From: Salil Mehta <salil.mehta@huawei.com>
To: "Salil Mehta" <salil.mehta@huawei.com>,
"Philippe Mathieu-Daudé" <philmd@linaro.org>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Cc: "maz@kernel.org" <maz@kernel.org>,
"jean-philippe@linaro.org" <jean-philippe@linaro.org>,
Jonathan Cameron <jonathan.cameron@huawei.com>,
"lpieralisi@kernel.org" <lpieralisi@kernel.org>,
"peter.maydell@linaro.org" <peter.maydell@linaro.org>,
"richard.henderson@linaro.org" <richard.henderson@linaro.org>,
"imammedo@redhat.com" <imammedo@redhat.com>,
"andrew.jones@linux.dev" <andrew.jones@linux.dev>,
"david@redhat.com" <david@redhat.com>,
"eric.auger@redhat.com" <eric.auger@redhat.com>,
"will@kernel.org" <will@kernel.org>,
"ardb@kernel.org" <ardb@kernel.org>,
"oliver.upton@linux.dev" <oliver.upton@linux.dev>,
"pbonzini@redhat.com" <pbonzini@redhat.com>,
"mst@redhat.com" <mst@redhat.com>,
"gshan@redhat.com" <gshan@redhat.com>,
"rafael@kernel.org" <rafael@kernel.org>,
"borntraeger@linux.ibm.com" <borntraeger@linux.ibm.com>,
"alex.bennee@linaro.org" <alex.bennee@linaro.org>,
"linux@armlinux.org.uk" <linux@armlinux.org.uk>,
"darren@os.amperecomputing.com" <darren@os.amperecomputing.com>,
"ilkka@os.amperecomputing.com" <ilkka@os.amperecomputing.com>,
"vishnu@os.amperecomputing.com" <vishnu@os.amperecomputing.com>,
"karl.heubaum@oracle.com" <karl.heubaum@oracle.com>,
"miguel.luis@oracle.com" <miguel.luis@oracle.com>,
"salil.mehta@opnsrc.net" <salil.mehta@opnsrc.net>,
zhukeqian <zhukeqian1@huawei.com>,
"wangxiongfeng (C)" <wangxiongfeng2@huawei.com>,
"wangyanan (Y)" <wangyanan55@huawei.com>,
"jiakernel2@gmail.com" <jiakernel2@gmail.com>,
"maobibo@loongson.cn" <maobibo@loongson.cn>,
"lixianglai@loongson.cn" <lixianglai@loongson.cn>
Subject: RE: [PATCH RFC V2 31/37] physmem,gdbstub: Common helping funcs/changes to *unrealize* vCPU
Date: Wed, 4 Oct 2023 09:17:52 +0000 [thread overview]
Message-ID: <d5191246e108473c95fb6e9a6925f1bd@huawei.com> (raw)
Message-ID: <20231004091752.B9VUBuycVzKUaXG2uhrOFejOmdKkGGxA5vDeb28zS38@z> (raw)
In-Reply-To: <7e02ed766bd54b7184e349611e61cf12@huawei.com>
Hi Phil/Richard,
> From: qemu-arm-bounces+salil.mehta=huawei.com@nongnu.org <qemu-arm-
> bounces+salil.mehta=huawei.com@nongnu.org> On Behalf Of Salil Mehta via
> Sent: Tuesday, October 3, 2023 11:23 AM
>
> Hi Phil,
>
> > From: Philippe Mathieu-Daudé <philmd@linaro.org>
> > Sent: Tuesday, October 3, 2023 7:34 AM
> > To: Salil Mehta <salil.mehta@huawei.com>; qemu-devel@nongnu.org; qemu-
> > arm@nongnu.org
> > Cc: maz@kernel.org; jean-philippe@linaro.org; Jonathan Cameron
> > <jonathan.cameron@huawei.com>; lpieralisi@kernel.org;
> > peter.maydell@linaro.org; richard.henderson@linaro.org;
> > imammedo@redhat.com; andrew.jones@linux.dev; david@redhat.com;
> > eric.auger@redhat.com; will@kernel.org; ardb@kernel.org;
> > oliver.upton@linux.dev; pbonzini@redhat.com; mst@redhat.com;
> > gshan@redhat.com; rafael@kernel.org; borntraeger@linux.ibm.com;
> > alex.bennee@linaro.org; linux@armlinux.org.uk;
> > darren@os.amperecomputing.com; ilkka@os.amperecomputing.com;
> > vishnu@os.amperecomputing.com; karl.heubaum@oracle.com;
> > miguel.luis@oracle.com; salil.mehta@opnsrc.net; zhukeqian
> > <zhukeqian1@huawei.com>; wangxiongfeng (C) <wangxiongfeng2@huawei.com>;
> > wangyanan (Y) <wangyanan55@huawei.com>; jiakernel2@gmail.com;
> > maobibo@loongson.cn; lixianglai@loongson.cn
> > Subject: Re: [PATCH RFC V2 31/37] physmem,gdbstub: Common helping
> > funcs/changes to *unrealize* vCPU
> >
> > Hi Salil,
> >
> > On 26/9/23 12:04, Salil Mehta wrote:
> > > Supporting vCPU Hotplug for ARM arch also means introducing new
> > functionality of
> > > unrealizing the ARMCPU. This requires some new common functions.
> > >
> > > Defining them as part of architecture independent change so that this
> > code could
> > > be reused by other interested parties.
> > >
> > > Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
> > > ---
> > > gdbstub/gdbstub.c | 13 +++++++++++++
> > > include/exec/cpu-common.h | 8 ++++++++
> > > include/exec/gdbstub.h | 1 +
> > > include/hw/core/cpu.h | 1 +
> > > softmmu/physmem.c | 25 +++++++++++++++++++++++++
> > > 5 files changed, 48 insertions(+)
> >
> >
> > > diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> > > index dab572c9bd..ffd815a0d8 100644
> > > --- a/include/hw/core/cpu.h
> > > +++ b/include/hw/core/cpu.h
> > > @@ -366,6 +366,7 @@ struct CPUState {
> > > QSIMPLEQ_HEAD(, qemu_work_item) work_list;
> > >
> > > CPUAddressSpace *cpu_ases;
> > > + int cpu_ases_ref_count;
> > > int num_ases;
> > > AddressSpace *as;
> > > MemoryRegion *memory;
> > > diff --git a/softmmu/physmem.c b/softmmu/physmem.c
> > > index 3df73542e1..a93ae783af 100644
> > > --- a/softmmu/physmem.c
> > > +++ b/softmmu/physmem.c
> > > @@ -762,6 +762,7 @@ void cpu_address_space_init(CPUState *cpu, int
> asidx,
> > >
> > > if (!cpu->cpu_ases) {
> > > cpu->cpu_ases = g_new0(CPUAddressSpace, cpu->num_ases);
> > > + cpu->cpu_ases_ref_count = cpu->num_ases;
> > > }
> > >
> > > newas = &cpu->cpu_ases[asidx];
> > > @@ -775,6 +776,30 @@ void cpu_address_space_init(CPUState *cpu, int
> > asidx,
> > > }
> > > }
> > >
> > > +void cpu_address_space_destroy(CPUState *cpu, int asidx)
> > > +{
> > > + CPUAddressSpace *cpuas;
> > > +
> > > + assert(asidx < cpu->num_ases);
> > > + assert(asidx == 0 || !kvm_enabled());
> > > + assert(cpu->cpu_ases);
> > > +
> > > + cpuas = &cpu->cpu_ases[asidx];
> > > + if (tcg_enabled()) {
> > > + memory_listener_unregister(&cpuas->tcg_as_listener);
> > > + }
> > > +
> > > + address_space_destroy(cpuas->as);
> > > + g_free_rcu(cpuas->as, rcu);
> > > +
> > > + if (cpu->cpu_ases_ref_count == 1) {
> > > + g_free(cpu->cpu_ases);
> > > + cpu->cpu_ases = NULL;
> > > + }
> > > +
> > > + cpu->cpu_ases_ref_count--;
> >
> > See Richard comment from:
> > https://lore.kernel.org/qemu-devel/594b2550-9a73-684f-6e54-
> > 29401dc6cd7a@linaro.org/
> >
> > "I think it would be better to destroy all address spaces at once,
> > "so that you don't need to invent a reference count that isn't used
> > "for anything else.
>
> Yes, we can do that and remove the reference count. The only reason I
> did it was because I was not sure if it is safe to assume that all
> the AddressSpace will always be destroyed *together*. And now since
> this is being ported to other architectures will the same hold
> true everywhere?
(sorry, I missed key point)
To make things clear further for ARM, presence of tagged/secure memory
is optional (and I am not even sure all of these are supported with
accel=KVM). The Address Space destruction function is common to all
architectures and hence it is not safe to destroy all of these together.
https://lore.kernel.org/qemu-devel/20230926100436.28284-1-salil.mehta@huawei.com/T/#mfb2a525081c412917a0026d558e72f48875e386d
+static void arm_cpu_unrealizefn(DeviceState *dev)
+{
+ ARMCPUClass *acc = ARM_CPU_GET_CLASS(dev);
+ ARMCPU *cpu = ARM_CPU(dev);
+ CPUARMState *env = &cpu->env;
+ CPUState *cs = CPU(dev);
+ bool has_secure;
+
+ has_secure = cpu->has_el3 || arm_feature(env, ARM_FEATURE_M_SECURITY);
+
+ /* rock 'n' un-roll, whatever happened in the arm_cpu_realizefn cleanly */
+ cpu_address_space_destroy(cs, ARMASIdx_NS);
+
+ if (cpu->tag_memory != NULL) {
+ cpu_address_space_destroy(cs, ARMASIdx_TagNS);
+ if (has_secure) {
+ cpu_address_space_destroy(cs, ARMASIdx_TagS);
+ }
+ }
+
+ if (has_secure) {
+ cpu_address_space_destroy(cs, ARMASIdx_S);
+ }
[...]
}
@Richard, please let me know if I understood your comment correctly?
Thanks
Salil.
next prev parent reply other threads:[~2023-10-04 9:18 UTC|newest]
Thread overview: 146+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-26 10:03 [PATCH RFC V2 00/37] Support of Virtual CPU Hotplug for ARMv8 Arch Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 01/37] arm/virt, target/arm: Add new ARMCPU {socket, cluster, core, thread}-id property Salil Mehta via
2023-09-26 23:57 ` [PATCH RFC V2 01/37] arm/virt,target/arm: Add new ARMCPU {socket,cluster,core,thread}-id property Gavin Shan
2023-10-02 9:53 ` Salil Mehta via
2023-10-02 9:53 ` Salil Mehta
2023-10-03 5:05 ` Gavin Shan
2023-09-26 10:04 ` [PATCH RFC V2 02/37] cpus-common: Add common CPU utility for possible vCPUs Salil Mehta via
2023-09-27 3:54 ` Gavin Shan
2023-10-02 10:21 ` Salil Mehta via
2023-10-02 10:21 ` Salil Mehta
2023-10-03 5:34 ` Gavin Shan
2023-09-26 10:04 ` [PATCH RFC V2 03/37] hw/arm/virt: Move setting of common CPU properties in a function Salil Mehta via
2023-09-27 5:16 ` Gavin Shan
2023-10-02 10:24 ` Salil Mehta via
2023-10-02 10:24 ` Salil Mehta
2023-10-10 6:46 ` Shaoqin Huang
2023-10-10 9:47 ` Salil Mehta via
2023-10-10 9:47 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 04/37] arm/virt, target/arm: Machine init time change common to vCPU {cold|hot}-plug Salil Mehta via
2023-09-27 6:28 ` [PATCH RFC V2 04/37] arm/virt,target/arm: " Gavin Shan
2023-10-02 16:12 ` Salil Mehta via
2023-10-02 16:12 ` Salil Mehta
2024-01-16 15:59 ` Jonathan Cameron via
2023-09-27 6:30 ` Gavin Shan
2023-10-02 10:27 ` Salil Mehta via
2023-10-02 10:27 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 05/37] accel/kvm: Extract common KVM vCPU {creation, parking} code Salil Mehta via
2023-09-27 6:51 ` [PATCH RFC V2 05/37] accel/kvm: Extract common KVM vCPU {creation,parking} code Gavin Shan
2023-10-02 16:20 ` Salil Mehta via
2023-10-02 16:20 ` Salil Mehta
2023-10-03 5:39 ` Gavin Shan
2023-09-26 10:04 ` [PATCH RFC V2 06/37] arm/virt, kvm: Pre-create disabled possible vCPUs @machine init Salil Mehta via
2023-09-27 10:04 ` [PATCH RFC V2 06/37] arm/virt,kvm: " Gavin Shan
2023-10-02 16:39 ` Salil Mehta via
2023-10-02 16:39 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 07/37] arm/virt, gicv3: Changes to pre-size GIC with possible vcpus " Salil Mehta via
2023-09-28 0:14 ` Gavin Shan
2023-10-16 16:15 ` Salil Mehta via
2023-10-16 16:15 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 08/37] arm/virt: Init PMU at host for all possible vcpus Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 09/37] hw/acpi: Move CPU ctrl-dev MMIO region len macro to common header file Salil Mehta via
2023-09-28 0:19 ` Gavin Shan
2023-10-16 16:20 ` Salil Mehta via
2023-10-16 16:20 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 10/37] arm/acpi: Enable ACPI support for vcpu hotplug Salil Mehta via
2023-09-28 0:25 ` Gavin Shan
2023-10-16 21:23 ` Salil Mehta via
2023-10-16 21:23 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 11/37] hw/acpi: Add ACPI CPU hotplug init stub Salil Mehta via
2023-09-28 0:28 ` Gavin Shan
2023-10-16 21:27 ` Salil Mehta via
2023-10-16 21:27 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 12/37] hw/acpi: Use qemu_present_cpu() API in ACPI CPU hotplug init Salil Mehta via
2023-09-28 0:40 ` Gavin Shan
2023-10-16 21:41 ` Salil Mehta via
2023-10-16 21:41 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 13/37] hw/acpi: Init GED framework with cpu hotplug events Salil Mehta via
2023-09-28 0:56 ` Gavin Shan
2023-10-16 21:44 ` Salil Mehta via
2023-10-16 21:44 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 14/37] arm/virt: Add cpu hotplug events to GED during creation Salil Mehta via
2023-09-28 1:03 ` Gavin Shan
2023-10-16 21:46 ` Salil Mehta via
2023-10-16 21:46 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 15/37] arm/virt: Create GED dev before *disabled* CPU Objs are destroyed Salil Mehta via
2023-09-28 1:08 ` Gavin Shan
2023-10-16 21:54 ` Salil Mehta via
2023-10-16 21:54 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 16/37] hw/acpi: Update CPUs AML with cpu-(ctrl)dev change Salil Mehta via
2023-09-28 1:26 ` Gavin Shan
2023-10-16 21:57 ` Salil Mehta via
2023-10-16 21:57 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 17/37] arm/virt/acpi: Build CPUs AML with CPU Hotplug support Salil Mehta via
2023-09-28 1:36 ` Gavin Shan
2023-10-16 22:05 ` Salil Mehta via
2023-10-16 22:05 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 18/37] arm/virt: Make ARM vCPU *present* status ACPI *persistent* Salil Mehta via
2023-09-28 23:18 ` Gavin Shan
2023-10-16 22:33 ` Salil Mehta via
2023-10-16 22:33 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 19/37] hw/acpi: ACPI/AML Changes to reflect the correct _STA.{PRES, ENA} Bits to Guest Salil Mehta via
2023-09-28 23:33 ` [PATCH RFC V2 19/37] hw/acpi: ACPI/AML Changes to reflect the correct _STA.{PRES,ENA} " Gavin Shan
2023-10-16 22:59 ` Salil Mehta via
2023-10-16 22:59 ` Salil Mehta
2024-01-17 21:46 ` [PATCH RFC V2 19/37] hw/acpi: ACPI/AML Changes to reflect the correct _STA.{PRES, ENA} " Jonathan Cameron via
2023-09-26 10:04 ` [PATCH RFC V2 20/37] hw/acpi: Update GED _EVT method AML with cpu scan Salil Mehta via
2023-09-28 23:35 ` Gavin Shan
2023-10-16 23:01 ` Salil Mehta via
2023-10-16 23:01 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 21/37] hw/arm: MADT Tbl change to size the guest with possible vCPUs Salil Mehta via
2023-09-28 23:43 ` Gavin Shan
2023-10-16 23:15 ` Salil Mehta via
2023-10-16 23:15 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 22/37] hw/acpi: Make _MAT method optional Salil Mehta via
2023-09-28 23:50 ` Gavin Shan
2023-10-16 23:17 ` Salil Mehta via
2023-10-16 23:17 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 23/37] arm/virt: Release objects for *disabled* possible vCPUs after init Salil Mehta via
2023-09-28 23:57 ` Gavin Shan
2023-10-16 23:28 ` Salil Mehta via
2023-10-16 23:28 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 24/37] hw/acpi: Update ACPI GED framework to support vCPU Hotplug Salil Mehta via
2023-09-26 11:02 ` Michael S. Tsirkin
2023-09-26 11:37 ` Salil Mehta via
2023-09-26 12:00 ` Michael S. Tsirkin
2023-09-26 12:27 ` Salil Mehta via
2023-09-26 13:02 ` lixianglai
2023-09-26 10:04 ` [PATCH RFC V2 25/37] arm/virt: Add/update basic hot-(un)plug framework Salil Mehta via
2023-09-29 0:20 ` Gavin Shan
2023-10-16 23:40 ` Salil Mehta via
2023-10-16 23:40 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 26/37] arm/virt: Changes to (un)wire GICC<->vCPU IRQs during hot-(un)plug Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 27/37] hw/arm, gicv3: Changes to update GIC with vCPU hot-plug notification Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 28/37] hw/intc/arm-gicv3*: Changes required to (re)init the vCPU register info Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 29/37] arm/virt: Update the guest(via GED) about CPU hot-(un)plug events Salil Mehta via
2023-09-29 0:30 ` Gavin Shan
2023-10-16 23:48 ` Salil Mehta via
2023-10-16 23:48 ` Salil Mehta
2023-09-26 10:04 ` [PATCH RFC V2 30/37] hw/arm: Changes required for reset and to support next boot Salil Mehta via
2023-09-26 10:04 ` [PATCH RFC V2 31/37] physmem, gdbstub: Common helping funcs/changes to *unrealize* vCPU Salil Mehta via
2023-10-03 6:33 ` [PATCH RFC V2 31/37] physmem,gdbstub: " Philippe Mathieu-Daudé
2023-10-03 10:22 ` Salil Mehta via
2023-10-03 10:22 ` Salil Mehta
2023-10-04 9:17 ` Salil Mehta via [this message]
2023-10-04 9:17 ` Salil Mehta
2023-09-26 10:36 ` [PATCH RFC V2 32/37] target/arm: Add support of *unrealize* ARMCPU during vCPU Hot-unplug Salil Mehta via
2023-09-26 10:36 ` [PATCH RFC V2 33/37] target/arm/kvm: Write CPU state back to KVM on reset Salil Mehta via
2023-09-26 10:36 ` [PATCH RFC V2 34/37] target/arm/kvm, tcg: Register/Handle SMCCC hypercall exits to VMM/Qemu Salil Mehta via
2023-09-29 4:15 ` [PATCH RFC V2 34/37] target/arm/kvm,tcg: " Gavin Shan
2023-10-17 0:03 ` Salil Mehta via
2023-10-17 0:03 ` Salil Mehta
2023-09-26 10:36 ` [PATCH RFC V2 35/37] hw/arm: Support hotplug capability check using _OSC method Salil Mehta via
2023-09-29 4:23 ` Gavin Shan
2023-10-17 0:13 ` Salil Mehta via
2023-10-17 0:13 ` Salil Mehta
2023-09-26 10:36 ` [PATCH RFC V2 36/37] tcg/mttcg: enable threads to unregister in tcg_ctxs[] Salil Mehta via
2023-09-26 10:36 ` [PATCH RFC V2 37/37] hw/arm/virt: Expose cold-booted CPUs as MADT GICC Enabled Salil Mehta via
2023-10-11 10:23 ` [PATCH RFC V2 00/37] Support of Virtual CPU Hotplug for ARMv8 Arch Vishnu Pajjuri
2023-10-11 10:32 ` Salil Mehta via
2023-10-11 10:32 ` Salil Mehta
2023-10-11 11:08 ` Vishnu Pajjuri
2023-10-11 20:15 ` Salil Mehta
2023-10-12 17:02 ` Miguel Luis
2023-10-12 17:54 ` Salil Mehta via
2023-10-12 17:54 ` Salil Mehta
2023-10-13 10:43 ` Miguel Luis
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