Re: [PATCH] powercap/rapl: handle domain energy unit

[Jacob Pan]

On Wed, 11 Mar 2015 23:01:30 +0100
"Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> wrote:

> On Wednesday, March 11, 2015 05:55:09 AM Jacob Pan wrote:
> > The current driver assumes all RAPL domains within a CPU package
> > have the same energy unit. This is no longer true for HSW server
> > CPUs since DRAM domain has is own fixed energy unit which can be
> > different than the package energy unit enumerated by package
> > power MSR. In fact, the default HSW EP package power unit is 61uJ
> > whereas DRAM domain unit is 15.3uJ. The result is that DRAM power
> > consumption is counted 4x more than real power reported by energy
> > counters.
> > 
> > This patch adds domain specific energy unit per cpu type, it allows
> > domain energy unit to override package energy unit if non zero.
> > 
> > Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> 
> Should I regard this as a fix for 4.0?  If so, should it also go to
> "stable" (and which "stable" series should it go to in that case)?
> 
yes, it is a bug fix. I think this should be applied to all stable
kernels since RAPL driver was merged. So 3.10.71 and later.

> > ---
> >  drivers/powercap/intel_rapl.c | 35
> > ++++++++++++++++++++++++++++------- 1 file changed, 28
> > insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/powercap/intel_rapl.c
> > b/drivers/powercap/intel_rapl.c index 97b5e4e..af4c61e 100644
> > --- a/drivers/powercap/intel_rapl.c
> > +++ b/drivers/powercap/intel_rapl.c
> > @@ -158,6 +158,7 @@ struct rapl_domain {
> >  	struct rapl_power_limit rpl[NR_POWER_LIMITS];
> >  	u64 attr_map; /* track capabilities */
> >  	unsigned int state;
> > +	unsigned int domain_energy_unit;
> >  	int package_id;
> >  };
> >  #define power_zone_to_rapl_domain(_zone) \
> > @@ -190,6 +191,7 @@ struct rapl_defaults {
> >  	void (*set_floor_freq)(struct rapl_domain *rd, bool mode);
> >  	u64 (*compute_time_window)(struct rapl_package *rp, u64
> > val, bool to_raw);
> > +	unsigned int dram_domain_energy_unit;
> >  };
> >  static struct rapl_defaults *rapl_defaults;
> >  
> > @@ -227,7 +229,8 @@ static int rapl_read_data_raw(struct
> > rapl_domain *rd, static int rapl_write_data_raw(struct rapl_domain
> > *rd, enum rapl_primitives prim,
> >  			unsigned long long value);
> > -static u64 rapl_unit_xlate(int package, enum unit_type type, u64
> > value, +static u64 rapl_unit_xlate(struct rapl_domain *rd, int
> > package,
> > +			enum unit_type type, u64 value,
> >  			int to_raw);
> >  static void package_power_limit_irq_save(int package_id);
> >  
> > @@ -305,7 +308,8 @@ static int get_energy_counter(struct
> > powercap_zone *power_zone, u64 *energy_raw) 
> >  static int get_max_energy_counter(struct powercap_zone *pcd_dev,
> > u64 *energy) {
> > -	*energy = rapl_unit_xlate(0, ENERGY_UNIT,
> > ENERGY_STATUS_MASK, 0);
> > +	/* package domain is the largest */
> > +	*energy = rapl_unit_xlate(NULL, 0, ENERGY_UNIT,
> > ENERGY_STATUS_MASK, 0); return 0;
> >  }
> >  
> > @@ -639,6 +643,11 @@ static void rapl_init_domains(struct
> > rapl_package *rp) rd->msrs[4] = MSR_DRAM_POWER_INFO;
> >  			rd->rpl[0].prim_id = PL1_ENABLE;
> >  			rd->rpl[0].name = pl1_name;
> > +			rd->domain_energy_unit =
> > +
> > rapl_defaults->dram_domain_energy_unit;
> > +			if (rd->domain_energy_unit)
> > +				pr_info("DRAM domain energy unit
> > %duj\n",
> > +					rd->domain_energy_unit);
> >  			break;
> >  		}
> >  		if (mask) {
> > @@ -648,7 +657,8 @@ static void rapl_init_domains(struct
> > rapl_package *rp) }
> >  }
> >  
> > -static u64 rapl_unit_xlate(int package, enum unit_type type, u64
> > value, +static u64 rapl_unit_xlate(struct rapl_domain *rd, int
> > package,
> > +			enum unit_type type, u64 value,
> >  			int to_raw)
> >  {
> >  	u64 units = 1;
> > @@ -663,7 +673,11 @@ static u64 rapl_unit_xlate(int package, enum
> > unit_type type, u64 value, units = rp->power_unit;
> >  		break;
> >  	case ENERGY_UNIT:
> > -		units = rp->energy_unit;
> > +		/* per domain unit takes precedence */
> > +		if (rd && rd->domain_energy_unit)
> > +			units = rd->domain_energy_unit;
> > +		else
> > +			units = rp->energy_unit;
> >  		break;
> >  	case TIME_UNIT:
> >  		return rapl_defaults->compute_time_window(rp,
> > value, to_raw); @@ -773,7 +787,7 @@ static int
> > rapl_read_data_raw(struct rapl_domain *rd, final = value & rp->mask;
> >  	final = final >> rp->shift;
> >  	if (xlate)
> > -		*data = rapl_unit_xlate(rd->package_id, rp->unit,
> > final, 0);
> > +		*data = rapl_unit_xlate(rd, rd->package_id,
> > rp->unit, final, 0); else
> >  		*data = final;
> >  
> > @@ -799,7 +813,7 @@ static int rapl_write_data_raw(struct
> > rapl_domain *rd, "failed to read msr 0x%x on cpu %d\n", msr, cpu);
> >  		return -EIO;
> >  	}
> > -	value = rapl_unit_xlate(rd->package_id, rp->unit, value,
> > 1);
> > +	value = rapl_unit_xlate(rd, rd->package_id, rp->unit,
> > value, 1); msr_val &= ~rp->mask;
> >  	msr_val |= value << rp->shift;
> >  	if (wrmsrl_safe_on_cpu(cpu, msr, msr_val)) {
> > @@ -1017,6 +1031,13 @@ static const struct rapl_defaults
> > rapl_defaults_core = { .compute_time_window =
> > rapl_compute_time_window_core, };
> >  
> > +static const struct rapl_defaults rapl_defaults_hsw_server = {
> > +	.check_unit = rapl_check_unit_core,
> > +	.set_floor_freq = set_floor_freq_default,
> > +	.compute_time_window = rapl_compute_time_window_core,
> > +	.dram_domain_energy_unit = 15,
> > +};
> > +
> >  static const struct rapl_defaults rapl_defaults_atom = {
> >  	.check_unit = rapl_check_unit_atom,
> >  	.set_floor_freq = set_floor_freq_atom,
> > @@ -1037,7 +1058,7 @@ static const struct x86_cpu_id rapl_ids[] = {
> >  	RAPL_CPU(0x3a, rapl_defaults_core),/* Ivy Bridge */
> >  	RAPL_CPU(0x3c, rapl_defaults_core),/* Haswell */
> >  	RAPL_CPU(0x3d, rapl_defaults_core),/* Broadwell */
> > -	RAPL_CPU(0x3f, rapl_defaults_core),/* Haswell */
> > +	RAPL_CPU(0x3f, rapl_defaults_hsw_server),/* Haswell
> > servers */ RAPL_CPU(0x45, rapl_defaults_core),/* Haswell ULT */
> >  	RAPL_CPU(0x4C, rapl_defaults_atom),/* Braswell */
> >  	RAPL_CPU(0x4A, rapl_defaults_atom),/* Tangier */
> > 
> 

[Jacob Pan]
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