From 54d5d42404e7705cf3804593189e963350d470e5 Mon Sep 17 00:00:00 2001 From: Ashok Raj Date: Tue, 6 Sep 2005 15:16:15 -0700 Subject: [PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity When handling writes to /proc/irq, current code is re-programming rte entries directly. This is not recommended and could potentially cause chipset's to lockup, or cause missing interrupts. CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the interrupt is pending. The same needs to be done for /proc/irq handling as well. Otherwise user space irq balancers are really not doing the right thing. - Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for lack of a generic name. - added move_irq out of IRQ_BALANCE, and added this same to X86_64 - Added new proc handler for write, so we can do deferred write at irq handling time. - Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead it now shows only active cpu masks, or exactly what was set. - Provided a common move_irq implementation, instead of duplicating when using generic irq framework. Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off. Tested UP builds as well. MSI testing: tbd: I have cards, need to look for a x-over cable, although I did test an earlier version of this patch. Will test in a couple days. Signed-off-by: Ashok Raj Acked-by: Zwane Mwaikambo Grudgingly-acked-by: Andi Kleen Signed-off-by: Coywolf Qi Hunt Signed-off-by: Ashok Raj Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/pci/msi.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 2b85aa39f95..532f73bb222 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -91,6 +91,7 @@ static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask) { struct msi_desc *entry; struct msg_address address; + unsigned int irq = vector; entry = (struct msi_desc *)msi_desc[vector]; if (!entry || !entry->dev) @@ -112,6 +113,7 @@ static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask) entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask); pci_write_config_dword(entry->dev, msi_lower_address_reg(pos), address.lo_address.value); + set_native_irq_info(irq, cpu_mask); break; } case PCI_CAP_ID_MSIX: @@ -125,22 +127,13 @@ static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask) MSI_TARGET_CPU_SHIFT); entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask); writel(address.lo_address.value, entry->mask_base + offset); + set_native_irq_info(irq, cpu_mask); break; } default: break; } } - -#ifdef CONFIG_IRQBALANCE -static inline void move_msi(int vector) -{ - if (!cpus_empty(pending_irq_balance_cpumask[vector])) { - set_msi_affinity(vector, pending_irq_balance_cpumask[vector]); - cpus_clear(pending_irq_balance_cpumask[vector]); - } -} -#endif /* CONFIG_IRQBALANCE */ #endif /* CONFIG_SMP */ static void mask_MSI_irq(unsigned int vector) @@ -191,13 +184,13 @@ static void shutdown_msi_irq(unsigned int vector) static void end_msi_irq_wo_maskbit(unsigned int vector) { - move_msi(vector); + move_native_irq(vector); ack_APIC_irq(); } static void end_msi_irq_w_maskbit(unsigned int vector) { - move_msi(vector); + move_native_irq(vector); unmask_MSI_irq(vector); ack_APIC_irq(); } -- cgit v1.2.3