From: David Vrabel <david.vrabel@citrix.com>
Date: Thu, 18 Jun 2015 12:54:25 +0000 (+0200)
Subject: evtchn: remove the locking when unmasking an event channel
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=e156654d4eb2fdeb524e6b40838767a5dc918966;p=people%2Fliuw%2Flibxenctrl-split%2Fxen.git

evtchn: remove the locking when unmasking an event channel

The event channel lock is no longer required to check if the port is
valid.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
---

diff --git a/xen/common/event_channel.c b/xen/common/event_channel.c
index fd48646a26..2208de0163 100644
--- a/xen/common/event_channel.c
+++ b/xen/common/event_channel.c
@@ -927,8 +927,6 @@ int evtchn_unmask(unsigned int port)
     struct domain *d = current->domain;
     struct evtchn *evtchn;
 
-    ASSERT(spin_is_locked(&d->event_lock));
-
     if ( unlikely(!port_is_valid(d, port)) )
         return -EINVAL;
 
@@ -1095,9 +1093,7 @@ long do_event_channel_op(int cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
         struct evtchn_unmask unmask;
         if ( copy_from_guest(&unmask, arg, 1) != 0 )
             return -EFAULT;
-        spin_lock(&current->domain->event_lock);
         rc = evtchn_unmask(unmask.port);
-        spin_unlock(&current->domain->event_lock);
         break;
     }