[Qemu-devel] [PATCH v3 0/3] Add guest PMU in machine virt

[Qemu-devel] [PATCH v3 0/3] Add guest PMU in machine virt

[Shannon Zhao]

From: Shannon Zhao <shannon.zhao@linaro.org>

KVM-ARM64 supports guest PMU now. This series add the support in machine
virt so that guest could use PMU.

Changes since v2:
* address Andrew's comments on PATCH 2, thanks

Changes since v1:
* rebase on master
* Address Andrew's comments, add a macro PPI, fix code style, add
  cpu_to_le32()

Shannon Zhao (3):
  target-arm: kvm64: set guest PMUv3 feature bit if supported
  hw/arm/virt: Add PMU node for virt machine
  hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

 hw/arm/virt-acpi-build.c |  3 +++
 hw/arm/virt.c            | 34 ++++++++++++++++++++++++++++++++++
 include/hw/arm/virt.h    |  4 ++++
 include/sysemu/kvm.h     |  1 +
 stubs/kvm.c              |  5 +++++
 target-arm/cpu-qom.h     |  2 ++
 target-arm/kvm64.c       | 44 ++++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 93 insertions(+)

-- 
2.0.4

[Qemu-devel] [PATCH v3 1/3] target-arm: kvm64: set guest PMUv3 feature bit if supported

[Shannon Zhao]

From: Shannon Zhao <shannon.zhao@linaro.org>

Check if kvm supports guest PMUv3. If so, set the corresponding feature
bit for vcpu.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
---
 target-arm/cpu-qom.h | 2 ++
 target-arm/kvm64.c   | 5 +++++
 2 files changed, 7 insertions(+)

diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h
index 1061c08..93aa6a4 100644
--- a/target-arm/cpu-qom.h
+++ b/target-arm/cpu-qom.h
@@ -105,6 +105,8 @@ typedef struct ARMCPU {
     bool powered_off;
     /* CPU has security extension */
     bool has_el3;
+    /* CPU has PMU (Performance Monitor Unit) */
+    bool has_pmu;
 
     /* CPU has memory protection unit */
     bool has_mpu;
diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c
index e8527bf..b364789 100644
--- a/target-arm/kvm64.c
+++ b/target-arm/kvm64.c
@@ -461,6 +461,11 @@ int kvm_arch_init_vcpu(CPUState *cs)
     if (!arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
         cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_EL1_32BIT;
     }
+    if (kvm_irqchip_in_kernel() &&
+        kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_PMU_V3)) {
+        cpu->has_pmu = true;
+        cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_PMU_V3;
+    }
 
     /* Do KVM_ARM_VCPU_INIT ioctl */
     ret = kvm_arm_vcpu_init(cs);
-- 
2.0.4

[Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Shannon Zhao]

From: Shannon Zhao <shannon.zhao@linaro.org>

Add a virtual PMU device for virt machine while use PPI 7 for PMU
overflow interrupt number.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
---
 hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
 include/hw/arm/virt.h |  4 ++++
 include/sysemu/kvm.h  |  1 +
 stubs/kvm.c           |  5 +++++
 target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 83 insertions(+)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 56d35c7..c3632d8 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
     qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
 }
 
+static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
+{
+    CPUState *cpu;
+    ARMCPU *armcpu;
+    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
+
+    CPU_FOREACH(cpu) {
+        armcpu = ARM_CPU(cpu);
+        if (!armcpu->has_pmu) {
+            return;
+        }
+
+        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));
+    }
+
+    if (gictype == 2) {
+        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
+                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
+                             (1 << vbi->smp_cpus) - 1);
+    }
+
+    armcpu = ARM_CPU(qemu_get_cpu(0));
+    qemu_fdt_add_subnode(vbi->fdt, "/pmu");
+    if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) {
+        const char compat[] = "arm,armv8-pmuv3";
+        qemu_fdt_setprop(vbi->fdt, "/pmu", "compatible",
+                         compat, sizeof(compat));
+        qemu_fdt_setprop_cells(vbi->fdt, "/pmu", "interrupts",
+                               GIC_FDT_IRQ_TYPE_PPI, VIRTUAL_PMU_IRQ, irqflags);
+    }
+}
+
 static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic)
 {
     int i;
@@ -1246,6 +1278,8 @@ static void machvirt_init(MachineState *machine)
 
     create_gic(vbi, pic, gic_version, vms->secure);
 
+    fdt_add_pmu_nodes(vbi, gic_version);
+
     create_uart(vbi, pic, VIRT_UART, sysmem);
 
     if (vms->secure) {
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index ecd8589..b50f095 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -40,6 +40,10 @@
 #define ARCH_TIMER_NS_EL1_IRQ 14
 #define ARCH_TIMER_NS_EL2_IRQ 10
 
+#define VIRTUAL_PMU_IRQ 7
+
+#define PPI(irq) ((irq) + 16)
+
 enum {
     VIRT_FLASH,
     VIRT_MEM,
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 0e18f15..90c2c54 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -523,4 +523,5 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source);
  * Returns: 0 on success, or a negative errno on failure.
  */
 int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
+void kvm_arm_pmu_create(CPUState *cs, int irq);
 #endif
diff --git a/stubs/kvm.c b/stubs/kvm.c
index ddd6204..58a348a 100644
--- a/stubs/kvm.c
+++ b/stubs/kvm.c
@@ -6,3 +6,8 @@ int kvm_arch_irqchip_create(MachineState *ms, KVMState *s)
 {
     return 0;
 }
+
+void kvm_arm_pmu_create(CPUState *cs, int irq)
+{
+    return;
+}
diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c
index b364789..22fe2a3 100644
--- a/target-arm/kvm64.c
+++ b/target-arm/kvm64.c
@@ -382,6 +382,45 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr)
     return NULL;
 }
 
+static bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr)
+{
+    return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0;
+}
+
+void kvm_arm_pmu_create(CPUState *cs, int irq)
+{
+    int err;
+
+    struct kvm_device_attr attr = {
+        .group = KVM_ARM_VCPU_PMU_V3_CTRL,
+        .addr = (intptr_t)&irq,
+        .attr = KVM_ARM_VCPU_PMU_V3_IRQ,
+        .flags = 0,
+    };
+
+    if (!kvm_arm_pmu_support_ctrl(cs, &attr)) {
+        return;
+    }
+
+    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
+    if (err < 0) {
+        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
+                strerror(-err));
+        abort();
+    }
+
+    attr.group = KVM_ARM_VCPU_PMU_V3_CTRL;
+    attr.attr = KVM_ARM_VCPU_PMU_V3_INIT;
+    attr.addr = 0;
+    attr.flags = 0;
+
+    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
+    if (err < 0) {
+        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
+                strerror(-err));
+        abort();
+    }
+}
 
 static inline void set_feature(uint64_t *features, int feature)
 {
-- 
2.0.4

Re: [Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Andrew Jones]

On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@linaro.org>
> 
> Add a virtual PMU device for virt machine while use PPI 7 for PMU
> overflow interrupt number.
> 
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> ---
>  hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
>  include/hw/arm/virt.h |  4 ++++
>  include/sysemu/kvm.h  |  1 +
>  stubs/kvm.c           |  5 +++++
>  target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
>  5 files changed, 83 insertions(+)
> 
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 56d35c7..c3632d8 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
>      qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
>  }
>  
> +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
> +{
> +    CPUState *cpu;
> +    ARMCPU *armcpu;
> +    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
> +
> +    CPU_FOREACH(cpu) {
> +        armcpu = ARM_CPU(cpu);
> +        if (!armcpu->has_pmu) {
> +            return;
> +        }
> +
> +        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));

I think we need to return a failure code from kvm_arm_pmu_create, and
then do

           if (!kvm_arm_pmu_create(...)) {
               return;
           }

Otherwise we create a /pmu node for the guest that won't work.

> +    }
> +
> +    if (gictype == 2) {
> +        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
> +                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
> +                             (1 << vbi->smp_cpus) - 1);

So, if we're using gicv3, then we're level triggered and these cpu
mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good.

If we're using gicv2, then we're edge triggered and this mask is
defined. Assuming the GIC implementation requires using edge
triggered interrupts (as the comment in fdt_add_timer_nodes says),
then OK.

> +    }
> +
> +    armcpu = ARM_CPU(qemu_get_cpu(0));
> +    qemu_fdt_add_subnode(vbi->fdt, "/pmu");
> +    if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) {
> +        const char compat[] = "arm,armv8-pmuv3";
> +        qemu_fdt_setprop(vbi->fdt, "/pmu", "compatible",
> +                         compat, sizeof(compat));
> +        qemu_fdt_setprop_cells(vbi->fdt, "/pmu", "interrupts",
> +                               GIC_FDT_IRQ_TYPE_PPI, VIRTUAL_PMU_IRQ, irqflags);
> +    }
> +}
> +
>  static void create_v2m(VirtBoardInfo *vbi, qemu_irq *pic)
>  {
>      int i;
> @@ -1246,6 +1278,8 @@ static void machvirt_init(MachineState *machine)
>  
>      create_gic(vbi, pic, gic_version, vms->secure);
>  
> +    fdt_add_pmu_nodes(vbi, gic_version);
> +
>      create_uart(vbi, pic, VIRT_UART, sysmem);
>  
>      if (vms->secure) {
> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
> index ecd8589..b50f095 100644
> --- a/include/hw/arm/virt.h
> +++ b/include/hw/arm/virt.h
> @@ -40,6 +40,10 @@
>  #define ARCH_TIMER_NS_EL1_IRQ 14
>  #define ARCH_TIMER_NS_EL2_IRQ 10
>  
> +#define VIRTUAL_PMU_IRQ 7
> +
> +#define PPI(irq) ((irq) + 16)
> +
>  enum {
>      VIRT_FLASH,
>      VIRT_MEM,
> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
> index 0e18f15..90c2c54 100644
> --- a/include/sysemu/kvm.h
> +++ b/include/sysemu/kvm.h
> @@ -523,4 +523,5 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source);
>   * Returns: 0 on success, or a negative errno on failure.
>   */
>  int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
> +void kvm_arm_pmu_create(CPUState *cs, int irq);
>  #endif
> diff --git a/stubs/kvm.c b/stubs/kvm.c
> index ddd6204..58a348a 100644
> --- a/stubs/kvm.c
> +++ b/stubs/kvm.c
> @@ -6,3 +6,8 @@ int kvm_arch_irqchip_create(MachineState *ms, KVMState *s)
>  {
>      return 0;
>  }
> +
> +void kvm_arm_pmu_create(CPUState *cs, int irq)
> +{
> +    return;
> +}
> diff --git a/target-arm/kvm64.c b/target-arm/kvm64.c
> index b364789..22fe2a3 100644
> --- a/target-arm/kvm64.c
> +++ b/target-arm/kvm64.c
> @@ -382,6 +382,45 @@ static CPUWatchpoint *find_hw_watchpoint(CPUState *cpu, target_ulong addr)
>      return NULL;
>  }
>  
> +static bool kvm_arm_pmu_support_ctrl(CPUState *cs, struct kvm_device_attr *attr)
> +{
> +    return kvm_vcpu_ioctl(cs, KVM_HAS_DEVICE_ATTR, attr) == 0;
> +}
> +
> +void kvm_arm_pmu_create(CPUState *cs, int irq)
> +{
> +    int err;
> +
> +    struct kvm_device_attr attr = {
> +        .group = KVM_ARM_VCPU_PMU_V3_CTRL,
> +        .addr = (intptr_t)&irq,
> +        .attr = KVM_ARM_VCPU_PMU_V3_IRQ,
> +        .flags = 0,
> +    };
> +
> +    if (!kvm_arm_pmu_support_ctrl(cs, &attr)) {
> +        return;
> +    }
> +
> +    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
> +    if (err < 0) {
> +        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
> +                strerror(-err));
> +        abort();
> +    }
> +
> +    attr.group = KVM_ARM_VCPU_PMU_V3_CTRL;
> +    attr.attr = KVM_ARM_VCPU_PMU_V3_INIT;
> +    attr.addr = 0;
> +    attr.flags = 0;
> +
> +    err = kvm_vcpu_ioctl(cs, KVM_SET_DEVICE_ATTR, &attr);
> +    if (err < 0) {
> +        fprintf(stderr, "KVM_SET_DEVICE_ATTR failed: %s\n",
> +                strerror(-err));
> +        abort();
> +    }
> +}
>  
>  static inline void set_feature(uint64_t *features, int feature)
>  {
> -- 
> 2.0.4
> 
> 
>

Thanks,
drew 

Re: [Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Shannon Zhao]

On 2016/4/25 17:22, Andrew Jones wrote:
> On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote:
>> > From: Shannon Zhao <shannon.zhao@linaro.org>
>> > 
>> > Add a virtual PMU device for virt machine while use PPI 7 for PMU
>> > overflow interrupt number.
>> > 
>> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
>> > ---
>> >  hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
>> >  include/hw/arm/virt.h |  4 ++++
>> >  include/sysemu/kvm.h  |  1 +
>> >  stubs/kvm.c           |  5 +++++
>> >  target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
>> >  5 files changed, 83 insertions(+)
>> > 
>> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
>> > index 56d35c7..c3632d8 100644
>> > --- a/hw/arm/virt.c
>> > +++ b/hw/arm/virt.c
>> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
>> >      qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
>> >  }
>> >  
>> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
>> > +{
>> > +    CPUState *cpu;
>> > +    ARMCPU *armcpu;
>> > +    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
>> > +
>> > +    CPU_FOREACH(cpu) {
>> > +        armcpu = ARM_CPU(cpu);
>> > +        if (!armcpu->has_pmu) {
>> > +            return;
>> > +        }
>> > +
>> > +        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));
> I think we need to return a failure code from kvm_arm_pmu_create, and
> then do
> 
>            if (!kvm_arm_pmu_create(...)) {
>                return;
>            }
> 
> Otherwise we create a /pmu node for the guest that won't work.
> 
Ok, will update.

>> > +    }
>> > +
>> > +    if (gictype == 2) {
>> > +        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
>> > +                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
>> > +                             (1 << vbi->smp_cpus) - 1);
> So, if we're using gicv3, then we're level triggered and these cpu
> mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good.
> 
> If we're using gicv2, then we're edge triggered and this mask is
> defined. Assuming the GIC implementation requires using edge
> triggered interrupts (as the comment in fdt_add_timer_nodes says),
> then OK.
> 
IIRC the comments in fdt_add_timer_nodes are not correct now since KVM
makes PPI level triggered.

    /* Note that on A15 h/w these interrupts are level-triggered,
     * but for the GIC implementation provided by both QEMU and KVM
     * they are edge-triggered.
     */

Thanks,
-- 
Shannon

Re: [Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Andrew Jones]

On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote:
> 
> 
> On 2016/4/25 17:22, Andrew Jones wrote:
> > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote:
> >> > From: Shannon Zhao <shannon.zhao@linaro.org>
> >> > 
> >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU
> >> > overflow interrupt number.
> >> > 
> >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> >> > ---
> >> >  hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
> >> >  include/hw/arm/virt.h |  4 ++++
> >> >  include/sysemu/kvm.h  |  1 +
> >> >  stubs/kvm.c           |  5 +++++
> >> >  target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
> >> >  5 files changed, 83 insertions(+)
> >> > 
> >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> >> > index 56d35c7..c3632d8 100644
> >> > --- a/hw/arm/virt.c
> >> > +++ b/hw/arm/virt.c
> >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
> >> >      qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
> >> >  }
> >> >  
> >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
> >> > +{
> >> > +    CPUState *cpu;
> >> > +    ARMCPU *armcpu;
> >> > +    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
> >> > +
> >> > +    CPU_FOREACH(cpu) {
> >> > +        armcpu = ARM_CPU(cpu);
> >> > +        if (!armcpu->has_pmu) {
> >> > +            return;
> >> > +        }
> >> > +
> >> > +        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));
> > I think we need to return a failure code from kvm_arm_pmu_create, and
> > then do
> > 
> >            if (!kvm_arm_pmu_create(...)) {
> >                return;
> >            }
> > 
> > Otherwise we create a /pmu node for the guest that won't work.
> > 
> Ok, will update.
> 
> >> > +    }
> >> > +
> >> > +    if (gictype == 2) {
> >> > +        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
> >> > +                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
> >> > +                             (1 << vbi->smp_cpus) - 1);
> > So, if we're using gicv3, then we're level triggered and these cpu
> > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good.
> > 
> > If we're using gicv2, then we're edge triggered and this mask is
> > defined. Assuming the GIC implementation requires using edge
> > triggered interrupts (as the comment in fdt_add_timer_nodes says),
> > then OK.
> > 
> IIRC the comments in fdt_add_timer_nodes are not correct now since KVM
> makes PPI level triggered.
> 
>     /* Note that on A15 h/w these interrupts are level-triggered,
>      * but for the GIC implementation provided by both QEMU and KVM
>      * they are edge-triggered.
>      */

OK, in that case the comment should be updated to say something like
"used to", but I suspect it's too late for the timer to switch to
level at this point anyway, unless KVM can be probed to determine if
level is OK.

However, for PMU, we know that if the PMU feature exists, then level is
OK, so if we want a level triggered interrupt for PMU, then we should
change the giv2 irqflags assignment to an '|=' of the cpu mask.

Thanks,
drew

Re: [Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Shannon Zhao]

On 2016年04月25日 19:52, Andrew Jones wrote:
> On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote:
>> > 
>> > 
>> > On 2016/4/25 17:22, Andrew Jones wrote:
>>> > > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote:
>>>>> > >> > From: Shannon Zhao <shannon.zhao@linaro.org>
>>>>> > >> > 
>>>>> > >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU
>>>>> > >> > overflow interrupt number.
>>>>> > >> > 
>>>>> > >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
>>>>> > >> > ---
>>>>> > >> >  hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
>>>>> > >> >  include/hw/arm/virt.h |  4 ++++
>>>>> > >> >  include/sysemu/kvm.h  |  1 +
>>>>> > >> >  stubs/kvm.c           |  5 +++++
>>>>> > >> >  target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
>>>>> > >> >  5 files changed, 83 insertions(+)
>>>>> > >> > 
>>>>> > >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
>>>>> > >> > index 56d35c7..c3632d8 100644
>>>>> > >> > --- a/hw/arm/virt.c
>>>>> > >> > +++ b/hw/arm/virt.c
>>>>> > >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
>>>>> > >> >      qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
>>>>> > >> >  }
>>>>> > >> >  
>>>>> > >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
>>>>> > >> > +{
>>>>> > >> > +    CPUState *cpu;
>>>>> > >> > +    ARMCPU *armcpu;
>>>>> > >> > +    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
>>>>> > >> > +
>>>>> > >> > +    CPU_FOREACH(cpu) {
>>>>> > >> > +        armcpu = ARM_CPU(cpu);
>>>>> > >> > +        if (!armcpu->has_pmu) {
>>>>> > >> > +            return;
>>>>> > >> > +        }
>>>>> > >> > +
>>>>> > >> > +        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));
>>> > > I think we need to return a failure code from kvm_arm_pmu_create, and
>>> > > then do
>>> > > 
>>> > >            if (!kvm_arm_pmu_create(...)) {
>>> > >                return;
>>> > >            }
>>> > > 
>>> > > Otherwise we create a /pmu node for the guest that won't work.
>>> > > 
>> > Ok, will update.
>> > 
>>>>> > >> > +    }
>>>>> > >> > +
>>>>> > >> > +    if (gictype == 2) {
>>>>> > >> > +        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
>>>>> > >> > +                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
>>>>> > >> > +                             (1 << vbi->smp_cpus) - 1);
>>> > > So, if we're using gicv3, then we're level triggered and these cpu
>>> > > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good.
>>> > > 
>>> > > If we're using gicv2, then we're edge triggered and this mask is
>>> > > defined. Assuming the GIC implementation requires using edge
>>> > > triggered interrupts (as the comment in fdt_add_timer_nodes says),
>>> > > then OK.
>>> > > 
>> > IIRC the comments in fdt_add_timer_nodes are not correct now since KVM
>> > makes PPI level triggered.
>> > 
>> >     /* Note that on A15 h/w these interrupts are level-triggered,
>> >      * but for the GIC implementation provided by both QEMU and KVM
>> >      * they are edge-triggered.
>> >      */
> OK, in that case the comment should be updated to say something like
> "used to", but I suspect it's too late for the timer to switch to
> level at this point anyway, unless KVM can be probed to determine if
> level is OK.
> 
> However, for PMU, we know that if the PMU feature exists, then level is
> OK, so if we want a level triggered interrupt for PMU, then we should
> change the giv2 irqflags assignment to an '|=' of the cpu mask.
Since for gicv2, the maximum of vbi->smp_cpus is 8, so it will not
overflow and the result of deposit32 is right, I think.

Thanks,
-- 
Shannon

Re: [Qemu-devel] [PATCH v3 2/3] hw/arm/virt: Add PMU node for virt machine

[Andrew Jones]

On Mon, Apr 25, 2016 at 09:54:50PM +0800, Shannon Zhao wrote:
> On 2016年04月25日 19:52, Andrew Jones wrote:
> > On Mon, Apr 25, 2016 at 07:37:13PM +0800, Shannon Zhao wrote:
> >> > 
> >> > 
> >> > On 2016/4/25 17:22, Andrew Jones wrote:
> >>> > > On Mon, Apr 25, 2016 at 03:11:45PM +0800, Shannon Zhao wrote:
> >>>>> > >> > From: Shannon Zhao <shannon.zhao@linaro.org>
> >>>>> > >> > 
> >>>>> > >> > Add a virtual PMU device for virt machine while use PPI 7 for PMU
> >>>>> > >> > overflow interrupt number.
> >>>>> > >> > 
> >>>>> > >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> >>>>> > >> > ---
> >>>>> > >> >  hw/arm/virt.c         | 34 ++++++++++++++++++++++++++++++++++
> >>>>> > >> >  include/hw/arm/virt.h |  4 ++++
> >>>>> > >> >  include/sysemu/kvm.h  |  1 +
> >>>>> > >> >  stubs/kvm.c           |  5 +++++
> >>>>> > >> >  target-arm/kvm64.c    | 39 +++++++++++++++++++++++++++++++++++++++
> >>>>> > >> >  5 files changed, 83 insertions(+)
> >>>>> > >> > 
> >>>>> > >> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> >>>>> > >> > index 56d35c7..c3632d8 100644
> >>>>> > >> > --- a/hw/arm/virt.c
> >>>>> > >> > +++ b/hw/arm/virt.c
> >>>>> > >> > @@ -428,6 +428,38 @@ static void fdt_add_gic_node(VirtBoardInfo *vbi, int type)
> >>>>> > >> >      qemu_fdt_setprop_cell(vbi->fdt, "/intc", "phandle", vbi->gic_phandle);
> >>>>> > >> >  }
> >>>>> > >> >  
> >>>>> > >> > +static void fdt_add_pmu_nodes(const VirtBoardInfo *vbi, int gictype)
> >>>>> > >> > +{
> >>>>> > >> > +    CPUState *cpu;
> >>>>> > >> > +    ARMCPU *armcpu;
> >>>>> > >> > +    uint32_t irqflags = GIC_FDT_IRQ_FLAGS_LEVEL_HI;
> >>>>> > >> > +
> >>>>> > >> > +    CPU_FOREACH(cpu) {
> >>>>> > >> > +        armcpu = ARM_CPU(cpu);
> >>>>> > >> > +        if (!armcpu->has_pmu) {
> >>>>> > >> > +            return;
> >>>>> > >> > +        }
> >>>>> > >> > +
> >>>>> > >> > +        kvm_arm_pmu_create(cpu, PPI(VIRTUAL_PMU_IRQ));
> >>> > > I think we need to return a failure code from kvm_arm_pmu_create, and
> >>> > > then do
> >>> > > 
> >>> > >            if (!kvm_arm_pmu_create(...)) {
> >>> > >                return;
> >>> > >            }
> >>> > > 
> >>> > > Otherwise we create a /pmu node for the guest that won't work.
> >>> > > 
> >> > Ok, will update.
> >> > 
> >>>>> > >> > +    }
> >>>>> > >> > +
> >>>>> > >> > +    if (gictype == 2) {
> >>>>> > >> > +        irqflags = deposit32(irqflags, GIC_FDT_IRQ_PPI_CPU_START,
> >>>>> > >> > +                             GIC_FDT_IRQ_PPI_CPU_WIDTH,
> >>>>> > >> > +                             (1 << vbi->smp_cpus) - 1);
> >>> > > So, if we're using gicv3, then we're level triggered and these cpu
> >>> > > mask bits aren't defined by the arm,gic-v3.txt bindings spec. Good.
> >>> > > 
> >>> > > If we're using gicv2, then we're edge triggered and this mask is
> >>> > > defined. Assuming the GIC implementation requires using edge
> >>> > > triggered interrupts (as the comment in fdt_add_timer_nodes says),
> >>> > > then OK.
> >>> > > 
> >> > IIRC the comments in fdt_add_timer_nodes are not correct now since KVM
> >> > makes PPI level triggered.
> >> > 
> >> >     /* Note that on A15 h/w these interrupts are level-triggered,
> >> >      * but for the GIC implementation provided by both QEMU and KVM
> >> >      * they are edge-triggered.
> >> >      */
> > OK, in that case the comment should be updated to say something like
> > "used to", but I suspect it's too late for the timer to switch to
> > level at this point anyway, unless KVM can be probed to determine if
> > level is OK.
> > 
> > However, for PMU, we know that if the PMU feature exists, then level is
> > OK, so if we want a level triggered interrupt for PMU, then we should
> > change the giv2 irqflags assignment to an '|=' of the cpu mask.
> Since for gicv2, the maximum of vbi->smp_cpus is 8, so it will not
> overflow and the result of deposit32 is right, I think.

Yes. I was actually referring to the level flag, thinking it was getting
overwritten with zero, but now I see in deposit32's description that
"Bits of @value outside the bit field are not modified." So this is
fine.

Thanks,
drew

[Qemu-devel] [PATCH v3 3/3] hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

[Shannon Zhao]

From: Shannon Zhao <shannon.zhao@linaro.org>

Add PMU IRQ number in ACPI table, then we can use PMU in guest through
ACPI.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
---
 hw/arm/virt-acpi-build.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index f51fe39..5031232 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -491,6 +491,9 @@ build_madt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
         gicc->arm_mpidr = armcpu->mp_affinity;
         gicc->uid = i;
         gicc->flags = cpu_to_le32(ACPI_GICC_ENABLED);
+
+        if (armcpu->has_pmu)
+            gicc->performance_interrupt = cpu_to_le32(PPI(VIRTUAL_PMU_IRQ));
     }
 
     if (guest_info->gic_version == 3) {
-- 
2.0.4

Re: [Qemu-devel] [PATCH v3 3/3] hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

[Andrew Jones]

On Mon, Apr 25, 2016 at 03:11:46PM +0800, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@linaro.org>
> 
> Add PMU IRQ number in ACPI table, then we can use PMU in guest through
> ACPI.
> 
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> Reviewed-by: Andrew Jones <drjones@redhat.com>
> ---
>  hw/arm/virt-acpi-build.c | 3 +++
>  1 file changed, 3 insertions(+)

Question: for testing of this, did you use
https://lkml.org/lkml/2016/4/12/755 ?

Thanks,
drew

> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index f51fe39..5031232 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -491,6 +491,9 @@ build_madt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
>          gicc->arm_mpidr = armcpu->mp_affinity;
>          gicc->uid = i;
>          gicc->flags = cpu_to_le32(ACPI_GICC_ENABLED);
> +
> +        if (armcpu->has_pmu)
> +            gicc->performance_interrupt = cpu_to_le32(PPI(VIRTUAL_PMU_IRQ));
>      }
>  
>      if (guest_info->gic_version == 3) {
> -- 
> 2.0.4
> 
> 
> 

Re: [Qemu-devel] [PATCH v3 3/3] hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

[Shannon Zhao]

On 2016年04月25日 20:42, Andrew Jones wrote:
> On Mon, Apr 25, 2016 at 03:11:46PM +0800, Shannon Zhao wrote:
>> > From: Shannon Zhao <shannon.zhao@linaro.org>
>> > 
>> > Add PMU IRQ number in ACPI table, then we can use PMU in guest through
>> > ACPI.
>> > 
>> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
>> > Reviewed-by: Andrew Jones <drjones@redhat.com>
>> > ---
>> >  hw/arm/virt-acpi-build.c | 3 +++
>> >  1 file changed, 3 insertions(+)
> Question: for testing of this, did you use
> https://lkml.org/lkml/2016/4/12/755 ?
Actually I didn't test PMU with ACPI since I didn't notice the patch
series you point out and it's very obvious for QEMU changes(adding irq
flag and irq number in GICC). I will have a test later.

Thanks,
-- 
Shannon

Re: [Qemu-devel] [PATCH v3 3/3] hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

[Shannon Zhao]

On 2016/4/25 21:49, Shannon Zhao wrote:
> On 2016年04月25日 20:42, Andrew Jones wrote:
>> > On Mon, Apr 25, 2016 at 03:11:46PM +0800, Shannon Zhao wrote:
>>>> >> > From: Shannon Zhao <shannon.zhao@linaro.org>
>>>> >> > 
>>>> >> > Add PMU IRQ number in ACPI table, then we can use PMU in guest through
>>>> >> > ACPI.
>>>> >> > 
>>>> >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
>>>> >> > Reviewed-by: Andrew Jones <drjones@redhat.com>
>>>> >> > ---
>>>> >> >  hw/arm/virt-acpi-build.c | 3 +++
>>>> >> >  1 file changed, 3 insertions(+)
>> > Question: for testing of this, did you use
>> > https://lkml.org/lkml/2016/4/12/755 ?
> Actually I didn't test PMU with ACPI since I didn't notice the patch
> series you point out and it's very obvious for QEMU changes(adding irq
> flag and irq number in GICC). I will have a test later.

I have test this patch series using ACPI and guest with the patches you
point out. Guest prints below logs and perf works well in guest.

[    0.000000] ACPI-PMU: Assign CPU 0 girq 23 level 0
[    0.000000] ACPI-PMU: Assign CPU 1 girq 23 level 0
[    0.000000] ACPI-PMU: Assign CPU 2 girq 23 level 0
[    0.000000] ACPI-PMU: Assign CPU 3 girq 23 level 0
[...]
[    0.094782] ACPI-PMU: Setting up 4 PMUs for CPU type D07

Thanks,
-- 
Shannon

Re: [Qemu-devel] [PATCH v3 3/3] hw/arm/virt-acpi-build: Add PMU IRQ number in ACPI table

[Andrew Jones]

On Tue, Apr 26, 2016 at 07:08:25PM +0800, Shannon Zhao wrote:
> 
> 
> On 2016/4/25 21:49, Shannon Zhao wrote:
> > On 2016年04月25日 20:42, Andrew Jones wrote:
> >> > On Mon, Apr 25, 2016 at 03:11:46PM +0800, Shannon Zhao wrote:
> >>>> >> > From: Shannon Zhao <shannon.zhao@linaro.org>
> >>>> >> > 
> >>>> >> > Add PMU IRQ number in ACPI table, then we can use PMU in guest through
> >>>> >> > ACPI.
> >>>> >> > 
> >>>> >> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> >>>> >> > Reviewed-by: Andrew Jones <drjones@redhat.com>
> >>>> >> > ---
> >>>> >> >  hw/arm/virt-acpi-build.c | 3 +++
> >>>> >> >  1 file changed, 3 insertions(+)
> >> > Question: for testing of this, did you use
> >> > https://lkml.org/lkml/2016/4/12/755 ?
> > Actually I didn't test PMU with ACPI since I didn't notice the patch
> > series you point out and it's very obvious for QEMU changes(adding irq
> > flag and irq number in GICC). I will have a test later.
> 
> I have test this patch series using ACPI and guest with the patches you
> point out. Guest prints below logs and perf works well in guest.
> 
> [    0.000000] ACPI-PMU: Assign CPU 0 girq 23 level 0
> [    0.000000] ACPI-PMU: Assign CPU 1 girq 23 level 0
> [    0.000000] ACPI-PMU: Assign CPU 2 girq 23 level 0
> [    0.000000] ACPI-PMU: Assign CPU 3 girq 23 level 0
> [...]
> [    0.094782] ACPI-PMU: Setting up 4 PMUs for CPU type D07

Thanks for the additional testing Shannon!

drew