@@ -20,6 +20,7 @@
#include <asm/xics.h>
#include <asm/debug.h>
#include <asm/time.h>
+#include <asm/spinlock.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
@@ -39,7 +40,7 @@
* LOCKING
* =======
*
- * Each ICS has a mutex protecting the information about the IRQ
+ * Each ICS has a spin lock protecting the information about the IRQ
* sources and avoiding simultaneous deliveries if the same interrupt.
*
* ICP operations are done via a single compare & swap transaction
@@ -109,7 +110,10 @@ static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
{
int i;
- mutex_lock(&ics->lock);
+ unsigned long flags;
+
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
struct ics_irq_state *state = &ics->irq_state[i];
@@ -120,12 +124,15 @@ static void ics_check_resend(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
XICS_DBG("resend %#x prio %#x\n", state->number,
state->priority);
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
icp_deliver_irq(xics, icp, state->number);
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
}
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
}
static bool write_xive(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
@@ -133,8 +140,10 @@ static bool write_xive(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
u32 server, u32 priority, u32 saved_priority)
{
bool deliver;
+ unsigned long flags;
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
state->server = server;
state->priority = priority;
@@ -145,7 +154,8 @@ static bool write_xive(struct kvmppc_xics *xics, struct kvmppc_ics *ics,
deliver = true;
}
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
return deliver;
}
@@ -186,6 +196,7 @@ int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority)
struct kvmppc_ics *ics;
struct ics_irq_state *state;
u16 src;
+ unsigned long flags;
if (!xics)
return -ENODEV;
@@ -195,10 +206,12 @@ int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority)
return -EINVAL;
state = &ics->irq_state[src];
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
*server = state->server;
*priority = state->priority;
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
return 0;
}
@@ -365,6 +378,7 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
struct kvmppc_ics *ics;
u32 reject;
u16 src;
+ unsigned long flags;
/*
* This is used both for initial delivery of an interrupt and
@@ -391,7 +405,8 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
state = &ics->irq_state[src];
/* Get a lock on the ICS */
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
/* Get our server */
if (!icp || state->server != icp->server_num) {
@@ -434,7 +449,7 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
*
* Note that if successful, the new delivery might have itself
* rejected an interrupt that was "delivered" before we took the
- * icp mutex.
+ * ics spin lock.
*
* In this case we do the whole sequence all over again for the
* new guy. We cannot assume that the rejected interrupt is less
@@ -448,7 +463,8 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
* Delivery was successful, did we reject somebody else ?
*/
if (reject && reject != XICS_IPI) {
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
new_irq = reject;
goto again;
}
@@ -468,12 +484,14 @@ static void icp_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
*/
smp_mb();
if (!icp->state.need_resend) {
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
goto again;
}
}
out:
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
}
static void icp_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
@@ -880,6 +898,7 @@ static int xics_debug_show(struct seq_file *m, void *private)
struct kvm *kvm = xics->kvm;
struct kvm_vcpu *vcpu;
int icsid, i;
+ unsigned long flags;
unsigned long t_rm_kick_vcpu, t_rm_check_resend;
unsigned long t_rm_reject, t_rm_notify_eoi;
@@ -924,7 +943,8 @@ static int xics_debug_show(struct seq_file *m, void *private)
seq_printf(m, "=========\nICS state for ICS 0x%x\n=========\n",
icsid);
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
struct ics_irq_state *irq = &ics->irq_state[i];
@@ -935,7 +955,8 @@ static int xics_debug_show(struct seq_file *m, void *private)
irq->resend, irq->masked_pending);
}
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
}
return 0;
}
@@ -988,7 +1009,6 @@ static struct kvmppc_ics *kvmppc_xics_create_ics(struct kvm *kvm,
if (!ics)
goto out;
- mutex_init(&ics->lock);
ics->icsid = icsid;
for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
@@ -1130,13 +1150,15 @@ static int xics_get_source(struct kvmppc_xics *xics, long irq, u64 addr)
u64 __user *ubufp = (u64 __user *) addr;
u16 idx;
u64 val, prio;
+ unsigned long flags;
ics = kvmppc_xics_find_ics(xics, irq, &idx);
if (!ics)
return -ENOENT;
irqp = &ics->irq_state[idx];
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
ret = -ENOENT;
if (irqp->exists) {
val = irqp->server;
@@ -1152,7 +1174,8 @@ static int xics_get_source(struct kvmppc_xics *xics, long irq, u64 addr)
val |= KVM_XICS_PENDING;
ret = 0;
}
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
if (!ret && put_user(val, ubufp))
ret = -EFAULT;
@@ -1169,6 +1192,7 @@ static int xics_set_source(struct kvmppc_xics *xics, long irq, u64 addr)
u64 val;
u8 prio;
u32 server;
+ unsigned long flags;
if (irq < KVMPPC_XICS_FIRST_IRQ || irq >= KVMPPC_XICS_NR_IRQS)
return -ENOENT;
@@ -1189,7 +1213,8 @@ static int xics_set_source(struct kvmppc_xics *xics, long irq, u64 addr)
kvmppc_xics_find_server(xics->kvm, server) == NULL)
return -EINVAL;
- mutex_lock(&ics->lock);
+ local_irq_save(flags);
+ arch_spin_lock(&ics->lock);
irqp->server = server;
irqp->saved_priority = prio;
if (val & KVM_XICS_MASKED)
@@ -1201,7 +1226,8 @@ static int xics_set_source(struct kvmppc_xics *xics, long irq, u64 addr)
if ((val & KVM_XICS_PENDING) && (val & KVM_XICS_LEVEL_SENSITIVE))
irqp->asserted = 1;
irqp->exists = 1;
- mutex_unlock(&ics->lock);
+ arch_spin_unlock(&ics->lock);
+ local_irq_restore(flags);
if (val & KVM_XICS_PENDING)
icp_deliver_irq(xics, NULL, irqp->number);
@@ -90,7 +90,7 @@ struct kvmppc_icp {
};
struct kvmppc_ics {
- struct mutex lock;
+ arch_spinlock_t lock;
u16 icsid;
struct ics_irq_state irq_state[KVMPPC_XICS_IRQ_PER_ICS];
};