From d0e4a193c33adaa4f91128d5393aa3589c2f3e9e Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Mon, 31 Jul 2017 07:56:06 -0400 Subject: tools/power/cpupower: allow running without cpu0 Linux-3.7 added CONFIG_BOOTPARAM_HOTPLUG_CPU0, allowing systems to offline cpu0. But when cpu0 is offline, cpupower monitor will not display all processor and Mperf information: [root@intel-skylake-dh-03 cpupower]# ./cpupower monitor WARNING: at least one cpu is offline |Idle_Stats CPU | POLL | C1-S | C1E- | C3-S | C6-S | C7s- | C8-S 4| 0.00| 0.00| 0.00| 0.00| 0.90| 0.00| 96.13 1| 0.00| 0.00| 5.49| 0.00| 0.01| 0.00| 92.26 5| 0.00| 0.00| 0.00| 0.00| 0.46| 0.00| 99.50 2| 45.42| 0.00| 0.00| 0.00| 22.94| 0.00| 28.84 6| 0.00| 37.54| 0.00| 0.00| 0.00| 0.00| 0.00 3| 0.00| 0.00| 0.00| 0.00| 0.30| 0.00| 91.99 7| 0.00| 0.00| 0.00| 0.00| 4.70| 0.00| 0.70 This patch replaces the hard-coded use of cpu0 in cpupower with the current cpu, allowing it to run without a cpu0. After the patch is applied, [root@intel-skylake-dh-03 cpupower]# ./cpupower monitor WARNING: at least one cpu is offline |Nehalem || Mperf || Idle_Stats CPU | C3 | C6 | PC3 | PC6 || C0 | Cx | Freq || POLL | C1-S | C1E- | C3-S | C6-S | C7s- | C8-S 4| 0.01| 1.27| 0.00| 0.00|| 0.04| 99.96| 3957|| 0.00| 0.00| 0.00| 0.00| 1.43| 0.00| 98.52 1| 0.00| 98.82| 0.00| 0.00|| 0.05| 99.95| 3361|| 0.00| 0.00| 0.01| 0.00| 0.03| 0.00| 99.88 5| 0.00| 98.82| 0.00| 0.00|| 0.09| 99.91| 3917|| 0.00| 0.00| 0.00| 0.00| 99.38| 0.00| 0.50 2| 0.33| 0.00| 0.00| 0.00|| 0.00|100.00| 3890|| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00|100.00 6| 0.33| 0.00| 0.00| 0.00|| 0.01| 99.99| 3903|| 0.00| 0.00| 0.00| 0.00| 0.00| 0.00| 99.99 3| 0.01| 0.71| 0.00| 0.00|| 0.06| 99.94| 3678|| 0.00| 0.00| 0.00| 0.00| 0.80| 0.00| 99.13 7| 0.01| 0.71| 0.00| 0.00|| 0.03| 99.97| 3538|| 0.00| 0.69| 11.70| 0.00| 0.00| 0.00| 87.57 There are some minor cleanups included in this patch. Signed-off-by: Prarit Bhargava Signed-off-by: Thomas Renninger Signed-off-by: Rafael J. Wysocki --- tools/power/cpupower/utils/cpupower.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'tools/power/cpupower/utils/cpupower.c') diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c index 9ea914378985..2dccf4998599 100644 --- a/tools/power/cpupower/utils/cpupower.c +++ b/tools/power/cpupower/utils/cpupower.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -31,6 +32,7 @@ static int cmd_help(int argc, const char **argv); */ struct cpupower_cpu_info cpupower_cpu_info; int run_as_root; +int base_cpu; /* Affected cpus chosen by -c/--cpu param */ struct bitmask *cpus_chosen; @@ -174,6 +176,7 @@ int main(int argc, const char *argv[]) unsigned int i, ret; struct stat statbuf; struct utsname uts; + char pathname[32]; cpus_chosen = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF)); @@ -198,17 +201,23 @@ int main(int argc, const char *argv[]) argv[0] = cmd = "help"; } - get_cpu_info(0, &cpupower_cpu_info); + base_cpu = sched_getcpu(); + if (base_cpu < 0) { + fprintf(stderr, _("No valid cpus found.\n")); + return EXIT_FAILURE; + } + + get_cpu_info(&cpupower_cpu_info); run_as_root = !geteuid(); if (run_as_root) { ret = uname(&uts); + sprintf(pathname, "/dev/cpu/%d/msr", base_cpu); if (!ret && !strcmp(uts.machine, "x86_64") && - stat("/dev/cpu/0/msr", &statbuf) != 0) { + stat(pathname, &statbuf) != 0) { if (system("modprobe msr") == -1) fprintf(stderr, _("MSR access not available.\n")); } } - for (i = 0; i < ARRAY_SIZE(commands); i++) { struct cmd_struct *p = commands + i; -- cgit v1.2.3