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s390x cleanups and CPU hotplug via device_add

PATCH Superseded David Hildenbrand 5 participants 39 messages Sep 11, 2017 – Sep 13, 2017

v4 of 5 Superseded Latest is v5 →

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#0 lore raw

v4 cover s390x cleanups and CPU hotplug via device_add

The first patches are a bunch of cleanups. I decided to go the extra mile and implement CPU hotplug via "device_add", as well as "query-hotpluggable-cpus".

On s390x, only complete cores can be plugged. CPU hot unplug is currently not supported by the architecture.

Support for hotplugging CPUs in random core-id order (last two patches) is added. We once hat a KVM bug preventing this, but the stable patch should now be included in relevant places - 152e9f65d66f ("KVM: s390: fix wrong lookup of VCPUs by array index"). Current tooling will plug them in sequential order anyway, so it should not hurt.

v3 -> v4:
* Dropped "target/s390x: move typedef of S390CPU to its definition"
* Added "target/s390x: move some s390x typedefs to cpu-qom.h"
- this moves some typedefs and makes cpu-qom.h independent from cpu_models.h. This is necessary to cleanly use cpu-qom.h in sclp.c later.
* "s390x: move sclp_service_call() to sclp.h"
- Use cpu-qom.h now as a s390x replacement for typedefs.h
* "target/s390x: use "core-id" for cpu number/address/id handling"
- Indicate also in error messages the property name "core-id". So just the error messages were touched.

David Hildenbrand (21):
exec,dump,i386,ppc,s390x: don't include exec/cpu-all.h explicitly
cpu: drop old comments describing members
s390x: get rid of s390-virtio.c
s390x: rename s390-virtio.h to s390-virtio-hcall.h
s390x: move s390_virtio_hypercall() to s390-virtio-hcall.h
s390x: move subsystem_reset() to s390-virtio-ccw.h target/s390x: move some s390x typedefs to cpu-qom.h
s390x: move sclp_service_call() to sclp.h target/s390x: use trigger_pgm_exception() in

    s390_cpu_handle_mmu_fault()

target/s390x: use program_interrupt() in per_check_exception()
s390x: allow only 1 CPU with TCG
target/s390x: set cpu->id for linux user when realizing target/s390x: use "core-id" for cpu number/address/id handling target/s390x: rename next_cpu_id to next_core_id
s390x: print CPU definitions in sorted order
s390x: allow cpu hotplug via device_add
s390x: CPU hot unplug via device_del cannot work for now
s390x: implement query-hotpluggable-cpus
s390x: get rid of cpu_s390x_create()
s390x: generate sclp cpu information from possible_cpus
s390x: allow CPU hotplug in random core-id order

 dump.c                             |   1 -
 exec.c                             |   1 -
 hw/s390x/Makefile.objs             |   1 -
 hw/s390x/s390-virtio-ccw.c         | 245 +++++++++++++++++++++++++++++++++++--
 hw/s390x/s390-virtio-hcall.c       |   2 +-
 hw/s390x/s390-virtio-hcall.h       |  21 ++++
 hw/s390x/s390-virtio.c             |  37 ------
 hw/s390x/s390-virtio.h             |  35 ------
 hw/s390x/sclp.c                    |  34 +++--
 include/hw/s390x/s390-virtio-ccw.h |   2 +
 include/hw/s390x/sclp.h            |   2 +
 include/qom/cpu.h                  |   6 +-
 qapi-schema.json                   |  16 +++
 target/i386/arch_dump.c            |   1 -
 target/i386/arch_memory_mapping.c  |   1 -
 target/i386/svm_helper.c           |   1 -
 target/ppc/arch_dump.c             |   1 -
 target/s390x/arch_dump.c           |   1 -
 target/s390x/cpu-qom.h             |   7 +-
 target/s390x/cpu.c                 | 102 ++++++---------
 target/s390x/cpu.h                 |  18 +--
 target/s390x/cpu_models.c          |  58 ++++++---
 target/s390x/cpu_models.h          |   8 +-
 target/s390x/diag.c                |   1 +
 target/s390x/excp_helper.c         |   5 +-
 target/s390x/helper.c              |  47 +------
 target/s390x/internal.h            |   1 -
 target/s390x/kvm.c                 |   1 +
 target/s390x/misc_helper.c         |  21 ++--
 target/s390x/translate.c           |   5 +-
 30 files changed, 410 insertions(+), 272 deletions(-)
 create mode 100644 hw/s390x/s390-virtio-hcall.h
 delete mode 100644 hw/s390x/s390-virtio.h
Signature · 1 line
2.13.5
#1 lore raw

PATCH v4 1/21 exec, dump, i386, ppc, s390x: don't include exec/cpu-all.h explicitly

All but a handful of files include exec/cpu-all.h via cpu.h only. As these files already include cpu.h, let's just drop the additional include.

---
 dump.c                            | 1 -
 exec.c                            | 1 -
 target/i386/arch_dump.c           | 1 -
 target/i386/arch_memory_mapping.c | 1 -
 target/i386/svm_helper.c          | 1 -
 target/ppc/arch_dump.c            | 1 -
 target/s390x/arch_dump.c          | 1 -
 7 files changed, 7 deletions(-)
dump.c +0 -1
index a79773d0f7..2ef6a678e8 100644
@@ -15,7 +15,6 @@
 #include "qemu/cutils.h"
 #include "elf.h"
 #include "cpu.h"
-#include "exec/cpu-all.h"
 #include "exec/hwaddr.h"
 #include "monitor/monitor.h"
 #include "sysemu/kvm.h"
exec.c +0 -1
index d20c34ca83..a25a4c6018 100644
@@ -56,7 +56,6 @@
 #endif
 
 #endif
-#include "exec/cpu-all.h"
 #include "qemu/rcu_queue.h"
 #include "qemu/main-loop.h"
 #include "translate-all.h"
target/i386/arch_dump.c +0 -1
index e682904052..35b55fc200 100644
@@ -13,7 +13,6 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
-#include "exec/cpu-all.h"
 #include "sysemu/dump.h"
 #include "elf.h"
 #include "sysemu/memory_mapping.h"
target/i386/arch_memory_mapping.c +0 -1
index 647cff2829..271cb5e41b 100644
@@ -13,7 +13,6 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
-#include "exec/cpu-all.h"
 #include "sysemu/memory_mapping.h"
 
 /* PAE Paging or IA-32e Paging */
target/i386/svm_helper.c +0 -1
index 59e8b5091c..f479239875 100644
@@ -19,7 +19,6 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
-#include "exec/cpu-all.h"
 #include "exec/helper-proto.h"
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
target/ppc/arch_dump.c +0 -1
index 8e9397aa58..beb7268e57 100644
@@ -15,7 +15,6 @@
 #include "qemu/osdep.h"
 #include "cpu.h"
 #include "elf.h"
-#include "exec/cpu-all.h"
 #include "sysemu/dump.h"
 #include "sysemu/kvm.h"
 
target/s390x/arch_dump.c +0 -1
index 9b0bf92698..6f61ff95af 100644
@@ -15,7 +15,6 @@
 #include "cpu.h"
 #include "internal.h"
 #include "elf.h"
-#include "exec/cpu-all.h"
 #include "sysemu/dump.h"
 
 
Signature · 1 line
2.13.5
#2 lore raw

PATCH v4 2/21 cpu: drop old comments describing members

In reply to David Hildenbrand

These comments are obviously stale.

---
 include/qom/cpu.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
include/qom/cpu.h +3 -3
index 995a7beeb5..0dc767a753 100644
@@ -388,10 +388,10 @@ struct CPUState {
     DECLARE_BITMAP(trace_dstate, CPU_TRACE_DSTATE_MAX_EVENTS);
 
     /* TODO Move common fields from CPUArchState here. */
-    int cpu_index; /* used by alpha TCG */
-    uint32_t halted; /* used by alpha, cris, ppc TCG */
+    int cpu_index;
+    uint32_t halted;
     uint32_t can_do_io;
-    int32_t exception_index; /* used by m68k TCG */
+    int32_t exception_index;
 
     /* shared by kvm, hax and hvf */
     bool vcpu_dirty;
Signature · 1 line
2.13.5
#3 lore raw

PATCH v4 3/21 s390x: get rid of s390-virtio.c

In reply to David Hildenbrand

It is a leftover from the days where we had still the !ccw virtio machine. As this one is long gone, let's move everything to s390-virtio-ccw.c.

---
 hw/s390x/Makefile.objs     |   1 -
 hw/s390x/s390-virtio-ccw.c | 157 ++++++++++++++++++++++++++++++++++++++++++++-
 hw/s390x/s390-virtio.c     |  37 -----------
 hw/s390x/s390-virtio.h     |  15 -----
 4 files changed, 156 insertions(+), 54 deletions(-)
hw/s390x/Makefile.objs +0 -1
index 7ee19d3abc..dc704b57d6 100644
@@ -1,4 +1,3 @@
-obj-y += s390-virtio.o
 obj-y += s390-virtio-hcall.o
 obj-y += sclp.o
 obj-y += event-facility.o
hw/s390x/s390-virtio-ccw.c +156 -1

198 lines not on this page · raw message

hw/s390x/s390-virtio.c +0 -37
index da3f49e80e..9316be1cfc 100644
@@ -48,17 +48,6 @@
 #define S390_TOD_CLOCK_VALUE_MISSING    0x00
 #define S390_TOD_CLOCK_VALUE_PRESENT    0x01
 
-static S390CPU **cpu_states;
-
-S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
-{
-    if (cpu_addr >= max_cpus) {
-        return NULL;
-    }
-
-    /* Fast lookup via CPU ID */
-    return cpu_states[cpu_addr];
-}
 
 void s390_init_ipl_dev(const char *kernel_filename,
                        const char *kernel_cmdline,
@@ -86,32 +75,6 @@ void s390_init_ipl_dev(const char *kernel_filename,
     qdev_init_nofail(dev);
 }
 
-void s390_init_cpus(MachineState *machine)
-{
-    int i;
-    gchar *name;
-
-    if (machine->cpu_model == NULL) {
-        machine->cpu_model = s390_default_cpu_model_name();
-    }
-
-    cpu_states = g_new0(S390CPU *, max_cpus);
-
-    for (i = 0; i < max_cpus; i++) {
-        name = g_strdup_printf("cpu[%i]", i);
-        object_property_add_link(OBJECT(machine), name, TYPE_S390_CPU,
-                                 (Object **) &cpu_states[i],
-                                 object_property_allow_set_link,
-                                 OBJ_PROP_LINK_UNREF_ON_RELEASE,
-                                 &error_abort);
-        g_free(name);
-    }
-
-    for (i = 0; i < smp_cpus; i++) {
-        s390x_new_cpu(machine->cpu_model, i, &error_fatal);
-    }
-}
-
 
 void s390_create_virtio_net(BusState *bus, const char *name)
 {
hw/s390x/s390-virtio.h +0 -15
index ca97fd6814..d984cd4115 100644
@@ -12,24 +12,9 @@
 #ifndef HW_S390_VIRTIO_H
 #define HW_S390_VIRTIO_H
 
-#include "hw/nmi.h"
 #include "standard-headers/asm-s390/kvm_virtio.h"
 #include "standard-headers/asm-s390/virtio-ccw.h"
 
 typedef int (*s390_virtio_fn)(const uint64_t *args);
 void s390_register_virtio_hypercall(uint64_t code, s390_virtio_fn fn);
-
-void s390_init_cpus(MachineState *machine);
-void s390_init_ipl_dev(const char *kernel_filename,
-                       const char *kernel_cmdline,
-                       const char *initrd_filename,
-                       const char *firmware,
-                       const char *netboot_fw,
-                       bool enforce_bios);
-void s390_create_virtio_net(BusState *bus, const char *name);
-void s390_nmi(NMIState *n, int cpu_index, Error **errp);
-void s390_machine_reset(void);
-void s390_memory_init(ram_addr_t mem_size);
-void gtod_save(QEMUFile *f, void *opaque);
-int gtod_load(QEMUFile *f, void *opaque, int version_id);
 #endif
Signature · 1 line
2.13.5
#4 lore raw

PATCH v4 4/21 s390x: rename s390-virtio.h to s390-virtio-hcall.h

In reply to David Hildenbrand

The only interface left, so let's properly rename it.

---
 hw/s390x/s390-virtio-ccw.c                      | 2 +-
 hw/s390x/s390-virtio-hcall.c                    | 2 +-
 hw/s390x/{s390-virtio.h => s390-virtio-hcall.h} | 8 ++++----
 3 files changed, 6 insertions(+), 6 deletions(-)
 rename hw/s390x/{s390-virtio.h => s390-virtio-hcall.h} (77%)
hw/s390x/s390-virtio-ccw.c +1 -1
index 4c3a3e177b..f67b4b5d58 100644
@@ -16,7 +16,7 @@
 #include "cpu.h"
 #include "hw/boards.h"
 #include "exec/address-spaces.h"
-#include "s390-virtio.h"
+#include "hw/s390x/s390-virtio-hcall.h"
 #include "hw/s390x/sclp.h"
 #include "hw/s390x/s390_flic.h"
 #include "hw/s390x/ioinst.h"
hw/s390x/s390-virtio-hcall.c +1 -1
index 23d67d6170..ec7cf8beb3 100644
@@ -11,7 +11,7 @@
 
 #include "qemu/osdep.h"
 #include "cpu.h"
-#include "hw/s390x/s390-virtio.h"
+#include "hw/s390x/s390-virtio-hcall.h"
 
 #define MAX_DIAG_SUBCODES 255
 
hw/s390x/s390-virtio-hcall.h renamed from hw/s390x/s390-virtio.h +4 -4
similarity index 77%
rename from hw/s390x/s390-virtio.h
rename to hw/s390x/s390-virtio-hcall.h
index d984cd4115..59fcba3a06 100644
@@ -1,5 +1,5 @@
 /*
- * Virtio interfaces for s390
+ * Support for virtio hypercalls on s390x
  *
  * Copyright 2012 IBM Corp.
  * Author(s): Cornelia Huck <[email protected]>
@@ -9,12 +9,12 @@
  * directory.
  */
 
-#ifndef HW_S390_VIRTIO_H
-#define HW_S390_VIRTIO_H
+#ifndef HW_S390_VIRTIO_HCALL_H
+#define HW_S390_VIRTIO_HCALL_H
 
 #include "standard-headers/asm-s390/kvm_virtio.h"
 #include "standard-headers/asm-s390/virtio-ccw.h"
 
 typedef int (*s390_virtio_fn)(const uint64_t *args);
 void s390_register_virtio_hypercall(uint64_t code, s390_virtio_fn fn);
-#endif
+#endif /* HW_S390_VIRTIO_HCALL_H */
Signature · 1 line
2.13.5
#5 lore raw

PATCH v4 5/21 s390x: move s390_virtio_hypercall() to s390-virtio-hcall.h

In reply to David Hildenbrand

Implemented in hw/s390x/s390-virtio-hcall.c, so let's move it to the right header file.

---
 hw/s390x/s390-virtio-hcall.h | 1 +
 target/s390x/cpu.h           | 1 -
 target/s390x/kvm.c           | 1 +
 target/s390x/misc_helper.c   | 1 +
 4 files changed, 3 insertions(+), 1 deletion(-)
hw/s390x/s390-virtio-hcall.h +1 -0
index 59fcba3a06..cbc270eef3 100644
@@ -17,4 +17,5 @@
 
 typedef int (*s390_virtio_fn)(const uint64_t *args);
 void s390_register_virtio_hypercall(uint64_t code, s390_virtio_fn fn);
+int s390_virtio_hypercall(CPUS390XState *env);
 #endif /* HW_S390_VIRTIO_HCALL_H */
target/s390x/cpu.h +0 -1
index 0bd97a5670..7073fa59e9 100644
@@ -723,6 +723,5 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
 extern void subsystem_reset(void);
 int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
-int s390_virtio_hypercall(CPUS390XState *env);
 
 #endif
target/s390x/kvm.c +1 -0
index d07763ff2c..ed59896423 100644
@@ -48,6 +48,7 @@
 #include "hw/s390x/ebcdic.h"
 #include "exec/memattrs.h"
 #include "hw/s390x/s390-virtio-ccw.h"
+#include "hw/s390x/s390-virtio-hcall.h"
 
 #ifndef DEBUG_KVM
 #define DEBUG_KVM  0
target/s390x/misc_helper.c +1 -0
index 50cc046ca2..b142db71c6 100644
@@ -34,6 +34,7 @@
 #include "sysemu/cpus.h"
 #include "sysemu/sysemu.h"
 #include "hw/s390x/ebcdic.h"
+#include "hw/s390x/s390-virtio-hcall.h"
 #endif
 
 /* #define DEBUG_HELPER */
Signature · 1 line
2.13.5
#6 lore raw

PATCH v4 6/21 s390x: move subsystem_reset() to s390-virtio-ccw.h

In reply to David Hildenbrand

Implemented in s390-virtio-ccw.c, so move it to the right header. We can also drop the extern. Fix up one include.

---
 include/hw/s390x/s390-virtio-ccw.h | 2 ++
 target/s390x/cpu.h                 | 1 -
 target/s390x/diag.c                | 1 +
 3 files changed, 3 insertions(+), 1 deletion(-)
include/hw/s390x/s390-virtio-ccw.h +2 -0
index 41a9d2862b..a9a90c2022 100644
@@ -56,4 +56,6 @@ bool gs_allowed(void);
  */
 bool css_migration_enabled(void);
 
+void subsystem_reset(void);
+
 #endif
target/s390x/cpu.h +0 -1
index 7073fa59e9..372f7d8885 100644
@@ -721,7 +721,6 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 
 /* outside of target/s390x/ */
 S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
-extern void subsystem_reset(void);
 int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
 
 #endif
target/s390x/diag.c +1 -0
index e6b5e6de37..82a623948d 100644
@@ -20,6 +20,7 @@
 #include "hw/watchdog/wdt_diag288.h"
 #include "sysemu/cpus.h"
 #include "hw/s390x/ipl.h"
+#include "hw/s390x/s390-virtio-ccw.h"
 
 static int modified_clear_reset(S390CPU *cpu)
 {
Signature · 1 line
2.13.5
#7 lore raw

PATCH v4 7/21 target/s390x: move some s390x typedefs to cpu-qom.h

In reply to David Hildenbrand

This allows us to drop inclusion of cpu_models.h in cpu-qom.h, and prepares for using cpu-qom.h as a s390 specific version of typedefs.h

---
 target/s390x/cpu-qom.h    | 5 ++++-
 target/s390x/cpu.h        | 5 +++--
 target/s390x/cpu_models.h | 8 ++++----
 3 files changed, 11 insertions(+), 7 deletions(-)
target/s390x/cpu-qom.h +4 -1
index 4e936e7788..2435cd8390 100644
@@ -21,7 +21,6 @@
 #define QEMU_S390_CPU_QOM_H
 
 #include "qom/cpu.h"
-#include "cpu_models.h"
 
 #define TYPE_S390_CPU "s390-cpu"
 
@@ -32,6 +31,9 @@
 #define S390_CPU_GET_CLASS(obj) \
     OBJECT_GET_CLASS(S390CPUClass, (obj), TYPE_S390_CPU)
 
+typedef struct S390CPUModel S390CPUModel;
+typedef struct S390CPUDef S390CPUDef;
+
 /**
  * S390CPUClass:
  * @parent_realize: The parent class' realize handler.
@@ -62,5 +64,6 @@ typedef struct S390CPUClass {
 } S390CPUClass;
 
 typedef struct S390CPU S390CPU;
+typedef struct CPUS390XState CPUS390XState;
 
 #endif
target/s390x/cpu.h +3 -2
index 372f7d8885..4a0a59dfbc 100644
@@ -25,6 +25,7 @@
 
 #include "qemu-common.h"
 #include "cpu-qom.h"
+#include "cpu_models.h"
 
 #define TARGET_LONG_BITS 64
 
@@ -80,7 +81,7 @@ typedef struct MchkQueue {
     uint16_t type;
 } MchkQueue;
 
-typedef struct CPUS390XState {
+struct CPUS390XState {
     uint64_t regs[16];     /* GP registers */
     /*
      * The floating point registers are part of the vector registers.
@@ -174,7 +175,7 @@ typedef struct CPUS390XState {
     /* currently processed sigp order */
     uint8_t sigp_order;
 
-} CPUS390XState;
+};
 
 static inline CPU_DoubleU *get_freg(CPUS390XState *cs, int nr)
 {
target/s390x/cpu_models.h +4 -4
index c0bee15d7a..4c6dee1871 100644
@@ -17,7 +17,7 @@
 #include "qom/cpu.h"
 
 /* static CPU definition */
-typedef struct S390CPUDef {
+struct S390CPUDef {
     const char *name;       /* name exposed to the user */
     const char *desc;       /* description exposed to the user */
     uint8_t gen;            /* hw generation identification */
@@ -37,10 +37,10 @@ typedef struct S390CPUDef {
     S390FeatBitmap full_feat;
     /* used to init full_feat from generated data */
     S390FeatInit full_init;
-} S390CPUDef;
+};
 
 /* CPU model based on a CPU definition */
-typedef struct S390CPUModel {
+struct S390CPUModel {
     const S390CPUDef *def;
     S390FeatBitmap features;
     /* values copied from the "host" model, can change during migration */
@@ -48,7 +48,7 @@ typedef struct S390CPUModel {
     uint32_t cpu_id;        /* CPU id */
     uint8_t cpu_id_format;  /* CPU id format bit */
     uint8_t cpu_ver;        /* CPU version, usually "ff" for kvm */
-} S390CPUModel;
+};
 
 /*
  * CPU ID
Signature · 1 line
2.13.5
#8 lore raw

PATCH v4 8/21 s390x: move sclp_service_call() to sclp.h

In reply to David Hildenbrand

Implemented in sclp.c, so let's move it to the right include file. Fix up one include. Do a forward declaration of struct CPUS390XState to fix the two sclp consoles complaining.

---
 include/hw/s390x/sclp.h    | 2 ++
 target/s390x/cpu.h         | 1 -
 target/s390x/misc_helper.c | 1 +
 3 files changed, 3 insertions(+), 1 deletion(-)
include/hw/s390x/sclp.h +2 -0
index a72d096081..847ff32f85 100644
@@ -16,6 +16,7 @@
 
 #include "hw/sysbus.h"
 #include "hw/qdev.h"
+#include "target/s390x/cpu-qom.h"
 
 #define SCLP_CMD_CODE_MASK                      0xffff00ff
 
@@ -242,5 +243,6 @@ sclpMemoryHotplugDev *init_sclp_memory_hotplug_dev(void);
 sclpMemoryHotplugDev *get_sclp_memory_hotplug_dev(void);
 void sclp_service_interrupt(uint32_t sccb);
 void raise_irq_cpu_hotplug(void);
+int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
 
 #endif
target/s390x/cpu.h +0 -1
index 4a0a59dfbc..5295bd3c66 100644
@@ -722,6 +722,5 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 
 /* outside of target/s390x/ */
 S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
-int sclp_service_call(CPUS390XState *env, uint64_t sccb, uint32_t code);
 
 #endif
target/s390x/misc_helper.c +1 -0
index b142db71c6..8b07535b02 100644
@@ -35,6 +35,7 @@
 #include "sysemu/sysemu.h"
 #include "hw/s390x/ebcdic.h"
 #include "hw/s390x/s390-virtio-hcall.h"
+#include "hw/s390x/sclp.h"
 #endif
 
 /* #define DEBUG_HELPER */
Signature · 1 line
2.13.5
#9 lore raw

PATCH v4 9/21 target/s390x: use trigger_pgm_exception() in s390_cpu_handle_mmu_fault()

In reply to David Hildenbrand

This looks cleaner. linux-user will not use the ilen field, so setting it doesn't do any harm.

---
 target/s390x/excp_helper.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
target/s390x/excp_helper.c +1 -2
index 361f970db3..14d3160e92 100644
@@ -59,8 +59,7 @@ int s390_cpu_handle_mmu_fault(CPUState *cs, vaddr address,
 {
     S390CPU *cpu = S390_CPU(cs);
 
-    cs->exception_index = EXCP_PGM;
-    cpu->env.int_pgm_code = PGM_ADDRESSING;
+    trigger_pgm_exception(&cpu->env, PGM_ADDRESSING, ILEN_AUTO);
     /* On real machines this value is dropped into LowMem.  Since this
        is userland, simply put this someplace that cpu_loop can find it.  */
     cpu->env.__excp_addr = address;
Signature · 1 line
2.13.5
#10 lore raw

PATCH v4 10/21 target/s390x: use program_interrupt() in per_check_exception()

In reply to David Hildenbrand

Clean it up by reusing program_interrupt(). Add a concern regarding ilen.

---
 target/s390x/misc_helper.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)
target/s390x/misc_helper.c +9 -6
index 8b07535b02..f3624d75eb 100644
@@ -447,14 +447,17 @@ void HELPER(chsc)(CPUS390XState *env, uint64_t inst)
 #ifndef CONFIG_USER_ONLY
 void HELPER(per_check_exception)(CPUS390XState *env)
 {
-    CPUState *cs = CPU(s390_env_get_cpu(env));
+    uint32_t ilen;
 
     if (env->per_perc_atmid) {
-        env->int_pgm_code = PGM_PER;
-        env->int_pgm_ilen = get_ilen(cpu_ldub_code(env, env->per_address));
-
-        cs->exception_index = EXCP_PGM;
-        cpu_loop_exit(cs);
+        /*
+         * FIXME: ILEN_AUTO is most probably the right thing to use. ilen
+         * always has to match the instruction referenced in the PSW. E.g.
+         * if a PER interrupt is triggered via EXECUTE, we have to use ilen
+         * of EXECUTE, while per_address contains the target of EXECUTE.
+         */
+        ilen = get_ilen(cpu_ldub_code(env, env->per_address));
+        program_interrupt(env, PGM_PER, ilen);
     }
 }
 
Signature · 1 line
2.13.5
#11 lore raw

PATCH v4 11/21 s390x: allow only 1 CPU with TCG

In reply to David Hildenbrand

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +10 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
+/* #define S390_TCG_SMP_SUPPORT */
+
 static void s390_init_cpus(MachineState *machine)
 {
     int i;
@@ -55,6 +58,13 @@ static void s390_init_cpus(MachineState *machine)
     if (machine->cpu_model == NULL) {
         machine->cpu_model = s390_default_cpu_model_name();
     }
+#ifndef S390_TCG_SMP_SUPPORT
+    if (tcg_enabled() && max_cpus > 1) {
+        error_report("Number of SMP CPUs requested (%d) exceeds max CPUs "
+                     "supported by TCG (1) on s390x", max_cpus);
+        exit(1);
+    }
+#endif
 
     cpu_states = g_new0(S390CPU *, max_cpus);
 
Signature · 1 line
2.13.5
#12 lore raw

Re: [Qemu-devel] [PATCH v4 11/21] s390x: allow only 1 CPU with TCG

Quoted 26 lines · On Mon, 11 Sep 2017 17:21:40 +0200 David Hildenbrand <[email protected]> wrote:

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +1 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"

hw/s390x/s390-virtio-ccw.c S390CPU *s390_cpu_addr2state(uint16_t cpu_addr) · line 51

Quoted 4 lines
hw/s390x/s390-virtio-ccw.c +1 -0
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
+/* #define S390_TCG_SMP_SUPPORT */

I'd drop define and ifdef for something that doesn't exists

Quoted 17 lines
hw/s390x/s390-virtio-ccw.c +7 -0
 static void s390_init_cpus(MachineState *machine)
 {
     int i;
@@ -55,6 +58,13 @@ static void s390_init_cpus(MachineState *machine)
     if (machine->cpu_model == NULL) {
         machine->cpu_model = s390_default_cpu_model_name();
     }
+#ifndef S390_TCG_SMP_SUPPORT
+    if (tcg_enabled() && max_cpus > 1) {
+        error_report("Number of SMP CPUs requested (%d) exceeds max CPUs "
+                     "supported by TCG (1) on s390x", max_cpus);
+        exit(1);
+    }
+#endif
 
     cpu_states = g_new0(S390CPU *, max_cpus);
 
#13 lore raw

Re: [Qemu-devel] [PATCH v4 11/21] s390x: allow only 1 CPU with TCG

Quoted 32 lines · Igor Mammedov
Quoted 29 lines · On Mon, 11 Sep 2017 17:21:40 +0200 David Hildenbrand <[email protected]> wrote:

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +1 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
Quoted 2 lines

hw/s390x/s390-virtio-ccw.c S390CPU *s390_cpu_addr2state(uint16_t cpu_addr) · line 51

Quoted 1 line
hw/s390x/s390-virtio-ccw.c +1 -0
+/* #define S390_TCG_SMP_SUPPORT */

I'd drop define and ifdef for something that doesn't exists

Conny requested it as we might see some work on that area (supporting smp) soon. So as long as there are no other opinions, I'll stick to the current version.

Thanks!

Signature · 3 lines
Thanks,

David
#14 lore raw

Re: [Qemu-devel] [PATCH v4 11/21] s390x: allow only 1 CPU with TCG

Quoted 33 lines · On Tue, 12 Sep 2017 17:42:35 +0200 David Hildenbrand <[email protected]> wrote:
Quoted 32 lines · Igor Mammedov
Quoted 29 lines · On Mon, 11 Sep 2017 17:21:40 +0200 David Hildenbrand <[email protected]> wrote:

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +1 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
Quoted 9 lines
Quoted 2 lines

hw/s390x/s390-virtio-ccw.c S390CPU *s390_cpu_addr2state(uint16_t cpu_addr) · line 51

Quoted 1 line
hw/s390x/s390-virtio-ccw.c +1 -0
+/* #define S390_TCG_SMP_SUPPORT */  

I'd drop define and ifdef for something that doesn't exists

Conny requested it as we might see some work on that area (supporting smp) soon. So as long as there are no other opinions, I'll stick to the current version.

Thanks!

I've just removed a bunch of TODO cpu models in PPC with corresponding macro, my guess they were also introduced with similar intent but ended up as dead code.

So it's better to add new code when it actually is needed, instead of just in case.

#15 lore raw

Re: [Qemu-devel] [PATCH v4 11/21] s390x: allow only 1 CPU with TCG

Quoted 43 lines · Igor Mammedov
Quoted 40 lines · On Tue, 12 Sep 2017 17:42:35 +0200 David Hildenbrand <[email protected]> wrote:
Quoted 32 lines · Igor Mammedov
Quoted 29 lines · On Mon, 11 Sep 2017 17:21:40 +0200 David Hildenbrand <[email protected]> wrote:

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +1 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
Quoted 2 lines

hw/s390x/s390-virtio-ccw.c S390CPU *s390_cpu_addr2state(uint16_t cpu_addr) · line 51

Quoted 1 line
hw/s390x/s390-virtio-ccw.c +1 -0
+/* #define S390_TCG_SMP_SUPPORT */  

I'd drop define and ifdef for something that doesn't exists

Conny requested it as we might see some work on that area (supporting smp) soon. So as long as there are no other opinions, I'll stick to the current version.

Quoted 9 lines
Quoted 2 lines

Thanks!

I've just removed a bunch of TODO cpu models in PPC with corresponding macro, my guess they were also introduced with similar intent but ended up as dead code.

So it's better to add new code when it actually is needed, instead of just in case.

v1 of this patch had no ifdef at all. So I'll let Conny decide whether to keep it like this or whether to drop the ifdef again.

Signature · 3 lines
Thanks,

David
#16 lore raw

Re: [Qemu-devel] [PATCH v4 11/21] s390x: allow only 1 CPU with TCG

Quoted 50 lines · On Wed, 13 Sep 2017 14:10:53 +0200 David Hildenbrand <[email protected]> wrote:
Quoted 49 lines · Igor Mammedov
Quoted 33 lines · On Tue, 12 Sep 2017 17:42:35 +0200 David Hildenbrand <[email protected]> wrote:
Quoted 32 lines · Igor Mammedov
Quoted 29 lines · On Mon, 11 Sep 2017 17:21:40 +0200 David Hildenbrand <[email protected]> wrote:

Specifying more than 1 CPU (e.g. -smp 5) leads to SIGP errors (the guest tries to bring these CPUs up but fails), because we don't support multiple CPUs on s390x under TCG.

Let's bail out if more than 1 is specified, so we don't raise people's hope. Make it a define, so we can easily bump it up later.

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +1 -0
index f67b4b5d58..f1198b2745 100644
@@ -23,6 +23,7 @@
 #include "hw/s390x/css.h"
 #include "virtio-ccw.h"
 #include "qemu/config-file.h"
+#include "qemu/error-report.h"
 #include "s390-pci-bus.h"
 #include "hw/s390x/storage-keys.h"
 #include "hw/s390x/storage-attributes.h"
@@ -47,6 +48,8 @@ S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
     return cpu_states[cpu_addr];
 }
 
Quoted 9 lines
Quoted 2 lines

hw/s390x/s390-virtio-ccw.c S390CPU *s390_cpu_addr2state(uint16_t cpu_addr) · line 51

Quoted 1 line
hw/s390x/s390-virtio-ccw.c +1 -0
+/* #define S390_TCG_SMP_SUPPORT */    

I'd drop define and ifdef for something that doesn't exists

Conny requested it as we might see some work on that area (supporting smp) soon. So as long as there are no other opinions, I'll stick to the current version.

Thanks!

I've just removed a bunch of TODO cpu models in PPC with corresponding macro, my guess they were also introduced with similar intent but ended up as dead code.

Quoted 5 lines
Quoted 3 lines

So it's better to add new code when it actually is needed, instead of just in case.

v1 of this patch had no ifdef at all. So I'll let Conny decide whether to keep it like this or whether to drop the ifdef again.

You could add a comment? OTOH, this one hits immediately, so whoever implements smp for tcg will remember to change this :)

So no real objection to leaving out the ifdef.

#17 lore raw

PATCH v4 12/21 target/s390x: set cpu->id for linux user when realizing

In reply to David Hildenbrand

scc->next_cpu_id is updated when realizing. Setting it just before that point looks cleaner.

---
 target/s390x/cpu.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)
target/s390x/cpu.c +4 -7
index 74b3e4fd0d..5f9315fb16 100644
@@ -194,7 +194,11 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
                    ", max allowed: %d", cpu->id, max_cpus - 1);
         goto out;
     }
+#else
+    /* implicitly set for linux-user only */
+    cpu->id = scc->next_cpu_id;
 #endif
+
     if (cpu_exists(cpu->id)) {
         error_setg(&err, "Unable to add CPU: %" PRIi64
                    ", it already exists", cpu->id);
@@ -306,13 +310,6 @@ static void s390_cpu_initfn(Object *obj)
         inited = true;
         s390x_translate_init();
     }
-
-#if defined(CONFIG_USER_ONLY)
-    {
-        S390CPUClass *scc = S390_CPU_GET_CLASS(obj);
-        cpu->id = scc->next_cpu_id;
-    }
-#endif
 }
 
 static void s390_cpu_finalize(Object *obj)
Signature · 1 line
2.13.5
Reviewed-by on v4 12/21
#18 lore raw

Re: [Qemu-devel] [PATCH v4 12/21] target/s390x: set cpu->id for linux user when realizing

Quoted 5 lines · On Mon, 11 Sep 2017 17:21:41 +0200 David Hildenbrand <[email protected]> wrote:

scc->next_cpu_id is updated when realizing. Setting it just before that point looks cleaner.

Quoted 34 lines
---
 target/s390x/cpu.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)
target/s390x/cpu.c +4 -7
index 74b3e4fd0d..5f9315fb16 100644
@@ -194,7 +194,11 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
                    ", max allowed: %d", cpu->id, max_cpus - 1);
         goto out;
     }
+#else
+    /* implicitly set for linux-user only */
+    cpu->id = scc->next_cpu_id;
 #endif
+
     if (cpu_exists(cpu->id)) {
         error_setg(&err, "Unable to add CPU: %" PRIi64
                    ", it already exists", cpu->id);
@@ -306,13 +310,6 @@ static void s390_cpu_initfn(Object *obj)
         inited = true;
         s390x_translate_init();
     }
-
-#if defined(CONFIG_USER_ONLY)
-    {
-        S390CPUClass *scc = S390_CPU_GET_CLASS(obj);
-        cpu->id = scc->next_cpu_id;
-    }
-#endif
 }
 
 static void s390_cpu_finalize(Object *obj)
#19 lore raw

PATCH v4 13/21 target/s390x: use "core-id" for cpu number/address/id handling

In reply to David Hildenbrand

Some time ago we discussed that using "id" as property name is not the right thing to do, as it is a reserved property for other devices and will not work with device_add.

Switch to the term "core-id" instead, and use it as an equivalent to "CPU address" mentioned in the PoP. There is no such thing as cpu number, so rename env.cpu_num to env.core_id. We use "core-id" as this is the common term to use for device_add later on (x86 and ppc).

We can get rid of cpu->id now. Keep cpu_index and env->core_id in sync. cpu_index was already implicitly used by e.g. cpu_exists(), so keeping both in sync seems to be the right thing to do.

cpu_index will now no longer automatically get set via cpu_exec_realizefn(). For now, we were lucky that both implicitly stayed in sync.

Our new cpu property "core-id" can be a static property. Range checks can be avoided by using the correct type and the "setting after realized" check is done implicitly.

device_add will later need the reserved "id" property. Hotplugging a CPU on s390x will then be: "device_add host-s390-cpu,id=cpu2,core-id=2".

---
 hw/s390x/s390-virtio-ccw.c |  2 +-
 target/s390x/cpu.c         | 72 +++++++++++++---------------------------------
 target/s390x/cpu.h         |  5 ++--
 target/s390x/cpu_models.c  |  2 +-
 target/s390x/excp_helper.c |  2 +-
 target/s390x/helper.c      |  4 +--
 target/s390x/misc_helper.c |  4 +--
 target/s390x/translate.c   |  5 +---
 8 files changed, 30 insertions(+), 66 deletions(-)
hw/s390x/s390-virtio-ccw.c +1 -1
index f1198b2745..2086eb6ca6 100644
@@ -314,7 +314,7 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev,
     S390CPU *cpu = S390_CPU(dev);
     CPUState *cs = CPU(dev);
 
-    name = g_strdup_printf("cpu[%i]", cpu->env.cpu_num);
+    name = g_strdup_printf("cpu[%i]", cpu->env.core_id);
     object_property_set_link(OBJECT(hotplug_dev), OBJECT(cs), name,
                              errp);
     g_free(name);
target/s390x/cpu.c +20 -52

126 lines not on this page · raw message

target/s390x/cpu.h +2 -3
index 5295bd3c66..1c8456fa57 100644
@@ -150,7 +150,7 @@ struct CPUS390XState {
 
     CPU_COMMON
 
-    uint32_t cpu_num;
+    uint32_t core_id; /* PoP "CPU address", same as cpu_index */
     uint64_t cpuid;
 
     uint64_t tod_offset;
@@ -194,7 +194,6 @@ struct S390CPU {
     /*< public >*/
 
     CPUS390XState env;
-    int64_t id;
     S390CPUModel *model;
     /* needed for live migration */
     void *irqstate;
@@ -690,7 +689,7 @@ const char *s390_default_cpu_model_name(void);
 
 /* helper.c */
 #define cpu_init(cpu_model) cpu_generic_init(TYPE_S390_CPU, cpu_model)
-S390CPU *s390x_new_cpu(const char *cpu_model, int64_t id, Error **errp);
+S390CPU *s390x_new_cpu(const char *cpu_model, uint32_t core_id, Error **errp);
 /* you can call this signal handler from your SIGBUS and SIGSEGV
    signal handlers to inform the virtual CPU of exceptions. non zero
    is returned if the signal was handled by the virtual CPU.  */
target/s390x/cpu_models.c +1 -1
index 18cbf91d9c..8e20e7637b 100644
@@ -915,7 +915,7 @@ void s390_realize_cpu_model(CPUState *cs, Error **errp)
     cpu->env.cpuid = s390_cpuid_from_cpu_model(cpu->model);
     if (tcg_enabled()) {
         /* basic mode, write the cpu address into the first 4 bit of the ID */
-        cpu->env.cpuid = deposit64(cpu->env.cpuid, 54, 4, cpu->env.cpu_num);
+        cpu->env.cpuid = deposit64(cpu->env.cpuid, 54, 4, cpu->env.core_id);
     }
 }
 
target/s390x/excp_helper.c +1 -1
index 14d3160e92..470cf8f5bc 100644
@@ -250,7 +250,7 @@ static void do_ext_interrupt(CPUS390XState *env)
     lowcore->ext_params2 = cpu_to_be64(q->param64);
     lowcore->external_old_psw.mask = cpu_to_be64(get_psw_mask(env));
     lowcore->external_old_psw.addr = cpu_to_be64(env->psw.addr);
-    lowcore->cpu_addr = cpu_to_be16(env->cpu_num | VIRTIO_SUBCODE_64);
+    lowcore->cpu_addr = cpu_to_be16(env->core_id | VIRTIO_SUBCODE_64);
     mask = be64_to_cpu(lowcore->external_new_psw.mask);
     addr = be64_to_cpu(lowcore->external_new_psw.addr);
 
target/s390x/helper.c +2 -2
index ba29504476..dfb24ef5b2 100644
@@ -104,7 +104,7 @@ S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp)
     return S390_CPU(CPU(object_new(typename)));
 }
 
-S390CPU *s390x_new_cpu(const char *cpu_model, int64_t id, Error **errp)
+S390CPU *s390x_new_cpu(const char *cpu_model, uint32_t core_id, Error **errp)
 {
     S390CPU *cpu;
     Error *err = NULL;
@@ -114,7 +114,7 @@ S390CPU *s390x_new_cpu(const char *cpu_model, int64_t id, Error **errp)
         goto out;
     }
 
-    object_property_set_int(OBJECT(cpu), id, "id", &err);
+    object_property_set_int(OBJECT(cpu), core_id, "core-id", &err);
     if (err != NULL) {
         goto out;
     }
target/s390x/misc_helper.c +2 -2
index f3624d75eb..293fc8428a 100644
@@ -232,7 +232,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
             /* XXX make different for different CPUs? */
             ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
             ebcdic_put(sysib.plant, "QEMU", 4);
-            stw_p(&sysib.cpu_addr, env->cpu_num);
+            stw_p(&sysib.cpu_addr, env->core_id);
             cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
         } else if ((sel1 == 2) && (sel2 == 2)) {
             /* Basic Machine CPUs */
@@ -260,7 +260,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
                 /* XXX make different for different CPUs? */
                 ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
                 ebcdic_put(sysib.plant, "QEMU", 4);
-                stw_p(&sysib.cpu_addr, env->cpu_num);
+                stw_p(&sysib.cpu_addr, env->core_id);
                 stw_p(&sysib.cpu_id, 0);
                 cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
             } else if ((sel1 == 2) && (sel2 == 2)) {
target/s390x/translate.c +1 -4
index 909b12818d..5abd34fb34 100644
@@ -3823,10 +3823,7 @@ static ExitStatus op_ssm(DisasContext *s, DisasOps *o)
 static ExitStatus op_stap(DisasContext *s, DisasOps *o)
 {
     check_privileged(s);
-    /* ??? Surely cpu address != cpu number.  In any case the previous
-       version of this stored more than the required half-word, so it
-       is unlikely this has ever been tested.  */
-    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, cpu_num));
+    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, core_id));
     return NO_EXIT;
 }
 
Signature · 1 line
2.13.5
#20 lore raw

Re: [Qemu-devel] [PATCH v4 13/21] target/s390x: use "core-id" for cpu number/address/id handling

Quoted 8 lines · On Mon, 11 Sep 2017 17:21:42 +0200 David Hildenbrand <[email protected]> wrote:

Some time ago we discussed that using "id" as property name is not the right thing to do, as it is a reserved property for other devices and will not work with device_add.

Switch to the term "core-id" instead, and use it as an equivalent to "CPU address" mentioned in the PoP. There is no such thing as cpu number, so rename env.cpu_num to env.core_id. We use "core-id" as this is the common term to use for device_add later on (x86 and ppc).

is there possibility that later The core (something that contains threads) would appear/exist in real hw?
(my concern here is that we would have to use some other name for it as renaming of already shipped public property name would be not an option)

Quoted 18 lines

We can get rid of cpu->id now. Keep cpu_index and env->core_id in sync. cpu_index was already implicitly used by e.g. cpu_exists(), so keeping both in sync seems to be the right thing to do.

cpu_index will now no longer automatically get set via cpu_exec_realizefn(). For now, we were lucky that both implicitly stayed in sync.

Our new cpu property "core-id" can be a static property. Range checks can be avoided by using the correct type and the "setting after realized" check is done implicitly.

device_add will later need the reserved "id" property. Hotplugging a CPU on s390x will then be: "device_add host-s390-cpu,id=cpu2,core-id=2".

---

[...]

Quoted 27 lines
target/s390x/misc_helper.c +2 -2
index f3624d75eb..293fc8428a 100644
@@ -232,7 +232,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
             /* XXX make different for different CPUs? */
             ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
             ebcdic_put(sysib.plant, "QEMU", 4);
-            stw_p(&sysib.cpu_addr, env->cpu_num);
+            stw_p(&sysib.cpu_addr, env->core_id);
             cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
         } else if ((sel1 == 2) && (sel2 == 2)) {
             /* Basic Machine CPUs */
@@ -260,7 +260,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
                 /* XXX make different for different CPUs? */
                 ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
                 ebcdic_put(sysib.plant, "QEMU", 4);
-                stw_p(&sysib.cpu_addr, env->cpu_num);
+                stw_p(&sysib.cpu_addr, env->core_id);
                 stw_p(&sysib.cpu_id, 0);
                 cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
             } else if ((sel1 == 2) && (sel2 == 2)) {
target/s390x/translate.c +0 -0
index 909b12818d..5abd34fb34 100644

target/s390x/translate.c static ExitStatus op_ssm(DisasContext *s, DisasOps *o) · line 3828

Quoted 10 lines
target/s390x/translate.c +1 -4
@@ -3823,10 +3823,7 @@ static ExitStatus op_ssm(DisasContext *s, DisasOps *o)
 static ExitStatus op_stap(DisasContext *s, DisasOps *o)
 {
     check_privileged(s);
-    /* ??? Surely cpu address != cpu number.  In any case the previous
-       version of this stored more than the required half-word, so it
-       is unlikely this has ever been tested.  */
-    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, cpu_num));
+    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, core_id));
     return NO_EXIT;
 }

I see core_id is used in several instructions,
does it really have any influence on code executed by *-user target?

#21 lore raw

Re: [Qemu-devel] [PATCH v4 13/21] target/s390x: use "core-id" for cpu number/address/id handling

Quoted 7 lines · Igor Mammedov
Quoted 4 lines · On Mon, 11 Sep 2017 17:21:42 +0200 David Hildenbrand <[email protected]> wrote:

Some time ago we discussed that using "id" as property name is not the right thing to do, as it is a reserved property for other devices and will not work with device_add.

Quoted 8 lines
Quoted 4 lines

Switch to the term "core-id" instead, and use it as an equivalent to "CPU address" mentioned in the PoP. There is no such thing as cpu number, so rename env.cpu_num to env.core_id. We use "core-id" as this is the common term to use for device_add later on (x86 and ppc).

is there possibility that later The core (something that contains threads) would appear/exist in real hw?
(my concern here is that we would have to use some other name for it as renaming of already shipped public property name would be not an option)

There is the possibility (s390x has SMP support starting with z13), but it is really, really unlikely for KVM. There would be the chance of implementing this somewhen in the future for TCG (although I also doubt this will happen in the near future).

If so, I think there will only be one solution: a new machine type.

Faking threads now would be just plain wrong. So I think this should just be fine for now.

[...]

Quoted 31 lines
Quoted 31 lines
target/s390x/misc_helper.c +2 -2
index f3624d75eb..293fc8428a 100644
@@ -232,7 +232,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
             /* XXX make different for different CPUs? */
             ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
             ebcdic_put(sysib.plant, "QEMU", 4);
-            stw_p(&sysib.cpu_addr, env->cpu_num);
+            stw_p(&sysib.cpu_addr, env->core_id);
             cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
         } else if ((sel1 == 2) && (sel2 == 2)) {
             /* Basic Machine CPUs */
@@ -260,7 +260,7 @@ uint32_t HELPER(stsi)(CPUS390XState *env, uint64_t a0,
                 /* XXX make different for different CPUs? */
                 ebcdic_put(sysib.sequence, "QEMUQEMUQEMUQEMU", 16);
                 ebcdic_put(sysib.plant, "QEMU", 4);
-                stw_p(&sysib.cpu_addr, env->cpu_num);
+                stw_p(&sysib.cpu_addr, env->core_id);
                 stw_p(&sysib.cpu_id, 0);
                 cpu_physical_memory_write(a0, &sysib, sizeof(sysib));
             } else if ((sel1 == 2) && (sel2 == 2)) {
target/s390x/translate.c +0 -1
index 909b12818d..5abd34fb34 100644
@@ -3823,10 +3823,7 @@ static ExitStatus op_ssm(DisasContext *s, DisasOps *o)
 static ExitStatus op_stap(DisasContext *s, DisasOps *o)
 {
     check_privileged(s);
-    /* ??? Surely cpu address != cpu number.  In any case the previous
Quoted 9 lines

target/s390x/translate.c static ExitStatus op_ssm(DisasContext *s, DisasOps *o) · line 3828

Quoted 6 lines
target/s390x/translate.c +1 -3
-       version of this stored more than the required half-word, so it
-       is unlikely this has ever been tested.  */
-    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, cpu_num));
+    tcg_gen_ld32u_i64(o->out, cpu_env, offsetof(CPUS390XState, core_id));
     return NO_EXIT;
 }

I see core_id is used in several instructions,
does it really have any influence on code executed by *-user target?

Nope, these should all be privileged instructions and therefore not relevant for -user targets.

Signature · 3 lines
Thanks,

David
#22 lore raw

PATCH v4 14/21 target/s390x: rename next_cpu_id to next_core_id

In reply to David Hildenbrand

Adapt to the new term "core_id". While at it, fix the type and drop the initialization to 0 (which is superfluous).

---
 target/s390x/cpu-qom.h |  2 +-
 target/s390x/cpu.c     | 11 +++++------
 2 files changed, 6 insertions(+), 7 deletions(-)
target/s390x/cpu-qom.h +1 -1
index 2435cd8390..2e446fab51 100644
@@ -54,7 +54,7 @@ typedef struct S390CPUClass {
     bool is_migration_safe;
     const char *desc;
 
-    int64_t next_cpu_id;
+    uint32_t next_core_id;
 
     DeviceRealize parent_realize;
     void (*parent_reset)(CPUState *cpu);
target/s390x/cpu.c +5 -6
index 87ebbe5b28..8c1c644057 100644
@@ -198,7 +198,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
     }
 #else
     /* implicitly set for linux-user only */
-    cpu->env.core_id = scc->next_cpu_id;
+    cpu->env.core_id = scc->next_core_id;
 #endif
 
     if (cpu_exists(cpu->env.core_id)) {
@@ -206,10 +206,10 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
                    ", it already exists", cpu->env.core_id);
         goto out;
     }
-    if (cpu->env.core_id != scc->next_cpu_id) {
+    if (cpu->env.core_id != scc->next_core_id) {
         error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
-                   ", the next available core-id is %" PRIi64, cpu->env.core_id,
-                   scc->next_cpu_id);
+                   ", the next available core-id is %" PRIu32, cpu->env.core_id,
+                   scc->next_core_id);
         goto out;
     }
 
@@ -219,7 +219,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
     if (err != NULL) {
         goto out;
     }
-    scc->next_cpu_id++;
+    scc->next_core_id++;
 
 #if !defined(CONFIG_USER_ONLY)
     qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
@@ -464,7 +464,6 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
     CPUClass *cc = CPU_CLASS(scc);
     DeviceClass *dc = DEVICE_CLASS(oc);
 
-    scc->next_cpu_id = 0;
     scc->parent_realize = dc->realize;
     dc->realize = s390_cpu_realizefn;
     dc->props = s390x_cpu_properties;
Signature · 1 line
2.13.5
#23 lore raw

Re: [Qemu-devel] [PATCH v4 14/21] target/s390x: rename next_cpu_id to next_core_id

Quoted 15 lines · On Mon, 11 Sep 2017 17:21:43 +0200 David Hildenbrand <[email protected]> wrote:

Adapt to the new term "core_id". While at it, fix the type and drop the initialization to 0 (which is superfluous).

---
 target/s390x/cpu-qom.h |  2 +-
 target/s390x/cpu.c     | 11 +++++------
 2 files changed, 6 insertions(+), 7 deletions(-)
target/s390x/cpu-qom.h +0 -0
index 2435cd8390..2e446fab51 100644

target/s390x/cpu-qom.h typedef struct S390CPUClass { · line 57

Quoted 5 lines
target/s390x/cpu-qom.h +1 -1
@@ -54,7 +54,7 @@ typedef struct S390CPUClass {
     bool is_migration_safe;
     const char *desc;
 
-    int64_t next_cpu_id;
+    uint32_t next_core_id;

is it possible to hotplug cpus in out of order in real hw?

Quoted 47 lines
target/s390x/cpu-qom.h +0 -0
     DeviceRealize parent_realize;
     void (*parent_reset)(CPUState *cpu);
target/s390x/cpu.c +5 -6
index 87ebbe5b28..8c1c644057 100644
@@ -198,7 +198,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
     }
 #else
     /* implicitly set for linux-user only */
-    cpu->env.core_id = scc->next_cpu_id;
+    cpu->env.core_id = scc->next_core_id;
 #endif
 
     if (cpu_exists(cpu->env.core_id)) {
@@ -206,10 +206,10 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
                    ", it already exists", cpu->env.core_id);
         goto out;
     }
-    if (cpu->env.core_id != scc->next_cpu_id) {
+    if (cpu->env.core_id != scc->next_core_id) {
         error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
-                   ", the next available core-id is %" PRIi64, cpu->env.core_id,
-                   scc->next_cpu_id);
+                   ", the next available core-id is %" PRIu32, cpu->env.core_id,
+                   scc->next_core_id);
         goto out;
     }
 
@@ -219,7 +219,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
     if (err != NULL) {
         goto out;
     }
-    scc->next_cpu_id++;
+    scc->next_core_id++;
 
 #if !defined(CONFIG_USER_ONLY)
     qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
@@ -464,7 +464,6 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
     CPUClass *cc = CPU_CLASS(scc);
     DeviceClass *dc = DEVICE_CLASS(oc);
 
-    scc->next_cpu_id = 0;
     scc->parent_realize = dc->realize;
     dc->realize = s390_cpu_realizefn;
     dc->props = s390x_cpu_properties;
#24 lore raw

Re: [Qemu-devel] [PATCH v4 14/21] target/s390x: rename next_cpu_id to next_core_id

Quoted 21 lines · Igor Mammedov
Quoted 18 lines · On Mon, 11 Sep 2017 17:21:43 +0200 David Hildenbrand <[email protected]> wrote:

Adapt to the new term "core_id". While at it, fix the type and drop the initialization to 0 (which is superfluous).

---
 target/s390x/cpu-qom.h |  2 +-
 target/s390x/cpu.c     | 11 +++++------
 2 files changed, 6 insertions(+), 7 deletions(-)
target/s390x/cpu-qom.h +0 -0
index 2435cd8390..2e446fab51 100644
@@ -54,7 +54,7 @@ typedef struct S390CPUClass {
     bool is_migration_safe;
     const char *desc;
 
Quoted 3 lines

target/s390x/cpu-qom.h typedef struct S390CPUClass { · line 57

Quoted 2 lines
target/s390x/cpu-qom.h +1 -1
-    int64_t next_cpu_id;
+    uint32_t next_core_id;

is it possible to hotplug cpus in out of order in real hw?

Yes, at least under z/VM. See last two patches in this series.

Signature · 3 lines
Thanks,

David
#25 lore raw

PATCH v4 15/21 s390x: print CPU definitions in sorted order

In reply to David Hildenbrand

Other architectures provide nicely sorted lists, let's do it similarly on s390x.

While at it, clean up the code we have to touch either way.

---
 target/s390x/cpu_models.c | 56 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 41 insertions(+), 15 deletions(-)
target/s390x/cpu_models.c +41 -15
index 8e20e7637b..c295e641e6 100644
@@ -270,16 +270,11 @@ const S390CPUDef *s390_find_cpu_def(uint16_t type, uint8_t gen, uint8_t ec_ga,
     return last_compatible;
 }
 
-struct S390PrintCpuListInfo {
-    FILE *f;
-    fprintf_function print;
-};
-
-static void print_cpu_model_list(ObjectClass *klass, void *opaque)
+static void s390_print_cpu_model_list_entry(gpointer data, gpointer user_data)
 {
-    struct S390PrintCpuListInfo *info = opaque;
-    S390CPUClass *scc = S390_CPU_CLASS(klass);
-    char *name = g_strdup(object_class_get_name(klass));
+    CPUListState *s = user_data;
+    const S390CPUClass *scc = S390_CPU_CLASS((ObjectClass *)data);
+    char *name = g_strdup(object_class_get_name((ObjectClass *)data));
     const char *details = "";
 
     if (scc->is_static) {
@@ -290,21 +285,52 @@ static void print_cpu_model_list(ObjectClass *klass, void *opaque)
 
     /* strip off the -s390-cpu */
     g_strrstr(name, "-" TYPE_S390_CPU)[0] = 0;
-    (*info->print)(info->f, "s390 %-15s %-35s %s\n", name, scc->desc,
-                   details);
+    (*s->cpu_fprintf)(s->file, "s390 %-15s %-35s %s\n", name, scc->desc,
+                      details);
     g_free(name);
 }
 
+static gint s390_cpu_list_compare(gconstpointer a, gconstpointer b)
+{
+    const S390CPUClass *cc_a = S390_CPU_CLASS((ObjectClass *)a);
+    const S390CPUClass *cc_b = S390_CPU_CLASS((ObjectClass *)b);
+    const char *name_a = object_class_get_name((ObjectClass *)a);
+    const char *name_b = object_class_get_name((ObjectClass *)b);
+
+    /* move qemu and host to the top of the list, qemu first, host second */
+    if (name_a[0] == 'q') {
+        return -1;
+    } else if (name_b[0] == 'q') {
+        return 1;
+    } else if (name_a[0] == 'h') {
+        return -1;
+    } else if (name_b[0] == 'h') {
+        return 1;
+    }
+
+    /* keep the same order we have in our table (sorted by release date) */
+    if (cc_a->cpu_def != cc_b->cpu_def) {
+        return cc_a->cpu_def - cc_b->cpu_def;
+    }
+
+    /* exact same definition - list base model first */
+    return cc_a->is_static ? -1 : 1;
+}
+
 void s390_cpu_list(FILE *f, fprintf_function print)
 {
-    struct S390PrintCpuListInfo info = {
-        .f = f,
-        .print = print,
+    CPUListState s = {
+        .file = f,
+        .cpu_fprintf = print,
     };
     S390FeatGroup group;
     S390Feat feat;
+    GSList *list;
 
-    object_class_foreach(print_cpu_model_list, TYPE_S390_CPU, false, &info);
+    list = object_class_get_list(TYPE_S390_CPU, false);
+    list = g_slist_sort(list, s390_cpu_list_compare);
+    g_slist_foreach(list, s390_print_cpu_model_list_entry, &s);
+    g_slist_free(list);
 
     (*print)(f, "\nRecognized feature flags:\n");
     for (feat = 0; feat < S390_FEAT_MAX; feat++) {
Signature · 1 line
2.13.5
Acked-by on v4 15/21
#26 lore raw

Re: [Qemu-devel] [PATCH v4 15/21] s390x: print CPU definitions in sorted order

Quoted 6 lines · David Hildenbrand

Other architectures provide nicely sorted lists, let's do it similarly on s390x.

While at it, clean up the code we have to touch either way.

looks much nicer now, with the most important ones (new ones) still on screen.

Quoted 89 lines
---
 target/s390x/cpu_models.c | 56 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 41 insertions(+), 15 deletions(-)
target/s390x/cpu_models.c +41 -15
index 8e20e7637b..c295e641e6 100644
@@ -270,16 +270,11 @@ const S390CPUDef *s390_find_cpu_def(uint16_t type, uint8_t gen, uint8_t ec_ga,
     return last_compatible;
 }
 
-struct S390PrintCpuListInfo {
-    FILE *f;
-    fprintf_function print;
-};
-
-static void print_cpu_model_list(ObjectClass *klass, void *opaque)
+static void s390_print_cpu_model_list_entry(gpointer data, gpointer user_data)
 {
-    struct S390PrintCpuListInfo *info = opaque;
-    S390CPUClass *scc = S390_CPU_CLASS(klass);
-    char *name = g_strdup(object_class_get_name(klass));
+    CPUListState *s = user_data;
+    const S390CPUClass *scc = S390_CPU_CLASS((ObjectClass *)data);
+    char *name = g_strdup(object_class_get_name((ObjectClass *)data));
     const char *details = "";
 
     if (scc->is_static) {
@@ -290,21 +285,52 @@ static void print_cpu_model_list(ObjectClass *klass, void *opaque)
 
     /* strip off the -s390-cpu */
     g_strrstr(name, "-" TYPE_S390_CPU)[0] = 0;
-    (*info->print)(info->f, "s390 %-15s %-35s %s\n", name, scc->desc,
-                   details);
+    (*s->cpu_fprintf)(s->file, "s390 %-15s %-35s %s\n", name, scc->desc,
+                      details);
     g_free(name);
 }
 
+static gint s390_cpu_list_compare(gconstpointer a, gconstpointer b)
+{
+    const S390CPUClass *cc_a = S390_CPU_CLASS((ObjectClass *)a);
+    const S390CPUClass *cc_b = S390_CPU_CLASS((ObjectClass *)b);
+    const char *name_a = object_class_get_name((ObjectClass *)a);
+    const char *name_b = object_class_get_name((ObjectClass *)b);
+
+    /* move qemu and host to the top of the list, qemu first, host second */
+    if (name_a[0] == 'q') {
+        return -1;
+    } else if (name_b[0] == 'q') {
+        return 1;
+    } else if (name_a[0] == 'h') {
+        return -1;
+    } else if (name_b[0] == 'h') {
+        return 1;
+    }
+
+    /* keep the same order we have in our table (sorted by release date) */
+    if (cc_a->cpu_def != cc_b->cpu_def) {
+        return cc_a->cpu_def - cc_b->cpu_def;
+    }
+
+    /* exact same definition - list base model first */
+    return cc_a->is_static ? -1 : 1;
+}
+
 void s390_cpu_list(FILE *f, fprintf_function print)
 {
-    struct S390PrintCpuListInfo info = {
-        .f = f,
-        .print = print,
+    CPUListState s = {
+        .file = f,
+        .cpu_fprintf = print,
     };
     S390FeatGroup group;
     S390Feat feat;
+    GSList *list;
 
-    object_class_foreach(print_cpu_model_list, TYPE_S390_CPU, false, &info);
+    list = object_class_get_list(TYPE_S390_CPU, false);
+    list = g_slist_sort(list, s390_cpu_list_compare);
+    g_slist_foreach(list, s390_print_cpu_model_list_entry, &s);
+    g_slist_free(list);
 
     (*print)(f, "\nRecognized feature flags:\n");
     for (feat = 0; feat < S390_FEAT_MAX; feat++) {
#27 lore raw

PATCH v4 16/21 s390x: allow cpu hotplug via device_add

In reply to David Hildenbrand

E.g. the following now works:

    device_add host-s390-cpu,id=cpu1,core-id=1

The system will perform the same checks as when using cpu_add:
- If the core_id is already in use
- If the next sequential core_id isn't used
- If core-id >= max_cpu is specified

In addition, mixed CPU models are checked. E.g. if starting with -cpu host and trying to hotplug "qemu-s390-cpu":

    "Mixed CPU models are not supported on s390x."
---
 target/s390x/cpu.c | 1 +
 1 file changed, 1 insertion(+)
target/s390x/cpu.c +1 -0
index 8c1c644057..5724dffb88 100644
@@ -467,6 +467,7 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
     scc->parent_realize = dc->realize;
     dc->realize = s390_cpu_realizefn;
     dc->props = s390x_cpu_properties;
+    dc->user_creatable = true;
 
     scc->parent_reset = cc->reset;
 #if !defined(CONFIG_USER_ONLY)
Signature · 1 line
2.13.5
#28 lore raw

PATCH v4 17/21 s390x: CPU hot unplug via device_del cannot work for now

In reply to David Hildenbrand

device_del on a CPU will currently do nothing. Let's emmit an error telling that this is will currently not work (there is no architecture support on s390x). Error message copied from ppc.

(qemu) device_del cpu1
device_del cpu1
CPU hot unplug not supported on this machine

---
 hw/s390x/s390-virtio-ccw.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
hw/s390x/s390-virtio-ccw.c +10 -0
index 2086eb6ca6..120f82e339 100644
@@ -341,6 +341,15 @@ static void s390_machine_device_plug(HotplugHandler *hotplug_dev,
     }
 }
 
+static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev,
+                                               DeviceState *dev, Error **errp)
+{
+    if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
+        error_setg(errp, "CPU hot unplug not supported on this machine");
+        return;
+    }
+}
+
 static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
                                                 DeviceState *dev)
 {
@@ -390,6 +399,7 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     mc->max_cpus = 248;
     mc->get_hotplug_handler = s390_get_hotplug_handler;
     hc->plug = s390_machine_device_plug;
+    hc->unplug_request = s390_machine_device_unplug_request;
     nc->nmi_monitor_handler = s390_nmi;
 }
 
Signature · 1 line
2.13.5
#29 lore raw

PATCH v4 18/21 s390x: implement query-hotpluggable-cpus

In reply to David Hildenbrand

CPU hotplug is only possible on a per core basis on s390x.

As we now have ms->possible_cpus, we can get rid of the global variable cpu_states.

While rewriting s390_cpu_addr2state() completely to be based on possible_cpus, move it to cpu.c, as it is independent of the virtio-ccw machine.

---
 hw/s390x/s390-virtio-ccw.c | 87 +++++++++++++++++++++++++++++-----------------
 qapi-schema.json           | 16 +++++++++
 target/s390x/cpu.c         | 17 +++++++++
 target/s390x/cpu.h         |  5 +--
 4 files changed, 89 insertions(+), 36 deletions(-)
hw/s390x/s390-virtio-ccw.c +55 -32
index 120f82e339..0e10a4c73a 100644
@@ -36,24 +36,12 @@
 #include "qapi/qmp/qerror.h"
 #include "hw/nmi.h"
 
-static S390CPU **cpu_states;
-
-S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
-{
-    if (cpu_addr >= max_cpus) {
-        return NULL;
-    }
-
-    /* Fast lookup via CPU ID */
-    return cpu_states[cpu_addr];
-}
-
 /* #define S390_TCG_SMP_SUPPORT */
 
 static void s390_init_cpus(MachineState *machine)
 {
+    MachineClass *mc = MACHINE_GET_CLASS(machine);
     int i;
-    gchar *name;
 
     if (machine->cpu_model == NULL) {
         machine->cpu_model = s390_default_cpu_model_name();
@@ -66,17 +54,8 @@ static void s390_init_cpus(MachineState *machine)
     }
 #endif
 
-    cpu_states = g_new0(S390CPU *, max_cpus);
-
-    for (i = 0; i < max_cpus; i++) {
-        name = g_strdup_printf("cpu[%i]", i);
-        object_property_add_link(OBJECT(machine), name, TYPE_S390_CPU,
-                                 (Object **) &cpu_states[i],
-                                 object_property_allow_set_link,
-                                 OBJ_PROP_LINK_UNREF_ON_RELEASE,
-                                 &error_abort);
-        g_free(name);
-    }
+    /* initialize possible_cpus */
+    mc->possible_cpu_arch_ids(machine);
 
     for (i = 0; i < smp_cpus; i++) {
         s390x_new_cpu(machine->cpu_model, i, &error_fatal);
@@ -307,17 +286,14 @@ static void ccw_init(MachineState *machine)
     register_savevm_live(NULL, "todclock", 0, 1, &savevm_gtod, NULL);
 }
 
-static void s390_cpu_plug(HotplugHandler *hotplug_dev,
-                        DeviceState *dev, Error **errp)
+static void s390_cpu_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                          Error **errp)
 {
-    gchar *name;
+    MachineState *ms = MACHINE(hotplug_dev);
     S390CPU *cpu = S390_CPU(dev);
-    CPUState *cs = CPU(dev);
 
-    name = g_strdup_printf("cpu[%i]", cpu->env.core_id);
-    object_property_set_link(OBJECT(hotplug_dev), OBJECT(cs), name,
-                             errp);
-    g_free(name);
+    g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu);
+    ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev);
 }
 
 static void s390_machine_reset(void)
@@ -350,6 +326,50 @@ static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev,
     }
 }
 
+static CPUArchId *s390_find_cpu_slot(MachineState *ms, uint32_t core_id,
+                                     int *idx)
+{
+    if (core_id >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    /* core_id corresponds to the index */
+    if (idx) {
+        *idx = core_id;
+    }
+    return &ms->possible_cpus->cpus[core_id];
+}
+
+static CpuInstanceProperties s390_cpu_index_to_props(MachineState *machine,
+                                                     unsigned cpu_index)
+{
+    CPUArchId *slot = s390_find_cpu_slot(machine, cpu_index, NULL);
+
+    assert(slot);
+    return slot->props;
+}
+
+static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms)
+{
+    int i;
+
+    if (ms->possible_cpus) {
+        g_assert(ms->possible_cpus && ms->possible_cpus->len == max_cpus);
+        return ms->possible_cpus;
+    }
+
+    ms->possible_cpus = g_malloc0(sizeof(CPUArchIdList) +
+                                  sizeof(CPUArchId) * max_cpus);
+    ms->possible_cpus->len = max_cpus;
+    for (i = 0; i < ms->possible_cpus->len; i++) {
+        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;
+    }
+
+    return ms->possible_cpus;
+}
+
 static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
                                                 DeviceState *dev)
 {
@@ -397,7 +417,10 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     mc->no_sdcard = 1;
     mc->use_sclp = 1;
     mc->max_cpus = 248;
+    mc->has_hotpluggable_cpus = true;
     mc->get_hotplug_handler = s390_get_hotplug_handler;
+    mc->cpu_index_to_instance_props = s390_cpu_index_to_props;
+    mc->possible_cpu_arch_ids = s390_possible_cpu_arch_ids;
     hc->plug = s390_machine_device_plug;
     hc->unplug_request = s390_machine_device_unplug_request;
     nc->nmi_monitor_handler = s390_nmi;
qapi-schema.json +16 -0
index f3af2cb851..79e9f85404 100644
@@ -3121,6 +3121,22 @@
 #      }
 #    ]}
 #
+# For s390x-virtio-ccw machine type started with -smp 1,maxcpus=2 -cpu qemu
+# (Since: 2.11):
+#
+# -> { "execute": "query-hotpluggable-cpus" }
+# <- {"return": [
+#      {
+#         "type": "qemu-s390-cpu", "vcpus-count": 1,
+#         "props": { "core-id": 1 }
+#      },
+#      {
+#         "qom-path": "/machine/unattached/device[0]",
+#         "type": "qemu-s390-cpu", "vcpus-count": 1,
+#         "props": { "core-id": 0 }
+#      }
+#    ]}
+#
 ##
 { 'command': 'query-hotpluggable-cpus', 'returns': ['HotpluggableCPU'] }
 
target/s390x/cpu.c +17 -0
index 5724dffb88..7f174f90a4 100644
@@ -38,6 +38,7 @@
 #include "exec/exec-all.h"
 #include "hw/qdev-properties.h"
 #ifndef CONFIG_USER_ONLY
+#include "hw/boards.h"
 #include "hw/hw.h"
 #include "sysemu/arch_init.h"
 #include "sysemu/sysemu.h"
@@ -446,6 +447,22 @@ void s390_enable_css_support(S390CPU *cpu)
         kvm_s390_enable_css_support(cpu);
     }
 }
+
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
+{
+    static MachineState *ms;
+
+    if (!ms) {
+        ms = MACHINE(qdev_get_machine());
+        g_assert(ms->possible_cpus);
+    }
+
+    /* CPU address corresponds to the core_id and the index */
+    if (cpu_addr >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    return S390_CPU(ms->possible_cpus->cpus[cpu_addr].cpu);
+}
 #endif
 
 static gchar *s390_gdb_arch_name(CPUState *cs)
target/s390x/cpu.h +1 -4
index 1c8456fa57..5810079f48 100644
@@ -671,6 +671,7 @@ int s390_cpu_restart(S390CPU *cpu);
 void s390_enable_css_support(S390CPU *cpu);
 int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
                                 int vq, bool assign);
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
 #ifndef CONFIG_USER_ONLY
 unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu);
 #else
@@ -718,8 +719,4 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
         s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
 
-
-/* outside of target/s390x/ */
-S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
-
 #endif
Signature · 1 line
2.13.5
#30 lore raw

Re: [Qemu-devel] [PATCH v4 18/21] s390x: implement query-hotpluggable-cpus

Quoted 8 lines · On Mon, 11 Sep 2017 17:21:47 +0200 David Hildenbrand <[email protected]> wrote:

CPU hotplug is only possible on a per core basis on s390x.

As we now have ms->possible_cpus, we can get rid of the global variable cpu_states.

While rewriting s390_cpu_addr2state() completely to be based on possible_cpus, move it to cpu.c, as it is independent of the virtio-ccw machine.

I'd split patch on
1) introduce possible cpus
2) rewrite s390_cpu_addr2state() using #2

Quoted 87 lines
---
 hw/s390x/s390-virtio-ccw.c | 87 +++++++++++++++++++++++++++++-----------------
 qapi-schema.json           | 16 +++++++++
 target/s390x/cpu.c         | 17 +++++++++
 target/s390x/cpu.h         |  5 +--
 4 files changed, 89 insertions(+), 36 deletions(-)
hw/s390x/s390-virtio-ccw.c +10 -32
index 120f82e339..0e10a4c73a 100644
@@ -36,24 +36,12 @@
 #include "qapi/qmp/qerror.h"
 #include "hw/nmi.h"
 
-static S390CPU **cpu_states;
-
-S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
-{
-    if (cpu_addr >= max_cpus) {
-        return NULL;
-    }
-
-    /* Fast lookup via CPU ID */
-    return cpu_states[cpu_addr];
-}
-
 /* #define S390_TCG_SMP_SUPPORT */
 
 static void s390_init_cpus(MachineState *machine)
 {
+    MachineClass *mc = MACHINE_GET_CLASS(machine);
     int i;
-    gchar *name;
 
     if (machine->cpu_model == NULL) {
         machine->cpu_model = s390_default_cpu_model_name();
@@ -66,17 +54,8 @@ static void s390_init_cpus(MachineState *machine)
     }
 #endif
 
-    cpu_states = g_new0(S390CPU *, max_cpus);
-
-    for (i = 0; i < max_cpus; i++) {
-        name = g_strdup_printf("cpu[%i]", i);
-        object_property_add_link(OBJECT(machine), name, TYPE_S390_CPU,
-                                 (Object **) &cpu_states[i],
-                                 object_property_allow_set_link,
-                                 OBJ_PROP_LINK_UNREF_ON_RELEASE,
-                                 &error_abort);
-        g_free(name);
-    }
+    /* initialize possible_cpus */
+    mc->possible_cpu_arch_ids(machine);
 
     for (i = 0; i < smp_cpus; i++) {
         s390x_new_cpu(machine->cpu_model, i, &error_fatal);
@@ -307,17 +286,14 @@ static void ccw_init(MachineState *machine)
     register_savevm_live(NULL, "todclock", 0, 1, &savevm_gtod, NULL);
 }
 
-static void s390_cpu_plug(HotplugHandler *hotplug_dev,
-                        DeviceState *dev, Error **errp)
+static void s390_cpu_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                          Error **errp)
 {
-    gchar *name;
+    MachineState *ms = MACHINE(hotplug_dev);
     S390CPU *cpu = S390_CPU(dev);
-    CPUState *cs = CPU(dev);
 
-    name = g_strdup_printf("cpu[%i]", cpu->env.core_id);
-    object_property_set_link(OBJECT(hotplug_dev), OBJECT(cs), name,
-                             errp);
-    g_free(name);
+    g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu);
+    ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev);
 }
 
 static void s390_machine_reset(void)
@@ -350,6 +326,50 @@ static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev,
     }
 }
 
+static CPUArchId *s390_find_cpu_slot(MachineState *ms, uint32_t core_id,
+                                     int *idx)

hw/s390x/s390-virtio-ccw.c static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev, · line 340

Quoted 10 lines
hw/s390x/s390-virtio-ccw.c +10 -0
+{
+    if (core_id >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    /* core_id corresponds to the index */
+    if (idx) {
+        *idx = core_id;
+    }
+    return &ms->possible_cpus->cpus[core_id];
+}

it looks like cpu_index == core_id == idx in possible_cpus, is this helper really necessary?
(we have it in x86 because of possible not 1:1 mapping)

I'd drop it and just access array directly

Quoted 86 lines
hw/s390x/s390-virtio-ccw.c +35 -0
+
+static CpuInstanceProperties s390_cpu_index_to_props(MachineState *machine,
+                                                     unsigned cpu_index)
+{
+    CPUArchId *slot = s390_find_cpu_slot(machine, cpu_index, NULL);
+
+    assert(slot);
+    return slot->props;
+}
+
+static const CPUArchIdList *s390_possible_cpu_arch_ids(MachineState *ms)
+{
+    int i;
+
+    if (ms->possible_cpus) {
+        g_assert(ms->possible_cpus && ms->possible_cpus->len == max_cpus);
+        return ms->possible_cpus;
+    }
+
+    ms->possible_cpus = g_malloc0(sizeof(CPUArchIdList) +
+                                  sizeof(CPUArchId) * max_cpus);
+    ms->possible_cpus->len = max_cpus;
+    for (i = 0; i < ms->possible_cpus->len; i++) {
+        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;
+    }
+
+    return ms->possible_cpus;
+}
+
 static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
                                                 DeviceState *dev)
 {
@@ -397,7 +417,10 @@ static void ccw_machine_class_init(ObjectClass *oc, void *data)
     mc->no_sdcard = 1;
     mc->use_sclp = 1;
     mc->max_cpus = 248;
+    mc->has_hotpluggable_cpus = true;
     mc->get_hotplug_handler = s390_get_hotplug_handler;
+    mc->cpu_index_to_instance_props = s390_cpu_index_to_props;
+    mc->possible_cpu_arch_ids = s390_possible_cpu_arch_ids;
     hc->plug = s390_machine_device_plug;
     hc->unplug_request = s390_machine_device_unplug_request;
     nc->nmi_monitor_handler = s390_nmi;
qapi-schema.json +16 -0
index f3af2cb851..79e9f85404 100644
@@ -3121,6 +3121,22 @@
 #      }
 #    ]}
 #
+# For s390x-virtio-ccw machine type started with -smp 1,maxcpus=2 -cpu qemu
+# (Since: 2.11):
+#
+# -> { "execute": "query-hotpluggable-cpus" }
+# <- {"return": [
+#      {
+#         "type": "qemu-s390-cpu", "vcpus-count": 1,
+#         "props": { "core-id": 1 }
+#      },
+#      {
+#         "qom-path": "/machine/unattached/device[0]",
+#         "type": "qemu-s390-cpu", "vcpus-count": 1,
+#         "props": { "core-id": 0 }
+#      }
+#    ]}
+#
 ##
 { 'command': 'query-hotpluggable-cpus', 'returns': ['HotpluggableCPU'] }
 
target/s390x/cpu.c +1 -0
index 5724dffb88..7f174f90a4 100644
@@ -38,6 +38,7 @@
 #include "exec/exec-all.h"
 #include "hw/qdev-properties.h"
 #ifndef CONFIG_USER_ONLY
+#include "hw/boards.h"
 #include "hw/hw.h"
 #include "sysemu/arch_init.h"
 #include "sysemu/sysemu.h"

target/s390x/cpu.c void s390_enable_css_support(S390CPU *cpu) · line 452

Quoted 6 lines
target/s390x/cpu.c +3 -0
@@ -446,6 +447,22 @@ void s390_enable_css_support(S390CPU *cpu)
         kvm_s390_enable_css_support(cpu);
     }
 }
+
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
+{

target/cpu.c and cpu itself preferably shouldn't pull in
or depend on machine, so I'd keep s390_cpu_addr2state() where it's now or somewhere in board related files

Quoted 37 lines
target/s390x/cpu.c +13 -0
+    static MachineState *ms;
+
+    if (!ms) {
+        ms = MACHINE(qdev_get_machine());
+        g_assert(ms->possible_cpus);
+    }
+
+    /* CPU address corresponds to the core_id and the index */
+    if (cpu_addr >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    return S390_CPU(ms->possible_cpus->cpus[cpu_addr].cpu);
+}
 #endif
 
 static gchar *s390_gdb_arch_name(CPUState *cs)
target/s390x/cpu.h +1 -4
index 1c8456fa57..5810079f48 100644
@@ -671,6 +671,7 @@ int s390_cpu_restart(S390CPU *cpu);
 void s390_enable_css_support(S390CPU *cpu);
 int s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch_id,
                                 int vq, bool assign);
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
 #ifndef CONFIG_USER_ONLY
 unsigned int s390_cpu_set_state(uint8_t cpu_state, S390CPU *cpu);
 #else
@@ -718,8 +719,4 @@ int s390_cpu_virt_mem_rw(S390CPU *cpu, vaddr laddr, uint8_t ar, void *hostbuf,
 #define s390_cpu_virt_mem_check_write(cpu, laddr, ar, len)   \
         s390_cpu_virt_mem_rw(cpu, laddr, ar, NULL, len, true)
 
-
-/* outside of target/s390x/ */
-S390CPU *s390_cpu_addr2state(uint16_t cpu_addr);
-
 #endif
#31 lore raw

Re: [Qemu-devel] [PATCH v4 18/21] s390x: implement query-hotpluggable-cpus

Quoted 8 lines · Igor Mammedov
Quoted 5 lines · On Mon, 11 Sep 2017 17:21:47 +0200 David Hildenbrand <[email protected]> wrote:

CPU hotplug is only possible on a per core basis on s390x.

As we now have ms->possible_cpus, we can get rid of the global variable cpu_states.

Quoted 6 lines
Quoted 3 lines

While rewriting s390_cpu_addr2state() completely to be based on possible_cpus, move it to cpu.c, as it is independent of the virtio-ccw machine.

I'd split patch on
1) introduce possible cpus
2) rewrite s390_cpu_addr2state() using #2

Than I have to keep the global variable + setting it for one patch. Might not be worth the trouble. Will have a look.

[...]

Quoted 17 lines

hw/s390x/s390-virtio-ccw.c static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev, · line 340

Quoted 13 lines
hw/s390x/s390-virtio-ccw.c +12 -0
+static CPUArchId *s390_find_cpu_slot(MachineState *ms, uint32_t core_id,
+                                     int *idx)
+{
+    if (core_id >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    /* core_id corresponds to the index */
+    if (idx) {
+        *idx = core_id;
+    }
+    return &ms->possible_cpus->cpus[core_id];
+}

it looks like cpu_index == core_id == idx in possible_cpus, is this helper really necessary?
(we have it in x86 because of possible not 1:1 mapping)

Quoted 1 line

I'd drop it and just access array directly

Just kept this because the other architectures also have this. I can of course drop it. The nice thing about this helper is the comment :)

[...]

Quoted 7 lines

target/s390x/cpu.c void s390_enable_css_support(S390CPU *cpu) · line 452

Quoted 4 lines

}

target/s390x/cpu.c +3 -0
+
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
+{

target/cpu.c and cpu itself preferably shouldn't pull in
or depend on machine, so I'd keep s390_cpu_addr2state() where it's now or somewhere in board related files

Thomas requested this. I actually don't care., but it looks like a generic "get_cpu_by_arch_id" function. But I don't really want to go that additional path now. And also I don't want to move this back and forth.

Thomas, what's your opinion?

Thanks!

Signature · 3 lines
Thanks,

David
#32 lore raw

Re: [Qemu-devel] [PATCH v4 18/21] s390x: implement query-hotpluggable-cpus

Quoted 51 lines · David Hildenbrand
Quoted 8 lines · Igor Mammedov
Quoted 5 lines · On Mon, 11 Sep 2017 17:21:47 +0200 David Hildenbrand <[email protected]> wrote:

CPU hotplug is only possible on a per core basis on s390x.

As we now have ms->possible_cpus, we can get rid of the global variable cpu_states.

Quoted 6 lines
Quoted 3 lines

While rewriting s390_cpu_addr2state() completely to be based on possible_cpus, move it to cpu.c, as it is independent of the virtio-ccw machine.

I'd split patch on
1) introduce possible cpus
2) rewrite s390_cpu_addr2state() using #2

Than I have to keep the global variable + setting it for one patch. Might not be worth the trouble. Will have a look.

[...]

Quoted 17 lines

hw/s390x/s390-virtio-ccw.c static void s390_machine_device_unplug_request(HotplugHandler *hotplug_dev, · line 340

Quoted 13 lines
hw/s390x/s390-virtio-ccw.c +12 -0
+static CPUArchId *s390_find_cpu_slot(MachineState *ms, uint32_t core_id,
+                                     int *idx)
+{
+    if (core_id >= ms->possible_cpus->len) {
+        return NULL;
+    }
+    /* core_id corresponds to the index */
+    if (idx) {
+        *idx = core_id;
+    }
+    return &ms->possible_cpus->cpus[core_id];
+}

it looks like cpu_index == core_id == idx in possible_cpus, is this helper really necessary?
(we have it in x86 because of possible not 1:1 mapping)

Quoted 1 line

I'd drop it and just access array directly

Just kept this because the other architectures also have this. I can of course drop it. The nice thing about this helper is the comment :)

[...]

Quoted 7 lines

target/s390x/cpu.c void s390_enable_css_support(S390CPU *cpu) · line 452

Quoted 4 lines

}

target/s390x/cpu.c +3 -0
+
+S390CPU *s390_cpu_addr2state(uint16_t cpu_addr)
+{

target/cpu.c and cpu itself preferably shouldn't pull in
or depend on machine, so I'd keep s390_cpu_addr2state() where it's now or somewhere in board related files

Quoted 5 lines

Thomas requested this. I actually don't care., but it looks like a generic "get_cpu_by_arch_id" function. But I don't really want to go that additional path now. And also I don't want to move this back and forth.

Thomas, what's your opinion?

Hmm, since the new version uses MachineState now, it's maybe really better to leave it in the hw/s390x/ directory, I guess. Sorry for the inconvenience ...

Thomas

#33 lore raw

PATCH v4 19/21 s390x: get rid of cpu_s390x_create()

In reply to David Hildenbrand

Now that there is only one user of cpu_s390x_create() left, make cpu creation look like on x86.
- Perform the model/properties split and checks in s390_init_cpus()
- Parse features only once without having to remember if already parsed
- Pass only the typename to s390x_new_cpu()
- Use the typename of an existing CPU for hotplug via cpu-add

---
 hw/s390x/s390-virtio-ccw.c | 29 +++++++++++++++++++++++++++--
 target/s390x/cpu.h         |  2 +-
 target/s390x/helper.c      | 45 ++-------------------------------------------
 target/s390x/internal.h    |  1 -
 4 files changed, 30 insertions(+), 47 deletions(-)
hw/s390x/s390-virtio-ccw.c +27 -2
index 0e10a4c73a..10f6933fbd 100644
@@ -41,6 +41,10 @@
 static void s390_init_cpus(MachineState *machine)
 {
     MachineClass *mc = MACHINE_GET_CLASS(machine);
+    const char *typename;
+    gchar **model_pieces;
+    ObjectClass *oc;
+    CPUClass *cc;
     int i;
 
     if (machine->cpu_model == NULL) {
@@ -57,8 +61,25 @@ static void s390_init_cpus(MachineState *machine)
     /* initialize possible_cpus */
     mc->possible_cpu_arch_ids(machine);
 
+    model_pieces = g_strsplit(machine->cpu_model, ",", 2);
+    if (!model_pieces[0]) {
+        error_report("Invalid/empty CPU model name");
+        exit(1);
+    }
+
+    oc = cpu_class_by_name(TYPE_S390_CPU, model_pieces[0]);
+    if (!oc) {
+        error_report("Unable to find CPU definition: %s", model_pieces[0]);
+        exit(1);
+    }
+    typename = object_class_get_name(oc);
+    cc = CPU_CLASS(oc);
+    /* after parsing, properties will be applied to all *typename* instances */
+    cc->parse_features(typename, model_pieces[1], &error_fatal);
+    g_strfreev(model_pieces);
+
     for (i = 0; i < smp_cpus; i++) {
-        s390x_new_cpu(machine->cpu_model, i, &error_fatal);
+        s390x_new_cpu(typename, i, &error_fatal);
     }
 }
 
@@ -382,8 +403,12 @@ static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
 static void s390_hot_add_cpu(const int64_t id, Error **errp)
 {
     MachineState *machine = MACHINE(qdev_get_machine());
+    ObjectClass *oc;
+
+    g_assert(machine->possible_cpus->cpus[0].cpu);
+    oc = OBJECT_CLASS(CPU_GET_CLASS(machine->possible_cpus->cpus[0].cpu));
 
-    s390x_new_cpu(machine->cpu_model, id, errp);
+    s390x_new_cpu(object_class_get_name(oc), id, errp);
 }
 
 static void s390_nmi(NMIState *n, int cpu_index, Error **errp)
target/s390x/cpu.h +1 -1
index 5810079f48..56eccb0104 100644
@@ -690,7 +690,7 @@ const char *s390_default_cpu_model_name(void);
 
 /* helper.c */
 #define cpu_init(cpu_model) cpu_generic_init(TYPE_S390_CPU, cpu_model)
-S390CPU *s390x_new_cpu(const char *cpu_model, uint32_t core_id, Error **errp);
+S390CPU *s390x_new_cpu(const char *typename, uint32_t core_id, Error **errp);
 /* you can call this signal handler from your SIGBUS and SIGSEGV
    signal handlers to inform the virtual CPU of exceptions. non zero
    is returned if the signal was handled by the virtual CPU.  */
target/s390x/helper.c +2 -43

54 lines not on this page · raw message

target/s390x/internal.h +0 -1
index b4d3583b24..bc8f83129a 100644
@@ -337,7 +337,6 @@ uint64_t get_psw_mask(CPUS390XState *env);
 void s390_cpu_recompute_watchpoints(CPUState *cs);
 void s390x_tod_timer(void *opaque);
 void s390x_cpu_timer(void *opaque);
-S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp);
 void do_restart_interrupt(CPUS390XState *env);
 #ifndef CONFIG_USER_ONLY
 LowCore *cpu_map_lowcore(CPUS390XState *env);
Signature · 1 line
2.13.5
Acked-by on v4 19/21
#34 lore raw

Re: [Qemu-devel] [PATCH v4 19/21] s390x: get rid of cpu_s390x_create()

Quoted 8 lines · On Mon, 11 Sep 2017 17:21:48 +0200 David Hildenbrand <[email protected]> wrote:

Now that there is only one user of cpu_s390x_create() left, make cpu creation look like on x86.
- Perform the model/properties split and checks in s390_init_cpus()
- Parse features only once without having to remember if already parsed
- Pass only the typename to s390x_new_cpu()
- Use the typename of an existing CPU for hotplug via cpu-add

Quoted 147 lines
---
 hw/s390x/s390-virtio-ccw.c | 29 +++++++++++++++++++++++++++--
 target/s390x/cpu.h         |  2 +-
 target/s390x/helper.c      | 45 ++-------------------------------------------
 target/s390x/internal.h    |  1 -
 4 files changed, 30 insertions(+), 47 deletions(-)
hw/s390x/s390-virtio-ccw.c +27 -2
index 0e10a4c73a..10f6933fbd 100644
@@ -41,6 +41,10 @@
 static void s390_init_cpus(MachineState *machine)
 {
     MachineClass *mc = MACHINE_GET_CLASS(machine);
+    const char *typename;
+    gchar **model_pieces;
+    ObjectClass *oc;
+    CPUClass *cc;
     int i;
 
     if (machine->cpu_model == NULL) {
@@ -57,8 +61,25 @@ static void s390_init_cpus(MachineState *machine)
     /* initialize possible_cpus */
     mc->possible_cpu_arch_ids(machine);
 
+    model_pieces = g_strsplit(machine->cpu_model, ",", 2);
+    if (!model_pieces[0]) {
+        error_report("Invalid/empty CPU model name");
+        exit(1);
+    }
+
+    oc = cpu_class_by_name(TYPE_S390_CPU, model_pieces[0]);
+    if (!oc) {
+        error_report("Unable to find CPU definition: %s", model_pieces[0]);
+        exit(1);
+    }
+    typename = object_class_get_name(oc);
+    cc = CPU_CLASS(oc);
+    /* after parsing, properties will be applied to all *typename* instances */
+    cc->parse_features(typename, model_pieces[1], &error_fatal);
+    g_strfreev(model_pieces);
+
     for (i = 0; i < smp_cpus; i++) {
-        s390x_new_cpu(machine->cpu_model, i, &error_fatal);
+        s390x_new_cpu(typename, i, &error_fatal);
     }
 }
 
@@ -382,8 +403,12 @@ static HotplugHandler *s390_get_hotplug_handler(MachineState *machine,
 static void s390_hot_add_cpu(const int64_t id, Error **errp)
 {
     MachineState *machine = MACHINE(qdev_get_machine());
+    ObjectClass *oc;
+
+    g_assert(machine->possible_cpus->cpus[0].cpu);
+    oc = OBJECT_CLASS(CPU_GET_CLASS(machine->possible_cpus->cpus[0].cpu));
 
-    s390x_new_cpu(machine->cpu_model, id, errp);
+    s390x_new_cpu(object_class_get_name(oc), id, errp);
 }
 
 static void s390_nmi(NMIState *n, int cpu_index, Error **errp)
target/s390x/cpu.h +1 -1
index 5810079f48..56eccb0104 100644
@@ -690,7 +690,7 @@ const char *s390_default_cpu_model_name(void);
 
 /* helper.c */
 #define cpu_init(cpu_model) cpu_generic_init(TYPE_S390_CPU, cpu_model)
-S390CPU *s390x_new_cpu(const char *cpu_model, uint32_t core_id, Error **errp);
+S390CPU *s390x_new_cpu(const char *typename, uint32_t core_id, Error **errp);
 /* you can call this signal handler from your SIGBUS and SIGSEGV
    signal handlers to inform the virtual CPU of exceptions. non zero
    is returned if the signal was handled by the virtual CPU.  */
target/s390x/helper.c +2 -43
index dfb24ef5b2..97adbcc86d 100644
@@ -68,52 +68,11 @@ void s390x_cpu_timer(void *opaque)
 }
 #endif
 
-S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp)
+S390CPU *s390x_new_cpu(const char *typename, uint32_t core_id, Error **errp)
 {
-    static bool features_parsed;
-    char *name, *features;
-    const char *typename;
-    ObjectClass *oc;
-    CPUClass *cc;
-
-    name = g_strdup(cpu_model);
-    features = strchr(name, ',');
-    if (features) {
-        features[0] = 0;
-        features++;
-    }
-
-    oc = cpu_class_by_name(TYPE_S390_CPU, name);
-    if (!oc) {
-        error_setg(errp, "Unknown CPU definition \'%s\'", name);
-        g_free(name);
-        return NULL;
-    }
-    typename = object_class_get_name(oc);
-
-    if (!features_parsed) {
-        features_parsed = true;
-        cc = CPU_CLASS(oc);
-        cc->parse_features(typename, features, errp);
-    }
-    g_free(name);
-
-    if (*errp) {
-        return NULL;
-    }
-    return S390_CPU(CPU(object_new(typename)));
-}
-
-S390CPU *s390x_new_cpu(const char *cpu_model, uint32_t core_id, Error **errp)
-{
-    S390CPU *cpu;
+    S390CPU *cpu = S390_CPU(object_new(typename));
     Error *err = NULL;
 
-    cpu = cpu_s390x_create(cpu_model, &err);
-    if (err != NULL) {
-        goto out;
-    }
-
     object_property_set_int(OBJECT(cpu), core_id, "core-id", &err);
     if (err != NULL) {
         goto out;
target/s390x/internal.h +0 -1
index b4d3583b24..bc8f83129a 100644
@@ -337,7 +337,6 @@ uint64_t get_psw_mask(CPUS390XState *env);
 void s390_cpu_recompute_watchpoints(CPUState *cs);
 void s390x_tod_timer(void *opaque);
 void s390x_cpu_timer(void *opaque);
-S390CPU *cpu_s390x_create(const char *cpu_model, Error **errp);
 void do_restart_interrupt(CPUS390XState *env);
 #ifndef CONFIG_USER_ONLY
 LowCore *cpu_map_lowcore(CPUS390XState *env);
#35 lore raw

PATCH v4 20/21 s390x: generate sclp cpu information from possible_cpus

In reply to David Hildenbrand

This is the first step to allow hot plugging of CPUs in a non-sequential order. If a cpu is available ("plugged") can directly be decided by looking at the cpu state pointer.

This makes sure, that really only cpus attached to the machine are reported.

---
 hw/s390x/sclp.c | 34 ++++++++++++++--------------------
 1 file changed, 14 insertions(+), 20 deletions(-)
hw/s390x/sclp.c +14 -20
index fd097262c7..30aefbfd15 100644
@@ -34,16 +34,21 @@ static inline SCLPDevice *get_sclp_device(void)
     return sclp;
 }
 
-static void prepare_cpu_entries(SCLPDevice *sclp, CPUEntry *entry, int count)
+static void prepare_cpu_entries(SCLPDevice *sclp, CPUEntry *entry, int *count)
 {
+    MachineState *ms = MACHINE(qdev_get_machine());
     uint8_t features[SCCB_CPU_FEATURE_LEN] = { 0 };
     int i;
 
     s390_get_feat_block(S390_FEAT_TYPE_SCLP_CPU, features);
-    for (i = 0; i < count; i++) {
-        entry[i].address = i;
-        entry[i].type = 0;
-        memcpy(entry[i].features, features, sizeof(entry[i].features));
+    for (i = 0, *count = 0; i < ms->possible_cpus->len; i++) {
+        if (!ms->possible_cpus->cpus[i].cpu) {
+            continue;
+        }
+        entry[*count].address = ms->possible_cpus->cpus[i].arch_id;
+        entry[*count].type = 0;
+        memcpy(entry[*count].features, features, sizeof(features));
+        (*count)++;
     }
 }
 
@@ -53,17 +58,13 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
     ReadInfo *read_info = (ReadInfo *) sccb;
     MachineState *machine = MACHINE(qdev_get_machine());
     sclpMemoryHotplugDev *mhd = get_sclp_memory_hotplug_dev();
-    CPUState *cpu;
-    int cpu_count = 0;
+    int cpu_count;
     int rnsize, rnmax;
     int slots = MIN(machine->ram_slots, s390_get_memslot_count());
     IplParameterBlock *ipib = s390_ipl_get_iplb();
 
-    CPU_FOREACH(cpu) {
-        cpu_count++;
-    }
-
     /* CPU information */
+    prepare_cpu_entries(sclp, read_info->entries, &cpu_count);
     read_info->entries_cpu = cpu_to_be16(cpu_count);
     read_info->offset_cpu = cpu_to_be16(offsetof(ReadInfo, entries));
     read_info->highest_cpu = cpu_to_be16(max_cpus);
@@ -76,8 +77,6 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
     s390_get_feat_block(S390_FEAT_TYPE_SCLP_CONF_CHAR_EXT,
                          read_info->conf_char_ext);
 
-    prepare_cpu_entries(sclp, read_info->entries, cpu_count);
-
     read_info->facilities = cpu_to_be64(SCLP_HAS_CPU_INFO |
                                         SCLP_HAS_IOA_RECONFIG);
 
@@ -333,13 +332,9 @@ static void unassign_storage(SCLPDevice *sclp, SCCB *sccb)
 static void sclp_read_cpu_info(SCLPDevice *sclp, SCCB *sccb)
 {
     ReadCpuInfo *cpu_info = (ReadCpuInfo *) sccb;
-    CPUState *cpu;
-    int cpu_count = 0;
-
-    CPU_FOREACH(cpu) {
-        cpu_count++;
-    }
+    int cpu_count;
 
+    prepare_cpu_entries(sclp, cpu_info->entries, &cpu_count);
     cpu_info->nr_configured = cpu_to_be16(cpu_count);
     cpu_info->offset_configured = cpu_to_be16(offsetof(ReadCpuInfo, entries));
     cpu_info->nr_standby = cpu_to_be16(0);
@@ -348,7 +343,6 @@ static void sclp_read_cpu_info(SCLPDevice *sclp, SCCB *sccb)
     cpu_info->offset_standby = cpu_to_be16(cpu_info->offset_configured
         + cpu_info->nr_configured*sizeof(CPUEntry));
 
-    prepare_cpu_entries(sclp, cpu_info->entries, cpu_count);
 
     sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_READ_COMPLETION);
 }
Signature · 1 line
2.13.5
#36 lore raw

PATCH v4 21/21 s390x: allow CPU hotplug in random core-id order

In reply to David Hildenbrand

SCLP correctly indicates the core-id aka. CPU address for each available CPU.

As the core-id corresponds to cpu_index, also a newly created kvm vcpu gets assigned this core-id as vcpu id. So SIGP in the kernel works correctly (it uses the vcpu id to lookup the correct CPU).

So there should be nothing hindering us from hotplugging CPUs in random core-id order.

This now makes sure that the output from "query-hotpluggable-cpus" is completely true. Until now, a specific order is implicit. Performance vice, hotplugging CPUs in non-sequential order might not be the best thing to do, as VCPU lookup inside KVM might be a little slower. But that doesn't hinder us from supporting it.

next_core_id is now used by linux user only.

---
 target/s390x/cpu.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)
target/s390x/cpu.c +1 -7
index 7f174f90a4..b292be7ae3 100644
@@ -200,6 +200,7 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
 #else
     /* implicitly set for linux-user only */
     cpu->env.core_id = scc->next_core_id;
+    scc->next_core_id++;
 #endif
 
     if (cpu_exists(cpu->env.core_id)) {
@@ -207,12 +208,6 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
                    ", it already exists", cpu->env.core_id);
         goto out;
     }
-    if (cpu->env.core_id != scc->next_core_id) {
-        error_setg(&err, "Unable to add CPU with core-id: %" PRIu32
-                   ", the next available core-id is %" PRIu32, cpu->env.core_id,
-                   scc->next_core_id);
-        goto out;
-    }
 
     /* sync cs->cpu_index and env->core_id. The latter is needed for TCG. */
     cs->cpu_index = env->core_id;
@@ -220,7 +215,6 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
     if (err != NULL) {
         goto out;
     }
-    scc->next_core_id++;
 
 #if !defined(CONFIG_USER_ONLY)
     qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
Signature · 1 line
2.13.5
#37 lore raw
In reply to David Hildenbrand
Quoted 4 lines · On Mon, 11 Sep 2017 17:21:29 +0200 David Hildenbrand <[email protected]> wrote:

The first patches are a bunch of cleanups. I decided to go the extra mile and implement CPU hotplug via "device_add", as well as "query-hotpluggable-cpus".

Quoted 8 lines

On s390x, only complete cores can be plugged. CPU hot unplug is currently not supported by the architecture.

Support for hotplugging CPUs in random core-id order (last two patches) is added. We once hat a KVM bug preventing this, but the stable patch should now be included in relevant places - 152e9f65d66f ("KVM: s390: fix wrong lookup of VCPUs by array index"). Current tooling will plug them in sequential order anyway, so it should not hurt.

do you plan to convert hw/s390x/s390-virtio.c machine to possible_cpus as well? it's not necessary to enable hotplug on it but sharing code and initializing cpus the same way would be plus.

[...]

#38 lore raw
Quoted 16 lines · Igor Mammedov
Quoted 4 lines · On Mon, 11 Sep 2017 17:21:29 +0200 David Hildenbrand <[email protected]> wrote:

The first patches are a bunch of cleanups. I decided to go the extra mile and implement CPU hotplug via "device_add", as well as "query-hotpluggable-cpus".

Quoted 8 lines

On s390x, only complete cores can be plugged. CPU hot unplug is currently not supported by the architecture.

Support for hotplugging CPUs in random core-id order (last two patches) is added. We once hat a KVM bug preventing this, but the stable patch should now be included in relevant places - 152e9f65d66f ("KVM: s390: fix wrong lookup of VCPUs by array index"). Current tooling will plug them in sequential order anyway, so it should not hurt.

Quoted 3 lines

do you plan to convert hw/s390x/s390-virtio.c machine to possible_cpus as well? it's not necessary to enable hotplug on it but sharing code and initializing cpus the same way would be plus.

See patch #3. s390-virtio.c is an old leftover, the machine doesn't exist anymore. So this should be clean.

Signature · 3 lines
Thanks,

David