qdev: Introduce lost tick policy property

Potentially tick-generating timer devices will gain a common property:
lock_tick_policy. It allows to encode 4 different ways how to deal with
tick events the guest did not process in time:

discard - ignore lost ticks (e.g. if the guest compensates for them
          already)
delay   - replay all lost ticks in a row once the guest accepts them
          again
merge   - if multiple ticks are lost, all of them are merged into one
          which is replayed once the guest accepts it again
slew    - lost ticks are gradually replayed at a higher frequency than
          the original tick

Not all timer device will need to support all modes. However, all need
to accept the configuration via this common property.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Jan Kiszka 2012-01-23 20:15:11 +01:00 committed by Anthony Liguori
parent 67ed96f9f2
commit 4e4fa398db
3 changed files with 69 additions and 0 deletions

View file

@ -885,6 +885,55 @@ PropertyInfo qdev_prop_macaddr = {
.set = set_generic,
};
/* --- lost tick policy --- */
static const struct {
const char *name;
LostTickPolicy code;
} lost_tick_policy_table[] = {
{ .name = "discard", .code = LOST_TICK_DISCARD },
{ .name = "delay", .code = LOST_TICK_DELAY },
{ .name = "merge", .code = LOST_TICK_MERGE },
{ .name = "slew", .code = LOST_TICK_SLEW },
};
static int parse_lost_tick_policy(DeviceState *dev, Property *prop,
const char *str)
{
LostTickPolicy *ptr = qdev_get_prop_ptr(dev, prop);
int i;
for (i = 0; i < ARRAY_SIZE(lost_tick_policy_table); i++) {
if (!strcasecmp(str, lost_tick_policy_table[i].name)) {
*ptr = lost_tick_policy_table[i].code;
break;
}
}
if (i == ARRAY_SIZE(lost_tick_policy_table)) {
return -EINVAL;
}
return 0;
}
static int print_lost_tick_policy(DeviceState *dev, Property *prop, char *dest,
size_t len)
{
LostTickPolicy *ptr = qdev_get_prop_ptr(dev, prop);
return snprintf(dest, len, "%s", lost_tick_policy_table[*ptr].name);
}
PropertyInfo qdev_prop_losttickpolicy = {
.name = "lost_tick_policy",
.type = PROP_TYPE_LOSTTICKPOLICY,
.size = sizeof(LostTickPolicy),
.parse = parse_lost_tick_policy,
.print = print_lost_tick_policy,
.get = get_generic,
.set = set_generic,
};
/* --- pci address --- */
/*
@ -1127,6 +1176,12 @@ void qdev_prop_set_macaddr(DeviceState *dev, const char *name, uint8_t *value)
qdev_prop_set(dev, name, value, PROP_TYPE_MACADDR);
}
void qdev_prop_set_losttickpolicy(DeviceState *dev, const char *name,
LostTickPolicy *value)
{
qdev_prop_set(dev, name, value, PROP_TYPE_LOSTTICKPOLICY);
}
void qdev_prop_set_ptr(DeviceState *dev, const char *name, void *value)
{
qdev_prop_set(dev, name, &value, PROP_TYPE_PTR);

View file

@ -158,6 +158,7 @@ enum PropertyType {
PROP_TYPE_UINT64,
PROP_TYPE_TADDR,
PROP_TYPE_MACADDR,
PROP_TYPE_LOSTTICKPOLICY,
PROP_TYPE_DRIVE,
PROP_TYPE_CHR,
PROP_TYPE_STRING,
@ -307,6 +308,7 @@ extern PropertyInfo qdev_prop_string;
extern PropertyInfo qdev_prop_chr;
extern PropertyInfo qdev_prop_ptr;
extern PropertyInfo qdev_prop_macaddr;
extern PropertyInfo qdev_prop_losttickpolicy;
extern PropertyInfo qdev_prop_drive;
extern PropertyInfo qdev_prop_netdev;
extern PropertyInfo qdev_prop_vlan;
@ -367,6 +369,9 @@ extern PropertyInfo qdev_prop_pci_devfn;
DEFINE_PROP(_n, _s, _f, qdev_prop_drive, BlockDriverState *)
#define DEFINE_PROP_MACADDR(_n, _s, _f) \
DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
#define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_losttickpolicy, \
LostTickPolicy)
#define DEFINE_PROP_END_OF_LIST() \
{}
@ -389,6 +394,8 @@ void qdev_prop_set_vlan(DeviceState *dev, const char *name, VLANState *value);
int qdev_prop_set_drive(DeviceState *dev, const char *name, BlockDriverState *value) QEMU_WARN_UNUSED_RESULT;
void qdev_prop_set_drive_nofail(DeviceState *dev, const char *name, BlockDriverState *value);
void qdev_prop_set_macaddr(DeviceState *dev, const char *name, uint8_t *value);
void qdev_prop_set_losttickpolicy(DeviceState *dev, const char *name,
LostTickPolicy *value);
/* FIXME: Remove opaque pointer properties. */
void qdev_prop_set_ptr(DeviceState *dev, const char *name, void *value);
void qdev_prop_set_defaults(DeviceState *dev, Property *props);

View file

@ -250,6 +250,13 @@ typedef struct QEMUSGList QEMUSGList;
typedef uint64_t pcibus_t;
typedef enum LostTickPolicy {
LOST_TICK_DISCARD,
LOST_TICK_DELAY,
LOST_TICK_MERGE,
LOST_TICK_SLEW,
} LostTickPolicy;
void tcg_exec_init(unsigned long tb_size);
bool tcg_enabled(void);