cryptodev: support QoS

Add 'throttle-bps' and 'throttle-ops' limitation to set QoS. The
two arguments work with both QEMU command line and QMP command.

Example of QEMU command line:
-object cryptodev-backend-builtin,id=cryptodev1,throttle-bps=1600,\
throttle-ops=100

Example of QMP command:
virsh qemu-monitor-command buster --hmp qom-set /objects/cryptodev1 \
throttle-ops 100

or cancel limitation:
virsh qemu-monitor-command buster --hmp qom-set /objects/cryptodev1 \
throttle-ops 0

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Message-Id: <20230301105847.253084-11-pizhenwei@bytedance.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

backends/cryptodev.c

@@ -28,6 +28,7 @@
 #include "qapi/visitor.h"
 #include "qemu/config-file.h"
 #include "qemu/error-report.h"
+#include "qemu/main-loop.h"
 #include "qom/object_interfaces.h"
 #include "hw/virtio/virtio-crypto.h"
 
@@ -203,17 +204,53 @@ static int cryptodev_backend_account(CryptoDevBackend *backend,
     return len;
 }
 
+static void cryptodev_backend_throttle_timer_cb(void *opaque)
+{
+    CryptoDevBackend *backend = (CryptoDevBackend *)opaque;
+    CryptoDevBackendOpInfo *op_info, *tmpop;
+    int ret;
+
+    QTAILQ_FOREACH_SAFE(op_info, &backend->opinfos, next, tmpop) {
+        QTAILQ_REMOVE(&backend->opinfos, op_info, next);
+        ret = cryptodev_backend_account(backend, op_info);
+        if (ret < 0) {
+            op_info->cb(op_info->opaque, ret);
+            continue;
+        }
+
+        throttle_account(&backend->ts, true, ret);
+        cryptodev_backend_operation(backend, op_info);
+        if (throttle_enabled(&backend->tc) &&
+            throttle_schedule_timer(&backend->ts, &backend->tt, true)) {
+            break;
+        }
+    }
+}
+
 int cryptodev_backend_crypto_operation(
                  CryptoDevBackend *backend,
                  CryptoDevBackendOpInfo *op_info)
 {
     int ret;
 
+    if (!throttle_enabled(&backend->tc)) {
+        goto do_account;
+    }
+
+    if (throttle_schedule_timer(&backend->ts, &backend->tt, true) ||
+        !QTAILQ_EMPTY(&backend->opinfos)) {
+        QTAILQ_INSERT_TAIL(&backend->opinfos, op_info, next);
+        return 0;
+    }
+
+do_account:
     ret = cryptodev_backend_account(backend, op_info);
     if (ret < 0) {
         return ret;
     }
 
+    throttle_account(&backend->ts, true, ret);
+
     return cryptodev_backend_operation(backend, op_info);
 }
 
@@ -245,12 +282,98 @@ cryptodev_backend_set_queues(Object *obj, Visitor *v, const char *name,
     backend->conf.peers.queues = value;
 }
 
+static void cryptodev_backend_set_throttle(CryptoDevBackend *backend, int field,
+                                           uint64_t value, Error **errp)
+{
+    uint64_t orig = backend->tc.buckets[field].avg;
+    bool enabled = throttle_enabled(&backend->tc);
+
+    if (orig == value) {
+        return;
+    }
+
+    backend->tc.buckets[field].avg = value;
+    if (!throttle_enabled(&backend->tc)) {
+        throttle_timers_destroy(&backend->tt);
+        cryptodev_backend_throttle_timer_cb(backend); /* drain opinfos */
+        return;
+    }
+
+    if (!throttle_is_valid(&backend->tc, errp)) {
+        backend->tc.buckets[field].avg = orig; /* revert change */
+        return;
+    }
+
+    if (!enabled) {
+        throttle_init(&backend->ts);
+        throttle_timers_init(&backend->tt, qemu_get_aio_context(),
+                             QEMU_CLOCK_REALTIME,
+                             cryptodev_backend_throttle_timer_cb, /* FIXME */
+                             cryptodev_backend_throttle_timer_cb, backend);
+    }
+
+    throttle_config(&backend->ts, QEMU_CLOCK_REALTIME, &backend->tc);
+}
+
+static void cryptodev_backend_get_bps(Object *obj, Visitor *v,
+                                      const char *name, void *opaque,
+                                      Error **errp)
+{
+    CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
+    uint64_t value = backend->tc.buckets[THROTTLE_BPS_TOTAL].avg;
+
+    visit_type_uint64(v, name, &value, errp);
+}
+
+static void cryptodev_backend_set_bps(Object *obj, Visitor *v, const char *name,
+                                      void *opaque, Error **errp)
+{
+    CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
+    uint64_t value;
+
+    if (!visit_type_uint64(v, name, &value, errp)) {
+        return;
+    }
+
+    cryptodev_backend_set_throttle(backend, THROTTLE_BPS_TOTAL, value, errp);
+}
+
+static void cryptodev_backend_get_ops(Object *obj, Visitor *v, const char *name,
+                                      void *opaque, Error **errp)
+{
+    CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
+    uint64_t value = backend->tc.buckets[THROTTLE_OPS_TOTAL].avg;
+
+    visit_type_uint64(v, name, &value, errp);
+}
+
+static void cryptodev_backend_set_ops(Object *obj, Visitor *v,
+                                       const char *name, void *opaque,
+                                       Error **errp)
+{
+    CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
+    uint64_t value;
+
+    if (!visit_type_uint64(v, name, &value, errp)) {
+        return;
+    }
+
+    cryptodev_backend_set_throttle(backend, THROTTLE_OPS_TOTAL, value, errp);
+}
+
 static void
 cryptodev_backend_complete(UserCreatable *uc, Error **errp)
 {
     CryptoDevBackend *backend = CRYPTODEV_BACKEND(uc);
     CryptoDevBackendClass *bc = CRYPTODEV_BACKEND_GET_CLASS(uc);
     uint32_t services;
+    uint64_t value;
+
+    QTAILQ_INIT(&backend->opinfos);
+    value = backend->tc.buckets[THROTTLE_OPS_TOTAL].avg;
+    cryptodev_backend_set_throttle(backend, THROTTLE_OPS_TOTAL, value, errp);
+    value = backend->tc.buckets[THROTTLE_BPS_TOTAL].avg;
+    cryptodev_backend_set_throttle(backend, THROTTLE_BPS_TOTAL, value, errp);
 
     if (bc->init) {
         bc->init(backend, errp);
@@ -294,8 +417,12 @@ cryptodev_backend_can_be_deleted(UserCreatable *uc)
 
 static void cryptodev_backend_instance_init(Object *obj)
 {
+    CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
+
     /* Initialize devices' queues property to 1 */
     object_property_set_int(obj, "queues", 1, NULL);
+
+    throttle_config_init(&backend->tc);
 }
 
 static void cryptodev_backend_finalize(Object *obj)
@@ -303,6 +430,9 @@ static void cryptodev_backend_finalize(Object *obj)
     CryptoDevBackend *backend = CRYPTODEV_BACKEND(obj);
 
     cryptodev_backend_cleanup(backend, NULL);
+    if (throttle_enabled(&backend->tc)) {
+        throttle_timers_destroy(&backend->tt);
+    }
 }
 
 static void
@@ -318,6 +448,14 @@ cryptodev_backend_class_init(ObjectClass *oc, void *data)
                               cryptodev_backend_get_queues,
                               cryptodev_backend_set_queues,
                               NULL, NULL);
+    object_class_property_add(oc, "throttle-bps", "uint64",
+                              cryptodev_backend_get_bps,
+                              cryptodev_backend_set_bps,
+                              NULL, NULL);
+    object_class_property_add(oc, "throttle-ops", "uint64",
+                              cryptodev_backend_get_ops,
+                              cryptodev_backend_set_ops,
+                              NULL, NULL);
 }
 
 static const TypeInfo cryptodev_backend_info = {

include/sysemu/cryptodev.h

@@ -24,6 +24,7 @@
 #define CRYPTODEV_H
 
 #include "qemu/queue.h"
+#include "qemu/throttle.h"
 #include "qom/object.h"
 #include "qapi/qapi-types-cryptodev.h"
 
@@ -187,6 +188,7 @@ typedef struct CryptoDevBackendOpInfo {
         CryptoDevBackendSymOpInfo *sym_op_info;
         CryptoDevBackendAsymOpInfo *asym_op_info;
     } u;
+    QTAILQ_ENTRY(CryptoDevBackendOpInfo) next;
 } CryptoDevBackendOpInfo;
 
 struct CryptoDevBackendClass {
@@ -273,6 +275,11 @@ struct CryptoDevBackend {
     CryptoDevBackendConf conf;
     CryptodevBackendSymStat *sym_stat;
     CryptodevBackendAsymStat *asym_stat;
+
+    ThrottleState ts;
+    ThrottleTimers tt;
+    ThrottleConfig tc;
+    QTAILQ_HEAD(, CryptoDevBackendOpInfo) opinfos;
 };
 
 #define CryptodevSymStatInc(be, op, bytes) do { \

qapi/qom.json

@@ -278,10 +278,16 @@
 #          cryptodev-backend and must be 1 for cryptodev-backend-builtin.
 #          (default: 1)
 #
+# @throttle-bps: limit total bytes per second (Since 8.0)
+#
+# @throttle-ops: limit total operations per second (Since 8.0)
+#
 # Since: 2.8
 ##
 { 'struct': 'CryptodevBackendProperties',
-  'data': { '*queues': 'uint32' } }
+  'data': { '*queues': 'uint32',
+            '*throttle-bps': 'uint64',
+            '*throttle-ops': 'uint64' } }
 
 ##
 # @CryptodevVhostUserProperties: