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-rw-r--r--xen/common/event_channel.c82
-rw-r--r--xen/include/xen/event.h38
-rw-r--r--xen/include/xen/sched.h21
3 files changed, 112 insertions, 29 deletions
diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index 539a1980f5..87bca94087 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -121,11 +121,47 @@ static int virq_is_global(uint32_t virq)
}
+static struct evtchn *alloc_evtchn_bucket(struct domain *d, unsigned int port)
+{
+ struct evtchn *chn;
+ unsigned int i;
+
+ chn = xzalloc_array(struct evtchn, EVTCHNS_PER_BUCKET);
+ if ( !chn )
+ return NULL;
+
+ for ( i = 0; i < EVTCHNS_PER_BUCKET; i++ )
+ {
+ if ( xsm_alloc_security_evtchn(&chn[i]) )
+ {
+ while ( i-- )
+ xsm_free_security_evtchn(&chn[i]);
+ xfree(chn);
+ return NULL;
+ }
+ chn[i].port = port + i;
+ }
+ return chn;
+}
+
+static void free_evtchn_bucket(struct domain *d, struct evtchn *bucket)
+{
+ unsigned int i;
+
+ if ( !bucket )
+ return;
+
+ for ( i = 0; i < EVTCHNS_PER_BUCKET; i++ )
+ xsm_free_security_evtchn(bucket + i);
+
+ xfree(bucket);
+}
+
static int get_free_port(struct domain *d)
{
struct evtchn *chn;
+ struct evtchn **grp;
int port;
- int i, j;
if ( d->is_dying )
return -EINVAL;
@@ -137,22 +173,17 @@ static int get_free_port(struct domain *d)
if ( port == d->max_evtchns )
return -ENOSPC;
- chn = xzalloc_array(struct evtchn, EVTCHNS_PER_BUCKET);
- if ( unlikely(chn == NULL) )
- return -ENOMEM;
-
- for ( i = 0; i < EVTCHNS_PER_BUCKET; i++ )
+ if ( !group_from_port(d, port) )
{
- if ( xsm_alloc_security_evtchn(&chn[i]) )
- {
- for ( j = 0; j < i; j++ )
- xsm_free_security_evtchn(&chn[j]);
- xfree(chn);
+ grp = xzalloc_array(struct evtchn *, BUCKETS_PER_GROUP);
+ if ( !grp )
return -ENOMEM;
- }
- chn[i].port = port + i;
+ group_from_port(d, port) = grp;
}
+ chn = alloc_evtchn_bucket(d, port);
+ if ( !chn )
+ return -ENOMEM;
bucket_from_port(d, port) = chn;
return port;
@@ -1152,15 +1183,25 @@ int evtchn_init(struct domain *d)
{
evtchn_2l_init(d);
+ d->evtchn = alloc_evtchn_bucket(d, 0);
+ if ( !d->evtchn )
+ return -ENOMEM;
+
spin_lock_init(&d->event_lock);
if ( get_free_port(d) != 0 )
+ {
+ free_evtchn_bucket(d, d->evtchn);
return -EINVAL;
+ }
evtchn_from_port(d, 0)->state = ECS_RESERVED;
#if MAX_VIRT_CPUS > BITS_PER_LONG
d->poll_mask = xmalloc_array(unsigned long, BITS_TO_LONGS(MAX_VIRT_CPUS));
if ( !d->poll_mask )
+ {
+ free_evtchn_bucket(d, d->evtchn);
return -ENOMEM;
+ }
bitmap_zero(d->poll_mask, MAX_VIRT_CPUS);
#endif
@@ -1170,7 +1211,7 @@ int evtchn_init(struct domain *d)
void evtchn_destroy(struct domain *d)
{
- int i;
+ unsigned int i, j;
/* After this barrier no new event-channel allocations can occur. */
BUG_ON(!d->is_dying);
@@ -1185,12 +1226,17 @@ void evtchn_destroy(struct domain *d)
/* Free all event-channel buckets. */
spin_lock(&d->event_lock);
- for ( i = 0; i < NR_EVTCHN_BUCKETS; i++ )
+ for ( i = 0; i < NR_EVTCHN_GROUPS; i++ )
{
- xsm_free_security_evtchn(d->evtchn[i]);
- xfree(d->evtchn[i]);
- d->evtchn[i] = NULL;
+ if ( !d->evtchn_group[i] )
+ continue;
+ for ( j = 0; j < BUCKETS_PER_GROUP; j++ )
+ free_evtchn_bucket(d, d->evtchn_group[i][j]);
+ xfree(d->evtchn_group[i]);
+ d->evtchn_group[i] = NULL;
}
+ free_evtchn_bucket(d, d->evtchn);
+ d->evtchn = NULL;
spin_unlock(&d->event_lock);
clear_global_virq_handlers(d);
diff --git a/xen/include/xen/event.h b/xen/include/xen/event.h
index 6933f02608..cba09e7a60 100644
--- a/xen/include/xen/event.h
+++ b/xen/include/xen/event.h
@@ -69,15 +69,37 @@ int guest_enabled_event(struct vcpu *v, uint32_t virq);
/* Notify remote end of a Xen-attached event channel.*/
void notify_via_xen_event_channel(struct domain *ld, int lport);
-/* Internal event channel object accessors */
-#define bucket_from_port(d,p) \
- ((d)->evtchn[(p)/EVTCHNS_PER_BUCKET])
-#define port_is_valid(d,p) \
- (((p) >= 0) && ((p) < (d)->max_evtchns) && \
- (bucket_from_port(d,p) != NULL))
-#define evtchn_from_port(d,p) \
- (&(bucket_from_port(d,p))[(p)&(EVTCHNS_PER_BUCKET-1)])
+/*
+ * Internal event channel object storage.
+ *
+ * The objects (struct evtchn) are indexed using a two level scheme of
+ * groups and buckets. Each group is a page of bucket pointers. Each
+ * bucket is a page-sized array of struct evtchn's.
+ *
+ * The first bucket is directly accessed via d->evtchn.
+ */
+#define group_from_port(d, p) \
+ ((d)->evtchn_group[(p) / EVTCHNS_PER_GROUP])
+#define bucket_from_port(d, p) \
+ ((group_from_port(d, p))[((p) % EVTCHNS_PER_GROUP) / EVTCHNS_PER_BUCKET])
+static inline bool_t port_is_valid(struct domain *d, unsigned int p)
+{
+ if ( p >= d->max_evtchns )
+ return 0;
+ if ( !d->evtchn )
+ return 0;
+ if ( p < EVTCHNS_PER_BUCKET )
+ return 1;
+ return group_from_port(d, p) != NULL && bucket_from_port(d, p) != NULL;
+}
+
+static inline struct evtchn *evtchn_from_port(struct domain *d, unsigned int p)
+{
+ if ( p < EVTCHNS_PER_BUCKET )
+ return &d->evtchn[p];
+ return bucket_from_port(d, p) + (p % EVTCHNS_PER_BUCKET);
+}
/* Wait on a Xen-attached event channel. */
#define wait_on_xen_event_channel(port, condition) \
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index f8fc7c254a..2090a413d8 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -50,8 +50,22 @@ extern struct domain *dom0;
#else
#define BITS_PER_EVTCHN_WORD(d) (has_32bit_shinfo(d) ? 32 : BITS_PER_XEN_ULONG)
#endif
-#define EVTCHNS_PER_BUCKET 128
-#define NR_EVTCHN_BUCKETS (NR_EVENT_CHANNELS / EVTCHNS_PER_BUCKET)
+
+#define BUCKETS_PER_GROUP (PAGE_SIZE/sizeof(struct evtchn *))
+/* Round size of struct evtchn up to power of 2 size */
+#define __RDU2(x) ( (x) | ( (x) >> 1))
+#define __RDU4(x) ( __RDU2(x) | ( __RDU2(x) >> 2))
+#define __RDU8(x) ( __RDU4(x) | ( __RDU4(x) >> 4))
+#define __RDU16(x) ( __RDU8(x) | ( __RDU8(x) >> 8))
+#define __RDU32(x) (__RDU16(x) | (__RDU16(x) >>16))
+#define next_power_of_2(x) (__RDU32((x)-1) + 1)
+
+/* Maximum number of event channels for any ABI. */
+#define MAX_NR_EVTCHNS NR_EVENT_CHANNELS
+
+#define EVTCHNS_PER_BUCKET (PAGE_SIZE / next_power_of_2(sizeof(struct evtchn)))
+#define EVTCHNS_PER_GROUP (BUCKETS_PER_GROUP * EVTCHNS_PER_BUCKET)
+#define NR_EVTCHN_GROUPS DIV_ROUND_UP(MAX_NR_EVTCHNS, EVTCHNS_PER_GROUP)
struct evtchn
{
@@ -271,7 +285,8 @@ struct domain
spinlock_t rangesets_lock;
/* Event channel information. */
- struct evtchn *evtchn[NR_EVTCHN_BUCKETS];
+ struct evtchn *evtchn; /* first bucket only */
+ struct evtchn **evtchn_group[NR_EVTCHN_GROUPS]; /* all other buckets */
unsigned int max_evtchns;
spinlock_t event_lock;
const struct evtchn_port_ops *evtchn_port_ops;
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-30 06:01:07 +0000