spapr/xive: Allocate IPIs independently from the other sources

The vCPU IPIs are now allocated in kvmppc_xive_cpu_connect() when the
vCPU connects to the KVM device and not when all the sources are reset
in kvmppc_xive_source_reset()

This requires extra care for hotplug vCPUs and VM restore.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200820134547.2355743-4-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Cédric Le Goater 2020-08-20 15:45:46 +02:00 committed by David Gibson
parent fa94447a2c
commit acbdb9956f

View File

@ -146,6 +146,15 @@ int kvmppc_xive_cpu_synchronize_state(XiveTCTX *tctx, Error **errp)
return s.ret;
}
static int kvmppc_xive_reset_ipi(SpaprXive *xive, CPUState *cs, Error **errp)
{
unsigned long ipi = kvm_arch_vcpu_id(cs);
uint64_t state = 0;
return kvm_device_access(xive->fd, KVM_DEV_XIVE_GRP_SOURCE, ipi,
&state, true, errp);
}
int kvmppc_xive_cpu_connect(XiveTCTX *tctx, Error **errp)
{
ERRP_GUARD();
@ -175,6 +184,12 @@ int kvmppc_xive_cpu_connect(XiveTCTX *tctx, Error **errp)
return ret;
}
/* Create/reset the vCPU IPI */
ret = kvmppc_xive_reset_ipi(xive, tctx->cs, errp);
if (ret < 0) {
return ret;
}
kvm_cpu_enable(tctx->cs);
return 0;
}
@ -234,6 +249,12 @@ int kvmppc_xive_source_reset_one(XiveSource *xsrc, int srcno, Error **errp)
assert(xive->fd != -1);
/*
* The vCPU IPIs are now allocated in kvmppc_xive_cpu_connect()
* and not with all sources in kvmppc_xive_source_reset()
*/
assert(srcno >= SPAPR_XIRQ_BASE);
if (xive_source_irq_is_lsi(xsrc, srcno)) {
state |= KVM_XIVE_LEVEL_SENSITIVE;
if (xsrc->status[srcno] & XIVE_STATUS_ASSERTED) {
@ -245,12 +266,28 @@ int kvmppc_xive_source_reset_one(XiveSource *xsrc, int srcno, Error **errp)
true, errp);
}
/*
* To be valid, a source must have been claimed by the machine (valid
* entry in the EAS table) and if it is a vCPU IPI, the vCPU should
* have been enabled, which means the IPI has been allocated in
* kvmppc_xive_cpu_connect().
*/
static bool xive_source_is_valid(SpaprXive *xive, int i)
{
return xive_eas_is_valid(&xive->eat[i]) &&
(i >= SPAPR_XIRQ_BASE || kvm_cpu_is_enabled(i));
}
static int kvmppc_xive_source_reset(XiveSource *xsrc, Error **errp)
{
SpaprXive *xive = SPAPR_XIVE(xsrc->xive);
int i;
for (i = 0; i < xsrc->nr_irqs; i++) {
/*
* Skip the vCPU IPIs. These are created/reset when the vCPUs are
* connected in kvmppc_xive_cpu_connect()
*/
for (i = SPAPR_XIRQ_BASE; i < xsrc->nr_irqs; i++) {
int ret;
if (!xive_eas_is_valid(&xive->eat[i])) {
@ -332,7 +369,7 @@ static void kvmppc_xive_source_get_state(XiveSource *xsrc)
for (i = 0; i < xsrc->nr_irqs; i++) {
uint8_t pq;
if (!xive_eas_is_valid(&xive->eat[i])) {
if (!xive_source_is_valid(xive, i)) {
continue;
}
@ -515,7 +552,7 @@ static void kvmppc_xive_change_state_handler(void *opaque, int running,
uint8_t pq;
uint8_t old_pq;
if (!xive_eas_is_valid(&xive->eat[i])) {
if (!xive_source_is_valid(xive, i)) {
continue;
}
@ -543,7 +580,7 @@ static void kvmppc_xive_change_state_handler(void *opaque, int running,
for (i = 0; i < xsrc->nr_irqs; i++) {
uint8_t pq;
if (!xive_eas_is_valid(&xive->eat[i])) {
if (!xive_source_is_valid(xive, i)) {
continue;
}
@ -658,7 +695,7 @@ int kvmppc_xive_post_load(SpaprXive *xive, int version_id)
/* Restore the EAT */
for (i = 0; i < xive->nr_irqs; i++) {
if (!xive_eas_is_valid(&xive->eat[i])) {
if (!xive_source_is_valid(xive, i)) {
continue;
}