Looks like there is a bit of noise around this recently. Do we think the hotplug patches can get over the line this time?
If not, perhaps we work with Salil to get this patch 1 upstream at least. Thanks, Nick On Tue Jun 25, 2024 at 3:08 PM AEST, Harsh Prateek Bora wrote: > +qemu-devel, qemu-ppc > > Ping! > > On 6/17/24 15:18, Harsh Prateek Bora wrote: > > > > + MST, Igor - to help with early review/merge. TIA. > > > > On 6/14/24 16:06, Salil Mehta wrote: > >> Hello > >> > >>> From: Harsh Prateek Bora <hars...@linux.ibm.com> > >>> Sent: Friday, June 14, 2024 6:24 AM > >>> Hi Paolo, Nick, > >>> Can this patch 1/8 be merged earlier provided we have got > >>> sufficient R-bys > >>> for it and the review of entire series may take a longer time? > >>> We have some ppc64 patches based on it, hence the ask. > >>> Hi Salil, > >>> I am hoping we are not expecting anymore changes to this patch, please > >>> confirm. > >> > >> > >> I do not expect any change. I had requested Michael to merge the complete > >> series as it is stranding other users. He then requested Igor to take > >> a final look but > >> he has not reverted yet. I'll remind Michael again. BTW, can you reply > >> to below > >> patch explicitly indicating your interest in the series so that MST > >> knows who else > >> are the stake holders here > >> > >> https://lore.kernel.org/qemu-devel/20240605160327.3c71f...@imammedo.users.ipa.redhat.com/ > >> > >> > >> Hi Paolo, > >> > >> A request, would it be possible to skim through this series from KVM > >> perspective? > >> (although nothing has changed which will affect the KVM and this is > >> architecture > >> agnostic patch-set) > >> > >> Many thanks! > >> > >> Best > >> Salil. > >> > >> > >>> regards, > >>> Harsh > >>> On 6/7/24 17:26, Salil Mehta wrote: > >>> > 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. 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> > >>> > Reviewed-by: Vishnu Pajjuri <vis...@os.amperecomputing.com> > >>> > Reviewed-by: Nicholas Piggin <npig...@gmail.com> > >>> > Tested-by: Zhao Liu <zhao1....@intel.com> > >>> > Reviewed-by: Zhao Liu <zhao1....@intel.com> > >>> > Reviewed-by: Harsh Prateek Bora <hars...@linux.ibm.com> > >>> > --- > >>> > accel/kvm/kvm-all.c | 95 > >>> ++++++++++++++++++++++++++++------------ > >>> -- > >>> > accel/kvm/kvm-cpus.h | 1 - > >>> > accel/kvm/trace-events | 5 ++- > >>> > include/sysemu/kvm.h | 25 +++++++++++ > >>> > 4 files changed, 92 insertions(+), 34 deletions(-) > >>> > > >>> > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index > >>> > c0be9f5eed..8f9128bb92 100644 > >>> > --- a/accel/kvm/kvm-all.c > >>> > +++ b/accel/kvm/kvm-all.c > >>> > @@ -340,14 +340,71 @@ 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_unpark_vcpu(KVMState *s, unsigned long vcpu_id) { > >>> > + struct KVMParkedVcpu *cpu; > >>> > + int kvm_fd = -ENOENT; > >>> > + > >>> > + QLIST_FOREACH(cpu, &s->kvm_parked_vcpus, node) { > >>> > + if (cpu->vcpu_id == vcpu_id) { > >>> > + QLIST_REMOVE(cpu, node); > >>> > + kvm_fd = cpu->kvm_fd; > >>> > + g_free(cpu); > >>> > + } > >>> > + } > >>> > + > >>> > + trace_kvm_unpark_vcpu(vcpu_id, kvm_fd > 0 ? "unparked" : "not > >>> > + found parked"); > >>> > + > >>> > + return kvm_fd; > >>> > +} > >>> > + > >>> > +int kvm_create_vcpu(CPUState *cpu) > >>> > +{ > >>> > + unsigned long vcpu_id = kvm_arch_vcpu_id(cpu); > >>> > + KVMState *s = kvm_state; > >>> > + int kvm_fd; > >>> > + > >>> > + /* check if the KVM vCPU already exist but is parked */ > >>> > + kvm_fd = kvm_unpark_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; > >>> > + > >>> > + trace_kvm_create_vcpu(cpu->cpu_index, vcpu_id, kvm_fd); > >>> > + > >>> > + 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 +430,7 @@ 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; > >>> > } > >>> > @@ -389,24 +443,6 @@ void kvm_destroy_vcpu(CPUState *cpu) > >>> > } > >>> > } > >>> > > >>> > -static int kvm_get_vcpu(KVMState *s, unsigned long vcpu_id) -{ > >>> > - struct KVMParkedVcpu *cpu; > >>> > - > >>> > - QLIST_FOREACH(cpu, &s->kvm_parked_vcpus, node) { > >>> > - if (cpu->vcpu_id == vcpu_id) { > >>> > - int kvm_fd; > >>> > - > >>> > - QLIST_REMOVE(cpu, node); > >>> > - kvm_fd = cpu->kvm_fd; > >>> > - g_free(cpu); > >>> > - return kvm_fd; > >>> > - } > >>> > - } > >>> > - > >>> > - return kvm_vm_ioctl(s, KVM_CREATE_VCPU, (void *)vcpu_id); > >>> > -} > >>> > - > >>> > int kvm_init_vcpu(CPUState *cpu, Error **errp) > >>> > { > >>> > KVMState *s = kvm_state; > >>> > @@ -415,19 +451,14 @@ 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/kvm-cpus.h b/accel/kvm/kvm-cpus.h index > >>> > ca40add32c..171b22fd29 100644 > >>> > --- a/accel/kvm/kvm-cpus.h > >>> > +++ b/accel/kvm/kvm-cpus.h > >>> > @@ -22,5 +22,4 @@ bool kvm_supports_guest_debug(void); > >>> > int kvm_insert_breakpoint(CPUState *cpu, int type, vaddr addr, > >>> vaddr > >>> len); > >>> > int kvm_remove_breakpoint(CPUState *cpu, int type, vaddr addr, > >>> vaddr > >>> len); > >>> > void kvm_remove_all_breakpoints(CPUState *cpu); > >>> > - > >>> > #endif /* KVM_CPUS_H */ > >>> > diff --git a/accel/kvm/trace-events b/accel/kvm/trace-events index > >>> > 681ccb667d..37626c1ac5 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, int > >>> kvm_fd) "index: %d, id: %lu, kvm fd: %d" > >>> > +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_unpark_vcpu(unsigned long arch_cpu_id, const char *msg) "id: > >>> %lu > >>> %s" > >>> > 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) "" > >>> > diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index > >>> > c31d9c7356..c4a914b3d8 100644 > >>> > --- a/include/sysemu/kvm.h > >>> > +++ b/include/sysemu/kvm.h > >>> > @@ -313,6 +313,31 @@ int kvm_create_device(KVMState *s, uint64_t > >>> type, bool test); > >>> > */ > >>> > bool kvm_device_supported(int vmfd, uint64_t type); > >>> > > >>> > +/** > >>> > + * 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); > >>> > + > >>> > +/** > >>> > + * kvm_unpark_vcpu - unpark QEMU KVM vCPU context > >>> > + * @s: KVM State > >>> > + * @vcpu_id: Architecture vCPU ID of the parked vCPU > >>> > + * > >>> > + * @returns: KVM fd > >>> > + */ > >>> > +int kvm_unpark_vcpu(KVMState *s, unsigned long vcpu_id); > >>> > + > >>> > /* Arch specific hooks */ > >>> > > >>> > extern const KVMCapabilityInfo kvm_arch_required_capabilities[];
