Re: [RFC PATCH v2 09/11] powerpc: Add support to mask perf interrupts
From: Nicholas Piggin <npiggin@gmail.com>
Date: 2016-08-01 05:29:48
On Mon, 1 Aug 2016 00:36:27 +0530 Madhavan Srinivasan [off-list ref] wrote:
quoted hunk ↗ jump to hunk
/* * flags for paca->soft_enabled */ #define IRQ_DISABLE_LEVEL_NONE 0 #define IRQ_DISABLE_LEVEL_LINUX 1 +#define IRQ_DISABLE_LEVEL_PMU 2 + +#define MASK_IRQ_LEVEL IRQ_DISABLE_LEVEL_LINUX | IRQ_DISABLE_LEVEL_PMU #endif /* CONFIG_PPC64 */diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 2c87e82ecbe4..56dc71b82824 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S@@ -256,11 +256,11 @@ hardware_interrupt_pSeries: hardware_interrupt_hv: BEGIN_FTR_SECTION _MASKABLE_EXCEPTION_PSERIES(0x502, hardware_interrupt, - EXC_HV, SOFTEN_TEST_HV, IRQ_DISABLE_LEVEL_LINUX) + EXC_HV, SOFTEN_TEST_HV, MASK_IRQ_LEVEL)
So what I was expecting is that each exception handler would specify the level (or bit, if we use bitmask) at which it gets disabled. The test code will then test the exception level with the enable level (or s/level/mask). The way you have now is each exception handler specifying the bits which cause it to be disabled, but I think that's kind of backwards -- the disabler knows which interrupts it wants to disable, the exception handler does not know what disablers want to disable it :) So to disable PMU and "linux" interrupts for local_t operations, you would have: local_irq_set_mask(IRQ_DISABLE_LEVEL_LINUX|IRQ_DISABLE_LEVEL_PMU) And that would disable both handlers that test with IRQ_DISABLE_LEVEL_LINUX and IRQ_DISABLE_LEVEL_PMU Does that make sense? What do you think? Thanks, Nick