]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
tools/power turbostat: Harden against unexpected values
authorLen Brown <len.brown@intel.com>
Mon, 8 Dec 2025 15:01:04 +0000 (10:01 -0500)
committerLen Brown <len.brown@intel.com>
Wed, 4 Feb 2026 20:52:11 +0000 (14:52 -0600)
Divide-by-zero resulted if LLC references == 0

Pull the percentage division into pct() to centralize sanity checks there.

Fixes: 8808292799b0 ("tools/power turbostat: Print "nan" for out of range percentages")
Signed-off-by: Len Brown <len.brown@intel.com>
tools/power/x86/turbostat/turbostat.c

index 97cd9c5a00929d133c230c2d4fe1591e5b900f19..4dd4b0f3e6d4d5dfa852cb745bb8fd683415388c 100644 (file)
@@ -3002,22 +3002,30 @@ void print_header(char *delim)
 }
 
 /*
- * pct()
+ * pct(numerator, denominator)
  *
- * If absolute value is < 1.1, return percentage
- * otherwise, return nan
+ * Return sanity checked percentage (100.0 * numerator/denominotor)
  *
- * return value is appropriate for printing percentages with %f
- * while flagging some obvious erroneous values.
+ * n < 0: nan
+ * d <= 0: nan
+ * n/d > 1.1: nan
  */
-double pct(double d)
+double pct(double numerator, double denominator)
 {
+       double retval;
 
-       double abs = fabs(d);
+       if (numerator < 0)
+               return nan("");
 
-       if (abs < 1.10)
-               return (100.0 * d);
-       return nan("");
+       if (denominator <= 0)
+               return nan("");
+
+       retval = 100.0 * numerator / denominator;
+
+       if (retval > 110.0)
+               return nan("");
+
+       return retval;
 }
 
 int dump_counters(PER_THREAD_PARAMS)
@@ -3047,7 +3055,7 @@ int dump_counters(PER_THREAD_PARAMS)
 
                outp += sprintf(outp, "LLC refs: %lld", t->llc.references);
                outp += sprintf(outp, "LLC miss: %lld", t->llc.misses);
-               outp += sprintf(outp, "LLC Hit%%: %.2f", pct((t->llc.references - t->llc.misses) / t->llc.references));
+               outp += sprintf(outp, "LLC Hit%%: %.2f", pct((t->llc.references - t->llc.misses), t->llc.references));
 
                for (i = 0, mp = sys.tp; mp; i++, mp = mp->next) {
                        outp += sprintf(outp, "tADDED [%d] %8s msr0x%x: %08llX %s\n", i, mp->name, mp->msr_num, t->counter[i], mp->sp->path);
@@ -3262,7 +3270,7 @@ int format_counters(PER_THREAD_PARAMS)
                outp += sprintf(outp, "%s%.0f", (printed++ ? delim : ""), 1.0 / units * t->aperf / interval_float);
 
        if (DO_BIC(BIC_Busy))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(t->mperf / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(t->mperf, tsc));
 
        if (DO_BIC(BIC_Bzy_MHz)) {
                if (has_base_hz)
@@ -3303,7 +3311,7 @@ int format_counters(PER_THREAD_PARAMS)
                        outp += sprintf(outp, "%s%.0f", (printed++ ? delim : ""), t->llc.references / interval_float / 1000);
 
                if (DO_BIC(BIC_LLC_HIT))
-                       outp += sprintf(outp, fmt8, (printed++ ? delim : ""), pct((t->llc.references - t->llc.misses) / t->llc.references));
+                       outp += sprintf(outp, fmt8, (printed++ ? delim : ""), pct((t->llc.references - t->llc.misses), t->llc.references));
        }
 
        /* Added Thread Counters */
@@ -3316,7 +3324,7 @@ int format_counters(PER_THREAD_PARAMS)
                        if (mp->type == COUNTER_USEC)
                                outp += print_float_value(&printed, delim, t->counter[i] / interval_float / 10000);
                        else
-                               outp += print_float_value(&printed, delim, pct(t->counter[i] / tsc));
+                               outp += print_float_value(&printed, delim, pct(t->counter[i], tsc));
                }
        }
 
@@ -3330,7 +3338,7 @@ int format_counters(PER_THREAD_PARAMS)
                        if (pp->type == COUNTER_USEC)
                                outp += print_float_value(&printed, delim, t->perf_counter[i] / interval_float / 10000);
                        else
-                               outp += print_float_value(&printed, delim, pct(t->perf_counter[i] / tsc));
+                               outp += print_float_value(&printed, delim, pct(t->perf_counter[i], tsc));
                }
        }
 
@@ -3344,34 +3352,34 @@ int format_counters(PER_THREAD_PARAMS)
                        break;
 
                case PMT_TYPE_XTAL_TIME:
-                       value_converted = pct(value_raw / crystal_hz / interval_float);
+                       value_converted = pct(value_raw / crystal_hz, interval_float);
                        outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), value_converted);
                        break;
 
                case PMT_TYPE_TCORE_CLOCK:
-                       value_converted = pct(value_raw / tcore_clock_freq_hz / interval_float);
+                       value_converted = pct(value_raw / tcore_clock_freq_hz, interval_float);
                        outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), value_converted);
                }
        }
 
        /* C1 */
        if (DO_BIC(BIC_CPU_c1))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(t->c1 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(t->c1, tsc));
 
        /* print per-core data only for 1st thread in core */
        if (!is_cpu_first_thread_in_core(t, c))
                goto done;
 
        if (DO_BIC(BIC_CPU_c3))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c3 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c3, tsc));
        if (DO_BIC(BIC_CPU_c6))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c6 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c6, tsc));
        if (DO_BIC(BIC_CPU_c7))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c7 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->c7, tsc));
 
        /* Mod%c6 */
        if (DO_BIC(BIC_Mod_c6))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->mc6_us / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(c->mc6_us, tsc));
 
        if (DO_BIC(BIC_CoreTmp))
                outp += sprintf(outp, "%s%d", (printed++ ? delim : ""), c->core_temp_c);
@@ -3387,7 +3395,7 @@ int format_counters(PER_THREAD_PARAMS)
                else if (mp->format == FORMAT_DELTA || mp->format == FORMAT_AVERAGE)
                        outp += print_decimal_value(mp->width, &printed, delim, c->counter[i]);
                else if (mp->format == FORMAT_PERCENT)
-                       outp += print_float_value(&printed, delim, pct(c->counter[i] / tsc));
+                       outp += print_float_value(&printed, delim, pct(c->counter[i], tsc));
        }
 
        /* Added perf Core counters */
@@ -3397,7 +3405,7 @@ int format_counters(PER_THREAD_PARAMS)
                else if (pp->format == FORMAT_DELTA || mp->format == FORMAT_AVERAGE)
                        outp += print_decimal_value(pp->width, &printed, delim, c->perf_counter[i]);
                else if (pp->format == FORMAT_PERCENT)
-                       outp += print_float_value(&printed, delim, pct(c->perf_counter[i] / tsc));
+                       outp += print_float_value(&printed, delim, pct(c->perf_counter[i], tsc));
        }
 
        /* Added PMT Core counters */
@@ -3410,12 +3418,12 @@ int format_counters(PER_THREAD_PARAMS)
                        break;
 
                case PMT_TYPE_XTAL_TIME:
-                       value_converted = pct(value_raw / crystal_hz / interval_float);
+                       value_converted = pct(value_raw / crystal_hz, interval_float);
                        outp += print_float_value(&printed, delim, value_converted);
                        break;
 
                case PMT_TYPE_TCORE_CLOCK:
-                       value_converted = pct(value_raw / tcore_clock_freq_hz / interval_float);
+                       value_converted = pct(value_raw / tcore_clock_freq_hz, interval_float);
                        outp += print_float_value(&printed, delim, value_converted);
                }
        }
@@ -3471,39 +3479,39 @@ int format_counters(PER_THREAD_PARAMS)
        if (DO_BIC(BIC_Totl_c0))
                outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), 100 * p->pkg_wtd_core_c0 / tsc);      /* can exceed 100% */
        if (DO_BIC(BIC_Any_c0))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_any_core_c0 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_any_core_c0, tsc));
        if (DO_BIC(BIC_GFX_c0))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_any_gfxe_c0 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_any_gfxe_c0, tsc));
        if (DO_BIC(BIC_CPUGFX))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_both_core_gfxe_c0 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pkg_both_core_gfxe_c0, tsc));
 
        if (DO_BIC(BIC_Pkgpc2))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc2 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc2, tsc));
        if (DO_BIC(BIC_Pkgpc3))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc3 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc3, tsc));
        if (DO_BIC(BIC_Pkgpc6))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc6 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc6, tsc));
        if (DO_BIC(BIC_Pkgpc7))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc7 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc7, tsc));
        if (DO_BIC(BIC_Pkgpc8))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc8 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc8, tsc));
        if (DO_BIC(BIC_Pkgpc9))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc9 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc9, tsc));
        if (DO_BIC(BIC_Pkgpc10))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc10 / tsc));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->pc10, tsc));
 
        if (DO_BIC(BIC_Diec6))
-               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->die_c6 / crystal_hz / interval_float));
+               outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->die_c6 / crystal_hz, interval_float));
 
        if (DO_BIC(BIC_CPU_LPI)) {
                if (p->cpu_lpi >= 0)
-                       outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->cpu_lpi / 1000000.0 / interval_float));
+                       outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->cpu_lpi / 1000000.0, interval_float));
                else
                        outp += sprintf(outp, "%s(neg)", (printed++ ? delim : ""));
        }
        if (DO_BIC(BIC_SYS_LPI)) {
                if (p->sys_lpi >= 0)
-                       outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->sys_lpi / 1000000.0 / interval_float));
+                       outp += sprintf(outp, "%s%.2f", (printed++ ? delim : ""), pct(p->sys_lpi / 1000000.0, interval_float));
                else
                        outp += sprintf(outp, "%s(neg)", (printed++ ? delim : ""));
        }
@@ -3543,7 +3551,7 @@ int format_counters(PER_THREAD_PARAMS)
                else if (mp->format == FORMAT_DELTA || mp->format == FORMAT_AVERAGE)
                        outp += print_decimal_value(mp->width, &printed, delim, p->counter[i]);
                else if (mp->format == FORMAT_PERCENT)
-                       outp += print_float_value(&printed, delim, pct(p->counter[i] / tsc));
+                       outp += print_float_value(&printed, delim, pct(p->counter[i], tsc));
        }
 
        /* Added perf Package Counters */
@@ -3555,7 +3563,7 @@ int format_counters(PER_THREAD_PARAMS)
                else if (pp->format == FORMAT_DELTA || mp->format == FORMAT_AVERAGE)
                        outp += print_decimal_value(pp->width, &printed, delim, p->perf_counter[i]);
                else if (pp->format == FORMAT_PERCENT)
-                       outp += print_float_value(&printed, delim, pct(p->perf_counter[i] / tsc));
+                       outp += print_float_value(&printed, delim, pct(p->perf_counter[i], tsc));
        }
 
        /* Added PMT Package Counters */
@@ -3568,12 +3576,12 @@ int format_counters(PER_THREAD_PARAMS)
                        break;
 
                case PMT_TYPE_XTAL_TIME:
-                       value_converted = pct(value_raw / crystal_hz / interval_float);
+                       value_converted = pct(value_raw / crystal_hz, interval_float);
                        outp += print_float_value(&printed, delim, value_converted);
                        break;
 
                case PMT_TYPE_TCORE_CLOCK:
-                       value_converted = pct(value_raw / tcore_clock_freq_hz / interval_float);
+                       value_converted = pct(value_raw / tcore_clock_freq_hz, interval_float);
                        outp += print_float_value(&printed, delim, value_converted);
                }
        }