[PATCH][v4] tools/power turbostat: if --iterations, print for specific time of iterations

[Yu Chen]

From: Chen Yu <yu.c.c...@intel.com>

There's a use case during test to only print specific round of iterations
if --iterations is specified, for example, with this patch applied:

turbostat -i 5 -I 4
will capture 4 samples with 5 seconds interval.

Cc: Len Brown <l...@kernel.org>
Cc: Rafael J Wysocki <r...@rjwysocki.net>
Cc: Artem Bityutskiy <artem.bityuts...@intel.com>
Cc: Doug Smythies <dsmyth...@telus.net>
Cc: linux...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Chen Yu <yu.c.c...@intel.com>
---
 tools/power/x86/turbostat/turbostat.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c 
b/tools/power/x86/turbostat/turbostat.c
index bd9c6b31a504..a2fe96f038f0 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};
+int iterations;
 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"
+       "--iterations count     Number of measurement iterations(requires 
'--interval'\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 done_iters = 0;
 
 restart:
        restarted++;
@@ -2581,6 +2584,7 @@ void turbostat_loop()
                goto restart;
        }
        restarted = 0;
+       done_iters = 0;
        gettimeofday(&tv_even, (struct timezone *)NULL);
 
        while (1) {
@@ -2607,6 +2611,10 @@ void turbostat_loop()
                compute_average(EVEN_COUNTERS);
                format_all_counters(EVEN_COUNTERS);
                flush_output_stdout();
+
+               if (iterations && (++done_iters >= iterations))
+                       break;
+
                nanosleep(&interval_ts, NULL);
                if (snapshot_proc_sysfs_files())
                        goto restart;
@@ -2626,6 +2634,9 @@ void turbostat_loop()
                compute_average(ODD_COUNTERS);
                format_all_counters(ODD_COUNTERS);
                flush_output_stdout();
+
+               if (iterations && (++done_iters >= iterations))
+                       break;
        }
 }
 
@@ -4999,6 +5010,7 @@ void cmdline(int argc, char **argv)
                {"Dump",        no_argument,            0, 'D'},
                {"debug",       no_argument,            0, 'd'},        /* 
internal, not documented */
                {"interval",    required_argument,      0, 'i'},
+               {"iterations",  required_argument,      0, 'I'},
                {"help",        no_argument,            0, 'h'},
                {"hide",        required_argument,      0, 'H'},        // meh, 
-h taken by --help
                {"Joules",      no_argument,            0, 'J'},
@@ -5014,7 +5026,7 @@ void cmdline(int argc, char **argv)
 
        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:i:JM:m:o:qST:v",
                                long_options, &option_index)) != -1) {
                switch (opt) {
                case 'a':
@@ -5036,6 +5048,15 @@ void cmdline(int argc, char **argv)
                default:
                        help();
                        exit(1);
+               case 'I':
+                       iterations = strtod(optarg, NULL);
+
+                       if (iterations <= 0) {
+                               fprintf(outf, "iterations %d should be positive 
number\n",
+                                       iterations);
+                               exit(2);
+                       }
+                       break;
                case 'i':
                        {
                                double interval = strtod(optarg, NULL);
-- 
2.13.6