File 5587d7e2-evtchn-pad-struct-evtchn-to-64-bytes.patch of Package xen.6117

# Commit b58214a24231a1f2a7e09ae9cc3014eff752918b
# Date 2015-06-22 11:39:46 +0200
# Author David Vrabel <david.vrabel@citrix.com>
# Committer Jan Beulich <jbeulich@suse.com>
evtchn: pad struct evtchn to 64 bytes

The number of struct evtchn in a page must be a power of two.  Under
some workloads performance is improved slightly by padding struct
evtchn to 64 bytes (a typical cache line size), thus putting the fewer
per-channel locks into each cache line.

This does not decrease the number of struct evtchn's per-page.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -130,7 +130,7 @@ struct evtchn
 #endif
     } ssid;
 #endif
-};
+} __attribute__((aligned(64)));
 
 int  evtchn_init(struct domain *d); /* from domain_create */
 void evtchn_destroy(struct domain *d); /* from domain_kill */