* [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler
@ 2019-03-19 4:04 Suraj Jitindar Singh
2019-03-19 6:53 ` Alexey Kardashevskiy
2019-03-22 5:04 ` Suraj Jitindar Singh
0 siblings, 2 replies; 3+ messages in thread
From: Suraj Jitindar Singh @ 2019-03-19 4:04 UTC (permalink / raw)
To: kvm-ppc
Implement a virtual mode handler for the H_CALL H_PAGE_INIT which can be
used to zero or copy a guest page. The page is defined to be 4k and must
be 4k aligned.
The in-kernel handler halves the time to handle this H_CALL compared to
handling it in userspace for a radix guest.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
---
arch/powerpc/kvm/book3s_hv.c | 39 +++++++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 7179ea783f4f..fa29cc4900c2 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -883,6 +883,39 @@ static int kvmppc_copy_guest(struct kvm *kvm, gpa_t to, gpa_t from,
return 0;
}
+static int kvmppc_h_page_init(struct kvm_vcpu *vcpu, unsigned long flags,
+ unsigned long dest, unsigned long src)
+{
+ int ret = H_FUNCTION;
+ u64 pg_sz = 1UL << 12; /* 4K page size */
+ u64 pg_mask = pg_sz - 1;
+
+ /* Check for invalid flags (H_PAGE_SET_LOANED covers all CMO flags) */
+ if (flags & ~(H_ICACHE_INVALIDATE | H_ICACHE_SYNCHRONIZE |
+ H_ZERO_PAGE | H_COPY_PAGE | H_PAGE_SET_LOANED))
+ return H_PARAMETER;
+
+ /* dest (and src if copy_page flag set) must be page aligned */
+ if ((dest & pg_mask) || ((flags & H_COPY_PAGE) && (src & pg_mask)))
+ return H_PARAMETER;
+
+ /* zero and/or copy the page as determined by the flags */
+ if (flags & H_ZERO_PAGE) {
+ ret = kvm_clear_guest(vcpu->kvm, dest, pg_sz);
+ if (ret < 0)
+ return H_PARAMETER;
+ }
+ if (flags & H_COPY_PAGE) {
+ ret = kvmppc_copy_guest(vcpu->kvm, dest, src, pg_sz);
+ if (ret < 0)
+ return H_PARAMETER;
+ }
+
+ /* We can ignore the remaining flags */
+
+ return H_SUCCESS;
+}
+
static int kvm_arch_vcpu_yield_to(struct kvm_vcpu *target)
{
struct kvmppc_vcore *vcore = target->arch.vcore;
@@ -1083,6 +1116,11 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
if (nesting_enabled(vcpu->kvm))
ret = kvmhv_copy_tofrom_guest_nested(vcpu);
break;
+ case H_PAGE_INIT:
+ ret = kvmppc_h_page_init(vcpu, kvmppc_get_gpr(vcpu, 4),
+ kvmppc_get_gpr(vcpu, 5),
+ kvmppc_get_gpr(vcpu, 6));
+ break;
default:
return RESUME_HOST;
}
@@ -1127,6 +1165,7 @@ static int kvmppc_hcall_impl_hv(unsigned long cmd)
case H_IPOLL:
case H_XIRR_X:
#endif
+ case H_PAGE_INIT:
return 1;
}
--
2.13.6
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler
2019-03-19 4:04 [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler Suraj Jitindar Singh
@ 2019-03-19 6:53 ` Alexey Kardashevskiy
2019-03-22 5:04 ` Suraj Jitindar Singh
1 sibling, 0 replies; 3+ messages in thread
From: Alexey Kardashevskiy @ 2019-03-19 6:53 UTC (permalink / raw)
To: kvm-ppc
On 19/03/2019 15:04, Suraj Jitindar Singh wrote:
> Implement a virtual mode handler for the H_CALL H_PAGE_INIT which can be
> used to zero or copy a guest page. The page is defined to be 4k and must
> be 4k aligned.
>
> The in-kernel handler halves the time to handle this H_CALL compared to
> handling it in userspace for a radix guest.
>
> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> ---
> arch/powerpc/kvm/book3s_hv.c | 39 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 39 insertions(+)
>
> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
> index 7179ea783f4f..fa29cc4900c2 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -883,6 +883,39 @@ static int kvmppc_copy_guest(struct kvm *kvm, gpa_t to, gpa_t from,
> return 0;
> }
>
> +static int kvmppc_h_page_init(struct kvm_vcpu *vcpu, unsigned long flags,
> + unsigned long dest, unsigned long src)
> +{
> + int ret = H_FUNCTION;
> + u64 pg_sz = 1UL << 12; /* 4K page size */
> + u64 pg_mask = pg_sz - 1;
Ditch pg_sz and just use SZ_4K? The page size is not going to change
here ever.
> +
> + /* Check for invalid flags (H_PAGE_SET_LOANED covers all CMO flags) */
> + if (flags & ~(H_ICACHE_INVALIDATE | H_ICACHE_SYNCHRONIZE |
> + H_ZERO_PAGE | H_COPY_PAGE | H_PAGE_SET_LOANED))
> + return H_PARAMETER;
> +
> + /* dest (and src if copy_page flag set) must be page aligned */
> + if ((dest & pg_mask) || ((flags & H_COPY_PAGE) && (src & pg_mask)))
> + return H_PARAMETER;
> +
> + /* zero and/or copy the page as determined by the flags */
> + if (flags & H_ZERO_PAGE) {
> + ret = kvm_clear_guest(vcpu->kvm, dest, pg_sz);
> + if (ret < 0)
> + return H_PARAMETER;
> + }
> + if (flags & H_COPY_PAGE) {
If H_COPY_PAGE is set, is there any good reason to do kvm_clear_guest
first even if H_ZERO_PAGE is set? It should not happen in practice and
it is no harm but also no sense.
> + ret = kvmppc_copy_guest(vcpu->kvm, dest, src, pg_sz);
> + if (ret < 0)
> + return H_PARAMETER;
> + }
else if (src)
return H_PARAMETER;
> +
> + /* We can ignore the remaining flags */
> +
> + return H_SUCCESS;
> +}
> +
> static int kvm_arch_vcpu_yield_to(struct kvm_vcpu *target)
> {
> struct kvmppc_vcore *vcore = target->arch.vcore;
> @@ -1083,6 +1116,11 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
> if (nesting_enabled(vcpu->kvm))
> ret = kvmhv_copy_tofrom_guest_nested(vcpu);
> break;
> + case H_PAGE_INIT:
> + ret = kvmppc_h_page_init(vcpu, kvmppc_get_gpr(vcpu, 4),
> + kvmppc_get_gpr(vcpu, 5),
> + kvmppc_get_gpr(vcpu, 6));
> + break;
> default:
> return RESUME_HOST;
> }
> @@ -1127,6 +1165,7 @@ static int kvmppc_hcall_impl_hv(unsigned long cmd)
> case H_IPOLL:
> case H_XIRR_X:
> #endif
> + case H_PAGE_INIT:
> return 1;
> }
>
>
--
Alexey
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler
2019-03-19 4:04 [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler Suraj Jitindar Singh
2019-03-19 6:53 ` Alexey Kardashevskiy
@ 2019-03-22 5:04 ` Suraj Jitindar Singh
1 sibling, 0 replies; 3+ messages in thread
From: Suraj Jitindar Singh @ 2019-03-22 5:04 UTC (permalink / raw)
To: kvm-ppc
On Tue, 2019-03-19 at 17:53 +1100, Alexey Kardashevskiy wrote:
>
> On 19/03/2019 15:04, Suraj Jitindar Singh wrote:
> > Implement a virtual mode handler for the H_CALL H_PAGE_INIT which
> > can be
> > used to zero or copy a guest page. The page is defined to be 4k and
> > must
> > be 4k aligned.
> >
> > The in-kernel handler halves the time to handle this H_CALL
> > compared to
> > handling it in userspace for a radix guest.
> >
> > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
> > ---
> > arch/powerpc/kvm/book3s_hv.c | 39
> > +++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 39 insertions(+)
> >
> > diff --git a/arch/powerpc/kvm/book3s_hv.c
> > b/arch/powerpc/kvm/book3s_hv.c
> > index 7179ea783f4f..fa29cc4900c2 100644
> > --- a/arch/powerpc/kvm/book3s_hv.c
> > +++ b/arch/powerpc/kvm/book3s_hv.c
> > @@ -883,6 +883,39 @@ static int kvmppc_copy_guest(struct kvm *kvm,
> > gpa_t to, gpa_t from,
> > return 0;
> > }
> >
> > +static int kvmppc_h_page_init(struct kvm_vcpu *vcpu, unsigned long
> > flags,
>
>
>
> > + unsigned long dest, unsigned long
> > src)
> > +{
> > + int ret = H_FUNCTION;
> > + u64 pg_sz = 1UL << 12; /* 4K page size */
> > + u64 pg_mask = pg_sz - 1;
>
>
> Ditch pg_sz and just use SZ_4K? The page size is not going to change
> here ever.
Yep, will do. Didn't realise that was a thing
>
>
> > +
> > + /* Check for invalid flags (H_PAGE_SET_LOANED covers all
> > CMO flags) */
> > + if (flags & ~(H_ICACHE_INVALIDATE | H_ICACHE_SYNCHRONIZE |
> > + H_ZERO_PAGE | H_COPY_PAGE |
> > H_PAGE_SET_LOANED))
> > + return H_PARAMETER;
> > +
> > + /* dest (and src if copy_page flag set) must be page
> > aligned */
> > + if ((dest & pg_mask) || ((flags & H_COPY_PAGE) && (src &
> > pg_mask)))
> > + return H_PARAMETER;
> > +
> > + /* zero and/or copy the page as determined by the flags */
> > + if (flags & H_ZERO_PAGE) {
> > + ret = kvm_clear_guest(vcpu->kvm, dest, pg_sz);
> > + if (ret < 0)
> > + return H_PARAMETER;
> > + }
> > + if (flags & H_COPY_PAGE) {
>
>
> If H_COPY_PAGE is set, is there any good reason to do kvm_clear_guest
> first even if H_ZERO_PAGE is set? It should not happen in practice
> and
> it is no harm but also no sense.
True, if both are set then we can get away with only doing copy since
it will have the same effect.
>
> > + ret = kvmppc_copy_guest(vcpu->kvm, dest, src,
> > pg_sz);
> > + if (ret < 0)
> > + return H_PARAMETER;
> > + }
>
>
> else if (src)
> return H_PARAMETER;
I'm not sure that's technically an error so I'm going to leave it out.
>
>
>
> > +
> > + /* We can ignore the remaining flags */
> > +
> > + return H_SUCCESS;
> > +}
> > +
> > static int kvm_arch_vcpu_yield_to(struct kvm_vcpu *target)
> > {
> > struct kvmppc_vcore *vcore = target->arch.vcore;
> > @@ -1083,6 +1116,11 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu
> > *vcpu)
> > if (nesting_enabled(vcpu->kvm))
> > ret > > kvmhv_copy_tofrom_guest_nested(vcpu);
> > break;
> > + case H_PAGE_INIT:
> > + ret = kvmppc_h_page_init(vcpu,
> > kvmppc_get_gpr(vcpu, 4),
> > + kvmppc_get_gpr(vcpu, 5),
> > + kvmppc_get_gpr(vcpu, 6));
> > + break;
> > default:
> > return RESUME_HOST;
> > }
> > @@ -1127,6 +1165,7 @@ static int kvmppc_hcall_impl_hv(unsigned long
> > cmd)
> > case H_IPOLL:
> > case H_XIRR_X:
> > #endif
> > + case H_PAGE_INIT:
> > return 1;
> > }
> >
> >
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-03-22 5:04 UTC | newest]
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2019-03-19 4:04 [PATCH 2/3] KVM: PPC: Book3S HV: Implement virtual mode H_PAGE_INIT handler Suraj Jitindar Singh
2019-03-19 6:53 ` Alexey Kardashevskiy
2019-03-22 5:04 ` Suraj Jitindar Singh
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