[PATCH AUTOSEL for 4.9 137/190] x86/xen: split xen_smp_prepare_boot_cpu()

From: Sasha Levin
Date: Thu Mar 08 2018 - 00:03:40 EST


From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

[ Upstream commit a2d1078a35f9a38ae888aa6147e4ca32666154a1 ]

Split xen_smp_prepare_boot_cpu() into xen_pv_smp_prepare_boot_cpu() and
xen_hvm_smp_prepare_boot_cpu() to support further splitting of smp.c.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
arch/x86/xen/smp.c | 49 ++++++++++++++++++++++++++++++-------------------
1 file changed, 30 insertions(+), 19 deletions(-)

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 137afbbd0590..a11540e51f62 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -299,35 +299,46 @@ static void __init xen_filter_cpu_maps(void)

}

-static void __init xen_smp_prepare_boot_cpu(void)
+static void __init xen_pv_smp_prepare_boot_cpu(void)
{
BUG_ON(smp_processor_id() != 0);
native_smp_prepare_boot_cpu();

- if (xen_pv_domain()) {
- if (!xen_feature(XENFEAT_writable_page_tables))
- /* We've switched to the "real" per-cpu gdt, so make
- * sure the old memory can be recycled. */
- make_lowmem_page_readwrite(xen_initial_gdt);
+ if (!xen_feature(XENFEAT_writable_page_tables))
+ /* We've switched to the "real" per-cpu gdt, so make
+ * sure the old memory can be recycled. */
+ make_lowmem_page_readwrite(xen_initial_gdt);

#ifdef CONFIG_X86_32
- /*
- * Xen starts us with XEN_FLAT_RING1_DS, but linux code
- * expects __USER_DS
- */
- loadsegment(ds, __USER_DS);
- loadsegment(es, __USER_DS);
+ /*
+ * Xen starts us with XEN_FLAT_RING1_DS, but linux code
+ * expects __USER_DS
+ */
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
#endif

- xen_filter_cpu_maps();
- xen_setup_vcpu_info_placement();
- }
+ xen_filter_cpu_maps();
+ xen_setup_vcpu_info_placement();
+
+ /*
+ * The alternative logic (which patches the unlock/lock) runs before
+ * the smp bootup up code is activated. Hence we need to set this up
+ * the core kernel is being patched. Otherwise we will have only
+ * modules patched but not core code.
+ */
+ xen_init_spinlocks();
+}
+
+static void __init xen_hvm_smp_prepare_boot_cpu(void)
+{
+ BUG_ON(smp_processor_id() != 0);
+ native_smp_prepare_boot_cpu();

/*
* Setup vcpu_info for boot CPU.
*/
- if (xen_hvm_domain())
- xen_vcpu_setup(0);
+ xen_vcpu_setup(0);

/*
* The alternative logic (which patches the unlock/lock) runs before
@@ -733,7 +744,7 @@ static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
}

static const struct smp_ops xen_smp_ops __initconst = {
- .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
+ .smp_prepare_boot_cpu = xen_pv_smp_prepare_boot_cpu,
.smp_prepare_cpus = xen_smp_prepare_cpus,
.smp_cpus_done = xen_smp_cpus_done,

@@ -772,5 +783,5 @@ void __init xen_hvm_smp_init(void)
smp_ops.cpu_die = xen_cpu_die;
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;
+ smp_ops.smp_prepare_boot_cpu = xen_hvm_smp_prepare_boot_cpu;
}
--
2.14.1