From ea375f9ab8c76686dca0af8cb4f87a4eb569cad3 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 1 Mar 2010 19:10:30 +0100 Subject: KVM: Rework VCPU state writeback API This grand cleanup drops all reset and vmsave/load related synchronization points in favor of four(!) generic hooks: - cpu_synchronize_all_states in qemu_savevm_state_complete (initial sync from kernel before vmsave) - cpu_synchronize_all_post_init in qemu_loadvm_state (writeback after vmload) - cpu_synchronize_all_post_init in main after machine init - cpu_synchronize_all_post_reset in qemu_system_reset (writeback after system reset) These writeback points + the existing one of VCPU exec after cpu_synchronize_state map on three levels of writeback: - KVM_PUT_RUNTIME_STATE (during runtime, other VCPUs continue to run) - KVM_PUT_RESET_STATE (on synchronous system reset, all VCPUs stopped) - KVM_PUT_FULL_STATE (on init or vmload, all VCPUs stopped as well) This level is passed to the arch-specific VCPU state writing function that will decide which concrete substates need to be written. That way, no writer of load, save or reset functions that interact with in-kernel KVM states will ever have to worry about synchronization again. That also means that a lot of reasons for races, segfaults and deadlocks are eliminated. cpu_synchronize_state remains untouched, just as Anthony suggested. We continue to need it before reading or writing of VCPU states that are also tracked by in-kernel KVM subsystems. Consequently, this patch removes many cpu_synchronize_state calls that are now redundant, just like remaining explicit register syncs. Signed-off-by: Jan Kiszka Signed-off-by: Marcelo Tosatti --- target-ppc/machine.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'target-ppc/machine.c') diff --git a/target-ppc/machine.c b/target-ppc/machine.c index 4897c8a4d3..67de951959 100644 --- a/target-ppc/machine.c +++ b/target-ppc/machine.c @@ -7,8 +7,6 @@ void cpu_save(QEMUFile *f, void *opaque) CPUState *env = (CPUState *)opaque; unsigned int i, j; - cpu_synchronize_state(env); - for (i = 0; i < 32; i++) qemu_put_betls(f, &env->gpr[i]); #if !defined(TARGET_PPC64) @@ -96,8 +94,6 @@ int cpu_load(QEMUFile *f, void *opaque, int version_id) CPUState *env = (CPUState *)opaque; unsigned int i, j; - cpu_synchronize_state(env); - for (i = 0; i < 32; i++) qemu_get_betls(f, &env->gpr[i]); #if !defined(TARGET_PPC64) -- cgit v1.2.1