[PATCH 04/11] evtchn: use a per-domain variable for the max number of event channels

[David Vrabel <david.vrabel@citrix.com>]

From: David Vrabel <david.vrabel@citrix.com>

Instead of the MAX_EVTCHNS(d) macro, use d->max_evtchns instead.  This
avoids having to repeatedly check the ABI type.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
 xen/common/event_2l.c      |    1 +
 xen/common/event_channel.c |    4 ++--
 xen/common/schedule.c      |    2 +-
 xen/include/xen/event.h    |    2 +-
 xen/include/xen/sched.h    |    2 +-
 5 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/xen/common/event_2l.c b/xen/common/event_2l.c
index 5c27eab..add37e4 100644
--- a/xen/common/event_2l.c
+++ b/xen/common/event_2l.c
@@ -96,6 +96,7 @@ static const struct evtchn_port_ops evtchn_port_ops_2l =
 void evtchn_2l_init(struct domain *d)
 {
     d->evtchn_port_ops = &evtchn_port_ops_2l;
+    d->max_evtchns = BITS_PER_EVTCHN_WORD(d) * BITS_PER_EVTCHN_WORD(d);
 }
 
 /*
diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index f73c7a9..539a198 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -134,7 +134,7 @@ static int get_free_port(struct domain *d)
         if ( evtchn_from_port(d, port)->state == ECS_FREE )
             return port;
 
-    if ( port == MAX_EVTCHNS(d) )
+    if ( port == d->max_evtchns )
         return -ENOSPC;
 
     chn = xzalloc_array(struct evtchn, EVTCHNS_PER_BUCKET);
@@ -1236,7 +1236,7 @@ static void domain_dump_evtchn_info(struct domain *d)
 
     spin_lock(&d->event_lock);
 
-    for ( port = 1; port < MAX_EVTCHNS(d); ++port )
+    for ( port = 1; port < d->max_evtchns; ++port )
     {
         const struct evtchn *chn;
         char *ssid;
diff --git a/xen/common/schedule.c b/xen/common/schedule.c
index 7e6884d..a5a0010 100644
--- a/xen/common/schedule.c
+++ b/xen/common/schedule.c
@@ -748,7 +748,7 @@ static long do_poll(struct sched_poll *sched_poll)
             goto out;
 
         rc = -EINVAL;
-        if ( port >= MAX_EVTCHNS(d) )
+        if ( port >= d->max_evtchns )
             goto out;
 
         rc = 0;
diff --git a/xen/include/xen/event.h b/xen/include/xen/event.h
index 2445562..6933f02 100644
--- a/xen/include/xen/event.h
+++ b/xen/include/xen/event.h
@@ -73,7 +73,7 @@ void notify_via_xen_event_channel(struct domain *ld, int lport);
 #define bucket_from_port(d,p) \
     ((d)->evtchn[(p)/EVTCHNS_PER_BUCKET])
 #define port_is_valid(d,p)    \
-    (((p) >= 0) && ((p) < MAX_EVTCHNS(d)) && \
+    (((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)])
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index fb9cf11..cb9604a 100644
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -50,7 +50,6 @@ extern struct domain *dom0;
 #else
 #define BITS_PER_EVTCHN_WORD(d) (has_32bit_shinfo(d) ? 32 : BITS_PER_XEN_ULONG)
 #endif
-#define MAX_EVTCHNS(d) (BITS_PER_EVTCHN_WORD(d) * BITS_PER_EVTCHN_WORD(d))
 #define EVTCHNS_PER_BUCKET 128
 #define NR_EVTCHN_BUCKETS  (NR_EVENT_CHANNELS / EVTCHNS_PER_BUCKET)
 
@@ -273,6 +272,7 @@ struct domain
 
     /* Event channel information. */
     struct evtchn   *evtchn[NR_EVTCHN_BUCKETS];
+    unsigned int     max_evtchns;
     spinlock_t       event_lock;
     const struct evtchn_port_ops *evtchn_port_ops;
 
-- 
1.7.2.5