Thanks for your work and let's be hopeful it gets merged soon.
regards,
Harsh
On 5/16/24 14:00, Salil Mehta wrote:
> Hi Harsh,
>
> Thanks for your interest in the patch-set but taking away patches like
> this from other series without any discussion can disrupt others work
> and its acceptance on time. This is because we will have to put lot of
> effort in rebasing bigger series and then testing overhead comes along
> with it.
>
> The patch-set (from where this patch has been taken) is part of even
> bigger series and there have been many people and companies toiling to
> fix the bugs collectively in that series and for years.
>
> I'm about float the V9 version of the Arch agnostic series which this
> patch is part of and you can rebase your patch-set from there. I'm
> hopeful that it will get accepted in this cycle.
>
>
> Many thanks
> Salil.
>
>> From: Harsh Prateek Bora <hars...@linux.ibm.com>
>> Sent: Thursday, May 16, 2024 6:32 AM
>>
>> From: Salil Mehta <salil.me...@huawei.com>
>>
>> KVM vCPU creation is done once during the vCPU realization when
Qemu
>> vCPU thread is spawned. This is common to all the architectures as of
now.
>>
>> Hot-unplug of vCPU results in destruction of the vCPU object in QOM
but
>> the corresponding KVM vCPU object in the Host KVM is not destroyed
as
>> KVM doesn't support vCPU removal. Therefore, its representative KVM
>> vCPU object/context in Qemu is parked.
>>
>> Refactor architecture common logic so that some APIs could be reused
by
>> vCPU Hotplug code of some architectures likes ARM, Loongson etc.
Update
>> new/old APIs with trace events instead of DPRINTF. No functional
change is
>> intended here.
>>
>> Signed-off-by: Salil Mehta <salil.me...@huawei.com>
>> Reviewed-by: Gavin Shan <gs...@redhat.com>
>> Tested-by: Vishnu Pajjuri <vis...@os.amperecomputing.com>
>> Reviewed-by: Jonathan Cameron <jonathan.came...@huawei.com>
>> Tested-by: Xianglai Li <lixiang...@loongson.cn>
>> Tested-by: Miguel Luis <miguel.l...@oracle.com>
>> Reviewed-by: Shaoqin Huang <shahu...@redhat.com>
>> [harshpb: fixed rebase failures in include/sysemu/kvm.h]
>> Signed-off-by: Harsh Prateek Bora <hars...@linux.ibm.com>
>> ---
>> include/sysemu/kvm.h | 15 ++++++++++
>> accel/kvm/kvm-all.c | 64 ++++++++++++++++++++++++++++++++---
-----
>> --
>> accel/kvm/trace-events | 5 +++-
>> 3 files changed, 68 insertions(+), 16 deletions(-)
>>
>> diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index
>> eaf801bc93..fa3ec74442 100644
>> --- a/include/sysemu/kvm.h
>> +++ b/include/sysemu/kvm.h
>> @@ -434,6 +434,21 @@ void kvm_set_sigmask_len(KVMState *s,
unsigned
>> int sigmask_len);
>>
>> int kvm_physical_memory_addr_from_host(KVMState *s, void
>> *ram_addr,
>> hwaddr *phys_addr);
>> +/**
>> + * kvm_create_vcpu - Gets a parked KVM vCPU or creates a KVM
vCPU
>> + * @cpu: QOM CPUState object for which KVM vCPU has to be
>> fetched/created.
>> + *
>> + * @returns: 0 when success, errno (<0) when failed.
>> + */
>> +int kvm_create_vcpu(CPUState *cpu);
>> +
>> +/**
>> + * kvm_park_vcpu - Park QEMU KVM vCPU context
>> + * @cpu: QOM CPUState object for which QEMU KVM vCPU context
has to
>> be parked.
>> + *
>> + * @returns: none
>> + */
>> +void kvm_park_vcpu(CPUState *cpu);
>>
>> #endif /* COMPILING_PER_TARGET */
>>
>> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index
>> d7281b93f3..30d42847de 100644
>> --- a/accel/kvm/kvm-all.c
>> +++ b/accel/kvm/kvm-all.c
>> @@ -128,6 +128,7 @@ static QemuMutex kml_slots_lock; #define
>> kvm_slots_unlock() qemu_mutex_unlock(&kml_slots_lock)
>>
>> static void kvm_slot_init_dirty_bitmap(KVMSlot *mem);
>> +static int kvm_get_vcpu(KVMState *s, unsigned long vcpu_id);
>>
>> static inline void kvm_resample_fd_remove(int gsi) { @@ -340,14
+341,53
>> @@ err:
>> return ret;
>> }
>>
>> +void kvm_park_vcpu(CPUState *cpu)
>> +{
>> + struct KVMParkedVcpu *vcpu;
>> +
>> + trace_kvm_park_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
>> +
>> + vcpu = g_malloc0(sizeof(*vcpu));
>> + vcpu->vcpu_id = kvm_arch_vcpu_id(cpu);
>> + vcpu->kvm_fd = cpu->kvm_fd;
>> + QLIST_INSERT_HEAD(&kvm_state->kvm_parked_vcpus, vcpu,
node); }
>> +
>> +int kvm_create_vcpu(CPUState *cpu)
>> +{
>> + unsigned long vcpu_id = kvm_arch_vcpu_id(cpu);
>> + KVMState *s = kvm_state;
>> + int kvm_fd;
>> +
>> + trace_kvm_create_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
>> +
>> + /* check if the KVM vCPU already exist but is parked */
>> + kvm_fd = kvm_get_vcpu(s, vcpu_id);
>> + if (kvm_fd < 0) {
>> + /* vCPU not parked: create a new KVM vCPU */
>> + kvm_fd = kvm_vm_ioctl(s, KVM_CREATE_VCPU, vcpu_id);
>> + if (kvm_fd < 0) {
>> + error_report("KVM_CREATE_VCPU IOCTL failed for vCPU %lu",
>> vcpu_id);
>> + return kvm_fd;
>> + }
>> + }
>> +
>> + cpu->kvm_fd = kvm_fd;
>> + cpu->kvm_state = s;
>> + cpu->vcpu_dirty = true;
>> + cpu->dirty_pages = 0;
>> + cpu->throttle_us_per_full = 0;
>> +
>> + return 0;
>> +}
>> +
>> static int do_kvm_destroy_vcpu(CPUState *cpu) {
>> KVMState *s = kvm_state;
>> long mmap_size;
>> - struct KVMParkedVcpu *vcpu = NULL;
>> int ret = 0;
>>
>> - trace_kvm_destroy_vcpu();
>> + trace_kvm_destroy_vcpu(cpu->cpu_index,
kvm_arch_vcpu_id(cpu));
>>
>> ret = kvm_arch_destroy_vcpu(cpu);
>> if (ret < 0) {
>> @@ -373,10 +413,7 @@ static int do_kvm_destroy_vcpu(CPUState
*cpu)
>> }
>> }
>>
>> - vcpu = g_malloc0(sizeof(*vcpu));
>> - vcpu->vcpu_id = kvm_arch_vcpu_id(cpu);
>> - vcpu->kvm_fd = cpu->kvm_fd;
>> - QLIST_INSERT_HEAD(&kvm_state->kvm_parked_vcpus, vcpu,
node);
>> + kvm_park_vcpu(cpu);
>> err:
>> return ret;
>> }
>> @@ -397,6 +434,8 @@ static int kvm_get_vcpu(KVMState *s, unsigned
long
>> vcpu_id)
>> if (cpu->vcpu_id == vcpu_id) {
>> int kvm_fd;
>>
>> + trace_kvm_get_vcpu(vcpu_id);
>> +
>> QLIST_REMOVE(cpu, node);
>> kvm_fd = cpu->kvm_fd;
>> g_free(cpu);
>> @@ -404,7 +443,7 @@ static int kvm_get_vcpu(KVMState *s, unsigned
long
>> vcpu_id)
>> }
>> }
>>
>> - return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id);
>> + return -ENOENT;
>> }
>>
>> int kvm_init_vcpu(CPUState *cpu, Error **errp) @@ -415,19 +454,14
@@
>> int kvm_init_vcpu(CPUState *cpu, Error **errp)
>>
>> trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
>>
>> - ret = kvm_get_vcpu(s, kvm_arch_vcpu_id(cpu));
>> + ret = kvm_create_vcpu(cpu);
>> if (ret < 0) {
>> - error_setg_errno(errp, -ret, "kvm_init_vcpu: kvm_get_vcpu failed
>> (%lu)",
>> + error_setg_errno(errp, -ret,
>> + "kvm_init_vcpu: kvm_create_vcpu failed (%lu)",
>> kvm_arch_vcpu_id(cpu));
>> goto err;
>> }
>>
>> - cpu->kvm_fd = ret;
>> - cpu->kvm_state = s;
>> - cpu->vcpu_dirty = true;
>> - cpu->dirty_pages = 0;
>> - cpu->throttle_us_per_full = 0;
>> -
>> mmap_size = kvm_ioctl(s, KVM_GET_VCPU_MMAP_SIZE, 0);
>> if (mmap_size < 0) {
>> ret = mmap_size;
>> diff --git a/accel/kvm/trace-events b/accel/kvm/trace-events index
>> 681ccb667d..75c1724e78 100644
>> --- a/accel/kvm/trace-events
>> +++ b/accel/kvm/trace-events
>> @@ -9,6 +9,10 @@ kvm_device_ioctl(int fd, int type, void *arg) "dev fd
%d,
>> type 0x%x, arg %p"
>> kvm_failed_reg_get(uint64_t id, const char *msg) "Warning: Unable to
>> retrieve ONEREG %" PRIu64 " from KVM: %s"
>> kvm_failed_reg_set(uint64_t id, const char *msg) "Warning: Unable to
set
>> ONEREG %" PRIu64 " to KVM: %s"
>> kvm_init_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d
id:
>> %lu"
>> +kvm_create_vcpu(int cpu_index, unsigned long arch_cpu_id) "index:
%d
>> id: %lu"
>> +kvm_get_vcpu(unsigned long arch_cpu_id) "id: %lu"
>> +kvm_destroy_vcpu(int cpu_index, unsigned long arch_cpu_id) "index:
%d
>> id: %lu"
>> +kvm_park_vcpu(int cpu_index, unsigned long arch_cpu_id) "index: %d
id:
>> %lu"
>> kvm_irqchip_commit_routes(void) ""
>> kvm_irqchip_add_msi_route(char *name, int vector, int virq) "dev %s
>> vector %d virq %d"
>> kvm_irqchip_update_msi_route(int virq) "Updating MSI route
virq=%d"
>> @@ -25,7 +29,6 @@ kvm_dirty_ring_reaper(const char *s) "%s"
>> kvm_dirty_ring_reap(uint64_t count, int64_t t) "reaped %"PRIu64"
pages
>> (took %"PRIi64" us)"
>> kvm_dirty_ring_reaper_kick(const char *reason) "%s"
>> kvm_dirty_ring_flush(int finished) "%d"
>> -kvm_destroy_vcpu(void) ""
>> kvm_failed_get_vcpu_mmap_size(void) ""
>> kvm_cpu_exec(void) ""
>> kvm_interrupt_exit_request(void) ""
>> --
>> 2.39.3
>
