cpus: Remove CPUClass::has_work() handler

All handlers have been converted to SysemuCPUOps::has_work().
Remove CPUClass::has_work along with cpu_common_has_work() and
simplify cpu_has_work(), making SysemuCPUOps::has_work handler
mandatory.

Note, since cpu-common.c is in meson's common_ss[] source set, we
must define cpu_exec_class_post_init() in cpu-target.c (which is
in the specific_ss[] source set) to have CONFIG_USER_ONLY defined.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20250125170125.32855-25-philmd@linaro.org>

hw/core/cpu-common.c

@@ -134,11 +134,6 @@ static void cpu_common_reset_hold(Object *obj, ResetType type)
     cpu_exec_reset_hold(cpu);
 }
 
-static bool cpu_common_has_work(CPUState *cs)
-{
-    return false;
-}
-
 ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model)
 {
     ObjectClass *oc;
@@ -259,6 +254,8 @@ static void cpu_common_initfn(Object *obj)
 {
     CPUState *cpu = CPU(obj);
 
+    cpu_exec_class_post_init(CPU_GET_CLASS(obj));
+
     /* cache the cpu class for the hotpath */
     cpu->cc = CPU_GET_CLASS(cpu);
 
@@ -331,7 +328,6 @@ static void cpu_common_class_init(ObjectClass *klass, void *data)
 
     k->parse_features = cpu_common_parse_features;
     k->get_arch_id = cpu_common_get_arch_id;
-    k->has_work = cpu_common_has_work;
     k->gdb_read_register = cpu_common_gdb_read_register;
     k->gdb_write_register = cpu_common_gdb_write_register;
     set_bit(DEVICE_CATEGORY_CPU, dc->categories);

hw/core/cpu-system.c

@@ -33,14 +33,9 @@
 
 bool cpu_has_work(CPUState *cpu)
 {
-    if (cpu->cc->sysemu_ops->has_work) {
     return cpu->cc->sysemu_ops->has_work(cpu);
 }
 
-    g_assert(cpu->cc->has_work);
-    return cpu->cc->has_work(cpu);
-}
-
 bool cpu_paging_enabled(const CPUState *cpu)
 {
     if (cpu->cc->sysemu_ops->get_paging_enabled) {
@@ -188,6 +183,12 @@ void cpu_class_init_props(DeviceClass *dc)
     device_class_set_props(dc, cpu_system_props);
 }
 
+void cpu_exec_class_post_init(CPUClass *cc)
+{
+    /* Check mandatory SysemuCPUOps handlers */
+    g_assert(cc->sysemu_ops->has_work);
+}
+
 void cpu_exec_initfn(CPUState *cpu)
 {
     cpu->memory = get_system_memory();

hw/core/cpu-user.c

@@ -27,6 +27,11 @@ void cpu_class_init_props(DeviceClass *dc)
     device_class_set_props(dc, cpu_user_props);
 }
 
+void cpu_exec_class_post_init(CPUClass *cc)
+{
+    /* nothing to do */
+}
+
 void cpu_exec_initfn(CPUState *cpu)
 {
     /* nothing to do */

include/hw/core/cpu.h

@@ -104,7 +104,6 @@ struct SysemuCPUOps;
  *                 instantiatable CPU type.
  * @parse_features: Callback to parse command line arguments.
  * @reset_dump_flags: #CPUDumpFlags to use for reset logging.
- * @has_work: Callback for checking if there is work to do.
  * @mmu_index: Callback for choosing softmmu mmu index;
  *       may be used internally by memory_rw_debug without TCG.
  * @memory_rw_debug: Callback for GDB memory access.
@@ -153,7 +152,6 @@ struct CPUClass {
     ObjectClass *(*class_by_name)(const char *cpu_model);
     void (*parse_features)(const char *typename, char *str, Error **errp);
 
-    bool (*has_work)(CPUState *cpu);
     int (*mmu_index)(CPUState *cpu, bool ifetch);
     int (*memory_rw_debug)(CPUState *cpu, vaddr addr,
                            uint8_t *buf, int len, bool is_write);
@@ -1156,6 +1154,7 @@ G_NORETURN void cpu_abort(CPUState *cpu, const char *fmt, ...)
 
 /* $(top_srcdir)/cpu.c */
 void cpu_class_init_props(DeviceClass *dc);
+void cpu_exec_class_post_init(CPUClass *cc);
 void cpu_exec_initfn(CPUState *cpu);
 void cpu_vmstate_register(CPUState *cpu);
 void cpu_vmstate_unregister(CPUState *cpu);

include/hw/core/sysemu-cpu-ops.h

@@ -19,7 +19,7 @@ typedef struct SysemuCPUOps {
     /**
      * @has_work: Callback for checking if there is work to do.
      */
-    bool (*has_work)(CPUState *cpu);
+    bool (*has_work)(CPUState *cpu); /* MANDATORY NON-NULL */
     /**
      * @get_memory_mapping: Callback for obtaining the memory mappings.
      */