1 /*
2 * QEMU event-loop base
3 *
4 * Copyright (C) 2022 Red Hat Inc
5 *
6 * Authors:
7 * Stefan Hajnoczi <stefanha@redhat.com>
8 * Nicolas Saenz Julienne <nsaenzju@redhat.com>
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2 or later.
11 * See the COPYING file in the top-level directory.
12 */
13
14 #include "qemu/osdep.h"
15 #include "qom/object_interfaces.h"
16 #include "qapi/error.h"
17 #include "block/thread-pool.h"
18 #include "system/event-loop-base.h"
19
20 typedef struct {
21 const char *name;
22 ptrdiff_t offset; /* field's byte offset in EventLoopBase struct */
23 } EventLoopBaseParamInfo;
24
event_loop_base_instance_init(Object * obj)25 static void event_loop_base_instance_init(Object *obj)
26 {
27 EventLoopBase *base = EVENT_LOOP_BASE(obj);
28
29 base->thread_pool_max = THREAD_POOL_MAX_THREADS_DEFAULT;
30 }
31
32 static EventLoopBaseParamInfo aio_max_batch_info = {
33 "aio-max-batch", offsetof(EventLoopBase, aio_max_batch),
34 };
35 static EventLoopBaseParamInfo thread_pool_min_info = {
36 "thread-pool-min", offsetof(EventLoopBase, thread_pool_min),
37 };
38 static EventLoopBaseParamInfo thread_pool_max_info = {
39 "thread-pool-max", offsetof(EventLoopBase, thread_pool_max),
40 };
41
event_loop_base_get_param(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)42 static void event_loop_base_get_param(Object *obj, Visitor *v,
43 const char *name, void *opaque, Error **errp)
44 {
45 EventLoopBase *event_loop_base = EVENT_LOOP_BASE(obj);
46 EventLoopBaseParamInfo *info = opaque;
47 int64_t *field = (void *)event_loop_base + info->offset;
48
49 visit_type_int64(v, name, field, errp);
50 }
51
event_loop_base_set_param(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)52 static void event_loop_base_set_param(Object *obj, Visitor *v,
53 const char *name, void *opaque, Error **errp)
54 {
55 EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(obj);
56 EventLoopBase *base = EVENT_LOOP_BASE(obj);
57 EventLoopBaseParamInfo *info = opaque;
58 int64_t *field = (void *)base + info->offset;
59 int64_t value;
60
61 if (!visit_type_int64(v, name, &value, errp)) {
62 return;
63 }
64
65 if (value < 0) {
66 error_setg(errp, "%s value must be in range [0, %" PRId64 "]",
67 info->name, INT64_MAX);
68 return;
69 }
70
71 *field = value;
72
73 if (bc->update_params) {
74 bc->update_params(base, errp);
75 }
76 }
77
event_loop_base_complete(UserCreatable * uc,Error ** errp)78 static void event_loop_base_complete(UserCreatable *uc, Error **errp)
79 {
80 EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(uc);
81 EventLoopBase *base = EVENT_LOOP_BASE(uc);
82
83 if (bc->init) {
84 bc->init(base, errp);
85 }
86 }
87
event_loop_base_can_be_deleted(UserCreatable * uc)88 static bool event_loop_base_can_be_deleted(UserCreatable *uc)
89 {
90 EventLoopBaseClass *bc = EVENT_LOOP_BASE_GET_CLASS(uc);
91 EventLoopBase *backend = EVENT_LOOP_BASE(uc);
92
93 if (bc->can_be_deleted) {
94 return bc->can_be_deleted(backend);
95 }
96
97 return true;
98 }
99
event_loop_base_class_init(ObjectClass * klass,const void * class_data)100 static void event_loop_base_class_init(ObjectClass *klass,
101 const void *class_data)
102 {
103 UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
104 ucc->complete = event_loop_base_complete;
105 ucc->can_be_deleted = event_loop_base_can_be_deleted;
106
107 object_class_property_add(klass, "aio-max-batch", "int",
108 event_loop_base_get_param,
109 event_loop_base_set_param,
110 NULL, &aio_max_batch_info);
111 object_class_property_add(klass, "thread-pool-min", "int",
112 event_loop_base_get_param,
113 event_loop_base_set_param,
114 NULL, &thread_pool_min_info);
115 object_class_property_add(klass, "thread-pool-max", "int",
116 event_loop_base_get_param,
117 event_loop_base_set_param,
118 NULL, &thread_pool_max_info);
119 }
120
121 static const TypeInfo event_loop_base_info = {
122 .name = TYPE_EVENT_LOOP_BASE,
123 .parent = TYPE_OBJECT,
124 .instance_size = sizeof(EventLoopBase),
125 .instance_init = event_loop_base_instance_init,
126 .class_size = sizeof(EventLoopBaseClass),
127 .class_init = event_loop_base_class_init,
128 .abstract = true,
129 .interfaces = (const InterfaceInfo[]) {
130 { TYPE_USER_CREATABLE },
131 { }
132 }
133 };
134
register_types(void)135 static void register_types(void)
136 {
137 type_register_static(&event_loop_base_info);
138 }
139 type_init(register_types);
140