| Message ID | 1384504501-19348-2-git-send-email-pingfank@linux.vnet.ibm.com |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Nov 15, 2013 at 04:35:01PM +0800, Liu Ping Fan wrote: > > +sc_1_fast_return: > + mtspr SPRN_SRR0,r10 > + mtspr SPRN_SRR1,r11 > + li r10, BOOK3S_INTERRUPT_SYSCALL > + li r11, (MSR_ME << 1) | 1 /* synthesize MSR_SF | MSR_ME */ > + rotldi r11, r11, 63 You need a "mr r4, r9" instruction here, because fast_guest_return needs the vcpu pointer in r4. Apart from that this looks fine. > + b fast_guest_return Paul. -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Nov 16, 2013 at 3:00 PM, Paul Mackerras <paulus@samba.org> wrote: > On Fri, Nov 15, 2013 at 04:35:01PM +0800, Liu Ping Fan wrote: >> >> +sc_1_fast_return: >> + mtspr SPRN_SRR0,r10 >> + mtspr SPRN_SRR1,r11 >> + li r10, BOOK3S_INTERRUPT_SYSCALL >> + li r11, (MSR_ME << 1) | 1 /* synthesize MSR_SF | MSR_ME */ >> + rotldi r11, r11, 63 > > You need a "mr r4, r9" instruction here, because fast_guest_return > needs the vcpu pointer in r4. Apart from that this looks fine. > Will fix it. Thanks and regards, Pingfan >> + b fast_guest_return > > Paul. -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 62a2b5a..73dc852 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -628,12 +628,6 @@ static int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, /* hcall - punt to userspace */ int i; - if (vcpu->arch.shregs.msr & MSR_PR) { - /* sc 1 from userspace - reflect to guest syscall */ - kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_SYSCALL); - r = RESUME_GUEST; - break; - } run->papr_hcall.nr = kvmppc_get_gpr(vcpu, 3); for (i = 0; i < 9; ++i) run->papr_hcall.args[i] = kvmppc_get_gpr(vcpu, 4 + i); diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index c71103b..a463f08 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1388,7 +1388,8 @@ kvmppc_hisi: hcall_try_real_mode: ld r3,VCPU_GPR(R3)(r9) andi. r0,r11,MSR_PR - bne guest_exit_cont + /* sc 1 from userspace - reflect to guest syscall */ + bne sc_1_fast_return clrrdi r3,r3,2 cmpldi r3,hcall_real_table_end - hcall_real_table bge guest_exit_cont @@ -1409,6 +1410,14 @@ hcall_try_real_mode: ld r11,VCPU_MSR(r4) b fast_guest_return +sc_1_fast_return: + mtspr SPRN_SRR0,r10 + mtspr SPRN_SRR1,r11 + li r10, BOOK3S_INTERRUPT_SYSCALL + li r11, (MSR_ME << 1) | 1 /* synthesize MSR_SF | MSR_ME */ + rotldi r11, r11, 63 + b fast_guest_return + /* We've attempted a real mode hcall, but it's punted it back * to userspace. We need to restore some clobbered volatiles * before resuming the pass-it-to-qemu path */
In some scene, e.g openstack CI, PR guest can trigger "sc 1" frequently, this patch optimizes the path by directly delivering BOOK3S_INTERRUPT_SYSCALL to HV guest, so powernv can return to HV guest without heavy exit, i.e, no need to swap TLB, HTAB,.. etc Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com> --- arch/powerpc/kvm/book3s_hv.c | 6 ------ arch/powerpc/kvm/book3s_hv_rmhandlers.S | 11 ++++++++++- 2 files changed, 10 insertions(+), 7 deletions(-)