| Message ID | 20180802070201.257406-1-frankja@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v5] s390x: Enable KVM huge page backing support | expand |
On 02.08.2018 09:02, Janosch Frank wrote: > QEMU has had huge page support for a longer time already, but KVM > memory management under s390x needed some changes to work with huge > backings. > > Now that we have support, let's enable it if requested and > available. Otherwise we now properly tell the user if there is no > support and back out instead of failing to run the VM later on. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > Reviewed-by: David Hildenbrand <david@redhat.com> > --- > > Now featuring all of the required braces. > > --- > target/s390x/kvm.c | 35 +++++++++++++++++++++++++++++++++-- > 1 file changed, 33 insertions(+), 2 deletions(-) > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > index d923cf4240..8ba948c324 100644 > --- a/target/s390x/kvm.c > +++ b/target/s390x/kvm.c > @@ -34,6 +34,8 @@ > #include "qapi/error.h" > #include "qemu/error-report.h" > #include "qemu/timer.h" > +#include "qemu/units.h" > +#include "qemu/mmap-alloc.h" > #include "sysemu/sysemu.h" > #include "sysemu/hw_accel.h" > #include "hw/hw.h" > @@ -139,6 +141,7 @@ static int cap_mem_op; > static int cap_s390_irq; > static int cap_ri; > static int cap_gs; > +static int cap_hpage_1m; > > static int active_cmma; > > @@ -220,9 +223,9 @@ static void kvm_s390_enable_cmma(void) > .attr = KVM_S390_VM_MEM_ENABLE_CMMA, > }; > > - if (mem_path) { > + if (cap_hpage_1m) { > warn_report("CMM will not be enabled because it is not " > - "compatible with hugetlbfs."); > + "compatible with huge memory backings."); > return; > } > rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr); > @@ -281,10 +284,38 @@ void kvm_s390_crypto_reset(void) > } > } > > +static int kvm_s390_configure_mempath_backing(KVMState *s) > +{ > + size_t path_psize = qemu_mempath_getpagesize(mem_path); > + > + if (path_psize == 4 * KiB) { > + return 0; > + } > + > + if (path_psize != 1 * MiB) { > + error_report("Memory backing with 2G pages was specified, " > + "but KVM does not support this memory backing"); > + return -EINVAL; > + } > + > + if (kvm_vm_enable_cap(s, KVM_CAP_S390_HPAGE_1M, 0)) { > + error_report("Memory backing with 1M pages was specified, " > + "but KVM does not support this memory backing"); > + return -EINVAL; > + } > + > + cap_hpage_1m = 1; > + return 0; > +} > + > int kvm_arch_init(MachineState *ms, KVMState *s) > { > MachineClass *mc = MACHINE_GET_CLASS(ms); > > + if (mem_path && kvm_s390_configure_mempath_backing(s)) { > + return -EINVAL; > + } > + > mc->default_cpu_type = S390_CPU_TYPE_NAME("host"); > cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS); > cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF); > Looks good to me.
On 08/02/2018 09:02 AM, Janosch Frank wrote: > QEMU has had huge page support for a longer time already, but KVM > memory management under s390x needed some changes to work with huge > backings. > > Now that we have support, let's enable it if requested and > available. Otherwise we now properly tell the user if there is no > support and back out instead of failing to run the VM later on. > > Signed-off-by: Janosch Frank <frankja@linux.ibm.com> > Reviewed-by: David Hildenbrand <david@redhat.com> > --- > > Now featuring all of the required braces. > > --- > target/s390x/kvm.c | 35 +++++++++++++++++++++++++++++++++-- > 1 file changed, 33 insertions(+), 2 deletions(-) > > diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c > index d923cf4240..8ba948c324 100644 > --- a/target/s390x/kvm.c > +++ b/target/s390x/kvm.c > @@ -34,6 +34,8 @@ > #include "qapi/error.h" > #include "qemu/error-report.h" > #include "qemu/timer.h" > +#include "qemu/units.h" > +#include "qemu/mmap-alloc.h" > #include "sysemu/sysemu.h" > #include "sysemu/hw_accel.h" > #include "hw/hw.h" > @@ -139,6 +141,7 @@ static int cap_mem_op; > static int cap_s390_irq; > static int cap_ri; > static int cap_gs; > +static int cap_hpage_1m; > > static int active_cmma; > > @@ -220,9 +223,9 @@ static void kvm_s390_enable_cmma(void) > .attr = KVM_S390_VM_MEM_ENABLE_CMMA, > }; > > - if (mem_path) { > + if (cap_hpage_1m) { > warn_report("CMM will not be enabled because it is not " > - "compatible with hugetlbfs."); > + "compatible with huge memory backings."); > return; > } > rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr); > @@ -281,10 +284,38 @@ void kvm_s390_crypto_reset(void) > } > } > > +static int kvm_s390_configure_mempath_backing(KVMState *s) > +{ > + size_t path_psize = qemu_mempath_getpagesize(mem_path); > + > + if (path_psize == 4 * KiB) { > + return 0; > + } > + > + if (path_psize != 1 * MiB) { > + error_report("Memory backing with 2G pages was specified, " > + "but KVM does not support this memory backing"); > + return -EINVAL; > + } > + > + if (kvm_vm_enable_cap(s, KVM_CAP_S390_HPAGE_1M, 0)) { > + error_report("Memory backing with 1M pages was specified, " > + "but KVM does not support this memory backing"); > + return -EINVAL; > + } > + > + cap_hpage_1m = 1; > + return 0; > +} > + > int kvm_arch_init(MachineState *ms, KVMState *s) > { > MachineClass *mc = MACHINE_GET_CLASS(ms); > > + if (mem_path && kvm_s390_configure_mempath_backing(s)) { > + return -EINVAL; > + } > + > mc->default_cpu_type = S390_CPU_TYPE_NAME("host"); > cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS); > cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF); Reviewed-by: Thomas Huth <thuth@redhat.com>
diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c index d923cf4240..8ba948c324 100644 --- a/target/s390x/kvm.c +++ b/target/s390x/kvm.c @@ -34,6 +34,8 @@ #include "qapi/error.h" #include "qemu/error-report.h" #include "qemu/timer.h" +#include "qemu/units.h" +#include "qemu/mmap-alloc.h" #include "sysemu/sysemu.h" #include "sysemu/hw_accel.h" #include "hw/hw.h" @@ -139,6 +141,7 @@ static int cap_mem_op; static int cap_s390_irq; static int cap_ri; static int cap_gs; +static int cap_hpage_1m; static int active_cmma; @@ -220,9 +223,9 @@ static void kvm_s390_enable_cmma(void) .attr = KVM_S390_VM_MEM_ENABLE_CMMA, }; - if (mem_path) { + if (cap_hpage_1m) { warn_report("CMM will not be enabled because it is not " - "compatible with hugetlbfs."); + "compatible with huge memory backings."); return; } rc = kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attr); @@ -281,10 +284,38 @@ void kvm_s390_crypto_reset(void) } } +static int kvm_s390_configure_mempath_backing(KVMState *s) +{ + size_t path_psize = qemu_mempath_getpagesize(mem_path); + + if (path_psize == 4 * KiB) { + return 0; + } + + if (path_psize != 1 * MiB) { + error_report("Memory backing with 2G pages was specified, " + "but KVM does not support this memory backing"); + return -EINVAL; + } + + if (kvm_vm_enable_cap(s, KVM_CAP_S390_HPAGE_1M, 0)) { + error_report("Memory backing with 1M pages was specified, " + "but KVM does not support this memory backing"); + return -EINVAL; + } + + cap_hpage_1m = 1; + return 0; +} + int kvm_arch_init(MachineState *ms, KVMState *s) { MachineClass *mc = MACHINE_GET_CLASS(ms); + if (mem_path && kvm_s390_configure_mempath_backing(s)) { + return -EINVAL; + } + mc->default_cpu_type = S390_CPU_TYPE_NAME("host"); cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS); cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF);