[Qemu-devel] [PATCH for 2.11 0/5] TCG/ARM fixes for 2.11

[Qemu-devel] [PATCH for 2.11 0/5] TCG/ARM fixes for 2.11

[Emilio G. Cota]

Some MachineClass changes to fix TCG initialization of some
ARM boards for 2.11. This was originally reported by Thomas Huth in [1],
where Peter suggested a way to fix it. Further discussion in
another thread [2] followed up on this.

As a result of that follow-up discussion we also got some Zynq changes from
Alistair [3], which I'm including here since in order to test them
we need the first patch in this series.

Thanks,

		Emilio

[1] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg00078.html
[2] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg00502.html
[3] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg01842.html

Alistair Francis (2):
  xlnx-zynqmp: Properly support the smp command line option
  xlnx-zcu102: Add an info message deprecating the EP108

Emilio G. Cota (3):
  qom: move CPUClass.tcg_initialize to a global
  xlnx-zcu102: Specify the max number of CPUs for the EP108
  hw: add .min_cpus and .default_cpus fields to machine_class

 qemu-doc.texi           |  7 +++++++
 include/hw/boards.h     |  5 +++++
 include/qom/cpu.h       |  1 -
 exec.c                  |  5 +++--
 hw/arm/exynos4_boards.c | 12 ++++--------
 hw/arm/raspi.c          |  2 ++
 hw/arm/xlnx-zcu102.c    |  9 ++++++++-
 hw/arm/xlnx-zynqmp.c    | 26 ++++++++++++++++----------
 vl.c                    | 21 ++++++++++++++++++---
 9 files changed, 63 insertions(+), 25 deletions(-)

-- 
2.7.4

[Qemu-devel] [PATCH for 2.11 1/5] qom: move CPUClass.tcg_initialize to a global

[Emilio G. Cota]

55c3cee ("qom: Introduce CPUClass.tcg_initialize", 2017-10-24)
introduces a per-CPUClass bool that we check so that the target CPU
is initialized for TCG only once. This works well except when
we end up creating more than one CPUClass, in which case we end
up incorrectly initializing TCG more than once, i.e. once for
each CPUClass.

This can be replicated with:
  $ aarch64-softmmu/qemu-system-aarch64 -machine xlnx-zcu102 -smp 6 \
      -global driver=xlnx,,zynqmp,property=has_rpu,value=on
In this case the class name of the "RPUs" is prefixed by "cortex-r5-",
whereas the "regular" CPUs are prefixed by "cortex-a53-". This
results in two CPUClass instances being created.

Fix it by introducing a static variable, so that only the first
target CPU being initialized will initialize the target-dependent
part of TCG, regardless of CPUClass instances.

Fixes: 55c3ceef61fcf06fc98ddc752b7cce788ce7680b
Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 include/qom/cpu.h | 1 -
 exec.c            | 5 +++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index fa4b0c9..c2fa151 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -209,7 +209,6 @@ typedef struct CPUClass {
     /* Keep non-pointer data at the end to minimize holes.  */
     int gdb_num_core_regs;
     bool gdb_stop_before_watchpoint;
-    bool tcg_initialized;
 } CPUClass;
 
 #ifdef HOST_WORDS_BIGENDIAN
diff --git a/exec.c b/exec.c
index 97a24a8..8b579c0 100644
--- a/exec.c
+++ b/exec.c
@@ -792,11 +792,12 @@ void cpu_exec_initfn(CPUState *cpu)
 void cpu_exec_realizefn(CPUState *cpu, Error **errp)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
+    static bool tcg_target_initialized;
 
     cpu_list_add(cpu);
 
-    if (tcg_enabled() && !cc->tcg_initialized) {
-        cc->tcg_initialized = true;
+    if (tcg_enabled() && !tcg_target_initialized) {
+        tcg_target_initialized = true;
         cc->tcg_initialize();
     }
 
-- 
2.7.4

Re: [Qemu-devel] [PATCH for 2.11 1/5] qom: move CPUClass.tcg_initialize to a global

[Eduardo Habkost]

On Fri, Nov 10, 2017 at 02:53:42PM -0500, Emilio G. Cota wrote:
> 55c3cee ("qom: Introduce CPUClass.tcg_initialize", 2017-10-24)
> introduces a per-CPUClass bool that we check so that the target CPU
> is initialized for TCG only once. This works well except when
> we end up creating more than one CPUClass, in which case we end
> up incorrectly initializing TCG more than once, i.e. once for
> each CPUClass.
> 
> This can be replicated with:
>   $ aarch64-softmmu/qemu-system-aarch64 -machine xlnx-zcu102 -smp 6 \
>       -global driver=xlnx,,zynqmp,property=has_rpu,value=on
> In this case the class name of the "RPUs" is prefixed by "cortex-r5-",
> whereas the "regular" CPUs are prefixed by "cortex-a53-". This
> results in two CPUClass instances being created.
> 
> Fix it by introducing a static variable, so that only the first
> target CPU being initialized will initialize the target-dependent
> part of TCG, regardless of CPUClass instances.
> 
> Fixes: 55c3ceef61fcf06fc98ddc752b7cce788ce7680b
> Signed-off-by: Emilio G. Cota <cota@braap.org>

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

-- 
Eduardo

Re: [Qemu-devel] [PATCH for 2.11 1/5] qom: move CPUClass.tcg_initialize to a global

[Alistair Francis]

On Fri, Nov 10, 2017 at 12:23 PM, Eduardo Habkost <ehabkost@redhat.com> wrote:
> On Fri, Nov 10, 2017 at 02:53:42PM -0500, Emilio G. Cota wrote:
>> 55c3cee ("qom: Introduce CPUClass.tcg_initialize", 2017-10-24)
>> introduces a per-CPUClass bool that we check so that the target CPU
>> is initialized for TCG only once. This works well except when
>> we end up creating more than one CPUClass, in which case we end
>> up incorrectly initializing TCG more than once, i.e. once for
>> each CPUClass.
>>
>> This can be replicated with:
>>   $ aarch64-softmmu/qemu-system-aarch64 -machine xlnx-zcu102 -smp 6 \
>>       -global driver=xlnx,,zynqmp,property=has_rpu,value=on
>> In this case the class name of the "RPUs" is prefixed by "cortex-r5-",
>> whereas the "regular" CPUs are prefixed by "cortex-a53-". This
>> results in two CPUClass instances being created.
>>
>> Fix it by introducing a static variable, so that only the first
>> target CPU being initialized will initialize the target-dependent
>> part of TCG, regardless of CPUClass instances.
>>
>> Fixes: 55c3ceef61fcf06fc98ddc752b7cce788ce7680b
>> Signed-off-by: Emilio G. Cota <cota@braap.org>
>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Tested-by: Alistair Francis <alistair.francis@xilinx.com>

Alistair

>
> --
> Eduardo
>

Re: [Qemu-devel] [PATCH for 2.11 1/5] qom: move CPUClass.tcg_initialize to a global

[Richard Henderson]

On 11/10/2017 08:53 PM, Emilio G. Cota wrote:
> 55c3cee ("qom: Introduce CPUClass.tcg_initialize", 2017-10-24)
> introduces a per-CPUClass bool that we check so that the target CPU
> is initialized for TCG only once. This works well except when
> we end up creating more than one CPUClass, in which case we end
> up incorrectly initializing TCG more than once, i.e. once for
> each CPUClass.

... more than one CPUClass for a given translator.

Ideally, cortex-r5 and cortex-a53 would have a common parent class which would
hold all of the bits that are common between them, including the translator.

That said,

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~

[Qemu-devel] [PATCH for 2.11 2/5] xlnx-zynqmp: Properly support the smp command line option

[Emilio G. Cota]

From: Alistair Francis <alistair.francis@xilinx.com>

Allow the -smp command line option to control the number of CPUs we
create.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Emilio G. Cota <cota@braap.org>
Tested-by: Emilio G. Cota <cota@braap.org>
---
 hw/arm/xlnx-zcu102.c |  3 ++-
 hw/arm/xlnx-zynqmp.c | 26 ++++++++++++++++----------
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
index e2d15a1..7ec03da 100644
--- a/hw/arm/xlnx-zcu102.c
+++ b/hw/arm/xlnx-zcu102.c
@@ -235,7 +235,8 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data)
 {
     MachineClass *mc = MACHINE_CLASS(oc);
 
-    mc->desc = "Xilinx ZynqMP ZCU102 board";
+    mc->desc = "Xilinx ZynqMP ZCU102 board with 4xA53s and 2xR5s based on " \
+               "the value of smp";
     mc->init = xlnx_zcu102_init;
     mc->block_default_type = IF_IDE;
     mc->units_per_default_bus = 1;
diff --git a/hw/arm/xlnx-zynqmp.c b/hw/arm/xlnx-zynqmp.c
index d4b6560..c707c66 100644
--- a/hw/arm/xlnx-zynqmp.c
+++ b/hw/arm/xlnx-zynqmp.c
@@ -98,8 +98,9 @@ static void xlnx_zynqmp_create_rpu(XlnxZynqMPState *s, const char *boot_cpu,
 {
     Error *err = NULL;
     int i;
+    int num_rpus = MIN(smp_cpus - XLNX_ZYNQMP_NUM_APU_CPUS, XLNX_ZYNQMP_NUM_RPU_CPUS);
 
-    for (i = 0; i < XLNX_ZYNQMP_NUM_RPU_CPUS; i++) {
+    for (i = 0; i < num_rpus; i++) {
         char *name;
 
         object_initialize(&s->rpu_cpu[i], sizeof(s->rpu_cpu[i]),
@@ -132,8 +133,9 @@ static void xlnx_zynqmp_init(Object *obj)
 {
     XlnxZynqMPState *s = XLNX_ZYNQMP(obj);
     int i;
+    int num_apus = MIN(smp_cpus, XLNX_ZYNQMP_NUM_APU_CPUS);
 
-    for (i = 0; i < XLNX_ZYNQMP_NUM_APU_CPUS; i++) {
+    for (i = 0; i < num_apus; i++) {
         object_initialize(&s->apu_cpu[i], sizeof(s->apu_cpu[i]),
                           "cortex-a53-" TYPE_ARM_CPU);
         object_property_add_child(obj, "apu-cpu[*]", OBJECT(&s->apu_cpu[i]),
@@ -182,6 +184,7 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error **errp)
     MemoryRegion *system_memory = get_system_memory();
     uint8_t i;
     uint64_t ram_size;
+    int num_apus = MIN(smp_cpus, XLNX_ZYNQMP_NUM_APU_CPUS);
     const char *boot_cpu = s->boot_cpu ? s->boot_cpu : "apu-cpu[0]";
     ram_addr_t ddr_low_size, ddr_high_size;
     qemu_irq gic_spi[GIC_NUM_SPI_INTR];
@@ -233,10 +236,10 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error **errp)
 
     qdev_prop_set_uint32(DEVICE(&s->gic), "num-irq", GIC_NUM_SPI_INTR + 32);
     qdev_prop_set_uint32(DEVICE(&s->gic), "revision", 2);
-    qdev_prop_set_uint32(DEVICE(&s->gic), "num-cpu", XLNX_ZYNQMP_NUM_APU_CPUS);
+    qdev_prop_set_uint32(DEVICE(&s->gic), "num-cpu", num_apus);
 
     /* Realize APUs before realizing the GIC. KVM requires this.  */
-    for (i = 0; i < XLNX_ZYNQMP_NUM_APU_CPUS; i++) {
+    for (i = 0; i < num_apus; i++) {
         char *name;
 
         object_property_set_int(OBJECT(&s->apu_cpu[i]), QEMU_PSCI_CONDUIT_SMC,
@@ -292,7 +295,7 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    for (i = 0; i < XLNX_ZYNQMP_NUM_APU_CPUS; i++) {
+    for (i = 0; i < num_apus; i++) {
         qemu_irq irq;
 
         sysbus_connect_irq(SYS_BUS_DEVICE(&s->gic), i,
@@ -307,11 +310,14 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error **errp)
     }
 
     if (s->has_rpu) {
-        xlnx_zynqmp_create_rpu(s, boot_cpu, &err);
-        if (err) {
-            error_propagate(errp, err);
-            return;
-        }
+        info_report("The 'has_rpu' property is no longer required, to use the "
+                    "RPUs just use -smp 6.");
+    }
+
+    xlnx_zynqmp_create_rpu(s, boot_cpu, &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
     }
 
     if (!s->boot_cpu_ptr) {
-- 
2.7.4

[Qemu-devel] [PATCH for 2.11 3/5] xlnx-zcu102: Add an info message deprecating the EP108

[Emilio G. Cota]

From: Alistair Francis <alistair.francis@xilinx.com>

The EP108 was an early access development board that is no longer used.
Add an info message to convert any users to the ZCU102 instead. On QEMU
they are both identical.

This patch also updated the qemu-doc.texi file to indicate that the
EP108 has been deprecated.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Emilio G. Cota <cota@braap.org>
---
 qemu-doc.texi        | 7 +++++++
 hw/arm/xlnx-zcu102.c | 3 +++
 2 files changed, 10 insertions(+)

diff --git a/qemu-doc.texi b/qemu-doc.texi
index 8c10956..d383ac4 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -2537,6 +2537,13 @@ or ``ivshmem-doorbell`` device types.
 The ``spapr-pci-vfio-host-bridge'' device type is replaced by
 the ``spapr-pci-host-bridge'' device type.
 
+@section System emulator machines
+
+@subsection Xilinx EP108 (since 2.11.0)
+
+The ``xlnx-ep108'' machine has been replaced by the ``xlnx-zcu102'' machine.
+The ``xlnx-zcu102'' machine has the same features and capabilites in QEMU.
+
 @node License
 @appendix License
 
diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
index 7ec03da..adddd23 100644
--- a/hw/arm/xlnx-zcu102.c
+++ b/hw/arm/xlnx-zcu102.c
@@ -164,6 +164,9 @@ static void xlnx_ep108_init(MachineState *machine)
 {
     XlnxZCU102 *s = EP108_MACHINE(machine);
 
+    info_report("The Xilinx EP108 machine is deprecated, please use the "
+                "ZCU102 machine instead. It has the same features supported.");
+
     xlnx_zynqmp_init(s, machine);
 }
 
-- 
2.7.4

[Qemu-devel] [PATCH for 2.11 4/5] xlnx-zcu102: Specify the max number of CPUs for the EP108

[Emilio G. Cota]

Just like the zcu102, the ep108 can instantiate several CPUs.

Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 hw/arm/xlnx-zcu102.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
index adddd23..190eb69 100644
--- a/hw/arm/xlnx-zcu102.c
+++ b/hw/arm/xlnx-zcu102.c
@@ -188,6 +188,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data)
     mc->block_default_type = IF_IDE;
     mc->units_per_default_bus = 1;
     mc->ignore_memory_transaction_failures = true;
+    mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
 }
 
 static const TypeInfo xlnx_ep108_machine_init_typeinfo = {
-- 
2.7.4

Re: [Qemu-devel] [PATCH for 2.11 4/5] xlnx-zcu102: Specify the max number of CPUs for the EP108

[Alistair Francis]

On Fri, Nov 10, 2017 at 11:53 AM, Emilio G. Cota <cota@braap.org> wrote:
> Just like the zcu102, the ep108 can instantiate several CPUs.
>
> Signed-off-by: Emilio G. Cota <cota@braap.org>

I completely missed this, thanks for the patch.

Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>

Alistair

> ---
>  hw/arm/xlnx-zcu102.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
> index adddd23..190eb69 100644
> --- a/hw/arm/xlnx-zcu102.c
> +++ b/hw/arm/xlnx-zcu102.c
> @@ -188,6 +188,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data)
>      mc->block_default_type = IF_IDE;
>      mc->units_per_default_bus = 1;
>      mc->ignore_memory_transaction_failures = true;
> +    mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
>  }
>
>  static const TypeInfo xlnx_ep108_machine_init_typeinfo = {
> --
> 2.7.4
>
>

[Qemu-devel] [PATCH for 2.11 5/5] hw: add .min_cpus and .default_cpus fields to machine_class

[Emilio G. Cota]

max_cpus needs to be an upper bound on the number of vCPUs
initialized; otherwise TCG region initialization breaks.

Some boards initialize a hard-coded number of vCPUs, which is not
captured by the global max_cpus and therefore breaks TCG initialization.
Fix it by adding the .min_cpus field to machine_class.

This commit also changes some user-facing behaviour: we now die if
-smp is below this hard-coded vCPU minimum instead of silently
ignoring the passed -smp value (sometimes announcing this by printing
a warning). However, the introduction of .default_cpus lessens the
likelihood that users will notice this: if -smp isn't set, we now
assign the value in .default_cpus to both smp_cpus and max_cpus. IOW,
if a user does not set -smp, they always get a correct number of vCPUs.

This change fixes 3468b59 ("tcg: enable multiple TCG contexts in
softmmu", 2017-10-24), which broke TCG initialization for some
ARM boards.

Fixes: 3468b59e18b179bc63c7ce934de912dfa9596122
Reported-by: Thomas Huth <thuth@redhat.com>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 include/hw/boards.h     |  5 +++++
 hw/arm/exynos4_boards.c | 12 ++++--------
 hw/arm/raspi.c          |  2 ++
 hw/arm/xlnx-zcu102.c    |  2 ++
 vl.c                    | 21 ++++++++++++++++++---
 5 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 191a5b3..62f160e 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -102,6 +102,9 @@ typedef struct {
 
 /**
  * MachineClass:
+ * @max_cpus: maximum number of CPUs supported. Default: 1
+ * @min_cpus: minimum number of CPUs supported. Default: 1
+ * @default_cpus: number of CPUs instantiated if none are specified. Default: 1
  * @get_hotplug_handler: this function is called during bus-less
  *    device hotplug. If defined it returns pointer to an instance
  *    of HotplugHandler object, which handles hotplug operation
@@ -167,6 +170,8 @@ struct MachineClass {
     BlockInterfaceType block_default_type;
     int units_per_default_bus;
     int max_cpus;
+    int min_cpus;
+    int default_cpus;
     unsigned int no_serial:1,
         no_parallel:1,
         use_virtcon:1,
diff --git a/hw/arm/exynos4_boards.c b/hw/arm/exynos4_boards.c
index f1441ec..750162c 100644
--- a/hw/arm/exynos4_boards.c
+++ b/hw/arm/exynos4_boards.c
@@ -27,7 +27,6 @@
 #include "qemu-common.h"
 #include "cpu.h"
 #include "sysemu/sysemu.h"
-#include "sysemu/qtest.h"
 #include "hw/sysbus.h"
 #include "net/net.h"
 #include "hw/arm/arm.h"
@@ -129,13 +128,6 @@ exynos4_boards_init_common(MachineState *machine,
                            Exynos4BoardType board_type)
 {
     Exynos4BoardState *s = g_new(Exynos4BoardState, 1);
-    MachineClass *mc = MACHINE_GET_CLASS(machine);
-
-    if (smp_cpus != EXYNOS4210_NCPUS && !qtest_enabled()) {
-        error_report("%s board supports only %d CPU cores, ignoring smp_cpus"
-                     " value",
-                     mc->name, EXYNOS4210_NCPUS);
-    }
 
     exynos4_board_binfo.ram_size = exynos4_board_ram_size[board_type];
     exynos4_board_binfo.board_id = exynos4_board_id[board_type];
@@ -189,6 +181,8 @@ static void nuri_class_init(ObjectClass *oc, void *data)
     mc->desc = "Samsung NURI board (Exynos4210)";
     mc->init = nuri_init;
     mc->max_cpus = EXYNOS4210_NCPUS;
+    mc->min_cpus = EXYNOS4210_NCPUS;
+    mc->default_cpus = EXYNOS4210_NCPUS;
     mc->ignore_memory_transaction_failures = true;
 }
 
@@ -205,6 +199,8 @@ static void smdkc210_class_init(ObjectClass *oc, void *data)
     mc->desc = "Samsung SMDKC210 board (Exynos4210)";
     mc->init = smdkc210_init;
     mc->max_cpus = EXYNOS4210_NCPUS;
+    mc->min_cpus = EXYNOS4210_NCPUS;
+    mc->default_cpus = EXYNOS4210_NCPUS;
     mc->ignore_memory_transaction_failures = true;
 }
 
diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c
index 5941c9f..cd5fa8c 100644
--- a/hw/arm/raspi.c
+++ b/hw/arm/raspi.c
@@ -167,6 +167,8 @@ static void raspi2_machine_init(MachineClass *mc)
     mc->no_floppy = 1;
     mc->no_cdrom = 1;
     mc->max_cpus = BCM2836_NCPUS;
+    mc->min_cpus = BCM2836_NCPUS;
+    mc->default_cpus = BCM2836_NCPUS;
     mc->default_ram_size = 1024 * 1024 * 1024;
     mc->ignore_memory_transaction_failures = true;
 };
diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
index 190eb69..9631a53 100644
--- a/hw/arm/xlnx-zcu102.c
+++ b/hw/arm/xlnx-zcu102.c
@@ -189,6 +189,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data)
     mc->units_per_default_bus = 1;
     mc->ignore_memory_transaction_failures = true;
     mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
+    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
 }
 
 static const TypeInfo xlnx_ep108_machine_init_typeinfo = {
@@ -246,6 +247,7 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data)
     mc->units_per_default_bus = 1;
     mc->ignore_memory_transaction_failures = true;
     mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
+    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
 }
 
 static const TypeInfo xlnx_zcu102_machine_init_typeinfo = {
diff --git a/vl.c b/vl.c
index ec29909..7372424 100644
--- a/vl.c
+++ b/vl.c
@@ -160,8 +160,8 @@ Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES];
 Chardev *sclp_hds[MAX_SCLP_CONSOLES];
 int win2k_install_hack = 0;
 int singlestep = 0;
-int smp_cpus = 1;
-unsigned int max_cpus = 1;
+int smp_cpus;
+unsigned int max_cpus;
 int smp_cores = 1;
 int smp_threads = 1;
 int acpi_enabled = 1;
@@ -4327,9 +4327,24 @@ int main(int argc, char **argv, char **envp)
         exit(0);
     }
 
+    /* machine_class: default to UP */
+    machine_class->max_cpus = machine_class->max_cpus ?: 1;
+    machine_class->min_cpus = machine_class->min_cpus ?: 1;
+    machine_class->default_cpus = machine_class->default_cpus ?: 1;
+
+    /* default to machine_class->default_cpus */
+    smp_cpus = machine_class->default_cpus;
+    max_cpus = machine_class->default_cpus;
+
     smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
 
-    machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */
+    /* sanity-check smp_cpus and max_cpus against machine_class */
+    if (smp_cpus < machine_class->min_cpus) {
+        error_report("Invalid SMP CPUs %d. The min CPUs "
+                     "supported by machine '%s' is %d", smp_cpus,
+                     machine_class->name, machine_class->min_cpus);
+        exit(1);
+    }
     if (max_cpus > machine_class->max_cpus) {
         error_report("Invalid SMP CPUs %d. The max CPUs "
                      "supported by machine '%s' is %d", max_cpus,
-- 
2.7.4

Re: [Qemu-devel] [PATCH for 2.11 5/5] hw: add .min_cpus and .default_cpus fields to machine_class

[Eduardo Habkost]

On Fri, Nov 10, 2017 at 02:53:46PM -0500, Emilio G. Cota wrote:
> max_cpus needs to be an upper bound on the number of vCPUs
> initialized; otherwise TCG region initialization breaks.
> 
> Some boards initialize a hard-coded number of vCPUs, which is not
> captured by the global max_cpus and therefore breaks TCG initialization.
> Fix it by adding the .min_cpus field to machine_class.
> 
> This commit also changes some user-facing behaviour: we now die if
> -smp is below this hard-coded vCPU minimum instead of silently
> ignoring the passed -smp value (sometimes announcing this by printing
> a warning). However, the introduction of .default_cpus lessens the
> likelihood that users will notice this: if -smp isn't set, we now
> assign the value in .default_cpus to both smp_cpus and max_cpus. IOW,
> if a user does not set -smp, they always get a correct number of vCPUs.
> 
> This change fixes 3468b59 ("tcg: enable multiple TCG contexts in
> softmmu", 2017-10-24), which broke TCG initialization for some
> ARM boards.
> 
> Fixes: 3468b59e18b179bc63c7ce934de912dfa9596122
> Reported-by: Thomas Huth <thuth@redhat.com>
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Emilio G. Cota <cota@braap.org>
> ---
>  include/hw/boards.h     |  5 +++++
>  hw/arm/exynos4_boards.c | 12 ++++--------
>  hw/arm/raspi.c          |  2 ++
>  hw/arm/xlnx-zcu102.c    |  2 ++
>  vl.c                    | 21 ++++++++++++++++++---
>  5 files changed, 31 insertions(+), 11 deletions(-)
> 
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 191a5b3..62f160e 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -102,6 +102,9 @@ typedef struct {
>  
>  /**
>   * MachineClass:
> + * @max_cpus: maximum number of CPUs supported. Default: 1
> + * @min_cpus: minimum number of CPUs supported. Default: 1
> + * @default_cpus: number of CPUs instantiated if none are specified. Default: 1
>   * @get_hotplug_handler: this function is called during bus-less
>   *    device hotplug. If defined it returns pointer to an instance
>   *    of HotplugHandler object, which handles hotplug operation
> @@ -167,6 +170,8 @@ struct MachineClass {
>      BlockInterfaceType block_default_type;
>      int units_per_default_bus;
>      int max_cpus;
> +    int min_cpus;
> +    int default_cpus;
>      unsigned int no_serial:1,
>          no_parallel:1,
>          use_virtcon:1,
> diff --git a/hw/arm/exynos4_boards.c b/hw/arm/exynos4_boards.c
> index f1441ec..750162c 100644
> --- a/hw/arm/exynos4_boards.c
> +++ b/hw/arm/exynos4_boards.c
> @@ -27,7 +27,6 @@
>  #include "qemu-common.h"
>  #include "cpu.h"
>  #include "sysemu/sysemu.h"
> -#include "sysemu/qtest.h"
>  #include "hw/sysbus.h"
>  #include "net/net.h"
>  #include "hw/arm/arm.h"
> @@ -129,13 +128,6 @@ exynos4_boards_init_common(MachineState *machine,
>                             Exynos4BoardType board_type)
>  {
>      Exynos4BoardState *s = g_new(Exynos4BoardState, 1);
> -    MachineClass *mc = MACHINE_GET_CLASS(machine);
> -
> -    if (smp_cpus != EXYNOS4210_NCPUS && !qtest_enabled()) {
> -        error_report("%s board supports only %d CPU cores, ignoring smp_cpus"
> -                     " value",
> -                     mc->name, EXYNOS4210_NCPUS);
> -    }
>  
>      exynos4_board_binfo.ram_size = exynos4_board_ram_size[board_type];
>      exynos4_board_binfo.board_id = exynos4_board_id[board_type];
> @@ -189,6 +181,8 @@ static void nuri_class_init(ObjectClass *oc, void *data)
>      mc->desc = "Samsung NURI board (Exynos4210)";
>      mc->init = nuri_init;
>      mc->max_cpus = EXYNOS4210_NCPUS;
> +    mc->min_cpus = EXYNOS4210_NCPUS;
> +    mc->default_cpus = EXYNOS4210_NCPUS;
>      mc->ignore_memory_transaction_failures = true;
>  }
>  
> @@ -205,6 +199,8 @@ static void smdkc210_class_init(ObjectClass *oc, void *data)
>      mc->desc = "Samsung SMDKC210 board (Exynos4210)";
>      mc->init = smdkc210_init;
>      mc->max_cpus = EXYNOS4210_NCPUS;
> +    mc->min_cpus = EXYNOS4210_NCPUS;
> +    mc->default_cpus = EXYNOS4210_NCPUS;
>      mc->ignore_memory_transaction_failures = true;
>  }
>  
> diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c
> index 5941c9f..cd5fa8c 100644
> --- a/hw/arm/raspi.c
> +++ b/hw/arm/raspi.c
> @@ -167,6 +167,8 @@ static void raspi2_machine_init(MachineClass *mc)
>      mc->no_floppy = 1;
>      mc->no_cdrom = 1;
>      mc->max_cpus = BCM2836_NCPUS;
> +    mc->min_cpus = BCM2836_NCPUS;
> +    mc->default_cpus = BCM2836_NCPUS;
>      mc->default_ram_size = 1024 * 1024 * 1024;
>      mc->ignore_memory_transaction_failures = true;
>  };
> diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
> index 190eb69..9631a53 100644
> --- a/hw/arm/xlnx-zcu102.c
> +++ b/hw/arm/xlnx-zcu102.c
> @@ -189,6 +189,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data)
>      mc->units_per_default_bus = 1;
>      mc->ignore_memory_transaction_failures = true;
>      mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
> +    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
>  }
>  
>  static const TypeInfo xlnx_ep108_machine_init_typeinfo = {
> @@ -246,6 +247,7 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data)
>      mc->units_per_default_bus = 1;
>      mc->ignore_memory_transaction_failures = true;
>      mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
> +    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
>  }
>  
>  static const TypeInfo xlnx_zcu102_machine_init_typeinfo = {
> diff --git a/vl.c b/vl.c
> index ec29909..7372424 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -160,8 +160,8 @@ Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES];
>  Chardev *sclp_hds[MAX_SCLP_CONSOLES];
>  int win2k_install_hack = 0;
>  int singlestep = 0;
> -int smp_cpus = 1;
> -unsigned int max_cpus = 1;
> +int smp_cpus;
> +unsigned int max_cpus;
>  int smp_cores = 1;
>  int smp_threads = 1;
>  int acpi_enabled = 1;
> @@ -4327,9 +4327,24 @@ int main(int argc, char **argv, char **envp)
>          exit(0);
>      }
>  
> +    /* machine_class: default to UP */
> +    machine_class->max_cpus = machine_class->max_cpus ?: 1;
> +    machine_class->min_cpus = machine_class->min_cpus ?: 1;
> +    machine_class->default_cpus = machine_class->default_cpus ?: 1;

This is consistent with the existing code that initialized
max_cpus, but I'd prefer to initialize these defaults inside
hw/core/machine.c:machine_class_init().  It can be done in a
follow-up patch after 2.11, though.

> +
> +    /* default to machine_class->default_cpus */
> +    smp_cpus = machine_class->default_cpus;
> +    max_cpus = machine_class->default_cpus;
> +
>      smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
>  
> -    machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */
> +    /* sanity-check smp_cpus and max_cpus against machine_class */
> +    if (smp_cpus < machine_class->min_cpus) {
> +        error_report("Invalid SMP CPUs %d. The min CPUs "
> +                     "supported by machine '%s' is %d", smp_cpus,
> +                     machine_class->name, machine_class->min_cpus);
> +        exit(1);
> +    }
>      if (max_cpus > machine_class->max_cpus) {
>          error_report("Invalid SMP CPUs %d. The max CPUs "
>                       "supported by machine '%s' is %d", max_cpus,

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

-- 
Eduardo

Re: [Qemu-devel] [PATCH for 2.11 5/5] hw: add .min_cpus and .default_cpus fields to machine_class

[Alistair Francis]

On Fri, Nov 10, 2017 at 11:53 AM, Emilio G. Cota <cota@braap.org> wrote:
> max_cpus needs to be an upper bound on the number of vCPUs
> initialized; otherwise TCG region initialization breaks.
>
> Some boards initialize a hard-coded number of vCPUs, which is not
> captured by the global max_cpus and therefore breaks TCG initialization.
> Fix it by adding the .min_cpus field to machine_class.
>
> This commit also changes some user-facing behaviour: we now die if
> -smp is below this hard-coded vCPU minimum instead of silently
> ignoring the passed -smp value (sometimes announcing this by printing
> a warning). However, the introduction of .default_cpus lessens the
> likelihood that users will notice this: if -smp isn't set, we now
> assign the value in .default_cpus to both smp_cpus and max_cpus. IOW,
> if a user does not set -smp, they always get a correct number of vCPUs.
>
> This change fixes 3468b59 ("tcg: enable multiple TCG contexts in
> softmmu", 2017-10-24), which broke TCG initialization for some
> ARM boards.
>
> Fixes: 3468b59e18b179bc63c7ce934de912dfa9596122
> Reported-by: Thomas Huth <thuth@redhat.com>
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Emilio G. Cota <cota@braap.org>

Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>

Alistair

> ---
>  include/hw/boards.h     |  5 +++++
>  hw/arm/exynos4_boards.c | 12 ++++--------
>  hw/arm/raspi.c          |  2 ++
>  hw/arm/xlnx-zcu102.c    |  2 ++
>  vl.c                    | 21 ++++++++++++++++++---
>  5 files changed, 31 insertions(+), 11 deletions(-)
>
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 191a5b3..62f160e 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -102,6 +102,9 @@ typedef struct {
>
>  /**
>   * MachineClass:
> + * @max_cpus: maximum number of CPUs supported. Default: 1
> + * @min_cpus: minimum number of CPUs supported. Default: 1
> + * @default_cpus: number of CPUs instantiated if none are specified. Default: 1
>   * @get_hotplug_handler: this function is called during bus-less
>   *    device hotplug. If defined it returns pointer to an instance
>   *    of HotplugHandler object, which handles hotplug operation
> @@ -167,6 +170,8 @@ struct MachineClass {
>      BlockInterfaceType block_default_type;
>      int units_per_default_bus;
>      int max_cpus;
> +    int min_cpus;
> +    int default_cpus;
>      unsigned int no_serial:1,
>          no_parallel:1,
>          use_virtcon:1,
> diff --git a/hw/arm/exynos4_boards.c b/hw/arm/exynos4_boards.c
> index f1441ec..750162c 100644
> --- a/hw/arm/exynos4_boards.c
> +++ b/hw/arm/exynos4_boards.c
> @@ -27,7 +27,6 @@
>  #include "qemu-common.h"
>  #include "cpu.h"
>  #include "sysemu/sysemu.h"
> -#include "sysemu/qtest.h"
>  #include "hw/sysbus.h"
>  #include "net/net.h"
>  #include "hw/arm/arm.h"
> @@ -129,13 +128,6 @@ exynos4_boards_init_common(MachineState *machine,
>                             Exynos4BoardType board_type)
>  {
>      Exynos4BoardState *s = g_new(Exynos4BoardState, 1);
> -    MachineClass *mc = MACHINE_GET_CLASS(machine);
> -
> -    if (smp_cpus != EXYNOS4210_NCPUS && !qtest_enabled()) {
> -        error_report("%s board supports only %d CPU cores, ignoring smp_cpus"
> -                     " value",
> -                     mc->name, EXYNOS4210_NCPUS);
> -    }
>
>      exynos4_board_binfo.ram_size = exynos4_board_ram_size[board_type];
>      exynos4_board_binfo.board_id = exynos4_board_id[board_type];
> @@ -189,6 +181,8 @@ static void nuri_class_init(ObjectClass *oc, void *data)
>      mc->desc = "Samsung NURI board (Exynos4210)";
>      mc->init = nuri_init;
>      mc->max_cpus = EXYNOS4210_NCPUS;
> +    mc->min_cpus = EXYNOS4210_NCPUS;
> +    mc->default_cpus = EXYNOS4210_NCPUS;
>      mc->ignore_memory_transaction_failures = true;
>  }
>
> @@ -205,6 +199,8 @@ static void smdkc210_class_init(ObjectClass *oc, void *data)
>      mc->desc = "Samsung SMDKC210 board (Exynos4210)";
>      mc->init = smdkc210_init;
>      mc->max_cpus = EXYNOS4210_NCPUS;
> +    mc->min_cpus = EXYNOS4210_NCPUS;
> +    mc->default_cpus = EXYNOS4210_NCPUS;
>      mc->ignore_memory_transaction_failures = true;
>  }
>
> diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c
> index 5941c9f..cd5fa8c 100644
> --- a/hw/arm/raspi.c
> +++ b/hw/arm/raspi.c
> @@ -167,6 +167,8 @@ static void raspi2_machine_init(MachineClass *mc)
>      mc->no_floppy = 1;
>      mc->no_cdrom = 1;
>      mc->max_cpus = BCM2836_NCPUS;
> +    mc->min_cpus = BCM2836_NCPUS;
> +    mc->default_cpus = BCM2836_NCPUS;
>      mc->default_ram_size = 1024 * 1024 * 1024;
>      mc->ignore_memory_transaction_failures = true;
>  };
> diff --git a/hw/arm/xlnx-zcu102.c b/hw/arm/xlnx-zcu102.c
> index 190eb69..9631a53 100644
> --- a/hw/arm/xlnx-zcu102.c
> +++ b/hw/arm/xlnx-zcu102.c
> @@ -189,6 +189,7 @@ static void xlnx_ep108_machine_class_init(ObjectClass *oc, void *data)
>      mc->units_per_default_bus = 1;
>      mc->ignore_memory_transaction_failures = true;
>      mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
> +    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
>  }
>
>  static const TypeInfo xlnx_ep108_machine_init_typeinfo = {
> @@ -246,6 +247,7 @@ static void xlnx_zcu102_machine_class_init(ObjectClass *oc, void *data)
>      mc->units_per_default_bus = 1;
>      mc->ignore_memory_transaction_failures = true;
>      mc->max_cpus = XLNX_ZYNQMP_NUM_APU_CPUS + XLNX_ZYNQMP_NUM_RPU_CPUS;
> +    mc->default_cpus = XLNX_ZYNQMP_NUM_APU_CPUS;
>  }
>
>  static const TypeInfo xlnx_zcu102_machine_init_typeinfo = {
> diff --git a/vl.c b/vl.c
> index ec29909..7372424 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -160,8 +160,8 @@ Chardev *virtcon_hds[MAX_VIRTIO_CONSOLES];
>  Chardev *sclp_hds[MAX_SCLP_CONSOLES];
>  int win2k_install_hack = 0;
>  int singlestep = 0;
> -int smp_cpus = 1;
> -unsigned int max_cpus = 1;
> +int smp_cpus;
> +unsigned int max_cpus;
>  int smp_cores = 1;
>  int smp_threads = 1;
>  int acpi_enabled = 1;
> @@ -4327,9 +4327,24 @@ int main(int argc, char **argv, char **envp)
>          exit(0);
>      }
>
> +    /* machine_class: default to UP */
> +    machine_class->max_cpus = machine_class->max_cpus ?: 1;
> +    machine_class->min_cpus = machine_class->min_cpus ?: 1;
> +    machine_class->default_cpus = machine_class->default_cpus ?: 1;
> +
> +    /* default to machine_class->default_cpus */
> +    smp_cpus = machine_class->default_cpus;
> +    max_cpus = machine_class->default_cpus;
> +
>      smp_parse(qemu_opts_find(qemu_find_opts("smp-opts"), NULL));
>
> -    machine_class->max_cpus = machine_class->max_cpus ?: 1; /* Default to UP */
> +    /* sanity-check smp_cpus and max_cpus against machine_class */
> +    if (smp_cpus < machine_class->min_cpus) {
> +        error_report("Invalid SMP CPUs %d. The min CPUs "
> +                     "supported by machine '%s' is %d", smp_cpus,
> +                     machine_class->name, machine_class->min_cpus);
> +        exit(1);
> +    }
>      if (max_cpus > machine_class->max_cpus) {
>          error_report("Invalid SMP CPUs %d. The max CPUs "
>                       "supported by machine '%s' is %d", max_cpus,
> --
> 2.7.4
>
>

Re: [Qemu-devel] [PATCH for 2.11 0/5] TCG/ARM fixes for 2.11

[Peter Maydell]

On 10 November 2017 at 19:53, Emilio G. Cota <cota@braap.org> wrote:
> Some MachineClass changes to fix TCG initialization of some
> ARM boards for 2.11. This was originally reported by Thomas Huth in [1],
> where Peter suggested a way to fix it. Further discussion in
> another thread [2] followed up on this.
>
> As a result of that follow-up discussion we also got some Zynq changes from
> Alistair [3], which I'm including here since in order to test them
> we need the first patch in this series.
>
> Thanks,
>
>                 Emilio
>
> [1] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg00078.html
> [2] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg00502.html
> [3] https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg01842.html
>
> Alistair Francis (2):
>   xlnx-zynqmp: Properly support the smp command line option
>   xlnx-zcu102: Add an info message deprecating the EP108
>
> Emilio G. Cota (3):
>   qom: move CPUClass.tcg_initialize to a global
>   xlnx-zcu102: Specify the max number of CPUs for the EP108
>   hw: add .min_cpus and .default_cpus fields to machine_class
>
>  qemu-doc.texi           |  7 +++++++
>  include/hw/boards.h     |  5 +++++
>  include/qom/cpu.h       |  1 -
>  exec.c                  |  5 +++--
>  hw/arm/exynos4_boards.c | 12 ++++--------
>  hw/arm/raspi.c          |  2 ++
>  hw/arm/xlnx-zcu102.c    |  9 ++++++++-
>  hw/arm/xlnx-zynqmp.c    | 26 ++++++++++++++++----------
>  vl.c                    | 21 ++++++++++++++++++---
>  9 files changed, 63 insertions(+), 25 deletions(-)

Since this is fixing Arm boards and I'm putting together an
arm pullreq anyway, I'm applying this to target-arm.next.
(Eduardo's reviewed the patches which touch the MachineClass
and option parsing code.)

thanks
-- PMM