From 0e91398f2a5d4eb6b07df8115917d0d1cf3e9b58 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 26 May 2008 23:31:27 +0100 Subject: xen: implement save/restore This patch implements Xen save/restore and migration. Saving is triggered via xenbus, which is polled in drivers/xen/manage.c. When a suspend request comes in, the kernel prepares itself for saving by: 1 - Freeze all processes. This is primarily to prevent any partially-completed pagetable updates from confusing the suspend process. If CONFIG_PREEMPT isn't defined, then this isn't necessary. 2 - Suspend xenbus and other devices 3 - Stop_machine, to make sure all the other vcpus are quiescent. The Xen tools require the domain to run its save off vcpu0. 4 - Within the stop_machine state, it pins any unpinned pgds (under construction or destruction), performs canonicalizes various other pieces of state (mostly converting mfns to pfns), and finally 5 - Suspend the domain Restore reverses the steps used to save the domain, ending when all the frozen processes are thawed. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Thomas Gleixner --- arch/x86/xen/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/xen/smp.c') diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 74ab8968c525..d2e3c20127d7 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -35,7 +35,7 @@ #include "xen-ops.h" #include "mmu.h" -static cpumask_t xen_cpu_initialized_map; +cpumask_t xen_cpu_initialized_map; static DEFINE_PER_CPU(int, resched_irq) = -1; static DEFINE_PER_CPU(int, callfunc_irq) = -1; static DEFINE_PER_CPU(int, debug_irq) = -1; -- cgit v1.2.3