| Message ID | 20230201132051.126868-3-pmorel@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | s390x: CPU Topology | expand |
On Wed, 2023-02-01 at 14:20 +0100, Pierre Morel wrote: > The topology information are attributes of the CPU and are > specified during the CPU device creation. > > On hot plug we: > - calculate the default values for the topology for drawers, > books and sockets in the case they are not specified. > - verify the CPU attributes > - check that we have still room on the desired socket > > The possibility to insert a CPU in a mask is dependent on the > number of cores allowed in a socket, a book or a drawer, the > checking is done during the hot plug of the CPU to have an > immediate answer. > > If the complete topology is not specified, the core is added > in the physical topology based on its core ID and it gets > defaults values for the modifier attributes. > > This way, starting QEMU without specifying the topology can > still get some advantage of the CPU topology. > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > --- > include/hw/s390x/cpu-topology.h | 24 +++ > hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ > hw/s390x/s390-virtio-ccw.c | 23 ++- > hw/s390x/meson.build | 1 + > 4 files changed, 302 insertions(+), 2 deletions(-) > create mode 100644 hw/s390x/cpu-topology.c > [...] > > diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c > new file mode 100644 > index 0000000000..12df4eca6c > --- /dev/null > +++ b/hw/s390x/cpu-topology.c > @@ -0,0 +1,256 @@ > +/* > + * CPU Topology > + * > + * Copyright IBM Corp. 2022 > + * Author(s): Pierre Morel <pmorel@linux.ibm.com> > + > + * This work is licensed under the terms of the GNU GPL, version 2 or (at > + * your option) any later version. See the COPYING file in the top-level > + * directory. > + */ > + > +#include "qemu/osdep.h" > +#include "qapi/error.h" > +#include "qemu/error-report.h" > +#include "hw/qdev-properties.h" > +#include "hw/boards.h" > +#include "qemu/typedefs.h" > +#include "target/s390x/cpu.h" > +#include "hw/s390x/s390-virtio-ccw.h" > +#include "hw/s390x/cpu-topology.h" > + > +/* > + * s390_topology is used to keep the topology information. > + * .list: queue the topology entries inside which > + * we keep the information on the CPU topology. .list doesn't exist yet. > + * .socket: tracks information on the count of cores per socket. > + * .smp: keeps track of the machine topology. > + * > + */ > +S390Topology s390_topology = { > + /* will be initialized after the cpu model is realized */ > + .cores_per_socket = NULL, > + .smp = NULL, > +}; > [...] > + > +/** > + * s390_topology_cpu_default: > + * @cpu: pointer to a S390CPU > + * @errp: Error pointer > + * > + * Setup the default topology for unset attributes. My suggestion: Setup the default topology if no attributes are already set. Passing a CPU with some, but not all, attributes set is considered an error. > + * > + * The function accept only all all default values or all set values > + * for the geometry topology. acceptS, all all If you take my suggestion, you can just drop this sentence. > + * > + * The function calculates the (drawer_id, book_id, socket_id) > + * topology by filling the cores starting from the first socket > + * (0, 0, 0) up to the last (smp->drawers, smp->books, smp->sockets). > + * > + * CPU type, polarity and dedication have defaults values set in the > + * s390x_cpu_properties. > + */ > +static void s390_topology_cpu_default(S390CPU *cpu, Error **errp) > +{ > + CpuTopology *smp = s390_topology.smp; > + CPUS390XState *env = &cpu->env; > + > + /* All geometry topology attributes must be set or all unset */ > + if ((env->socket_id < 0 || env->book_id < 0 || env->drawer_id < 0) && > + (env->socket_id >= 0 || env->book_id >= 0 || env->drawer_id >= 0)) { > + error_setg(errp, > + "Please define all or none of the topology geometry attributes"); > + return; > + } > + > + /* Check if one of the geometry topology is unset */ > + if (env->socket_id < 0) { > + /* Calculate default geometry topology attributes */ > + env->socket_id = (env->core_id / smp->cores) % smp->sockets; > + env->book_id = (env->core_id / (smp->sockets * smp->cores)) % > + smp->books; > + env->drawer_id = (env->core_id / > + (smp->books * smp->sockets * smp->cores)) % > + smp->drawers; > + } > +} > [...] > + > +/** > + * s390_set_core_in_socket: > + * @cpu: the new S390CPU to insert in the topology structure > + * @drawer_id: new drawer_id > + * @book_id: new book_id > + * @socket_id: new socket_id > + * @creation: if is true the CPU is a new CPU and there is no old socket > + * to handle. > + * if is false, this is a moving the CPU and old socket count > + * must be decremented. > + * @errp: the error pointer > + * > + */ > +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, Maybe name it s390_(topology_)?add_core_to_socket instead. > + int socket_id, bool creation, Error **errp) > +{ > + int old_socket = s390_socket_nb(cpu); > + int new_socket; > + > + if (creation) { > + new_socket = old_socket; > + } else { You need parentheses here. > + new_socket = drawer_id * s390_topology.smp->books + ( > + book_id * s390_topology.smp->sockets + ) > + socket_id; > + } > + > + /* Check for space on new socket */ > + if ((new_socket != old_socket) && > + (s390_topology.cores_per_socket[new_socket] >= > + s390_topology.smp->cores)) { > + error_setg(errp, "No more space on this socket"); > + return; > + } > + > + /* Update the count of cores in sockets */ > + s390_topology.cores_per_socket[new_socket] += 1; > + if (!creation) { > + s390_topology.cores_per_socket[old_socket] -= 1; > + } > +} > [...] > +/** > + * s390_topology_set_cpu: > + * @ms: MachineState used to initialize the topology structure on > + * first call. > + * @cpu: the new S390CPU to insert in the topology structure > + * @errp: the error pointer > + * > + * Called from CPU Hotplug to check and setup the CPU attributes > + * before to insert the CPU in the topology. > + */ > +void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp) The name is rather non informative. s390_topology_setup_cpu ? > +{ > + ERRP_GUARD(); > + > + /* > + * We do not want to initialize the topology if the cpu model > + * does not support topology consequently, we have to wait for ^ Still think there should be a comma here. > + * the first CPU to be realized, which realizes the CPU model > + * to initialize the topology structures. > + * > + * s390_topology_set_cpu() is called from the cpu hotplug. > + */ > + if (!s390_topology.cores_per_socket) { > + s390_topology_init(ms); > + } > + > + s390_topology_check(cpu, errp); > + if (*errp) { > + return; > + } > + > + /* Set the CPU inside the socket */ > + s390_set_core_in_socket(cpu, 0, 0, 0, true, errp); > + if (*errp) { > + return; > + } > + > + /* topology tree is reflected in props */ > + s390_update_cpu_props(ms, cpu); > +} > diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c > index f3cc845d3b..9bc51a83f4 100644 > --- a/hw/s390x/s390-virtio-ccw.c > +++ b/hw/s390x/s390-virtio-ccw.c > @@ -44,6 +44,7 @@ > #include "hw/s390x/pv.h" > #include "migration/blocker.h" > #include "qapi/visitor.h" > +#include "hw/s390x/cpu-topology.h" > > static Error *pv_mig_blocker; > > @@ -310,10 +311,18 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev, > { > MachineState *ms = MACHINE(hotplug_dev); > S390CPU *cpu = S390_CPU(dev); > + ERRP_GUARD(); > > g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu); > ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev); > > + if (s390_has_topology()) { > + s390_topology_set_cpu(ms, cpu, errp); > + if (*errp) { > + return; > + } > + } > + > if (dev->hotplugged) { > raise_irq_cpu_hotplug(); > } > @@ -551,11 +560,21 @@ static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms) > sizeof(CPUArchId) * max_cpus); > ms->possible_cpus->len = max_cpus; > for (i = 0; i < ms->possible_cpus->len; i++) { > + CpuInstanceProperties *props = &ms->possible_cpus->cpus[i].props; > + > ms->possible_cpus->cpus[i].type = ms->cpu_type; > ms->possible_cpus->cpus[i].vcpus_count = 1; > ms->possible_cpus->cpus[i].arch_id = i; > - ms->possible_cpus->cpus[i].props.has_core_id = true; > - ms->possible_cpus->cpus[i].props.core_id = i; > + > + props->has_core_id = true; > + props->core_id = i; > + props->has_socket_id = true; > + props->socket_id = i / ms->smp.cores; > + props->has_book_id = true; > + props->book_id = i / (ms->smp.cores * ms->smp.sockets); > + props->has_drawer_id = true; > + props->drawer_id = i / > + (ms->smp.cores * ms->smp.sockets * ms->smp.books); You need to calculate the modulus like in s390_topology_cpu_default, right? > } > > return ms->possible_cpus; > diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build > index f291016fee..58dfbdff4f 100644 > --- a/hw/s390x/meson.build > +++ b/hw/s390x/meson.build > @@ -24,6 +24,7 @@ s390x_ss.add(when: 'CONFIG_KVM', if_true: files( > 's390-stattrib-kvm.c', > 'pv.c', > 's390-pci-kvm.c', > + 'cpu-topology.c', > )) > s390x_ss.add(when: 'CONFIG_TCG', if_true: files( > 'tod-tcg.c',
On 2/2/23 17:42, Nina Schoetterl-Glausch wrote: > On Wed, 2023-02-01 at 14:20 +0100, Pierre Morel wrote: >> The topology information are attributes of the CPU and are >> specified during the CPU device creation. >> >> On hot plug we: >> - calculate the default values for the topology for drawers, >> books and sockets in the case they are not specified. >> - verify the CPU attributes >> - check that we have still room on the desired socket >> >> The possibility to insert a CPU in a mask is dependent on the >> number of cores allowed in a socket, a book or a drawer, the >> checking is done during the hot plug of the CPU to have an >> immediate answer. >> >> If the complete topology is not specified, the core is added >> in the physical topology based on its core ID and it gets >> defaults values for the modifier attributes. >> >> This way, starting QEMU without specifying the topology can >> still get some advantage of the CPU topology. >> >> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >> --- >> include/hw/s390x/cpu-topology.h | 24 +++ >> hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ >> hw/s390x/s390-virtio-ccw.c | 23 ++- >> hw/s390x/meson.build | 1 + >> 4 files changed, 302 insertions(+), 2 deletions(-) >> create mode 100644 hw/s390x/cpu-topology.c >> > [...] >> >> diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c >> new file mode 100644 >> index 0000000000..12df4eca6c >> --- /dev/null >> +++ b/hw/s390x/cpu-topology.c >> @@ -0,0 +1,256 @@ >> +/* >> + * CPU Topology >> + * >> + * Copyright IBM Corp. 2022 >> + * Author(s): Pierre Morel <pmorel@linux.ibm.com> >> + >> + * This work is licensed under the terms of the GNU GPL, version 2 or (at >> + * your option) any later version. See the COPYING file in the top-level >> + * directory. >> + */ >> + >> +#include "qemu/osdep.h" >> +#include "qapi/error.h" >> +#include "qemu/error-report.h" >> +#include "hw/qdev-properties.h" >> +#include "hw/boards.h" >> +#include "qemu/typedefs.h" >> +#include "target/s390x/cpu.h" >> +#include "hw/s390x/s390-virtio-ccw.h" >> +#include "hw/s390x/cpu-topology.h" >> + >> +/* >> + * s390_topology is used to keep the topology information. >> + * .list: queue the topology entries inside which >> + * we keep the information on the CPU topology. > > .list doesn't exist yet. right, I move it to the corresponding patch. > >> + * .socket: tracks information on the count of cores per socket. >> + * .smp: keeps track of the machine topology. >> + * >> + */ >> +S390Topology s390_topology = { >> + /* will be initialized after the cpu model is realized */ >> + .cores_per_socket = NULL, >> + .smp = NULL, >> +}; >> > [...] >> + >> +/** >> + * s390_topology_cpu_default: >> + * @cpu: pointer to a S390CPU >> + * @errp: Error pointer >> + * >> + * Setup the default topology for unset attributes. > > My suggestion: > Setup the default topology if no attributes are already set. > Passing a CPU with some, but not all, attributes set is considered an error. Thanks, I take your suggestion. > >> + * >> + * The function accept only all all default values or all set values >> + * for the geometry topology. > > acceptS, all all > If you take my suggestion, you can just drop this sentence. > >> + * >> + * The function calculates the (drawer_id, book_id, socket_id) >> + * topology by filling the cores starting from the first socket >> + * (0, 0, 0) up to the last (smp->drawers, smp->books, smp->sockets). >> + * >> + * CPU type, polarity and dedication have defaults values set in the >> + * s390x_cpu_properties. >> + */ >> +static void s390_topology_cpu_default(S390CPU *cpu, Error **errp) >> +{ >> + CpuTopology *smp = s390_topology.smp; >> + CPUS390XState *env = &cpu->env; >> + >> + /* All geometry topology attributes must be set or all unset */ >> + if ((env->socket_id < 0 || env->book_id < 0 || env->drawer_id < 0) && >> + (env->socket_id >= 0 || env->book_id >= 0 || env->drawer_id >= 0)) { >> + error_setg(errp, >> + "Please define all or none of the topology geometry attributes"); >> + return; >> + } >> + >> + /* Check if one of the geometry topology is unset */ >> + if (env->socket_id < 0) { >> + /* Calculate default geometry topology attributes */ >> + env->socket_id = (env->core_id / smp->cores) % smp->sockets; >> + env->book_id = (env->core_id / (smp->sockets * smp->cores)) % >> + smp->books; >> + env->drawer_id = (env->core_id / >> + (smp->books * smp->sockets * smp->cores)) % >> + smp->drawers; >> + } >> +} >> > [...] >> + >> +/** >> + * s390_set_core_in_socket: >> + * @cpu: the new S390CPU to insert in the topology structure >> + * @drawer_id: new drawer_id >> + * @book_id: new book_id >> + * @socket_id: new socket_id >> + * @creation: if is true the CPU is a new CPU and there is no old socket >> + * to handle. >> + * if is false, this is a moving the CPU and old socket count >> + * must be decremented. >> + * @errp: the error pointer >> + * >> + */ >> +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, > > Maybe name it s390_(topology_)?add_core_to_socket instead. OK, it is better > >> + int socket_id, bool creation, Error **errp) >> +{ >> + int old_socket = s390_socket_nb(cpu); >> + int new_socket; >> + >> + if (creation) { >> + new_socket = old_socket; >> + } else { > > You need parentheses here. > >> + new_socket = drawer_id * s390_topology.smp->books + > ( >> + book_id * s390_topology.smp->sockets + > ) >> + socket_id; If you prefer I can us parentheses. >> + } >> + >> + /* Check for space on new socket */ >> + if ((new_socket != old_socket) && >> + (s390_topology.cores_per_socket[new_socket] >= >> + s390_topology.smp->cores)) { >> + error_setg(errp, "No more space on this socket"); >> + return; >> + } >> + >> + /* Update the count of cores in sockets */ >> + s390_topology.cores_per_socket[new_socket] += 1; >> + if (!creation) { >> + s390_topology.cores_per_socket[old_socket] -= 1; >> + } >> +} >> > [...] > >> +/** >> + * s390_topology_set_cpu: >> + * @ms: MachineState used to initialize the topology structure on >> + * first call. >> + * @cpu: the new S390CPU to insert in the topology structure >> + * @errp: the error pointer >> + * >> + * Called from CPU Hotplug to check and setup the CPU attributes >> + * before to insert the CPU in the topology. >> + */ >> +void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp) > > The name is rather non informative. > s390_topology_setup_cpu ? OK > >> +{ >> + ERRP_GUARD(); >> + >> + /* >> + * We do not want to initialize the topology if the cpu model >> + * does not support topology consequently, we have to wait for > ^ > Still think there should be a comma here. OK > >> + * the first CPU to be realized, which realizes the CPU model >> + * to initialize the topology structures. >> + * >> + * s390_topology_set_cpu() is called from the cpu hotplug. >> + */ >> + if (!s390_topology.cores_per_socket) { >> + s390_topology_init(ms); >> + } >> + >> + s390_topology_check(cpu, errp); >> + if (*errp) { >> + return; >> + } >> + >> + /* Set the CPU inside the socket */ >> + s390_set_core_in_socket(cpu, 0, 0, 0, true, errp); >> + if (*errp) { >> + return; >> + } >> + >> + /* topology tree is reflected in props */ >> + s390_update_cpu_props(ms, cpu); >> +} >> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c >> index f3cc845d3b..9bc51a83f4 100644 >> --- a/hw/s390x/s390-virtio-ccw.c >> +++ b/hw/s390x/s390-virtio-ccw.c >> @@ -44,6 +44,7 @@ >> #include "hw/s390x/pv.h" >> #include "migration/blocker.h" >> #include "qapi/visitor.h" >> +#include "hw/s390x/cpu-topology.h" >> >> static Error *pv_mig_blocker; >> >> @@ -310,10 +311,18 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev, >> { >> MachineState *ms = MACHINE(hotplug_dev); >> S390CPU *cpu = S390_CPU(dev); >> + ERRP_GUARD(); >> >> g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu); >> ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev); >> >> + if (s390_has_topology()) { >> + s390_topology_set_cpu(ms, cpu, errp); >> + if (*errp) { >> + return; >> + } >> + } >> + >> if (dev->hotplugged) { >> raise_irq_cpu_hotplug(); >> } >> @@ -551,11 +560,21 @@ static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms) >> sizeof(CPUArchId) * max_cpus); >> ms->possible_cpus->len = max_cpus; >> for (i = 0; i < ms->possible_cpus->len; i++) { >> + CpuInstanceProperties *props = &ms->possible_cpus->cpus[i].props; >> + >> ms->possible_cpus->cpus[i].type = ms->cpu_type; >> ms->possible_cpus->cpus[i].vcpus_count = 1; >> ms->possible_cpus->cpus[i].arch_id = i; >> - ms->possible_cpus->cpus[i].props.has_core_id = true; >> - ms->possible_cpus->cpus[i].props.core_id = i; >> + >> + props->has_core_id = true; >> + props->core_id = i; >> + props->has_socket_id = true; >> + props->socket_id = i / ms->smp.cores; >> + props->has_book_id = true; >> + props->book_id = i / (ms->smp.cores * ms->smp.sockets); >> + props->has_drawer_id = true; >> + props->drawer_id = i / >> + (ms->smp.cores * ms->smp.sockets * ms->smp.books); > > You need to calculate the modulus like in s390_topology_cpu_default, right? !!! yes of course, good catch, I forgot that. Since there are two uses of this calculation, what about using inlines? like: static inline int s390_std_socket(int n, CpuTopology *smp) { return (n / smp->cores) % smp->sockets; } static inline int s390_std_book(int n, CpuTopology *smp) { return (n / (smp->cores * smp->sockets)) % smp->books; } static inline int s390_std_drawer(int n, CpuTopology *smp) { return (n / (smp->cores * smp->sockets * smp->books)) % smp->books; } Thanks for the comments. Regards, Pierre
On Fri, 2023-02-03 at 10:21 +0100, Pierre Morel wrote: > > On 2/2/23 17:42, Nina Schoetterl-Glausch wrote: > > On Wed, 2023-02-01 at 14:20 +0100, Pierre Morel wrote: > > > The topology information are attributes of the CPU and are > > > specified during the CPU device creation. > > > > > > On hot plug we: > > > - calculate the default values for the topology for drawers, > > > books and sockets in the case they are not specified. > > > - verify the CPU attributes > > > - check that we have still room on the desired socket > > > > > > The possibility to insert a CPU in a mask is dependent on the > > > number of cores allowed in a socket, a book or a drawer, the > > > checking is done during the hot plug of the CPU to have an > > > immediate answer. > > > > > > If the complete topology is not specified, the core is added > > > in the physical topology based on its core ID and it gets > > > defaults values for the modifier attributes. > > > > > > This way, starting QEMU without specifying the topology can > > > still get some advantage of the CPU topology. > > > > > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > > > --- > > > include/hw/s390x/cpu-topology.h | 24 +++ > > > hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ > > > hw/s390x/s390-virtio-ccw.c | 23 ++- > > > hw/s390x/meson.build | 1 + > > > 4 files changed, 302 insertions(+), 2 deletions(-) > > > create mode 100644 hw/s390x/cpu-topology.c > > > [...] > > > > > +/** > > > + * s390_set_core_in_socket: > > > + * @cpu: the new S390CPU to insert in the topology structure > > > + * @drawer_id: new drawer_id > > > + * @book_id: new book_id > > > + * @socket_id: new socket_id > > > + * @creation: if is true the CPU is a new CPU and there is no old socket > > > + * to handle. > > > + * if is false, this is a moving the CPU and old socket count > > > + * must be decremented. > > > + * @errp: the error pointer > > > + * > > > + */ > > > +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, > > > > Maybe name it s390_(topology_)?add_core_to_socket instead. > > OK, it is better > > > > > > + int socket_id, bool creation, Error **errp) > > > +{ > > > + int old_socket = s390_socket_nb(cpu); > > > + int new_socket; > > > + > > > + if (creation) { > > > + new_socket = old_socket; > > > + } else { > > > > You need parentheses here. > > > > > + new_socket = drawer_id * s390_topology.smp->books + > > ( > > > + book_id * s390_topology.smp->sockets + > > ) > > > + socket_id; > > If you prefer I can us parentheses. It's necessary, otherwise the multiplication of book_id and smp->sockets takes precedence. > > > > > + } > > > + > > > + /* Check for space on new socket */ > > > + if ((new_socket != old_socket) && > > > + (s390_topology.cores_per_socket[new_socket] >= > > > + s390_topology.smp->cores)) { > > > + error_setg(errp, "No more space on this socket"); > > > + return; > > > + } > > > + > > > + /* Update the count of cores in sockets */ > > > + s390_topology.cores_per_socket[new_socket] += 1; > > > + if (!creation) { > > > + s390_topology.cores_per_socket[old_socket] -= 1; > > > + } > > > +} > > > [...] > > > > > diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c > > > index f3cc845d3b..9bc51a83f4 100644 > > > --- a/hw/s390x/s390-virtio-ccw.c > > > +++ b/hw/s390x/s390-virtio-ccw.c > > > @@ -44,6 +44,7 @@ > > > #include "hw/s390x/pv.h" > > > #include "migration/blocker.h" > > > #include "qapi/visitor.h" > > > +#include "hw/s390x/cpu-topology.h" > > > > > > static Error *pv_mig_blocker; > > > > > > @@ -310,10 +311,18 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev, > > > { > > > MachineState *ms = MACHINE(hotplug_dev); > > > S390CPU *cpu = S390_CPU(dev); > > > + ERRP_GUARD(); > > > > > > g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu); > > > ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev); > > > > > > + if (s390_has_topology()) { > > > + s390_topology_set_cpu(ms, cpu, errp); > > > + if (*errp) { > > > + return; > > > + } > > > + } > > > + > > > if (dev->hotplugged) { > > > raise_irq_cpu_hotplug(); > > > } > > > @@ -551,11 +560,21 @@ static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms) > > > sizeof(CPUArchId) * max_cpus); > > > ms->possible_cpus->len = max_cpus; > > > for (i = 0; i < ms->possible_cpus->len; i++) { > > > + CpuInstanceProperties *props = &ms->possible_cpus->cpus[i].props; > > > + > > > ms->possible_cpus->cpus[i].type = ms->cpu_type; > > > ms->possible_cpus->cpus[i].vcpus_count = 1; > > > ms->possible_cpus->cpus[i].arch_id = i; > > > - ms->possible_cpus->cpus[i].props.has_core_id = true; > > > - ms->possible_cpus->cpus[i].props.core_id = i; > > > + > > > + props->has_core_id = true; > > > + props->core_id = i; > > > + props->has_socket_id = true; > > > + props->socket_id = i / ms->smp.cores; > > > + props->has_book_id = true; > > > + props->book_id = i / (ms->smp.cores * ms->smp.sockets); > > > + props->has_drawer_id = true; > > > + props->drawer_id = i / > > > + (ms->smp.cores * ms->smp.sockets * ms->smp.books); > > > > You need to calculate the modulus like in s390_topology_cpu_default, right? > > !!! yes of course, good catch, I forgot that. > > Since there are two uses of this calculation, what about using inlines? > like: Fine by me, I just have no idea what std is short for. Since this would be used in s390_topology_cpu_default and calculates the default assignment, I would call it s390_topology_cpu_default_socket, book, etc. or similar > > static inline int s390_std_socket(int n, CpuTopology *smp) > { > return (n / smp->cores) % smp->sockets; > } > > static inline int s390_std_book(int n, CpuTopology *smp) > { > return (n / (smp->cores * smp->sockets)) % smp->books; > } > > static inline int s390_std_drawer(int n, CpuTopology *smp) > { > return (n / (smp->cores * smp->sockets * smp->books)) % smp->books; > } > > > Thanks for the comments. > > Regards, > Pierre >
On 2/3/23 14:22, Nina Schoetterl-Glausch wrote: > On Fri, 2023-02-03 at 10:21 +0100, Pierre Morel wrote: >> >> On 2/2/23 17:42, Nina Schoetterl-Glausch wrote: >>> On Wed, 2023-02-01 at 14:20 +0100, Pierre Morel wrote: >>>> The topology information are attributes of the CPU and are >>>> specified during the CPU device creation. >>>> >>>> On hot plug we: >>>> - calculate the default values for the topology for drawers, >>>> books and sockets in the case they are not specified. >>>> - verify the CPU attributes >>>> - check that we have still room on the desired socket >>>> >>>> The possibility to insert a CPU in a mask is dependent on the >>>> number of cores allowed in a socket, a book or a drawer, the >>>> checking is done during the hot plug of the CPU to have an >>>> immediate answer. >>>> >>>> If the complete topology is not specified, the core is added >>>> in the physical topology based on its core ID and it gets >>>> defaults values for the modifier attributes. >>>> >>>> This way, starting QEMU without specifying the topology can >>>> still get some advantage of the CPU topology. >>>> >>>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >>>> --- >>>> include/hw/s390x/cpu-topology.h | 24 +++ >>>> hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ >>>> hw/s390x/s390-virtio-ccw.c | 23 ++- >>>> hw/s390x/meson.build | 1 + >>>> 4 files changed, 302 insertions(+), 2 deletions(-) >>>> create mode 100644 hw/s390x/cpu-topology.c >>>> > [...] >>> >>>> +/** >>>> + * s390_set_core_in_socket: >>>> + * @cpu: the new S390CPU to insert in the topology structure >>>> + * @drawer_id: new drawer_id >>>> + * @book_id: new book_id >>>> + * @socket_id: new socket_id >>>> + * @creation: if is true the CPU is a new CPU and there is no old socket >>>> + * to handle. >>>> + * if is false, this is a moving the CPU and old socket count >>>> + * must be decremented. >>>> + * @errp: the error pointer >>>> + * >>>> + */ >>>> +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, >>> >>> Maybe name it s390_(topology_)?add_core_to_socket instead. >> >> OK, it is better >> >>> >>>> + int socket_id, bool creation, Error **errp) >>>> +{ >>>> + int old_socket = s390_socket_nb(cpu); >>>> + int new_socket; >>>> + >>>> + if (creation) { >>>> + new_socket = old_socket; >>>> + } else { >>> >>> You need parentheses here. >>> >>>> + new_socket = drawer_id * s390_topology.smp->books + >>> ( >>>> + book_id * s390_topology.smp->sockets + >>> ) >>>> + socket_id; >> >> If you prefer I can us parentheses. > > It's necessary, otherwise the multiplication of book_id and smp->sockets takes precedence. >> >> Right, I did not understand where you want the parenthesis. I think you mean: new_socket = (drawer_id * s390_topology.smp->books + book_id) * s390_topology.smp->sockets + socket_id; thanks, Regards, Pierre
On Fri, 2023-02-03 at 15:40 +0100, Pierre Morel wrote: > > On 2/3/23 14:22, Nina Schoetterl-Glausch wrote: > > On Fri, 2023-02-03 at 10:21 +0100, Pierre Morel wrote: > > > > > > On 2/2/23 17:42, Nina Schoetterl-Glausch wrote: > > > > On Wed, 2023-02-01 at 14:20 +0100, Pierre Morel wrote: > > > > > The topology information are attributes of the CPU and are > > > > > specified during the CPU device creation. > > > > > > > > > > On hot plug we: > > > > > - calculate the default values for the topology for drawers, > > > > > books and sockets in the case they are not specified. > > > > > - verify the CPU attributes > > > > > - check that we have still room on the desired socket > > > > > > > > > > The possibility to insert a CPU in a mask is dependent on the > > > > > number of cores allowed in a socket, a book or a drawer, the > > > > > checking is done during the hot plug of the CPU to have an > > > > > immediate answer. > > > > > > > > > > If the complete topology is not specified, the core is added > > > > > in the physical topology based on its core ID and it gets > > > > > defaults values for the modifier attributes. > > > > > > > > > > This way, starting QEMU without specifying the topology can > > > > > still get some advantage of the CPU topology. > > > > > > > > > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > > > > > --- > > > > > include/hw/s390x/cpu-topology.h | 24 +++ > > > > > hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ > > > > > hw/s390x/s390-virtio-ccw.c | 23 ++- > > > > > hw/s390x/meson.build | 1 + > > > > > 4 files changed, 302 insertions(+), 2 deletions(-) > > > > > create mode 100644 hw/s390x/cpu-topology.c > > > > > > > [...] > > > > > > > > > +/** > > > > > + * s390_set_core_in_socket: > > > > > + * @cpu: the new S390CPU to insert in the topology structure > > > > > + * @drawer_id: new drawer_id > > > > > + * @book_id: new book_id > > > > > + * @socket_id: new socket_id > > > > > + * @creation: if is true the CPU is a new CPU and there is no old socket > > > > > + * to handle. > > > > > + * if is false, this is a moving the CPU and old socket count > > > > > + * must be decremented. > > > > > + * @errp: the error pointer > > > > > + * > > > > > + */ > > > > > +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, > > > > > > > > Maybe name it s390_(topology_)?add_core_to_socket instead. > > > > > > OK, it is better > > > > > > > > > > > > + int socket_id, bool creation, Error **errp) > > > > > +{ > > > > > + int old_socket = s390_socket_nb(cpu); > > > > > + int new_socket; > > > > > + > > > > > + if (creation) { > > > > > + new_socket = old_socket; > > > > > + } else { > > > > > > > > You need parentheses here. > > > > > > > > > + new_socket = drawer_id * s390_topology.smp->books + > > > > ( > > > > > + book_id * s390_topology.smp->sockets + > > > > ) > > > > > + socket_id; > > > > > > If you prefer I can us parentheses. > > > > It's necessary, otherwise the multiplication of book_id and smp->sockets takes precedence. > > > > > > > > Right, I did not understand where you want the parenthesis. > I think you mean: > > new_socket = (drawer_id * s390_topology.smp->books + book_id) * > s390_topology.smp->sockets + socket_id; Yes, exactly. I see how it was ambiguous. > > thanks, > > Regards, > Pierre >
diff --git a/include/hw/s390x/cpu-topology.h b/include/hw/s390x/cpu-topology.h index 7a84b30a21..9b6f889ad4 100644 --- a/include/hw/s390x/cpu-topology.h +++ b/include/hw/s390x/cpu-topology.h @@ -10,6 +10,9 @@ #ifndef HW_S390X_CPU_TOPOLOGY_H #define HW_S390X_CPU_TOPOLOGY_H +#include "qemu/queue.h" +#include "hw/boards.h" + #define S390_TOPOLOGY_CPU_IFL 0x03 enum s390_topology_polarity { @@ -21,4 +24,25 @@ enum s390_topology_polarity { POLARITY_MAX, }; +typedef struct S390Topology { + uint8_t *cores_per_socket; + CpuTopology *smp; +} S390Topology; + +#ifdef CONFIG_KVM +bool s390_has_topology(void); +void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp); +#else +static inline bool s390_has_topology(void) +{ + return false; +} +static inline void s390_topology_set_cpu(MachineState *ms, + S390CPU *cpu, + Error **errp) {} +#endif + +extern S390Topology s390_topology; +int s390_socket_nb(S390CPU *cpu); + #endif diff --git a/hw/s390x/cpu-topology.c b/hw/s390x/cpu-topology.c new file mode 100644 index 0000000000..12df4eca6c --- /dev/null +++ b/hw/s390x/cpu-topology.c @@ -0,0 +1,256 @@ +/* + * CPU Topology + * + * Copyright IBM Corp. 2022 + * Author(s): Pierre Morel <pmorel@linux.ibm.com> + + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/error-report.h" +#include "hw/qdev-properties.h" +#include "hw/boards.h" +#include "qemu/typedefs.h" +#include "target/s390x/cpu.h" +#include "hw/s390x/s390-virtio-ccw.h" +#include "hw/s390x/cpu-topology.h" + +/* + * s390_topology is used to keep the topology information. + * .list: queue the topology entries inside which + * we keep the information on the CPU topology. + * .socket: tracks information on the count of cores per socket. + * .smp: keeps track of the machine topology. + * + */ +S390Topology s390_topology = { + /* will be initialized after the cpu model is realized */ + .cores_per_socket = NULL, + .smp = NULL, +}; + +/** + * s390_socket_nb: + * @cpu: s390x CPU + * + * Returns the socket number used inside the cores_per_socket array + * for a cpu. + */ +int s390_socket_nb(S390CPU *cpu) +{ + return (cpu->env.drawer_id * s390_topology.smp->books + cpu->env.book_id) * + s390_topology.smp->sockets + cpu->env.socket_id; +} + +/** + * s390_has_topology: + * + * Return value: if the topology is supported by the machine. + */ +bool s390_has_topology(void) +{ + return false; +} + +/** + * s390_topology_init: + * @ms: the machine state where the machine topology is defined + * + * Keep track of the machine topology. + * + * Allocate an array to keep the count of cores per socket. + * The index of the array starts at socket 0 from book 0 and + * drawer 0 up to the maximum allowed by the machine topology. + */ +static void s390_topology_init(MachineState *ms) +{ + CpuTopology *smp = &ms->smp; + + s390_topology.smp = smp; + s390_topology.cores_per_socket = g_new0(uint8_t, smp->sockets * + smp->books * smp->drawers); +} + +/** + * s390_topology_cpu_default: + * @cpu: pointer to a S390CPU + * @errp: Error pointer + * + * Setup the default topology for unset attributes. + * + * The function accept only all all default values or all set values + * for the geometry topology. + * + * The function calculates the (drawer_id, book_id, socket_id) + * topology by filling the cores starting from the first socket + * (0, 0, 0) up to the last (smp->drawers, smp->books, smp->sockets). + * + * CPU type, polarity and dedication have defaults values set in the + * s390x_cpu_properties. + */ +static void s390_topology_cpu_default(S390CPU *cpu, Error **errp) +{ + CpuTopology *smp = s390_topology.smp; + CPUS390XState *env = &cpu->env; + + /* All geometry topology attributes must be set or all unset */ + if ((env->socket_id < 0 || env->book_id < 0 || env->drawer_id < 0) && + (env->socket_id >= 0 || env->book_id >= 0 || env->drawer_id >= 0)) { + error_setg(errp, + "Please define all or none of the topology geometry attributes"); + return; + } + + /* Check if one of the geometry topology is unset */ + if (env->socket_id < 0) { + /* Calculate default geometry topology attributes */ + env->socket_id = (env->core_id / smp->cores) % smp->sockets; + env->book_id = (env->core_id / (smp->sockets * smp->cores)) % + smp->books; + env->drawer_id = (env->core_id / + (smp->books * smp->sockets * smp->cores)) % + smp->drawers; + } +} + +/** + * s390_topology_check: + * @cpu: s390x CPU to be verified + * @errp: Error pointer + * + * The function first setup default values and then checks if the cpu + * fits inside the system topology. + */ +static void s390_topology_check(S390CPU *cpu, Error **errp) +{ + CpuTopology *smp = s390_topology.smp; + ERRP_GUARD(); + + s390_topology_cpu_default(cpu, errp); + if (*errp) { + return; + } + + if (cpu->env.socket_id > smp->sockets) { + error_setg(errp, "Unavailable socket: %d", cpu->env.socket_id); + return; + } + if (cpu->env.book_id > smp->books) { + error_setg(errp, "Unavailable book: %d", cpu->env.book_id); + return; + } + if (cpu->env.drawer_id > smp->drawers) { + error_setg(errp, "Unavailable drawer: %d", cpu->env.drawer_id); + return; + } + if (cpu->env.entitlement >= POLARITY_MAX) { + error_setg(errp, "Unknown polarity: %d", cpu->env.entitlement); + return; + } + + /* Dedication, boolean, can not be wrong. */ +} + +/** + * s390_set_core_in_socket: + * @cpu: the new S390CPU to insert in the topology structure + * @drawer_id: new drawer_id + * @book_id: new book_id + * @socket_id: new socket_id + * @creation: if is true the CPU is a new CPU and there is no old socket + * to handle. + * if is false, this is a moving the CPU and old socket count + * must be decremented. + * @errp: the error pointer + * + */ +static void s390_set_core_in_socket(S390CPU *cpu, int drawer_id, int book_id, + int socket_id, bool creation, Error **errp) +{ + int old_socket = s390_socket_nb(cpu); + int new_socket; + + if (creation) { + new_socket = old_socket; + } else { + new_socket = drawer_id * s390_topology.smp->books + + book_id * s390_topology.smp->sockets + + socket_id; + } + + /* Check for space on new socket */ + if ((new_socket != old_socket) && + (s390_topology.cores_per_socket[new_socket] >= + s390_topology.smp->cores)) { + error_setg(errp, "No more space on this socket"); + return; + } + + /* Update the count of cores in sockets */ + s390_topology.cores_per_socket[new_socket] += 1; + if (!creation) { + s390_topology.cores_per_socket[old_socket] -= 1; + } +} + +/** + * s390_update_cpu_props: + * @ms: the machine state + * @cpu: the CPU for which to update the properties from the environment. + * + */ +static void s390_update_cpu_props(MachineState *ms, S390CPU *cpu) +{ + CpuInstanceProperties *props; + + props = &ms->possible_cpus->cpus[cpu->env.core_id].props; + + props->socket_id = cpu->env.socket_id; + props->book_id = cpu->env.book_id; + props->drawer_id = cpu->env.drawer_id; +} + +/** + * s390_topology_set_cpu: + * @ms: MachineState used to initialize the topology structure on + * first call. + * @cpu: the new S390CPU to insert in the topology structure + * @errp: the error pointer + * + * Called from CPU Hotplug to check and setup the CPU attributes + * before to insert the CPU in the topology. + */ +void s390_topology_set_cpu(MachineState *ms, S390CPU *cpu, Error **errp) +{ + ERRP_GUARD(); + + /* + * We do not want to initialize the topology if the cpu model + * does not support topology consequently, we have to wait for + * the first CPU to be realized, which realizes the CPU model + * to initialize the topology structures. + * + * s390_topology_set_cpu() is called from the cpu hotplug. + */ + if (!s390_topology.cores_per_socket) { + s390_topology_init(ms); + } + + s390_topology_check(cpu, errp); + if (*errp) { + return; + } + + /* Set the CPU inside the socket */ + s390_set_core_in_socket(cpu, 0, 0, 0, true, errp); + if (*errp) { + return; + } + + /* topology tree is reflected in props */ + s390_update_cpu_props(ms, cpu); +} diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index f3cc845d3b..9bc51a83f4 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -44,6 +44,7 @@ #include "hw/s390x/pv.h" #include "migration/blocker.h" #include "qapi/visitor.h" +#include "hw/s390x/cpu-topology.h" static Error *pv_mig_blocker; @@ -310,10 +311,18 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev, { MachineState *ms = MACHINE(hotplug_dev); S390CPU *cpu = S390_CPU(dev); + ERRP_GUARD(); g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu); ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev); + if (s390_has_topology()) { + s390_topology_set_cpu(ms, cpu, errp); + if (*errp) { + return; + } + } + if (dev->hotplugged) { raise_irq_cpu_hotplug(); } @@ -551,11 +560,21 @@ static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms) sizeof(CPUArchId) * max_cpus); ms->possible_cpus->len = max_cpus; for (i = 0; i < ms->possible_cpus->len; i++) { + CpuInstanceProperties *props = &ms->possible_cpus->cpus[i].props; + ms->possible_cpus->cpus[i].type = ms->cpu_type; ms->possible_cpus->cpus[i].vcpus_count = 1; ms->possible_cpus->cpus[i].arch_id = i; - ms->possible_cpus->cpus[i].props.has_core_id = true; - ms->possible_cpus->cpus[i].props.core_id = i; + + props->has_core_id = true; + props->core_id = i; + props->has_socket_id = true; + props->socket_id = i / ms->smp.cores; + props->has_book_id = true; + props->book_id = i / (ms->smp.cores * ms->smp.sockets); + props->has_drawer_id = true; + props->drawer_id = i / + (ms->smp.cores * ms->smp.sockets * ms->smp.books); } return ms->possible_cpus; diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build index f291016fee..58dfbdff4f 100644 --- a/hw/s390x/meson.build +++ b/hw/s390x/meson.build @@ -24,6 +24,7 @@ s390x_ss.add(when: 'CONFIG_KVM', if_true: files( 's390-stattrib-kvm.c', 'pv.c', 's390-pci-kvm.c', + 'cpu-topology.c', )) s390x_ss.add(when: 'CONFIG_TCG', if_true: files( 'tod-tcg.c',
The topology information are attributes of the CPU and are specified during the CPU device creation. On hot plug we: - calculate the default values for the topology for drawers, books and sockets in the case they are not specified. - verify the CPU attributes - check that we have still room on the desired socket The possibility to insert a CPU in a mask is dependent on the number of cores allowed in a socket, a book or a drawer, the checking is done during the hot plug of the CPU to have an immediate answer. If the complete topology is not specified, the core is added in the physical topology based on its core ID and it gets defaults values for the modifier attributes. This way, starting QEMU without specifying the topology can still get some advantage of the CPU topology. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> --- include/hw/s390x/cpu-topology.h | 24 +++ hw/s390x/cpu-topology.c | 256 ++++++++++++++++++++++++++++++++ hw/s390x/s390-virtio-ccw.c | 23 ++- hw/s390x/meson.build | 1 + 4 files changed, 302 insertions(+), 2 deletions(-) create mode 100644 hw/s390x/cpu-topology.c