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| author | Oren Twaig <oren@scalemp.com> | 2014-04-28 10:21:37 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-04-28 09:27:34 +0200 |
| commit | 39025ba38278f3003ee538409f7c98970620ef49 (patch) | |
| tree | f3ed243da52148e4fb188e2805ad048e32a34727 /arch/x86 | |
| parent | 8f2dd677bec68fb55904799a82674c9e64b23be3 (diff) | |
| download | linux-39025ba38278f3003ee538409f7c98970620ef49.tar.gz | |
x86/vsmp: Fix irq routing
Correct IRQ routing in case a vSMP box is detected but the Interrupt Routing Comply (IRC) value is set to "comply", which leads to incorrect IRQ routing. Before the patch: When a vSMP box was detected and IRC was set to "comply", users (and the kernel) couldn't effectively set the destination of the IRQs. This is because the hook inside vsmp_64.c always setup all CPUs as the IRQ destination using cpumask_setall() as the return value for IRQ allocation mask. Later, this "overrided" mask caused the kernel to set the IRQ destination to the lowest online CPU in the mask (CPU0 usually). After the patch: When the IRC is set to "comply", users (and the kernel) can control the destination of the IRQs as we will not be changing the default "apic->vector_allocation_domain". Signed-off-by: Oren Twaig <oren@scalemp.com> Acked-by: Shai Fultheim <shai@scalemp.com> Link: http://lkml.kernel.org/r/1398669697-2123-1-git-send-email-oren@scalemp.com [ Minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/vsmp_64.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c index f6584a90aba3..5edc34b5b951 100644 --- a/arch/x86/kernel/vsmp_64.c +++ b/arch/x86/kernel/vsmp_64.c @@ -26,6 +26,9 @@ #define TOPOLOGY_REGISTER_OFFSET 0x10 +/* Flag below is initialized once during vSMP PCI initialization. */ +static int irq_routing_comply = 1; + #if defined CONFIG_PCI && defined CONFIG_PARAVIRT /* * Interrupt control on vSMPowered systems: @@ -101,6 +104,10 @@ static void __init set_vsmp_pv_ops(void) #ifdef CONFIG_SMP if (cap & ctl & BIT(8)) { ctl &= ~BIT(8); + + /* Interrupt routing set to ignore */ + irq_routing_comply = 0; + #ifdef CONFIG_PROC_FS /* Don't let users change irq affinity via procfs */ no_irq_affinity = 1; @@ -218,7 +225,9 @@ static void vsmp_apic_post_init(void) { /* need to update phys_pkg_id */ apic->phys_pkg_id = apicid_phys_pkg_id; - apic->vector_allocation_domain = fill_vector_allocation_domain; + + if (!irq_routing_comply) + apic->vector_allocation_domain = fill_vector_allocation_domain; } void __init vsmp_init(void) |