[PATCH 9/9] xen: sched: per-core runqueues as default in credit2

[Dario Faggioli <dario.faggioli@citrix.com>]

Experiments have shown that arranging the scheduing
runqueues on a per-core basis yields better results,
in most cases.

Such evaluation has been done, for the first time,
by Uma Sharma, during her participation to OPW. Some
of the results she got are summarized here:

 http://lists.xen.org/archives/html/xen-devel/2015-03/msg01499.html

Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Signed-off-by: Uma Sharma <uma.sharma523@gmail.com>
---
Cc: George Dunlap <george.dunlap@eu.citrix.com>
Cc: Uma Sharma <uma.sharma523@gmail.com>
---
 docs/misc/xen-command-line.markdown |    2 +-
 xen/common/sched_credit2.c          |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/misc/xen-command-line.markdown b/docs/misc/xen-command-line.markdown
index 71315b8..8fc9cd7 100644
--- a/docs/misc/xen-command-line.markdown
+++ b/docs/misc/xen-command-line.markdown
@@ -470,7 +470,7 @@ combination with the `low_crashinfo` command line option.
 ### credit2\_runqueue
 > `= socket | core`
 
-> Default: `socket`
+> Default: `core`
 
 Specify how host CPUs are arranged in runqueues. Runqueues are kept
 balanced with respect to the load generated by the vCPUs running on
diff --git a/xen/common/sched_credit2.c b/xen/common/sched_credit2.c
index 025626f..0e9e722 100644
--- a/xen/common/sched_credit2.c
+++ b/xen/common/sched_credit2.c
@@ -211,7 +211,7 @@ integer_param("credit2_balance_over", opt_overload_balance_tolerance);
  */
 #define OPT_RUNQUEUE_CORE   1
 #define OPT_RUNQUEUE_SOCKET 2
-static int __read_mostly opt_runqueue = OPT_RUNQUEUE_SOCKET;
+static int __read_mostly opt_runqueue = OPT_RUNQUEUE_CORE;
 
 static void parse_credit2_runqueue(const char *s)
 {