From: Simon Guo <wei.guo.simon@xxxxxxxxx>
The transaction memory checkpoint area save/restore behavior is
triggered when VCPU qemu process is switching out/into CPU. ie.
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 9916d57e64a4 ("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@xxxxxxxxx>
Suggested-by: Paul Mackerras <paulus@xxxxxxxxxx>
---
arch/powerpc/include/asm/kvm_book3s.h | 9 +++++++++
arch/powerpc/include/asm/kvm_host.h | 1 -
arch/powerpc/kvm/book3s_pr.c | 27 +++++++++++++++++++++++++++
3 files changed, 36 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 20d3d5a..fc15ad9 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -257,6 +257,15 @@ extern void kvmppc_update_lpcr(struct kvm *kvm, unsigned long lpcr,
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)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 89f44ec..60325af 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -621,7 +621,6 @@ struct kvm_vcpu_arch {
struct thread_vr_state vr_tm;
u32 vrsave_tm; /* also USPRG0 */
-
#endif
#ifdef CONFIG_KVM_EXIT_TIMING
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index 7d4905a..226bae7 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -43,6 +43,7 @@
#include <linux/module.h>
#include <linux/miscdevice.h>
#include <asm/asm-prototypes.h>
+#include <asm/tm.h>
#include "book3s.h"
@@ -115,6 +116,8 @@ static void kvmppc_core_vcpu_load_pr(struct kvm_vcpu *vcpu, int cpu)
if (kvmppc_is_split_real(vcpu))
kvmppc_fixup_split_real(vcpu);
+
+ kvmppc_restore_tm_pr(vcpu);
}
static void kvmppc_core_vcpu_put_pr(struct kvm_vcpu *vcpu)
@@ -134,6 +137,7 @@ static void kvmppc_core_vcpu_put_pr(struct kvm_vcpu *vcpu)
kvmppc_giveup_ext(vcpu, MSR_FP | MSR_VEC | MSR_VSX);
kvmppc_giveup_fac(vcpu, FSCR_TAR_LG);
+ kvmppc_save_tm_pr(vcpu);
/* Enable AIL if supported */
if (cpu_has_feature(CPU_FTR_HVMODE) &&
@@ -304,6 +308,29 @@ static inline void kvmppc_restore_tm_sprs(struct kvm_vcpu *vcpu)
tm_disable();
}
+void kvmppc_save_tm_pr(struct kvm_vcpu *vcpu)
+{
+ if (!(MSR_TM_ACTIVE(kvmppc_get_msr(vcpu)))) {
+ kvmppc_save_tm_sprs(vcpu);
+ return;
+ }
+
+ preempt_disable();
+ _kvmppc_save_tm_pr(vcpu, mfmsr());
+ preempt_enable();
+}
+
+void kvmppc_restore_tm_pr(struct kvm_vcpu *vcpu)
+{
+ if (!MSR_TM_ACTIVE(kvmppc_get_msr(vcpu))) {
+ kvmppc_restore_tm_sprs(vcpu);
+ return;
+ }
+
+ preempt_disable();
+ _kvmppc_restore_tm_pr(vcpu, kvmppc_get_msr(vcpu));
+ preempt_enable();
+}
#endif
static int kvmppc_core_check_requests_pr(struct kvm_vcpu *vcpu)
--
1.8.3.1
