diff mbox

[22/44] tools/power turbostat: use tsc_tweak everwhere it is needed

Message ID 008d396eb219ee5a1c98c9ef01c35752d35f0d6c.1488345270.git.len.brown@intel.com (mailing list archive)
State Mainlined
Delegated to: Rafael Wysocki
Headers show

Commit Message

Len Brown March 1, 2017, 5:27 a.m. UTC 
From: Len Brown <len.brown@intel.com>

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 | 48 ++++++++++++++++++-----------------
 1 file changed, 25 insertions(+), 23 deletions(-)
diff mbox

Patch

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 6867557596af..bbdf9ba9d41b 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -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;
 		}
 	}