From c8cfc3c6bf404b0f110631d5bba234982e6ad24f Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Tue, 27 Nov 2012 13:17:48 +0100 Subject: cpupower: Provide -c param for cpupower monitor to schedule process on all cores If an MSR based monitor is run in parallel this is not needed. This is the default case on all/most Intel machines. But when only sysfs info is read via cpupower monitor -m Idle_Stats (typically the case for non root users) or when other monitors are PCI based (AMD), Idle_Stats, read from sysfs can be totally bogus: cpupower monitor -m Idle_Stats PKG |CORE|CPU | POLL | C1-N | C3-N | C6-N 0| 0| 0| 0.00| 0.00| 0.24| 99.81 0| 0| 32| 0.00| 0.00| 0.00| 100.7 ... 0| 17| 20| 0.00| 0.00| 0.00| 173.1 0| 17| 52| 0.00| 0.00| 0.07| 173.0 0| 18| 68| 0.00| 0.00| 0.00| 0.00 0| 18| 76| 0.00| 0.00| 0.00| 0.00 ... With the -c option all cores are woken up and the kernel did update cpuidle statistics before reading out sysfs. This causes some overhead. Therefore avoid if possible, use if needed: cpupower monitor -c -m Idle_Stats PKG |CORE|CPU | POLL | C1-N | C3-N | C6-N 0| 0| 0| 0.00| 0.00| 0.00| 100.2 0| 0| 32| 0.00| 0.00| 0.00| 100.2 ... 0| 8| 8| 0.00| 0.00| 0.00| 99.82 0| 8| 40| 0.00| 0.00| 0.00| 99.81 0| 9| 24| 0.00| 0.00| 0.00| 100.3 0| 9| 56| 0.00| 0.00| 0.00| 100.2 0| 16| 4| 0.00| 0.00| 0.00| 99.75 0| 16| 36| 0.00| 0.00| 0.00| 99.38 ... Signed-off-by: Thomas Renninger Signed-off-by: Rafael J. Wysocki --- tools/power/cpupower/man/cpupower-monitor.1 | 15 +++++++++++++-- tools/power/cpupower/utils/helpers/helpers.h | 1 + .../cpupower/utils/idle_monitor/cpupower-monitor.c | 18 +++++++++++++++++- .../cpupower/utils/idle_monitor/cpupower-monitor.h | 17 +++++++++++++++++ 4 files changed, 48 insertions(+), 3 deletions(-) (limited to 'tools') diff --git a/tools/power/cpupower/man/cpupower-monitor.1 b/tools/power/cpupower/man/cpupower-monitor.1 index 1141c2073719..e01c35d13b6e 100644 --- a/tools/power/cpupower/man/cpupower-monitor.1 +++ b/tools/power/cpupower/man/cpupower-monitor.1 @@ -7,11 +7,11 @@ cpupower\-monitor \- Report processor frequency and idle statistics .RB "\-l" .B cpupower monitor -.RB [ "\-m ," [ ",..." ] ] +.RB [ -c ] [ "\-m ," [ ",..." ] ] .RB [ "\-i seconds" ] .br .B cpupower monitor -.RB [ "\-m ," [ ",..." ] ] +.RB [ -c ][ "\-m ," [ ",..." ] ] .RB command .br .SH DESCRIPTION @@ -64,6 +64,17 @@ Only display specific monitors. Use the monitor string(s) provided by \-l option Measure intervall. .RE .PP +\-c +.RS 4 +Schedule the process on every core before starting and ending measuring. +This could be needed for the Idle_Stats monitor when no other MSR based +monitor (has to be run on the core that is measured) is run in parallel. +This is to wake up the processors from deeper sleep states and let the +kernel re +-account its cpuidle (C-state) information before reading the +cpuidle timings from sysfs. +.RE +.PP command .RS 4 Measure idle and frequency characteristics of an arbitrary command/workload. diff --git a/tools/power/cpupower/utils/helpers/helpers.h b/tools/power/cpupower/utils/helpers/helpers.h index f84985f630e2..aa9e95486a2d 100644 --- a/tools/power/cpupower/utils/helpers/helpers.h +++ b/tools/power/cpupower/utils/helpers/helpers.h @@ -114,6 +114,7 @@ struct cpupower_topology { extern int get_cpu_topology(struct cpupower_topology *cpu_top); extern void cpu_topology_release(struct cpupower_topology cpu_top); + /* CPU topology/hierarchy parsing ******************/ /* X86 ONLY ****************************************/ diff --git a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c index 7a657f3da23b..c4bae9203a69 100644 --- a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c +++ b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c @@ -39,6 +39,7 @@ static int mode; static int interval = 1; static char *show_monitors_param; static struct cpupower_topology cpu_top; +static unsigned int wake_cpus; /* ToDo: Document this in the manpage */ static char range_abbr[RANGE_MAX] = { 'T', 'C', 'P', 'M', }; @@ -314,16 +315,28 @@ int fork_it(char **argv) int do_interval_measure(int i) { unsigned int num; + int cpu; + + if (wake_cpus) + for (cpu = 0; cpu < cpu_count; cpu++) + bind_cpu(cpu); for (num = 0; num < avail_monitors; num++) { dprint("HW C-state residency monitor: %s - States: %d\n", monitors[num]->name, monitors[num]->hw_states_num); monitors[num]->start(); } + sleep(i); + + if (wake_cpus) + for (cpu = 0; cpu < cpu_count; cpu++) + bind_cpu(cpu); + for (num = 0; num < avail_monitors; num++) monitors[num]->stop(); + return 0; } @@ -332,7 +345,7 @@ static void cmdline(int argc, char *argv[]) int opt; progname = basename(argv[0]); - while ((opt = getopt(argc, argv, "+li:m:")) != -1) { + while ((opt = getopt(argc, argv, "+lci:m:")) != -1) { switch (opt) { case 'l': if (mode) @@ -351,6 +364,9 @@ static void cmdline(int argc, char *argv[]) mode = show; show_monitors_param = optarg; break; + case 'c': + wake_cpus = 1; + break; default: print_wrong_arg_exit(); } diff --git a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.h b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.h index 9312ee1f2dbc..9e43f3371fbc 100644 --- a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.h +++ b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.h @@ -65,4 +65,21 @@ extern long long timespec_diff_us(struct timespec start, struct timespec end); "could be inaccurate\n"), mes, ov); \ } + +/* Taken over from x86info project sources -> return 0 on success */ +#include +#include +#include +static inline int bind_cpu(int cpu) +{ + cpu_set_t set; + + if (sched_getaffinity(getpid(), sizeof(set), &set) == 0) { + CPU_ZERO(&set); + CPU_SET(cpu, &set); + return sched_setaffinity(getpid(), sizeof(set), &set); + } + return 1; +} + #endif /* __CPUIDLE_INFO_HW__ */ -- cgit v1.2.3-59-g8ed1b