From fef05a078b6fa1e9047e0486f1f6daf70664fd12 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Tue, 23 Apr 2024 10:41:11 -0700 Subject: x86/irq: Factor out common code for checking pending interrupts Use a common function for checking pending interrupt vector in APIC IRR instead of duplicated open coding them. Additional checks for posted MSI vectors can then be contained in this function. Signed-off-by: Jacob Pan Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240423174114.526704-10-jacob.jun.pan@linux.intel.com --- arch/x86/include/asm/apic.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'arch/x86/include/asm/apic.h') diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index e6ab0cf15ed5..50f9781fa3ed 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -500,6 +500,17 @@ static inline bool lapic_vector_set_in_irr(unsigned int vector) return !!(irr & (1U << (vector % 32))); } +static inline bool is_vector_pending(unsigned int vector) +{ + unsigned int irr; + + irr = apic_read(APIC_IRR + (vector / 32 * 0x10)); + if (irr & (1 << (vector % 32))) + return true; + + return false; +} + /* * Warm reset vector position: */ -- cgit From ce0a92871179f8ca58ae8e3cf50e726a163bf831 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Tue, 23 Apr 2024 10:41:12 -0700 Subject: x86/irq: Extend checks for pending vectors to posted interrupts During interrupt affinity change, it is possible to have interrupts delivered to the old CPU after the affinity has changed to the new one. To prevent lost interrupts, local APIC IRR is checked on the old CPU. Similar checks must be done for posted MSIs given the same reason. Consider the following scenario: Device system agent iommu memory CPU/LAPIC 1 FEEX_XXXX 2 Interrupt request 3 Fetch IRTE -> 4 ->Atomic Swap PID.PIR(vec) Push to Global Observable(GO) 5 if (ON*) done;* else 6 send a notification -> * ON: outstanding notification, 1 will suppress new notifications If the affinity change happens between 3 and 5 in the IOMMU, the old CPU's posted interrupt request (PIR) could have the pending bit set for the vector being moved. Add a helper function to check individual vector status. Then use the helper to check for pending interrupts on the source CPU's PID. Signed-off-by: Jacob Pan Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20240423174114.526704-11-jacob.jun.pan@linux.intel.com --- arch/x86/include/asm/apic.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/x86/include/asm/apic.h') diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 50f9781fa3ed..5644c396713e 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -14,6 +14,7 @@ #include #include #include +#include #define ARCH_APICTIMER_STOPS_ON_C3 1 @@ -508,7 +509,7 @@ static inline bool is_vector_pending(unsigned int vector) if (irr & (1 << (vector % 32))) return true; - return false; + return pi_pending_this_cpu(vector); } /* -- cgit From 6ecc2e7932fe8f132d3b671685f9995785f19e9a Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Mon, 6 May 2024 10:56:12 -0700 Subject: x86/irq: Use existing helper for pending vector check lapic_vector_set_in_irr() is already available, use it for checking pending vectors at the local APIC. No functional change. Signed-off-by: Jacob Pan Signed-off-by: Thomas Gleixner Reviewed-by: Imran Khan Link: https://lore.kernel.org/r/20240506175612.1141095-1-jacob.jun.pan@linux.intel.com --- arch/x86/include/asm/apic.h | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) (limited to 'arch/x86/include/asm/apic.h') diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 5644c396713e..467532b3e070 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -503,13 +503,7 @@ static inline bool lapic_vector_set_in_irr(unsigned int vector) static inline bool is_vector_pending(unsigned int vector) { - unsigned int irr; - - irr = apic_read(APIC_IRR + (vector / 32 * 0x10)); - if (irr & (1 << (vector % 32))) - return true; - - return pi_pending_this_cpu(vector); + return lapic_vector_set_in_irr(vector) || pi_pending_this_cpu(vector); } /* -- cgit