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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Tue, 10 Apr 2018 12:22:16 +0200
Message-ID: <CAJZ5v0ic=bm76r=z+owZamVpb-fFxy3tqfeFvh_N2ROKpsYo=A@mail.gmail.com>
Subject: Re: [PATCH][RFC] tools/power turbostat: if --max_loop, print for
 specific time of loops
To:     Yu Chen <yu.c.chen@intel.com>
Cc:     Len Brown <lenb@kernel.org>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Artem Bityutskiy <artem.bityutskiy@intel.com>,
        Linux PM <linux-pm@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, Apr 10, 2018 at 12:18 PM, Yu Chen <yu.c.chen@intel.com> wrote:
> From: Chen Yu <yu.c.chen@intel.com>
>
> There's a use case during test to only print specific round of loops
> if --interval is specified, for example, with this patch applied:
>
> turbostat -i 5 --max_loops 4
> will capture 4 samples with 5 seconds interval.

Why --max_loops and not just --loops or --iterations?

> Signed-off-by: Chen Yu <yu.c.chen@intel.com>
> ---
>  tools/power/x86/turbostat/turbostat.c | 19 ++++++++++++++++++-
>  1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
> index bd9c6b31a504..a35418a59468 100644
> --- a/tools/power/x86/turbostat/turbostat.c
> +++ b/tools/power/x86/turbostat/turbostat.c
> @@ -48,6 +48,7 @@ char *proc_stat = "/proc/stat";
>  FILE *outf;
>  int *fd_percpu;
>  struct timespec interval_ts = {5, 0};
> +unsigned int max_loops;
>  unsigned int debug;
>  unsigned int quiet;
>  unsigned int sums_need_wide_columns;
> @@ -470,6 +471,7 @@ void help(void)
>         "               {core | package | j,k,l..m,n-p }\n"
>         "--quiet        skip decoding system configuration header\n"
>         "--interval sec Override default 5-second measurement interval\n"
> +       "--max_loops times      The number of loops if interval is specified\n"
>         "--help         print this help message\n"
>         "--list         list column headers only\n"
>         "--out file     create or truncate \"file\" for all output\n"
> @@ -2565,6 +2567,7 @@ void turbostat_loop()
>  {
>         int retval;
>         int restarted = 0;
> +       int loops = 0;
>
>  restart:
>         restarted++;
> @@ -2583,6 +2586,7 @@ void turbostat_loop()
>         restarted = 0;
>         gettimeofday(&tv_even, (struct timezone *)NULL);
>
> +       loops = 0;
>         while (1) {
>                 if (for_all_proc_cpus(cpu_is_not_present)) {
>                         re_initialize();
> @@ -2626,6 +2630,9 @@ void turbostat_loop()
>                 compute_average(ODD_COUNTERS);
>                 format_all_counters(ODD_COUNTERS);
>                 flush_output_stdout();
> +
> +               if (++loops >= (max_loops/2))
> +                       break;
>         }
>  }
>
> @@ -5009,12 +5016,13 @@ void cmdline(int argc, char **argv)
>                 {"Summary",     no_argument,            0, 'S'},
>                 {"TCC",         required_argument,      0, 'T'},
>                 {"version",     no_argument,            0, 'v' },
> +               {"max_loops",   required_argument,      0, 'x'},
>                 {0,             0,                      0,  0 }
>         };
>
>         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:JM:m:o:qST:vx:",
>                                 long_options, &option_index)) != -1) {
>                 switch (opt) {
>                 case 'a':
> @@ -5076,6 +5084,15 @@ void cmdline(int argc, char **argv)
>                         print_version();
>                         exit(0);
>                         break;
> +               case 'x':
> +                       {
> +                               unsigned int loops = strtod(optarg, NULL);
> +
> +                               if (loops % 2)
> +                                       loops++;
> +                               max_loops = loops;
> +                       }
> +                       break;
>                 }
>         }
>  }
> --
> 2.13.6
>