tools/power turbostat: use tsc_tweak everwhere it is needed
authorLen Brown <len.brown@intel.com>
Fri, 10 Feb 2017 05:29:51 +0000 (00:29 -0500)
committerLen Brown <len.brown@intel.com>
Wed, 1 Mar 2017 05:14:13 +0000 (00:14 -0500)
The CPU ticks at a rate in the "bus clock" domain.
eg. 100 MHz * bus_ratio.

On newer processors, the TSC has been moved out of this BCLK
domain and into a separate crystal-clock domain.

While the TSC ticks "close to" the base frequency, those that look
closely at the numbers will notice small errors in calculations that
mix units of TSC clocks and bus clocks.

"tsc_tweak" was introduced to address the most visible
mixing -- the %Busy and the the Busy_MHz calculations.
(A simplification as since removed TSC from the BusyMHz calculation)

Here we apply the tsc_tweak to everyplace where BCLK
and TSC units are mixed.  The results is that
on a system which is 100% idle, the sum of the C-states
are now much more likely to be closer to 100%.

Reported-by: Travis Downs <travis.downs@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>
tools/power/x86/turbostat/turbostat.c

index 6867557596afcc5f408498faa86e770a6540d712..bbdf9ba9d41ba348e1bc6d07e12eb641cb6d59a7 100644 (file)
@@ -680,7 +680,7 @@ int dump_counters(struct thread_data *t, struct core_data *c,
 int format_counters(struct thread_data *t, struct core_data *c,
        struct pkg_data *p)
 {
-       double interval_float;
+       double interval_float, tsc;
        char *fmt8;
        int i;
        struct msr_counter *mp;
@@ -695,6 +695,8 @@ int format_counters(struct thread_data *t, struct core_data *c,
 
        interval_float = tv_delta.tv_sec + tv_delta.tv_usec/1000000.0;
 
+       tsc = t->tsc * tsc_tweak;
+
        /* topo columns, print blanks on 1st (average) line */
        if (t == &average.threads) {
                if (DO_BIC(BIC_Package))
@@ -725,14 +727,14 @@ int format_counters(struct thread_data *t, struct core_data *c,
                        1.0 / units * t->aperf / interval_float);
 
        if (DO_BIC(BIC_Busy))
-               outp += sprintf(outp, "\t%.2f", 100.0 * t->mperf/t->tsc/tsc_tweak);
+               outp += sprintf(outp, "\t%.2f", 100.0 * t->mperf/tsc);
 
        if (DO_BIC(BIC_Bzy_MHz)) {
                if (has_base_hz)
                        outp += sprintf(outp, "\t%.0f", base_hz / units * t->aperf / t->mperf);
                else
                        outp += sprintf(outp, "\t%.0f",
-                               1.0 * t->tsc / units * t->aperf / t->mperf / interval_float);
+                               tsc / units * t->aperf / t->mperf / interval_float);
        }
 
        if (DO_BIC(BIC_TSC_MHz))
@@ -748,7 +750,7 @@ int format_counters(struct thread_data *t, struct core_data *c,
 
        /* C1 */
        if (DO_BIC(BIC_CPU_c1))
-               outp += sprintf(outp, "\t%.2f", 100.0 * t->c1/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * t->c1/tsc);
 
        /* Added counters */
        for (i = 0, mp = sys.tp; mp; i++, mp = mp->next) {
@@ -760,7 +762,7 @@ int format_counters(struct thread_data *t, struct core_data *c,
                } else if (mp->format == FORMAT_DELTA) {
                        outp += sprintf(outp, "\t%lld", t->counter[i]);
                } else if (mp->format == FORMAT_PERCENT) {
-                       outp += sprintf(outp, "\t%.2f", 100.0 * t->counter[i]/t->tsc);
+                       outp += sprintf(outp, "\t%.2f", 100.0 * t->counter[i]/tsc);
                }
        }
 
@@ -769,15 +771,15 @@ int format_counters(struct thread_data *t, struct core_data *c,
                goto done;
 
        if (DO_BIC(BIC_CPU_c3) && !do_slm_cstates && !do_knl_cstates)
-               outp += sprintf(outp, "\t%.2f", 100.0 * c->c3/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * c->c3/tsc);
        if (DO_BIC(BIC_CPU_c6))
-               outp += sprintf(outp, "\t%.2f", 100.0 * c->c6/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * c->c6/tsc);
        if (DO_BIC(BIC_CPU_c7))
-               outp += sprintf(outp, "\t%.2f", 100.0 * c->c7/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * c->c7/tsc);
 
        /* Mod%c6 */
        if (DO_BIC(BIC_Mod_c6))
-               outp += sprintf(outp, "\t%.2f", 100.0 * c->mc6_us / t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * c->mc6_us / tsc);
 
        if (DO_BIC(BIC_CoreTmp))
                outp += sprintf(outp, "\t%d", c->core_temp_c);
@@ -791,7 +793,7 @@ int format_counters(struct thread_data *t, struct core_data *c,
                } else if (mp->format == FORMAT_DELTA) {
                        outp += sprintf(outp, "\t%lld", c->counter[i]);
                } else if (mp->format == FORMAT_PERCENT) {
-                       outp += sprintf(outp, "\t%.2f", 100.0 * c->counter[i]/t->tsc);
+                       outp += sprintf(outp, "\t%.2f", 100.0 * c->counter[i]/tsc);
                }
        }
 
@@ -819,24 +821,24 @@ int format_counters(struct thread_data *t, struct core_data *c,
 
        /* Totl%C0, Any%C0 GFX%C0 CPUGFX% */
        if (do_skl_residency) {
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_wtd_core_c0/t->tsc);
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_any_core_c0/t->tsc);
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_any_gfxe_c0/t->tsc);
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_both_core_gfxe_c0/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_wtd_core_c0/tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_any_core_c0/tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_any_gfxe_c0/tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pkg_both_core_gfxe_c0/tsc);
        }
 
        if (do_pc2)
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc2/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc2/tsc);
        if (do_pc3)
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc3/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc3/tsc);
        if (do_pc6)
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc6/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc6/tsc);
        if (do_pc7)
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc7/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc7/tsc);
        if (do_c8_c9_c10) {
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc8/t->tsc);
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc9/t->tsc);
-               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc10/t->tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc8/tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc9/tsc);
+               outp += sprintf(outp, "\t%.2f", 100.0 * p->pc10/tsc);
        }
 
        /*
@@ -878,7 +880,7 @@ int format_counters(struct thread_data *t, struct core_data *c,
                } else if (mp->format == FORMAT_DELTA) {
                        outp += sprintf(outp, "\t%lld", p->counter[i]);
                } else if (mp->format == FORMAT_PERCENT) {
-                       outp += sprintf(outp, "\t%.2f", 100.0 * p->counter[i]/t->tsc);
+                       outp += sprintf(outp, "\t%.2f", 100.0 * p->counter[i]/tsc);
                }
        }
 
@@ -1048,7 +1050,7 @@ delta_thread(struct thread_data *new, struct thread_data *old,
                        old->c1 = 0;
                else {
                        /* normal case, derive c1 */
-                       old->c1 = old->tsc - old->mperf - core_delta->c3
+                       old->c1 = (old->tsc * tsc_tweak) - old->mperf - core_delta->c3
                                - core_delta->c6 - core_delta->c7;
                }
        }