[PATCH for 7.2 0/2] s390x/s390-virtio-ccw:

[PATCH for 7.2 0/2] s390x/s390-virtio-ccw:

[Cédric Le Goater]

From: Cédric Le Goater <clg@redhat.com>

Hello,

This series removes the redundant "zpcii-disable" machine property and
and introduces a GlobalProperty compat array to maintain the same
behaviour on older machines.

Thanks,

C.

Cédric Le Goater (2):
  Revert "s390x/s390-virtio-ccw: add zpcii-disable machine property"
  s390x/s390-virtio-ccw: Switch off zPCI enhancements on older machines

 include/hw/s390x/s390-virtio-ccw.h |  1 -
 hw/s390x/s390-pci-kvm.c            |  4 +---
 hw/s390x/s390-virtio-ccw.c         | 29 +++++------------------------
 util/qemu-config.c                 |  4 ----
 qemu-options.hx                    |  8 +-------
 5 files changed, 7 insertions(+), 39 deletions(-)

-- 
2.38.1

[PATCH for 7.2 1/2] Revert "s390x/s390-virtio-ccw: add zpcii-disable machine property"

[Cédric Le Goater]

From: Cédric Le Goater <clg@redhat.com>

This reverts commit 59d1ce44396e3ad2330dc3261ff3da7ad3a16184.

The "zpcii-disable" machine property is redundant with the "interpret"
zPCI device property. Remove it for clarification.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 include/hw/s390x/s390-virtio-ccw.h |  1 -
 hw/s390x/s390-pci-kvm.c            |  4 +---
 hw/s390x/s390-virtio-ccw.c         | 24 ------------------------
 util/qemu-config.c                 |  4 ----
 qemu-options.hx                    |  8 +-------
 5 files changed, 2 insertions(+), 39 deletions(-)

diff --git a/include/hw/s390x/s390-virtio-ccw.h b/include/hw/s390x/s390-virtio-ccw.h
index 4f8a39abda..9bba21a916 100644
--- a/include/hw/s390x/s390-virtio-ccw.h
+++ b/include/hw/s390x/s390-virtio-ccw.h
@@ -27,7 +27,6 @@ struct S390CcwMachineState {
     bool aes_key_wrap;
     bool dea_key_wrap;
     bool pv;
-    bool zpcii_disable;
     uint8_t loadparm[8];
 };
 
diff --git a/hw/s390x/s390-pci-kvm.c b/hw/s390x/s390-pci-kvm.c
index 5eb7fd12e2..9134fe185f 100644
--- a/hw/s390x/s390-pci-kvm.c
+++ b/hw/s390x/s390-pci-kvm.c
@@ -22,9 +22,7 @@
 
 bool s390_pci_kvm_interp_allowed(void)
 {
-    return (kvm_s390_get_zpci_op() && !s390_is_pv() &&
-            !object_property_get_bool(OBJECT(qdev_get_machine()),
-                                      "zpcii-disable", NULL));
+    return kvm_s390_get_zpci_op() && !s390_is_pv();
 }
 
 int s390_pci_kvm_aif_enable(S390PCIBusDevice *pbdev, ZpciFib *fib, bool assist)
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 560ddbb6fb..bb98d40792 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -627,21 +627,6 @@ static inline void machine_set_dea_key_wrap(Object *obj, bool value,
     ms->dea_key_wrap = value;
 }
 
-static inline bool machine_get_zpcii_disable(Object *obj, Error **errp)
-{
-    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
-
-    return ms->zpcii_disable;
-}
-
-static inline void machine_set_zpcii_disable(Object *obj, bool value,
-                                             Error **errp)
-{
-    S390CcwMachineState *ms = S390_CCW_MACHINE(obj);
-
-    ms->zpcii_disable = value;
-}
-
 static S390CcwMachineClass *current_mc;
 
 /*
@@ -778,12 +763,6 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
             "Up to 8 chars in set of [A-Za-z0-9. ] (lower case chars converted"
             " to upper case) to pass to machine loader, boot manager,"
             " and guest kernel");
-
-    object_class_property_add_bool(oc, "zpcii-disable",
-                                   machine_get_zpcii_disable,
-                                   machine_set_zpcii_disable);
-    object_class_property_set_description(oc, "zpcii-disable",
-            "disable zPCI interpretation facilties");
 }
 
 static inline void s390_machine_initfn(Object *obj)
@@ -792,7 +771,6 @@ static inline void s390_machine_initfn(Object *obj)
 
     ms->aes_key_wrap = true;
     ms->dea_key_wrap = true;
-    ms->zpcii_disable = false;
 }
 
 static const TypeInfo ccw_machine_info = {
@@ -857,12 +835,10 @@ DEFINE_CCW_MACHINE(7_2, "7.2", true);
 static void ccw_machine_7_1_instance_options(MachineState *machine)
 {
     static const S390FeatInit qemu_cpu_feat = { S390_FEAT_LIST_QEMU_V7_1 };
-    S390CcwMachineState *ms = S390_CCW_MACHINE(machine);
 
     ccw_machine_7_2_instance_options(machine);
     s390_cpudef_featoff_greater(16, 1, S390_FEAT_PAIE);
     s390_set_qemu_cpu_model(0x8561, 15, 1, qemu_cpu_feat);
-    ms->zpcii_disable = true;
 }
 
 static void ccw_machine_7_1_class_options(MachineClass *mc)
diff --git a/util/qemu-config.c b/util/qemu-config.c
index 5325f6bf80..433488aa56 100644
--- a/util/qemu-config.c
+++ b/util/qemu-config.c
@@ -236,10 +236,6 @@ static QemuOptsList machine_opts = {
             .help = "Up to 8 chars in set of [A-Za-z0-9. ](lower case chars"
                     " converted to upper case) to pass to machine"
                     " loader, boot manager, and guest kernel",
-        },{
-            .name = "zpcii-disable",
-            .type = QEMU_OPT_BOOL,
-            .help = "disable zPCI interpretation facilities",
         },
         { /* End of list */ }
     }
diff --git a/qemu-options.hx b/qemu-options.hx
index 911d82afa5..1e140e99e1 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -37,8 +37,7 @@ DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
     "                memory-encryption=@var{} memory encryption object to use (default=none)\n"
     "                hmat=on|off controls ACPI HMAT support (default=off)\n"
     "                memory-backend='backend-id' specifies explicitly provided backend for main RAM (default=none)\n"
-    "                cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n"
-    "                zpcii-disable=on|off disables zPCI interpretation facilities (default=off)\n",
+    "                cxl-fmw.0.targets.0=firsttarget,cxl-fmw.0.targets.1=secondtarget,cxl-fmw.0.size=size[,cxl-fmw.0.interleave-granularity=granularity]\n",
     QEMU_ARCH_ALL)
 SRST
 ``-machine [type=]name[,prop=value[,...]]``
@@ -158,11 +157,6 @@ SRST
         ::
 
             -machine cxl-fmw.0.targets.0=cxl.0,cxl-fmw.0.targets.1=cxl.1,cxl-fmw.0.size=128G,cxl-fmw.0.interleave-granularity=512k
-
-    ``zpcii-disable=on|off``
-        Disables zPCI interpretation facilties on s390-ccw hosts.
-        This feature can be used to disable hardware virtual assists
-        related to zPCI devices. The default is off.
 ERST
 
 DEF("M", HAS_ARG, QEMU_OPTION_M,
-- 
2.38.1

[PATCH for 7.2 2/2] s390x/s390-virtio-ccw: Switch off zPCI enhancements on older machines

[Cédric Le Goater]

From: Cédric Le Goater <clg@redhat.com>

zPCI enhancement features (interpretation and forward assist) were
recently introduced to improve performance on PCI passthrough devices.
To maintain the same behaviour on older Z machines, deactivate the
features with the associated properties.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 hw/s390x/s390-virtio-ccw.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index bb98d40792..7d80bc1837 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -844,9 +844,14 @@ static void ccw_machine_7_1_instance_options(MachineState *machine)
 static void ccw_machine_7_1_class_options(MachineClass *mc)
 {
     S390CcwMachineClass *s390mc = S390_CCW_MACHINE_CLASS(mc);
+    static GlobalProperty compat[] = {
+        { TYPE_S390_PCI_DEVICE, "interpret", "off", },
+        { TYPE_S390_PCI_DEVICE, "forwarding-assist", "off", },
+    };
 
     ccw_machine_7_2_class_options(mc);
     compat_props_add(mc->compat_props, hw_compat_7_1, hw_compat_7_1_len);
+    compat_props_add(mc->compat_props, compat, G_N_ELEMENTS(compat));
     s390mc->max_threads = S390_MAX_CPUS;
 }
 DEFINE_CCW_MACHINE(7_1, "7.1", false);
-- 
2.38.1

Re: [PATCH for 7.2 0/2] s390x/s390-virtio-ccw:

[Matthew Rosato]

On 11/7/22 11:13 AM, Cédric Le Goater wrote:
> From: Cédric Le Goater <clg@redhat.com>
> 
> Hello,
> 
> This series removes the redundant "zpcii-disable" machine property and
> and introduces a GlobalProperty compat array to maintain the same
> behaviour on older machines.
> 
> Thanks,
> 
> C.

Thanks Cedric.

For the series:
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>

Also did a quick test on top of
https://gitlab.com/thuth/qemu.git tags/pull-request-2022-11-06

to verify that zPCI interpretation/forwarding is available as expected with machine 7.2 and off by default in 7.1 and older.

> 
> Cédric Le Goater (2):
>   Revert "s390x/s390-virtio-ccw: add zpcii-disable machine property"
>   s390x/s390-virtio-ccw: Switch off zPCI enhancements on older machines
> 
>  include/hw/s390x/s390-virtio-ccw.h |  1 -
>  hw/s390x/s390-pci-kvm.c            |  4 +---
>  hw/s390x/s390-virtio-ccw.c         | 29 +++++------------------------
>  util/qemu-config.c                 |  4 ----
>  qemu-options.hx                    |  8 +-------
>  5 files changed, 7 insertions(+), 39 deletions(-)
>