[PATCH v2 10/11] xen/hvmlite: Boot secondary CPUs

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

HVMlite secondary VCPUs use baremetal bringup path (i.e. native_*
smp_ops) but need to do some preparation in PV code.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
 arch/x86/xen/enlighten.c |    2 +
 arch/x86/xen/pmu.c       |    4 +-
 arch/x86/xen/smp.c       |   64 +++++++++++++++++++++++++++++++++------------
 3 files changed, 51 insertions(+), 19 deletions(-)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 1409de6..76fb0b2 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1933,6 +1933,8 @@ static void __init xen_hvm_guest_init(void)
 		xen_have_vector_callback = 1;
 	xen_hvm_smp_init();
 	register_cpu_notifier(&xen_hvm_cpu_notifier);
+	if (xen_hvmlite)
+		smp_found_config = 1;
 	xen_unplug_emulated_devices();
 	x86_init.irqs.intr_init = xen_init_IRQ;
 	xen_hvm_init_time_ops();
diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c
index 724a087..7bc209b 100644
--- a/arch/x86/xen/pmu.c
+++ b/arch/x86/xen/pmu.c
@@ -518,7 +518,7 @@ void xen_pmu_init(int cpu)
 
 	BUILD_BUG_ON(sizeof(struct xen_pmu_data) > PAGE_SIZE);
 
-	if (xen_hvm_domain())
+	if (xen_hvm_domain() && !xen_hvmlite)
 		return;
 
 	xenpmu_data = (struct xen_pmu_data *)get_zeroed_page(GFP_KERNEL);
@@ -556,7 +556,7 @@ void xen_pmu_finish(int cpu)
 {
 	struct xen_pmu_params xp;
 
-	if (xen_hvm_domain())
+	if (xen_hvm_domain() && !xen_hvmlite)
 		return;
 
 	xp.vcpu = cpu;
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index fb085ef..a22cae2 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -348,26 +348,31 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 	}
 	xen_init_lock_cpu(0);
 
-	smp_store_boot_cpu_info();
-	cpu_data(0).x86_max_cores = 1;
+	if (!xen_hvmlite) {
+		smp_store_boot_cpu_info();
+		cpu_data(0).x86_max_cores = 1;
+
+		for_each_possible_cpu(i) {
+			zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i),
+					   GFP_KERNEL);
+			zalloc_cpumask_var(&per_cpu(cpu_core_map, i),
+					   GFP_KERNEL);
+			zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i),
+					   GFP_KERNEL);
+		}
+		set_cpu_sibling_map(0);
 
-	for_each_possible_cpu(i) {
-		zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
-		zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
-		zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
+		if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
+			panic("could not allocate xen_cpu_initialized_map\n");
+
+		cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
 	}
-	set_cpu_sibling_map(0);
 
 	xen_pmu_init(0);
 
 	if (xen_smp_intr_init(0))
 		BUG();
 
-	if (!alloc_cpumask_var(&xen_cpu_initialized_map, GFP_KERNEL))
-		panic("could not allocate xen_cpu_initialized_map\n");
-
-	cpumask_copy(xen_cpu_initialized_map, cpumask_of(0));
-
 	/* Restrict the possible_map according to max_cpus. */
 	while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
 		for (cpu = nr_cpu_ids - 1; !cpu_possible(cpu); cpu--)
@@ -375,8 +380,11 @@ static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 		set_cpu_possible(cpu, false);
 	}
 
-	for_each_possible_cpu(cpu)
+	for_each_possible_cpu(cpu) {
 		set_cpu_present(cpu, true);
+		if (xen_hvmlite)
+			physid_set(cpu, phys_cpu_present_map);
+	}
 }
 
 static int
@@ -810,10 +818,15 @@ void __init xen_smp_init(void)
 
 static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
 {
+	if (xen_hvmlite)
+		xen_smp_prepare_cpus(max_cpus);
+
 	native_smp_prepare_cpus(max_cpus);
-	WARN_ON(xen_smp_intr_init(0));
 
-	xen_init_lock_cpu(0);
+	if (!xen_hvmlite) {
+		WARN_ON(xen_smp_intr_init(0));
+		xen_init_lock_cpu(0);
+	}
 }
 
 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
@@ -836,8 +849,21 @@ static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
 	*/
 	rc = xen_smp_intr_init(cpu);
 	WARN_ON(rc);
-	if (!rc)
-		rc =  native_cpu_up(cpu, tidle);
+
+	if (xen_hvmlite) {
+		rc = cpu_initialize_context(cpu, tidle);
+		if (rc) {
+			xen_smp_intr_free(cpu);
+			return rc;
+		}
+		xen_pmu_init(cpu);
+	}
+
+	if (!rc) {
+		rc = native_cpu_up(cpu, tidle);
+		if (rc && xen_hvmlite)
+			xen_pmu_finish(cpu);
+	}
 
 	/*
 	 * We must initialize the slowpath CPU kicker _after_ the native
@@ -861,4 +887,8 @@ void __init xen_hvm_smp_init(void)
 	smp_ops.send_call_func_ipi = xen_smp_send_call_function_ipi;
 	smp_ops.send_call_func_single_ipi = xen_smp_send_call_function_single_ipi;
 	smp_ops.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu;
+	if (xen_hvmlite) {
+		smp_ops.play_dead = xen_play_dead;
+		xen_fill_possible_map();
+	}
 }
-- 
1.7.1