powerpc/cpumask: Convert xics driver to new cpumask API

Use the new cpumask API and add some comments to clarify how get_irq_server
works.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 21 insertions, 17 deletions

diff --git a/arch/powerpc/platforms/pseries/xics.c b/arch/powerpc/platforms/pseries/xics.c
index 1bcedd8b4616..f19d19468393 100644
--- a/arch/powerpc/platforms/pseries/xics.c
+++ b/arch/powerpc/platforms/pseries/xics.c
@@ -163,29 +163,37 @@ static inline void lpar_qirr_info(int n_cpu , u8 value)
 /* Interface to generic irq subsystem */
 
 #ifdef CONFIG_SMP
-static int get_irq_server(unsigned int virq, cpumask_t cpumask,
+/*
+ * For the moment we only implement delivery to all cpus or one cpu.
+ *
+ * If the requested affinity is cpu_all_mask, we set global affinity.
+ * If not we set it to the first cpu in the mask, even if multiple cpus
+ * are set. This is so things like irqbalance (which set core and package
+ * wide affinities) do the right thing.
+ */
+static int get_irq_server(unsigned int virq, const struct cpumask *cpumask,
                           unsigned int strict_check)
 {
-        int server;
-        /* For the moment only implement delivery to all cpus or one cpu */
-        cpumask_t tmp = CPU_MASK_NONE;
 
         if (!distribute_irqs)
                 return default_server;
 
-        if (!cpus_equal(cpumask, CPU_MASK_ALL)) {
-                cpus_and(tmp, cpu_online_map, cpumask);
-
-                server = first_cpu(tmp);
+        if (!cpumask_equal(cpumask, cpu_all_mask)) {
+                int server = cpumask_first_and(cpu_online_mask, cpumask);
 
-                if (server < NR_CPUS)
+                if (server < nr_cpu_ids)
                         return get_hard_smp_processor_id(server);
 
                 if (strict_check)
                         return -1;
         }
 
-        if (cpus_equal(cpu_online_map, cpu_present_map))
+        /*
+         * Workaround issue with some versions of JS20 firmware that
+         * deliver interrupts to cpus which haven't been started. This
+         * happens when using the maxcpus= boot option.
+         */
+        if (cpumask_equal(cpu_online_mask, cpu_present_mask))
                 return default_distrib_server;
 
         return default_server;
@@ -207,7 +215,7 @@ static void xics_unmask_irq(unsigned int virq)
         if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
                 return;
 
-        server = get_irq_server(virq, *(irq_to_desc(virq)->affinity), 0);
+        server = get_irq_server(virq, irq_to_desc(virq)->affinity, 0);
 
         call_status = rtas_call(ibm_set_xive, 3, 1, NULL, irq, server,
                                 DEFAULT_PRIORITY);
@@ -398,11 +406,7 @@ static int xics_set_affinity(unsigned int virq, const struct cpumask *cpumask)
                 return -1;
         }
 
-        /*
-         * 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(virq, *cpumask, 1);
+        irq_server = get_irq_server(virq, cpumask, 1);
         if (irq_server == -1) {
                 char cpulist[128];
                 cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask);
@@ -611,7 +615,7 @@ int __init smp_xics_probe(void)
 {
         xics_request_ipi();
 
-        return cpus_weight(cpu_possible_map);
+        return cpumask_weight(cpu_possible_mask);
 }
 
 #endif /* CONFIG_SMP */