Re: [PATCH v14 06/11] s390x/cpu topology: interception of PTF instruction
On 1/16/23 19:24, Nina Schoetterl-Glausch wrote:
On Thu, 2023-01-05 at 15:53 +0100, Pierre Morel wrote:
When the host supports the CPU topology facility, the PTF
instruction with function code 2 is interpreted by the SIE,
provided that the userland hypervizor activates the interpretation
by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
The PTF instructions with function code 0 and 1 are intercepted
and must be emulated by the userland hypervizor.
During RESET all CPU of the configuration are placed in
horizontal polarity.
Signed-off-by: Pierre Morel
---
include/hw/s390x/cpu-topology.h| 3 +
include/hw/s390x/s390-virtio-ccw.h | 6 ++
target/s390x/cpu.h | 1 +
hw/s390x/cpu-topology.c| 92 ++
target/s390x/cpu-sysemu.c | 16 ++
target/s390x/kvm/kvm.c | 11
6 files changed, 129 insertions(+)
diff --git a/include/hw/s390x/cpu-topology.h b/include/hw/s390x/cpu-topology.h
index 9571aa70e5..33e23d78b9 100644
--- a/include/hw/s390x/cpu-topology.h
+++ b/include/hw/s390x/cpu-topology.h
@@ -55,11 +55,13 @@ typedef struct S390Topology {
QTAILQ_HEAD(, S390TopologyEntry) list;
uint8_t *sockets;
CpuTopology *smp;
+int polarity;
} S390Topology;
#ifdef CONFIG_KVM
bool s390_has_topology(void);
void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp);
+void s390_topology_set_polarity(int polarity);
#else
static inline bool s390_has_topology(void)
{
@@ -68,6 +70,7 @@ static inline bool s390_has_topology(void)
static inline void s390_topology_set_cpu(MachineState *ms,
S390CPU *cpu,
Error **errp) {}
+static inline void s390_topology_set_polarity(int polarity) {}
#endif
extern S390Topology s390_topology;
diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
index 9bba21a916..c1d46e78af 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -30,6 +30,12 @@ struct S390CcwMachineState {
uint8_t loadparm[8];
};
+#define S390_PTF_REASON_NONE (0x00 << 8)
+#define S390_PTF_REASON_DONE (0x01 << 8)
+#define S390_PTF_REASON_BUSY (0x02 << 8)
+#define S390_TOPO_FC_MASK 0xffUL
+void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra);
+
struct S390CcwMachineClass {
/*< private >*/
MachineClass parent_class;
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 01ade07009..5da4041576 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -864,6 +864,7 @@ void s390_do_cpu_set_diag318(CPUState *cs, run_on_cpu_data
arg);
int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
int vq, bool assign);
void s390_cpu_topology_reset(void);
+void s390_cpu_topology_set(void);
I don't like this name much, it's nondescript.
s390_cpu_topology_set_modified ?
#ifndef CONFIG_USER_ONLY
unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu);
#else
diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
index 438055c612..e6b4692581 100644
--- a/hw/s390x/cpu-topology.c
+++ b/hw/s390x/cpu-topology.c
@@ -97,6 +97,98 @@ static s390_topology_id s390_topology_from_cpu(S390CPU *cpu)
}
/**
+ * s390_topology_set_polarity
+ * @polarity: horizontal or vertical
+ *
+ * Changes the polarity of all the CPU in the configuration.
+ *
+ * If the dedicated CPU modifier attribute is set a vertical
+ * polarization is always high (Architecture).
+ * Otherwise we decide to set it as medium.
+ *
+ * Once done, advertise a topology change.
+ */
+void s390_topology_set_polarity(int polarity)
I don't like that this function ignores what kind of vertical polarization is
passed,
it's confusing.
That seems like a further reason to split horizontal/vertical from the
entitlement.
Yes.
I will also make the ordering of the TLE at the last moment instead of
doing it during hotplug or QAPI command.
This is something Cedric proposed some time ago and I think it is right,
it will be easier to do it once in STSI than on every change of topology,
hotplug, QAPI and polarization change with PTF.
Regards,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
Re: [PATCH v14 06/11] s390x/cpu topology: interception of PTF instruction
On 1/16/23 19:24, Nina Schoetterl-Glausch wrote:
On Thu, 2023-01-05 at 15:53 +0100, Pierre Morel wrote:
When the host supports the CPU topology facility, the PTF
instruction with function code 2 is interpreted by the SIE,
provided that the userland hypervizor activates the interpretation
by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
The PTF instructions with function code 0 and 1 are intercepted
and must be emulated by the userland hypervizor.
During RESET all CPU of the configuration are placed in
horizontal polarity.
Signed-off-by: Pierre Morel
---
include/hw/s390x/cpu-topology.h| 3 +
include/hw/s390x/s390-virtio-ccw.h | 6 ++
target/s390x/cpu.h | 1 +
hw/s390x/cpu-topology.c| 92 ++
target/s390x/cpu-sysemu.c | 16 ++
target/s390x/kvm/kvm.c | 11
6 files changed, 129 insertions(+)
diff --git a/include/hw/s390x/cpu-topology.h b/include/hw/s390x/cpu-topology.h
index 9571aa70e5..33e23d78b9 100644
--- a/include/hw/s390x/cpu-topology.h
+++ b/include/hw/s390x/cpu-topology.h
@@ -55,11 +55,13 @@ typedef struct S390Topology {
QTAILQ_HEAD(, S390TopologyEntry) list;
uint8_t *sockets;
CpuTopology *smp;
+int polarity;
} S390Topology;
#ifdef CONFIG_KVM
bool s390_has_topology(void);
void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp);
+void s390_topology_set_polarity(int polarity);
#else
static inline bool s390_has_topology(void)
{
@@ -68,6 +70,7 @@ static inline bool s390_has_topology(void)
static inline void s390_topology_set_cpu(MachineState *ms,
S390CPU *cpu,
Error **errp) {}
+static inline void s390_topology_set_polarity(int polarity) {}
#endif
extern S390Topology s390_topology;
diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
index 9bba21a916..c1d46e78af 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -30,6 +30,12 @@ struct S390CcwMachineState {
uint8_t loadparm[8];
};
+#define S390_PTF_REASON_NONE (0x00 << 8)
+#define S390_PTF_REASON_DONE (0x01 << 8)
+#define S390_PTF_REASON_BUSY (0x02 << 8)
+#define S390_TOPO_FC_MASK 0xffUL
+void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra);
+
struct S390CcwMachineClass {
/*< private >*/
MachineClass parent_class;
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 01ade07009..5da4041576 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -864,6 +864,7 @@ void s390_do_cpu_set_diag318(CPUState *cs, run_on_cpu_data
arg);
int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
int vq, bool assign);
void s390_cpu_topology_reset(void);
+void s390_cpu_topology_set(void);
I don't like this name much, it's nondescript.
s390_cpu_topology_set_modified ?
yes, better.
#ifndef CONFIG_USER_ONLY
unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu);
#else
diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
index 438055c612..e6b4692581 100644
--- a/hw/s390x/cpu-topology.c
+++ b/hw/s390x/cpu-topology.c
@@ -97,6 +97,98 @@ static s390_topology_id s390_topology_from_cpu(S390CPU *cpu)
}
/**
+ * s390_topology_set_polarity
+ * @polarity: horizontal or vertical
+ *
+ * Changes the polarity of all the CPU in the configuration.
+ *
+ * If the dedicated CPU modifier attribute is set a vertical
+ * polarization is always high (Architecture).
+ * Otherwise we decide to set it as medium.
+ *
+ * Once done, advertise a topology change.
+ */
+void s390_topology_set_polarity(int polarity)
I don't like that this function ignores what kind of vertical polarization is
passed,
it's confusing.
That seems like a further reason to split horizontal/vertical from the
entitlement.
OK, you are right.
I remove this function and put the s390_cpu_topology_set() inside the
handle_ptf()
+{
+S390TopologyEntry *entry;
I also expected this function to set s390_topology.polarization, but it doesn't.
+
+QTAILQ_FOREACH(entry, _topology.list, next) {
+if (polarity == S390_TOPOLOGY_POLARITY_HORIZONTAL) {
+entry->id.p = polarity;
+} else {
+if (entry->id.d) {
+entry->id.p = S390_TOPOLOGY_POLARITY_VERTICAL_HIGH;
+} else {
+entry->id.p = S390_TOPOLOGY_POLARITY_VERTICAL_MEDIUM;
+}
+}
+}
+s390_cpu_topology_set();
+}
+
+/*
+ * s390_handle_ptf:
+ *
+ * @register 1: contains the function code
+ *
+ * Function codes 0 and 1 handle the CPU polarization.
+ * We assume an horizontal topology, the only one supported currently
+ * by Linux, consequently we answer to function code 0, requesting
+ * horizontal polarization that it is already the current polarization
+ * and reject vertical polarization request
Re: [PATCH v14 06/11] s390x/cpu topology: interception of PTF instruction
On Thu, 2023-01-05 at 15:53 +0100, Pierre Morel wrote:
> When the host supports the CPU topology facility, the PTF
> instruction with function code 2 is interpreted by the SIE,
> provided that the userland hypervizor activates the interpretation
> by using the KVM_CAP_S390_CPU_TOPOLOGY KVM extension.
>
> The PTF instructions with function code 0 and 1 are intercepted
> and must be emulated by the userland hypervizor.
>
> During RESET all CPU of the configuration are placed in
> horizontal polarity.
>
> Signed-off-by: Pierre Morel
> ---
> include/hw/s390x/cpu-topology.h| 3 +
> include/hw/s390x/s390-virtio-ccw.h | 6 ++
> target/s390x/cpu.h | 1 +
> hw/s390x/cpu-topology.c| 92 ++
> target/s390x/cpu-sysemu.c | 16 ++
> target/s390x/kvm/kvm.c | 11
> 6 files changed, 129 insertions(+)
>
> diff --git a/include/hw/s390x/cpu-topology.h b/include/hw/s390x/cpu-topology.h
> index 9571aa70e5..33e23d78b9 100644
> --- a/include/hw/s390x/cpu-topology.h
> +++ b/include/hw/s390x/cpu-topology.h
> @@ -55,11 +55,13 @@ typedef struct S390Topology {
> QTAILQ_HEAD(, S390TopologyEntry) list;
> uint8_t *sockets;
> CpuTopology *smp;
> +int polarity;
> } S390Topology;
>
> #ifdef CONFIG_KVM
> bool s390_has_topology(void);
> void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp);
> +void s390_topology_set_polarity(int polarity);
> #else
> static inline bool s390_has_topology(void)
> {
> @@ -68,6 +70,7 @@ static inline bool s390_has_topology(void)
> static inline void s390_topology_set_cpu(MachineState *ms,
> S390CPU *cpu,
> Error **errp) {}
> +static inline void s390_topology_set_polarity(int polarity) {}
> #endif
> extern S390Topology s390_topology;
>
> diff --git a/include/hw/s390x/s390-virtio-ccw.h
> b/include/hw/s390x/s390-virtio-ccw.h
> index 9bba21a916..c1d46e78af 100644
> --- a/include/hw/s390x/s390-virtio-ccw.h
> +++ b/include/hw/s390x/s390-virtio-ccw.h
> @@ -30,6 +30,12 @@ struct S390CcwMachineState {
> uint8_t loadparm[8];
> };
>
> +#define S390_PTF_REASON_NONE (0x00 << 8)
> +#define S390_PTF_REASON_DONE (0x01 << 8)
> +#define S390_PTF_REASON_BUSY (0x02 << 8)
> +#define S390_TOPO_FC_MASK 0xffUL
> +void s390_handle_ptf(S390CPU *cpu, uint8_t r1, uintptr_t ra);
> +
> struct S390CcwMachineClass {
> /*< private >*/
> MachineClass parent_class;
> diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
> index 01ade07009..5da4041576 100644
> --- a/target/s390x/cpu.h
> +++ b/target/s390x/cpu.h
> @@ -864,6 +864,7 @@ void s390_do_cpu_set_diag318(CPUState *cs,
> run_on_cpu_data arg);
> int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
> int vq, bool assign);
> void s390_cpu_topology_reset(void);
> +void s390_cpu_topology_set(void);
I don't like this name much, it's nondescript.
s390_cpu_topology_set_modified ?
> #ifndef CONFIG_USER_ONLY
> unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu);
> #else
> diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c
> index 438055c612..e6b4692581 100644
> --- a/hw/s390x/cpu-topology.c
> +++ b/hw/s390x/cpu-topology.c
> @@ -97,6 +97,98 @@ static s390_topology_id s390_topology_from_cpu(S390CPU
> *cpu)
> }
>
> /**
> + * s390_topology_set_polarity
> + * @polarity: horizontal or vertical
> + *
> + * Changes the polarity of all the CPU in the configuration.
> + *
> + * If the dedicated CPU modifier attribute is set a vertical
> + * polarization is always high (Architecture).
> + * Otherwise we decide to set it as medium.
> + *
> + * Once done, advertise a topology change.
> + */
> +void s390_topology_set_polarity(int polarity)
I don't like that this function ignores what kind of vertical polarization is
passed,
it's confusing.
That seems like a further reason to split horizontal/vertical from the
entitlement.
> +{
> +S390TopologyEntry *entry;
I also expected this function to set s390_topology.polarization, but it doesn't.
> +
> +QTAILQ_FOREACH(entry, _topology.list, next) {
> +if (polarity == S390_TOPOLOGY_POLARITY_HORIZONTAL) {
> +entry->id.p = polarity;
> +} else {
> +if (entry->id.d) {
> +entry->id.p = S390_TOPOLOGY_POLARITY_VERTICAL_HIGH;
> +} else {
> +entry->id.p = S390_TOPOLOGY_POLARITY_VERTICAL_MEDIUM;
> +}
> +}
> +}
> +s390_cpu_topology_set();
> +}
> +
> +/*
> + * s390_handle_ptf:
> + *
> + * @register 1: contains the function code
> + *
> + * Function codes 0 and 1 handle the CPU polarization.
> + * We assume an horizontal topology, the only one supported currently
> + * by Linux, consequently we answer to function code 0, requesting
> + * horizontal polarization that it is already the current polarization
> + * and reject vertical
