xenpm: Add a small scheduler knob "sched_smt_power_savings"

Current scheduler only care performance, thus always picks pCPU from
the most idle package. This knob provides another option to pick pCPU from
least idle package, for user who want performance power balance.

Signed-off-by: Yu Ke <ke.yu@intel.com>
Signed-off-by: Tian Kevin <kevin.tian@intel.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/tools/misc/xenpm.c b/tools/misc/xenpm.c
index 3540ab2de8..39eef6517f 100644
--- a/tools/misc/xenpm.c
+++ b/tools/misc/xenpm.c
@@ -56,6 +56,7 @@ void show_help(void)
             " set-up-threshold      [cpuid] <num> set up threshold on CPU <cpuid> or all\n"
             "                                     it is used in ondemand governor.\n"
             " get-cpu-topology                    get thread/core/socket topology info\n"
+            " set-sched-smt           enable|disable enable/disable scheduler smt power saving\n"
             " start [seconds]                     start collect Cx/Px statistics,\n"
             "                                     output after CTRL-C or SIGINT or several seconds.\n"
             );
@@ -838,6 +839,36 @@ void cpu_topology_func(int argc, char *argv[])
     return ;
 }
 
+void set_sched_smt_func(int argc, char *argv[])
+{
+    int value, rc;
+
+    if (argc != 1){
+        show_help();
+        exit(-1);
+    }
+
+    if ( !strncmp(argv[0], "disable", sizeof("disable")) )
+    {
+        value = 0;
+    }
+    else if ( !strncmp(argv[0], "enable", sizeof("enable")) )
+    {
+        value = 1;
+    }
+    else
+    {
+        show_help();
+        exit(-1);
+    }
+
+    rc = xc_set_sched_opt_smt(xc_fd, value);
+    printf("%s sched_smt_power_savings %s\n", argv[0],
+                    rc? "failed":"successeed" );
+
+    return;
+}
+
 struct {
     const char *name;
     void (*function)(int argc, char *argv[]);
@@ -854,6 +885,7 @@ struct {
     { "set-sampling-rate", scaling_sampling_rate_func },
     { "set-up-threshold", scaling_up_threshold_func },
     { "get-cpu-topology", cpu_topology_func},
+    { "set-sched-smt", set_sched_smt_func},
 };
 
 int main(int argc, char *argv[])