have architectures specify the number of PIRQs a hardware domain gets The current value of nr_static_irqs + 256 is often too small for larger systems. Make it dependent on CPU count and number of IO-APIC pins on x86, and (until it obtains PCI support) simply NR_IRQS on ARM. Signed-off-by: Jan Beulich --- This is meant to be an alternative proposal to David's: http://lists.xenproject.org/archives/html/xen-devel/2014-12/msg00421.html --- a/docs/misc/xen-command-line.markdown +++ b/docs/misc/xen-command-line.markdown @@ -596,13 +596,14 @@ Force or disable use of EFI runtime serv ### extra\_guest\_irqs > `= [][,]` -> Default: `32,256` +> Default: `32,` Change the number of PIRQs available for guests. The optional first number is common for all domUs, while the optional second number (preceded by a comma) is for dom0. Changing the setting for domU has no impact on dom0 and vice versa. For example to change dom0 without changing domU, use -`extra_guest_irqs=,512` +`extra_guest_irqs=,512`. The default value for Dom0 and an eventual separate +hardware domain is architecture dependent. ### flask\_enabled > `= ` --- a/xen/arch/x86/domain_build.c +++ b/xen/arch/x86/domain_build.c @@ -101,7 +101,7 @@ static void __init parse_dom0_max_vcpus( } custom_param("dom0_max_vcpus", parse_dom0_max_vcpus); -struct vcpu *__init alloc_dom0_vcpu0(struct domain *dom0) +unsigned int __init dom0_max_vcpus(void) { unsigned max_vcpus; @@ -113,6 +113,13 @@ struct vcpu *__init alloc_dom0_vcpu0(str if ( max_vcpus > MAX_VIRT_CPUS ) max_vcpus = MAX_VIRT_CPUS; + return max_vcpus; +} + +struct vcpu *__init alloc_dom0_vcpu0(struct domain *dom0) +{ + unsigned int max_vcpus = dom0_max_vcpus(); + dom0->vcpu = xzalloc_array(struct vcpu *, max_vcpus); if ( !dom0->vcpu ) return NULL; --- a/xen/arch/x86/io_apic.c +++ b/xen/arch/x86/io_apic.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -2606,3 +2607,14 @@ void __init init_ioapic_mappings(void) nr_irqs_gsi, nr_irqs - nr_irqs_gsi); } +unsigned int arch_hwdom_irqs(domid_t domid) +{ + unsigned int n = fls(num_present_cpus()); + + if ( !domid ) + n = min(n, dom0_max_vcpus()); + n = min(nr_irqs_gsi + n * NR_DYNAMIC_VECTORS, nr_irqs); + printk("Dom%d has maximum %u PIRQs\n", domid, n); + + return n; +} --- a/xen/common/domain.c +++ b/xen/common/domain.c @@ -231,14 +231,14 @@ static int late_hwdom_init(struct domain #endif } -static unsigned int __read_mostly extra_dom0_irqs = 256; +static unsigned int __read_mostly extra_hwdom_irqs; static unsigned int __read_mostly extra_domU_irqs = 32; static void __init parse_extra_guest_irqs(const char *s) { if ( isdigit(*s) ) extra_domU_irqs = simple_strtoul(s, &s, 0); if ( *s == ',' && isdigit(*++s) ) - extra_dom0_irqs = simple_strtoul(s, &s, 0); + extra_hwdom_irqs = simple_strtoul(s, &s, 0); } custom_param("extra_guest_irqs", parse_extra_guest_irqs); @@ -326,7 +326,8 @@ struct domain *domain_create( if ( !is_hardware_domain(d) ) d->nr_pirqs = nr_static_irqs + extra_domU_irqs; else - d->nr_pirqs = nr_static_irqs + extra_dom0_irqs; + d->nr_pirqs = extra_hwdom_irqs ? nr_static_irqs + extra_hwdom_irqs + : arch_hwdom_irqs(domid); if ( d->nr_pirqs > nr_irqs ) d->nr_pirqs = nr_irqs; --- a/xen/include/asm-arm/irq.h +++ b/xen/include/asm-arm/irq.h @@ -21,10 +21,10 @@ struct arch_irq_desc { #define NR_LOCAL_IRQS 32 #define NR_IRQS 1024 -#define nr_irqs NR_IRQS #define nr_irqs NR_IRQS #define nr_static_irqs NR_IRQS +#define arch_hwdom_irqs(domid) NR_IRQS struct irq_desc; struct irqaction; --- a/xen/include/asm-x86/setup.h +++ b/xen/include/asm-x86/setup.h @@ -35,6 +35,8 @@ int construct_dom0( unsigned long initial_images_nrpages(void); void discard_initial_images(void); +unsigned int dom0_max_vcpus(void); + int xen_in_range(unsigned long mfn); void microcode_grab_module( --- a/xen/include/xen/irq.h +++ b/xen/include/xen/irq.h @@ -168,4 +168,8 @@ static inline void set_native_irq_info(u unsigned int set_desc_affinity(struct irq_desc *, const cpumask_t *); +#ifndef arch_hwdom_irqs +unsigned int arch_hwdom_irqs(domid_t); +#endif + #endif /* __XEN_IRQ_H__ */