tools/power turbostat: stop migrating, unless '-m'

Turbostat has the capability to set its own affinity to
each CPU so that its MSR accesses are on the local CPU.

However, using the in-kernel cross-call in  the msr driver
tends to be less invasive, so do that -- by-default.
'-m' remains to get the old behaviour.

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 6f7c64acee23..1a3a5b436b80 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -92,6 +92,7 @@ unsigned int do_ring_perf_limit_reasons;
 unsigned int crystal_hz;
 unsigned long long tsc_hz;
 int base_cpu;
+int do_migrate;
 double discover_bclk(unsigned int family, unsigned int model);
 unsigned int has_hwp;   /* IA32_PM_ENABLE, IA32_HWP_CAPABILITIES */
                         /* IA32_HWP_REQUEST, IA32_HWP_STATUS */
@@ -302,6 +303,9 @@ int for_all_cpus(int (func)(struct thread_data *, struct core_data *, struct pkg
 
 int cpu_migrate(int cpu)
 {
+        if (!do_migrate)
+                return 0;
+
         CPU_ZERO_S(cpu_affinity_setsize, cpu_affinity_set);
         CPU_SET_S(cpu, cpu_affinity_setsize, cpu_affinity_set);
         if (sched_setaffinity(0, cpu_affinity_setsize, cpu_affinity_set) == -1)
@@ -5000,6 +5004,7 @@ void cmdline(int argc, char **argv)
                 {"hide",        required_argument,      0, 'H'},        // meh, -h taken by --help
                 {"Joules",      no_argument,            0, 'J'},
                 {"list",        no_argument,            0, 'l'},
+                {"migrate",     no_argument,            0, 'm'},
                 {"out",         required_argument,      0, 'o'},
                 {"quiet",       no_argument,            0, 'q'},
                 {"show",        required_argument,      0, 's'},
@@ -5011,7 +5016,7 @@ void cmdline(int argc, char **argv)
 
         progname = argv[0];
 
-        while ((opt = getopt_long_only(argc, argv, "+C:c:Ddhi:JM:m:o:qST:v",
+        while ((opt = getopt_long_only(argc, argv, "+C:c:Ddhi:Jmo:qST:v",
                                 long_options, &option_index)) != -1) {
                 switch (opt) {
                 case 'a':
@@ -5054,6 +5059,9 @@ void cmdline(int argc, char **argv)
                         list_header_only++;
                         quiet++;
                         break;
+                case 'm':
+                        do_migrate = 1;
+                        break;
                 case 'o':
                         outf = fopen_or_die(optarg, "w");
                         break;