KVM: PPC: Book3S PR: Add transaction memory save/restore skeleton

The transaction memory checkpoint area save/restore behavior is
triggered when VCPU qemu process is switching out/into CPU, i.e.
at kvmppc_core_vcpu_put_pr() and kvmppc_core_vcpu_load_pr().

MSR TM active state is determined by TS bits:
    active: 10(transactional) or 01 (suspended)
    inactive: 00 (non-transactional)
We don't "fake" TM functionality for guest. We "sync" guest virtual
MSR TM active state(10 or 01) with shadow MSR. That is to say,
we don't emulate a transactional guest with a TM inactive MSR.

TM SPR support(TFIAR/TFAR/TEXASR) has already been supported by
commit 9916d57e64 ("KVM: PPC: Book3S PR: Expose TM registers").
Math register support (FPR/VMX/VSX) will be done at subsequent
patch.

Whether TM context need to be saved/restored can be determined
by kvmppc_get_msr() TM active state:
	* TM active - save/restore TM context
	* TM inactive - no need to do so and only save/restore
TM SPRs.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Simon Guo
2018-05-23 15:01:58 +08:00
committed by Paul Mackerras
parent 66c33e796c
commit 8d2e2fc5e0
3 changed files with 36 additions and 1 deletions

View File

@@ -257,6 +257,15 @@ extern int kvmppc_hcall_impl_pr(unsigned long cmd);
extern int kvmppc_hcall_impl_hv_realmode(unsigned long cmd);
extern void kvmppc_copy_to_svcpu(struct kvm_vcpu *vcpu);
extern void kvmppc_copy_from_svcpu(struct kvm_vcpu *vcpu);
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu);
void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu);
#else
static inline void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu) {}
static inline void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu) {}
#endif
extern int kvm_irq_bypass;
static inline struct kvmppc_vcpu_book3s *to_book3s(struct kvm_vcpu *vcpu)