251.html

Anders Roxell (2):
  arm64: Mark PMU interrupt IRQF_NO_THREAD
  arm64: Allow forced irq threading

 arch/arm64/Kconfig             | 1 +
 arch/arm64/kernel/perf_event.c | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

-- 
2.1.4

[PATCH 1/2] arm64: Mark PMU interrupt IRQF_NO_THREAD

[Anders Roxell]

Mark the PMU interrupts as non-threadable, as is the case with
arch/arm: d9c3365 ARM: 7813/1: Mark pmu interupt IRQF_NO_THREAD

Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
---
 arch/arm64/kernel/perf_event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 195991d..7db5c84 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -488,7 +488,7 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu)
 			}
 
 			err = request_irq(irq, armpmu->handle_irq,
-					IRQF_NOBALANCING,
+					IRQF_NOBALANCING | IRQF_NO_THREAD,
 					"arm-pmu", armpmu);
 			if (err) {
 				pr_err("unable to request IRQ%d for ARM PMU counters\n",
-- 
2.1.4

[PATCH 1/2] arm64: Mark PMU interrupt IRQF_NO_THREAD

[Will Deacon]

On Tue, Apr 21, 2015 at 04:05:54PM +0100, Anders Roxell wrote:
> Mark the PMU interrupts as non-threadable, as is the case with
> arch/arm: d9c3365 ARM: 7813/1: Mark pmu interupt IRQF_NO_THREAD
> 
> Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
> ---
>  arch/arm64/kernel/perf_event.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Acked-by: Will Deacon <will.deacon@arm.com>

Catalin can queue this for 4.2.

Cheers,

Will

> diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
> index 195991d..7db5c84 100644
> --- a/arch/arm64/kernel/perf_event.c
> +++ b/arch/arm64/kernel/perf_event.c
> @@ -488,7 +488,7 @@ armpmu_reserve_hardware(struct arm_pmu *armpmu)
>  			}
>  
>  			err = request_irq(irq, armpmu->handle_irq,
> -					IRQF_NOBALANCING,
> +					IRQF_NOBALANCING | IRQF_NO_THREAD,
>  					"arm-pmu", armpmu);
>  			if (err) {
>  				pr_err("unable to request IRQ%d for ARM PMU counters\n",
> -- 
> 2.1.4
> 

[PATCH 2/2] arm64: Allow forced irq threading

[Anders Roxell]

Now its safe to allow forced interrupt threading for arm64,
all timer interrupts and the perf interrupt are marked NO_THREAD, as is
the case with arch/arm: da0ec6f ARM: 7814/2: Allow forced irq threading

Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
---
 arch/arm64/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b8d96f1..1abb840 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -68,6 +68,7 @@ config ARM64
 	select HAVE_RCU_TABLE_FREE
 	select HAVE_SYSCALL_TRACEPOINTS
 	select IRQ_DOMAIN
+	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
 	select NO_BOOTMEM
 	select OF
-- 
2.1.4