From 65d7ed57bd9708d562a37fa3f99bf9fd62052b9e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx@linutronix.de> Date: Wed, 13 Sep 2017 23:29:39 +0200 Subject: [PATCH] x86/vector: Add vector domain debugfs support Add the debug callback for the vector domain, which gives a detailed information about vector usage if invoked for the domain by using rhe matrix allocator debug function and vector/target information when invoked for a particular interrupt. Extra information foir the Vector domain: Online bitmaps: 32 Global available: 6352 Global reserved: 5 Total allocated: 20 System: 41: 0-19,32,50,128,238-255 | CPU | avl | man | act | vectors 0 183 4 19 33-48,51-53 1 199 4 1 33 2 199 4 0 Extra information for interrupts: Vector: 42 Target: 4 This allows a detailed analysis of the vector usage and the association to interrupts and devices. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Len Brown <lenb@kernel.org> Link: https://lkml.kernel.org/r/20170913213155.188137174@linutronix.de --- arch/x86/kernel/apic/vector.c | 50 +++++++++++++++++++++++++++++++++-- 1 file changed, 48 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index 078fbd08499c3..acdc74df649dc 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -11,6 +11,7 @@ * published by the Free Software Foundation. */ #include <linux/interrupt.h> +#include <linux/seq_file.h> #include <linux/init.h> #include <linux/compiler.h> #include <linux/slab.h> @@ -373,9 +374,54 @@ static int x86_vector_alloc_irqs(struct irq_domain *domain, unsigned int virq, return err; } +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS +void x86_vector_debug_show(struct seq_file *m, struct irq_domain *d, + struct irq_data *irqd, int ind) +{ + unsigned int cpu, vec, prev_cpu, prev_vec; + struct apic_chip_data *apicd; + unsigned long flags; + int irq; + + if (!irqd) { + irq_matrix_debug_show(m, vector_matrix, ind); + return; + } + + irq = irqd->irq; + if (irq < nr_legacy_irqs() && !test_bit(irq, &io_apic_irqs)) { + seq_printf(m, "%*sVector: %5d\n", ind, "", ISA_IRQ_VECTOR(irq)); + seq_printf(m, "%*sTarget: Legacy PIC all CPUs\n", ind, ""); + return; + } + + apicd = irqd->chip_data; + if (!apicd) { + seq_printf(m, "%*sVector: Not assigned\n", ind, ""); + return; + } + + raw_spin_lock_irqsave(&vector_lock, flags); + cpu = apicd->cpu; + vec = apicd->cfg.vector; + prev_cpu = apicd->prev_cpu; + prev_vec = apicd->cfg.old_vector; + raw_spin_unlock_irqrestore(&vector_lock, flags); + seq_printf(m, "%*sVector: %5u\n", ind, "", vec); + seq_printf(m, "%*sTarget: %5u\n", ind, "", cpu); + if (prev_vec) { + seq_printf(m, "%*sPrevious vector: %5u\n", ind, "", prev_vec); + seq_printf(m, "%*sPrevious target: %5u\n", ind, "", prev_cpu); + } +} +#endif + static const struct irq_domain_ops x86_vector_domain_ops = { - .alloc = x86_vector_alloc_irqs, - .free = x86_vector_free_irqs, + .alloc = x86_vector_alloc_irqs, + .free = x86_vector_free_irqs, +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS + .debug_show = x86_vector_debug_show, +#endif }; int __init arch_probe_nr_irqs(void)