On Thu, 14 Aug 2014, John Kacur wrote:
> Some people running cyclictest on laptops don't want to automatically
> take advantage of the trick that prevents the power management to
> transistion to high cstates, since it eats up their battery power.
>
> Allow them to suppress this feature with --laptop
>
> This will result in power latency results of course.
The above should read: "This will result in poorer latency results of
course."
>
> Feature-requested-by: Joakim Hernberg <jhernberg@xxxxxxxxxx>
> Signed-off-by: John Kacur <jkacur@xxxxxxxxxx>
> ---
> src/cyclictest/cyclictest.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index b45041e01f3a..a3e7b1d6c377 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -186,6 +186,7 @@ static int use_fifo = 0;
> static pthread_t fifo_threadid;
> static int aligned = 0;
> static int offset = 0;
> +static int laptop = 0;
>
> static pthread_cond_t refresh_on_max_cond = PTHREAD_COND_INITIALIZER;
> static pthread_mutex_t refresh_on_max_lock = PTHREAD_MUTEX_INITIALIZER;
> @@ -235,6 +236,11 @@ static void set_latency_target(void)
> struct stat s;
> int err;
>
> + if (laptop) {
> + warn("not setting cpu_dma_latency to save battery power\n");
> + return;
> + }
> +
> errno = 0;
> err = stat("/dev/cpu_dma_latency", &s);
> if (err == -1) {
> @@ -1020,6 +1026,9 @@ static void display_help(int error)
> "-i INTV --interval=INTV base interval of thread in us default=1000\n"
> "-I --irqsoff Irqsoff tracing (used with -b)\n"
> "-l LOOPS --loops=LOOPS number of loops: default=0(endless)\n"
> + " --laptop Save battery when running cyclictest\n"
> + " This will give you poorer realtime results\n"
> + " but will not drain your battery so quickly\n"
> "-m --mlockall lock current and future memory allocations\n"
> "-M --refresh_on_max delay updating the screen until a new max latency is hit\n"
> "-n --nanosleep use clock_nanosleep\n"
> @@ -1183,7 +1192,7 @@ enum option_values {
> OPT_QUIET, OPT_PRIOSPREAD, OPT_RELATIVE, OPT_RESOLUTION, OPT_SYSTEM,
> OPT_SMP, OPT_THREADS, OPT_TRACER, OPT_UNBUFFERED, OPT_NUMA, OPT_VERBOSE,
> OPT_WAKEUP, OPT_WAKEUPRT, OPT_DBGCYCLIC, OPT_POLICY, OPT_HELP, OPT_NUMOPTS,
> - OPT_ALIGNED,
> + OPT_ALIGNED, OPT_LAPTOP,
> };
>
> /* Process commandline options */
> @@ -1216,6 +1225,7 @@ static void process_options (int argc, char *argv[], int max_cpus)
> {"histofall", required_argument, NULL, OPT_HISTOFALL },
> {"interval", required_argument, NULL, OPT_INTERVAL },
> {"irqsoff", no_argument, NULL, OPT_IRQSOFF },
> + {"laptop", no_argument, NULL, OPT_LAPTOP },
> {"loops", required_argument, NULL, OPT_LOOPS },
> {"mlockall", no_argument, NULL, OPT_MLOCKALL },
> {"refresh_on_max", no_argument, NULL, OPT_REFRESH },
> @@ -1445,6 +1455,8 @@ static void process_options (int argc, char *argv[], int max_cpus)
> handlepolicy(optarg); break;
> case OPT_DBGCYCLIC:
> ct_debug = 1; break;
> + case OPT_LAPTOP:
> + laptop = 1; break;
> }
> }
>
> --
> 1.8.1.4
>
>
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