From 9185e988e9d5bb70b690362e84bb2e4a9d71f2c5 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Wed, 6 Apr 2016 17:16:00 -0400 Subject: tools/power turbostat: work around RC6 counter wrap Sometimes the rc6 sysfs counter spontaneously resets, causing turbostat prints a very large number as it tries to calcuate % = 100 * (old - new) / interval When we see (old > new), print ***.**% instead of a bogus huge number. Note that this detection is not fool-proof, as the counter could reset several times and still result in new > old. Signed-off-by: Len Brown Signed-off-by: Rafael J. Wysocki --- tools/power/x86/turbostat/turbostat.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) (limited to 'tools/power') diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index 277e0321e590..d2ae87d148ed 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -189,7 +189,7 @@ struct pkg_data { unsigned long long pkg_any_core_c0; unsigned long long pkg_any_gfxe_c0; unsigned long long pkg_both_core_gfxe_c0; - unsigned long long gfx_rc6_ms; + long long gfx_rc6_ms; unsigned int gfx_mhz; unsigned int package_id; unsigned int energy_pkg; /* MSR_PKG_ENERGY_STATUS */ @@ -623,8 +623,14 @@ int format_counters(struct thread_data *t, struct core_data *c, outp += sprintf(outp, "%8d", p->pkg_temp_c); /* GFXrc6 */ - if (do_gfx_rc6_ms) - outp += sprintf(outp, "%8.2f", 100.0 * p->gfx_rc6_ms / 1000.0 / interval_float); + if (do_gfx_rc6_ms) { + if (p->gfx_rc6_ms == -1) { /* detect counter reset */ + outp += sprintf(outp, " ***.**"); + } else { + outp += sprintf(outp, "%8.2f", + p->gfx_rc6_ms / 10.0 / interval_float); + } + } /* GFXMHz */ if (do_gfx_mhz) @@ -768,7 +774,12 @@ delta_package(struct pkg_data *new, struct pkg_data *old) old->pc10 = new->pc10 - old->pc10; old->pkg_temp_c = new->pkg_temp_c; - old->gfx_rc6_ms = new->gfx_rc6_ms - old->gfx_rc6_ms; + /* flag an error when rc6 counter resets/wraps */ + if (old->gfx_rc6_ms > new->gfx_rc6_ms) + old->gfx_rc6_ms = -1; + else + old->gfx_rc6_ms = new->gfx_rc6_ms - old->gfx_rc6_ms; + old->gfx_mhz = new->gfx_mhz; DELTA_WRAP32(new->energy_pkg, old->energy_pkg); -- cgit v1.2.3