From 9d31c676c6019df0c078950a0ddca87da4706b14 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Tue, 29 Apr 2014 15:33:06 -0700 Subject: powercap / RAPL: further relax energy counter checks Energy counters may roll slowly for some RAPL domains, checking all of them can be time consuming and takes unpredictable amount of time. Therefore, we relax the sanity check by only checking availability of the MSRs and non-zero value of the energy status counters. It has been shown sufficient for all the platforms tested to filter out inactive domains. Signed-off-by: Jacob Pan Acked-by: Durgadoss R Signed-off-by: Rafael J. Wysocki --- drivers/powercap/intel_rapl.c | 29 +++++++++-------------------- 1 file changed, 9 insertions(+), 20 deletions(-) (limited to 'drivers/powercap/intel_rapl.c') diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c index d9a0770b6c73..1c987d20c6b8 100644 --- a/drivers/powercap/intel_rapl.c +++ b/drivers/powercap/intel_rapl.c @@ -1124,8 +1124,7 @@ err_cleanup_package: static int rapl_check_domain(int cpu, int domain) { unsigned msr; - u64 val1, val2 = 0; - int retry = 0; + u64 val = 0; switch (domain) { case RAPL_DOMAIN_PACKAGE: @@ -1144,26 +1143,13 @@ static int rapl_check_domain(int cpu, int domain) pr_err("invalid domain id %d\n", domain); return -EINVAL; } - if (rdmsrl_safe_on_cpu(cpu, msr, &val1)) - return -ENODEV; - - /* PP1/uncore/graphics domain may not be active at the time of - * driver loading. So skip further checks. + /* make sure domain counters are available and contains non-zero + * values, otherwise skip it. */ - if (domain == RAPL_DOMAIN_PP1) - return 0; - /* energy counters roll slowly on some domains */ - while (++retry < 10) { - usleep_range(10000, 15000); - rdmsrl_safe_on_cpu(cpu, msr, &val2); - if ((val1 & ENERGY_STATUS_MASK) != (val2 & ENERGY_STATUS_MASK)) - return 0; - } - /* if energy counter does not change, report as bad domain */ - pr_info("domain %s energy ctr %llu:%llu not working, skip\n", - rapl_domain_names[domain], val1, val2); + if (rdmsrl_safe_on_cpu(cpu, msr, &val) || !val) + return -ENODEV; - return -ENODEV; + return 0; } /* Detect active and valid domains for the given CPU, caller must @@ -1180,6 +1166,9 @@ static int rapl_detect_domains(struct rapl_package *rp, int cpu) /* use physical package id to read counters */ if (!rapl_check_domain(cpu, i)) rp->domain_map |= 1 << i; + else + pr_warn("RAPL domain %s detection failed\n", + rapl_domain_names[i]); } rp->nr_domains = bitmap_weight(&rp->domain_map, RAPL_DOMAIN_MAX); if (!rp->nr_domains) { -- cgit v1.2.1