1 files changed, 52 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index a6d19e3a505e..d345bfd56bbe 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -273,6 +273,58 @@ static struct notifier_block pci_dn_reconfig_nb = {
         .notifier_call = pci_dn_reconfig_notifier,
 };
 
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+/*
+ * Allocate space for the dispatch trace log for all possible cpus
+ * and register the buffers with the hypervisor.  This is used for
+ * computing time stolen by the hypervisor.
+ */
+static int alloc_dispatch_logs(void)
+{
+        int cpu, ret;
+        struct paca_struct *pp;
+        struct dtl_entry *dtl;
+
+        if (!firmware_has_feature(FW_FEATURE_SPLPAR))
+                return 0;
+
+        for_each_possible_cpu(cpu) {
+                pp = &paca[cpu];
+                dtl = kmalloc_node(DISPATCH_LOG_BYTES, GFP_KERNEL,
+                                   cpu_to_node(cpu));
+                if (!dtl) {
+                        pr_warn("Failed to allocate dispatch trace log for cpu %d\n",
+                                cpu);
+                        pr_warn("Stolen time statistics will be unreliable\n");
+                        break;
+                }
+
+                pp->dtl_ridx = 0;
+                pp->dispatch_log = dtl;
+                pp->dispatch_log_end = dtl + N_DISPATCH_LOG;
+                pp->dtl_curr = dtl;
+        }
+
+        /* Register the DTL for the current (boot) cpu */
+        dtl = get_paca()->dispatch_log;
+        get_paca()->dtl_ridx = 0;
+        get_paca()->dtl_curr = dtl;
+        get_paca()->lppaca_ptr->dtl_idx = 0;
+
+        /* hypervisor reads buffer length from this field */
+        dtl->enqueue_to_dispatch_time = DISPATCH_LOG_BYTES;
+        ret = register_dtl(hard_smp_processor_id(), __pa(dtl));
+        if (ret)
+                pr_warn("DTL registration failed for boot cpu %d (%d)\n",
+                        smp_processor_id(), ret);
+        get_paca()->lppaca_ptr->dtl_enable_mask = 2;
+
+        return 0;
+}
+
+early_initcall(alloc_dispatch_logs);
+#endif /* CONFIG_VIRT_CPU_ACCOUNTING */
+
 static void __init pSeries_setup_arch(void)
 {
         /* Discover PIC type and setup ppc_md accordingly */