Commit 75c7003f authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar

perf/x86/intel/rapl: Calculate timing once

No point in doing the same calculation over and over. Do it once in
rapl_check_hw_unit().
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221012.409238136@linutronix.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent b8b3319a
...@@ -129,6 +129,7 @@ static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly; /* 1/2^hw_unit Joule */ ...@@ -129,6 +129,7 @@ static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly; /* 1/2^hw_unit Joule */
static struct pmu rapl_pmu_class; static struct pmu rapl_pmu_class;
static cpumask_t rapl_cpu_mask; static cpumask_t rapl_cpu_mask;
static int rapl_cntr_mask; static int rapl_cntr_mask;
static u64 rapl_timer_ms;
static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu); static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu);
static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu_to_free); static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu_to_free);
...@@ -558,7 +559,6 @@ static int rapl_cpu_prepare(int cpu) ...@@ -558,7 +559,6 @@ static int rapl_cpu_prepare(int cpu)
{ {
struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu); struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
int phys_id = topology_physical_package_id(cpu); int phys_id = topology_physical_package_id(cpu);
u64 ms;
if (pmu) if (pmu)
return 0; return 0;
...@@ -575,19 +575,7 @@ static int rapl_cpu_prepare(int cpu) ...@@ -575,19 +575,7 @@ static int rapl_cpu_prepare(int cpu)
pmu->pmu = &rapl_pmu_class; pmu->pmu = &rapl_pmu_class;
/* pmu->timer_interval = ms_to_ktime(rapl_timer_ms);
* use reference of 200W for scaling the timeout
* to avoid missing counter overflows.
* 200W = 200 Joules/sec
* divide interval by 2 to avoid lockstep (2 * 100)
* if hw unit is 32, then we use 2 ms 1/200/2
*/
if (rapl_hw_unit[0] < 32)
ms = (1000 / (2 * 100)) * (1ULL << (32 - rapl_hw_unit[0] - 1));
else
ms = 2;
pmu->timer_interval = ms_to_ktime(ms);
rapl_hrtimer_init(pmu); rapl_hrtimer_init(pmu);
...@@ -676,6 +664,19 @@ static int rapl_check_hw_unit(void (*quirk)(void)) ...@@ -676,6 +664,19 @@ static int rapl_check_hw_unit(void (*quirk)(void))
/* Apply cpu model quirk */ /* Apply cpu model quirk */
if (quirk) if (quirk)
quirk(); quirk();
/*
* Calculate the timer rate:
* Use reference of 200W for scaling the timeout to avoid counter
* overflows. 200W = 200 Joules/sec
* Divide interval by 2 to avoid lockstep (2 * 100)
* if hw unit is 32, then we use 2 ms 1/200/2
*/
rapl_timer_ms = 2;
if (rapl_hw_unit[0] < 32) {
rapl_timer_ms = (1000 / (2 * 100));
rapl_timer_ms *= (1ULL << (32 - rapl_hw_unit[0] - 1));
}
return 0; return 0;
} }
...@@ -695,9 +696,7 @@ static const struct x86_cpu_id rapl_cpu_match[] = { ...@@ -695,9 +696,7 @@ static const struct x86_cpu_id rapl_cpu_match[] = {
static int __init rapl_pmu_init(void) static int __init rapl_pmu_init(void)
{ {
void (*quirk)(void) = NULL; void (*quirk)(void) = NULL;
struct rapl_pmu *pmu; int cpu, ret, i;
int cpu, ret;
int i;
/* /*
* check for Intel processor family 6 * check for Intel processor family 6
...@@ -758,15 +757,14 @@ static int __init rapl_pmu_init(void) ...@@ -758,15 +757,14 @@ static int __init rapl_pmu_init(void)
} }
__perf_cpu_notifier(rapl_cpu_notifier); __perf_cpu_notifier(rapl_cpu_notifier);
cpu_notifier_register_done();
pmu = __this_cpu_read(rapl_pmu);
pr_info("RAPL PMU detected," pr_info("RAPL PMU detected,"
" API unit is 2^-32 Joules," " API unit is 2^-32 Joules,"
" %d fixed counters" " %d fixed counters"
" %llu ms ovfl timer\n", " %llu ms ovfl timer\n",
hweight32(rapl_cntr_mask), hweight32(rapl_cntr_mask),
ktime_to_ms(pmu->timer_interval)); rapl_timer_ms);
for (i = 0; i < NR_RAPL_DOMAINS; i++) { for (i = 0; i < NR_RAPL_DOMAINS; i++) {
if (rapl_cntr_mask & (1 << i)) { if (rapl_cntr_mask & (1 << i)) {
pr_info("hw unit of domain %s 2^-%d Joules\n", pr_info("hw unit of domain %s 2^-%d Joules\n",
...@@ -774,7 +772,6 @@ static int __init rapl_pmu_init(void) ...@@ -774,7 +772,6 @@ static int __init rapl_pmu_init(void)
} }
} }
cpu_notifier_register_done();
return 0; return 0;
out: out:
......
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