Commit-ID: 3aabb53ce5849605cee731bbc32f37120b4c4ceb Gitweb: http://git.kernel.org/tip/3aabb53ce5849605cee731bbc32f37120b4c4ceb Author: Ravikiran Thirumalai <kiran.thirumalai@xxxxxxxxx> AuthorDate: Sun, 3 Jun 2012 01:11:35 +0300 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Wed, 6 Jun 2012 09:06:20 +0200 x86/vsmp: Ignore IOAPIC IRQ affinity if possible vSMP can route interrupts more optimally based on internal knowledge the OS does not have. In order to support this optimization, all CPUs must be able to handle all possible IOAPIC interrupts. Fix this by setting the vector allocation domain for all CPUs and by enabling this feature in vSMP. Signed-off-by: Ravikiran Thirumalai <kiran.thirumalai@xxxxxxxxx> Signed-off-by: Shai Fultheim <shai@xxxxxxxxxxx> [ rebased, simplified, and reworded the commit message ] Signed-off-by: Ido Yariv <ido@xxxxxxxxxx> Link: http://lkml.kernel.org/r/1338675095-27260-2-git-send-email-ido@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/kernel/vsmp_64.c | 25 +++++++++++++++++++++---- 1 files changed, 21 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c index 59eea85..c72c0d3 100644 --- a/arch/x86/kernel/vsmp_64.c +++ b/arch/x86/kernel/vsmp_64.c @@ -16,6 +16,7 @@ #include <linux/pci_ids.h> #include <linux/pci_regs.h> #include <linux/smp.h> +#include <linux/irq.h> #include <asm/apic.h> #include <asm/pci-direct.h> @@ -95,6 +96,13 @@ static void __init set_vsmp_pv_ops(void) ctl = readl(address + 4); printk(KERN_INFO "vSMP CTL: capabilities:0x%08x control:0x%08x\n", cap, ctl); + + /* If possible, let the vSMP foundation route the interrupt optimally */ + if (cap & ctl & BIT(8)) { + ctl &= ~BIT(8); + no_irq_affinity = 1; + } + if (cap & ctl & (1 << 4)) { /* Setup irq ops and turn on vSMP IRQ fastpath handling */ pv_irq_ops.irq_disable = PV_CALLEE_SAVE(vsmp_irq_disable); @@ -102,12 +110,11 @@ static void __init set_vsmp_pv_ops(void) pv_irq_ops.save_fl = PV_CALLEE_SAVE(vsmp_save_fl); pv_irq_ops.restore_fl = PV_CALLEE_SAVE(vsmp_restore_fl); pv_init_ops.patch = vsmp_patch; - ctl &= ~(1 << 4); - writel(ctl, address + 4); - ctl = readl(address + 4); - printk(KERN_INFO "vSMP CTL: control set to:0x%08x\n", ctl); } + writel(ctl, address + 4); + ctl = readl(address + 4); + pr_info("vSMP CTL: control set to:0x%08x\n", ctl); early_iounmap(address, 8); } @@ -192,10 +199,20 @@ static int apicid_phys_pkg_id(int initial_apic_id, int index_msb) return hard_smp_processor_id() >> index_msb; } +/* + * In vSMP, all cpus should be capable of handling interrupts, regardless of + * the APIC used. + */ +static void fill_vector_allocation_domain(int cpu, struct cpumask *retmask) +{ + cpumask_setall(retmask); +} + 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; } void __init vsmp_init(void) -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html