John Kacur <jkacur@xxxxxxxxxx> writes:
> This patch add the long option --default-system
> --default-system runs cyclictest without attempting any tuning.
> Power management is not suppressed so cyclictest measures the system as
> it is configured.
>
> This is effectively the same as --laptop, but makes it clear to the user
> what is done and why.
>
> Signed-off-by: John Kacur <jkacur@xxxxxxxxxx>
I suppose this is probably the best that can be done without breaking
compatibility.
One comment about a pre-existing issue in the code below.
> ---
> src/cyclictest/cyclictest.8 | 3 +++
> src/cyclictest/cyclictest.c | 15 ++++++++++++++-
> 2 files changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/src/cyclictest/cyclictest.8 b/src/cyclictest/cyclictest.8
> index dc0a278f3d30..dcae5b83147f 100644
> --- a/src/cyclictest/cyclictest.8
> +++ b/src/cyclictest/cyclictest.8
> @@ -59,6 +59,9 @@ select clock
> .br
> 1 = CLOCK_REALTIME
> .TP
> +.B \-\-default\-system
> +Don't attempt to tune the system from cyclictest. Power management is not suppressed. This might give poorer results, but will allow you to discover if you need to tune the system.
> +.TP
> .B \-d, \-\-distance=DIST
> Distance of thread intervals in us, default = 500
> .TP
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index 067b75317c9a..cbdc6c11ffe3 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -194,6 +194,7 @@ static int ct_debug;
> static int use_fifo = 0;
> static pthread_t fifo_threadid;
> static int laptop = 0;
> +static int power_management = 0;
> static int use_histfile = 0;
>
> #ifdef ARCH_HAS_SMI_COUNTER
> @@ -256,6 +257,11 @@ static void set_latency_target(void)
> return;
> }
>
> + if (power_management) {
> + warn("not setting cpu_dma_latency from cyclictest\n");
> + return;
> + }
> +
> errno = 0;
> err = stat("/dev/cpu_dma_latency", &s);
> if (err == -1) {
> @@ -820,6 +826,10 @@ static void display_help(int error)
> "-c CLOCK --clock=CLOCK select clock\n"
> " 0 = CLOCK_MONOTONIC (default)\n"
> " 1 = CLOCK_REALTIME\n"
> + " --default-system Don't attempt to tune the system from cyclictest.\n"
> + " Power management is not suppressed.\n"
> + " This might give poorer results, but will allow you\n"
> + " to discover if you need to tune the system\n"
> "-d DIST --distance=DIST distance of thread intervals in us, default=500\n"
> "-D --duration=TIME specify a length for the test run.\n"
> " Append 'm', 'h', or 'd' to specify minutes, hours or days.\n"
> @@ -947,7 +957,7 @@ static char *policyname(int policy)
>
> enum option_values {
> OPT_AFFINITY=1, OPT_BREAKTRACE, OPT_CLOCK,
> - OPT_DISTANCE, OPT_DURATION, OPT_LATENCY,
> + OPT_DEFAULT_SYSTEM, OPT_DISTANCE, OPT_DURATION, OPT_LATENCY,
> OPT_FIFO, OPT_HISTOGRAM, OPT_HISTOFALL, OPT_HISTFILE,
> OPT_INTERVAL, OPT_JSON, OPT_MAINAFFINITY, OPT_LOOPS, OPT_MLOCKALL,
> OPT_REFRESH, OPT_NANOSLEEP, OPT_NSECS, OPT_OSCOPE, OPT_PRIORITY,
> @@ -976,6 +986,7 @@ static void process_options(int argc, char *argv[], int max_cpus)
> {"aligned", optional_argument, NULL, OPT_ALIGNED },
> {"breaktrace", required_argument, NULL, OPT_BREAKTRACE },
> {"clock", required_argument, NULL, OPT_CLOCK },
> + {"default-system", no_argument, NULL, OPT_DEFAULT_SYSTEM },
> {"distance", required_argument, NULL, OPT_DISTANCE },
> {"duration", required_argument, NULL, OPT_DURATION },
> {"latency", required_argument, NULL, OPT_LATENCY },
> @@ -1061,6 +1072,8 @@ static void process_options(int argc, char *argv[], int max_cpus)
> case OPT_CLOCK:
> clocksel = atoi(optarg); break;
> case 'C':
The case for the short option 'C' should be dropped. It seems to be a
left-over from a previous cleanup. Same for 'E' a bit further down in
the switch statement.
> + case OPT_DEFAULT_SYSTEM:
> + power_management = 1; break;
> case 'd':
> case OPT_DISTANCE:
> distance = atoi(optarg); break;
