From 7ccb4a662462616f6be5053e26b79580e02f1529 Mon Sep 17 00:00:00 2001 From: Mohan Kumar M Date: Wed, 13 Jun 2007 00:51:57 +1000 Subject: [POWERPC] Fix interrupt distribution in ppc970 In some of the PPC970 based systems, interrupt would be distributed to offline cpus also even when booted with "maxcpus=1". So check whether cpu online map and cpu present map are equal or not. If they are equal default_distrib_server is used as interrupt server otherwise boot cpu (default_server) used as interrupt server. In addition to this, if an interrupt is assigned to a specific cpu (ie smp affinity) and if that cpu is not online, the earlier code used to return the default_distrib_server as interrupt server. This introduces an additional parameter to the get_irq function, called strict_check. Based on this parameter, if the cpu is not online either default_distrib_server or -1 is returned. Signed-off-by: Mohan Kumar M Cc: Michael Ellerman Acked-by: Milton Miller Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/pseries/xics.c | 53 +++++++++++++++++++---------------- 1 file changed, 29 insertions(+), 24 deletions(-) (limited to 'arch') diff --git a/arch/powerpc/platforms/pseries/xics.c b/arch/powerpc/platforms/pseries/xics.c index f1df942072b..5bd90a7eb76 100644 --- a/arch/powerpc/platforms/pseries/xics.c +++ b/arch/powerpc/platforms/pseries/xics.c @@ -156,9 +156,9 @@ static inline void lpar_qirr_info(int n_cpu , u8 value) #ifdef CONFIG_SMP -static int get_irq_server(unsigned int virq) +static int get_irq_server(unsigned int virq, unsigned int strict_check) { - unsigned int server; + int server; /* For the moment only implement delivery to all cpus or one cpu */ cpumask_t cpumask = irq_desc[virq].affinity; cpumask_t tmp = CPU_MASK_NONE; @@ -166,22 +166,25 @@ static int get_irq_server(unsigned int virq) if (!distribute_irqs) return default_server; - if (cpus_equal(cpumask, CPU_MASK_ALL)) { - server = default_distrib_server; - } else { + if (!cpus_equal(cpumask, CPU_MASK_ALL)) { cpus_and(tmp, cpu_online_map, cpumask); - if (cpus_empty(tmp)) - server = default_distrib_server; - else - server = get_hard_smp_processor_id(first_cpu(tmp)); + server = first_cpu(tmp); + + if (server < NR_CPUS) + return get_hard_smp_processor_id(server); + + if (strict_check) + return -1; } - return server; + if (cpus_equal(cpu_online_map, cpu_present_map)) + return default_distrib_server; + return default_server; } #else -static int get_irq_server(unsigned int virq) +static int get_irq_server(unsigned int virq, unsigned int strict_check) { return default_server; } @@ -192,7 +195,7 @@ static void xics_unmask_irq(unsigned int virq) { unsigned int irq; int call_status; - unsigned int server; + int server; pr_debug("xics: unmask virq %d\n", virq); @@ -201,7 +204,7 @@ static void xics_unmask_irq(unsigned int virq) if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS) return; - server = get_irq_server(virq); + server = get_irq_server(virq, 0); call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server, DEFAULT_PRIORITY); @@ -398,8 +401,7 @@ static void xics_set_affinity(unsigned int virq, cpumask_t cpumask) unsigned int irq; int status; int xics_status[2]; - unsigned long newmask; - cpumask_t tmp = CPU_MASK_NONE; + int irq_server; irq = (unsigned int)irq_map[virq].hwirq; if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS) @@ -413,18 +415,21 @@ static void xics_set_affinity(unsigned int virq, cpumask_t cpumask) return; } - /* For the moment only implement delivery to all cpus or one cpu */ - if (cpus_equal(cpumask, CPU_MASK_ALL)) { - newmask = default_distrib_server; - } else { - cpus_and(tmp, cpu_online_map, cpumask); - if (cpus_empty(tmp)) - return; - newmask = get_hard_smp_processor_id(first_cpu(tmp)); + /* + * For the moment only implement delivery to all cpus or one cpu. + * Get current irq_server for the given irq + */ + irq_server = get_irq_server(irq, 1); + if (irq_server == -1) { + char cpulist[128]; + cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask); + printk(KERN_WARNING "xics_set_affinity: No online cpus in " + "the mask %s for irq %d\n", cpulist, virq); + return; } status = rtas_call(ibm_set_xive, 3, 1, NULL, - irq, newmask, xics_status[1]); + irq, irq_server, xics_status[1]); if (status) { printk(KERN_ERR "xics_set_affinity: irq=%u ibm,set-xive " -- cgit v1.2.3