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powercap, intel_rapl, implement time window checks

PATCH RESEND In review Prarit Bhargava 2 participants 9 messages Mar 21, 2016 – Apr 11, 2016 Power management core

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#0 lore raw

v4 cover powercap, intel_rapl, implement time window checks

This was submitted back in December and not picked up after review.

P.

-----8<----
The Intel ASDM provides a maximum time window that can be specified when setting a time window in the RAPL driver. While the ASDM doesn't explicitly provide a minimum time window value, it does provide a minimum time window unit that also can be used as a minimum value.

This patchset implements barrier checking for the time windows, and adds reporting of a known bug in which the maxmimum time window value may be erroneously set to 0, as well as a module parameter to avoid the maximum window checks on broken BIOSes.

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>

Prarit Bhargava (3):
powercap, intel_rapl, implement get_max_time_window powercap, intel_rapl, implement check for minimum time window powercap, intel_rapl, Add ignore_max_time_window_check module
parameter for broken BIOSes

 drivers/powercap/intel_rapl.c   |   50 +++++++++++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 +++--
 2 files changed, 54 insertions(+), 2 deletions(-)
Signature · 1 line
1.7.9.3
author
#1 lore raw

PATCH v4 1/3 powercap, intel_rapl, implement get_max_time_window

The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 "Package RAPL Domain") provides a maximum time window which the system can support. This window is read-only and is currently not examined when setting the time windows for the package.

This patch implements get_max_time_window_us() and checks the window when a user attempts to set power capping for the package.

Before the patch it was possible to set the window to, for example, 10000 micro seconds:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us

/sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:9765

but from 'turbostat -d', the package is limited to 976us:

cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.)

(Note, there appears to be a rounding issue in turbostat which needs to also be fixed. Looking at the values in the register it is clear the value is 1/1024 = 976us.)

After the patch we are limited by the maximum time window:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us

-bash: echo: write error: Invalid argument /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>
---
 drivers/powercap/intel_rapl.c   |   31 +++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 ++++--
 2 files changed, 35 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +31 -0
index 6c592dc..feb063d 100644
@@ -493,13 +493,42 @@ static int get_current_power_limit(struct powercap_zone *power_zone, int id,
 	return ret;
 }
 
+static int get_max_time_window(struct powercap_zone *power_zone, int id,
+			       u64 *data)
+{
+	struct rapl_domain *rd;
+	int ret = 0;
+	u64 val;
+
+	get_online_cpus();
+	rd = power_zone_to_rapl_domain(power_zone);
+
+	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
+		ret = -EIO;
+	else
+		*data = val;
+
+	put_online_cpus();
+	return ret;
+}
+
 static int set_time_window(struct powercap_zone *power_zone, int id,
 								u64 window)
 {
 	struct rapl_domain *rd;
 	int ret = 0;
+	u64 max_window;
 
 	get_online_cpus();
+	ret = get_max_time_window(power_zone, id, &max_window);
+	if (ret < 0)
+		goto out;
+
+	if (window > max_window) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	rd = power_zone_to_rapl_domain(power_zone);
 	switch (rd->rpl[id].prim_id) {
 	case PL1_ENABLE:

@@ -511,6 +540,7 @@ static int set_time_window(struct powercap_zone *power_zone, int id,
 	default:
 		ret = -EINVAL;
 	}
+out:
 	put_online_cpus();
 	return ret;
 }

@@ -590,6 +620,7 @@ static const struct powercap_zone_constraint_ops constraint_ops = {
 	.set_time_window_us = set_time_window,
 	.get_time_window_us = get_time_window,
 	.get_max_power_uw = get_max_power,
+	.get_max_time_window_us = get_max_time_window,
 	.get_name = get_constraint_name,
 };
drivers/powercap/powercap_sys.c +4 -2
index 14bde0d..53fad0f 100644
@@ -101,7 +101,7 @@ static ssize_t store_constraint_##_attr(struct device *dev,\
 	int err; \
 	u64 value; \
 	struct powercap_zone *power_zone = to_powercap_zone(dev); \
-	int id; \
+	int id, ret; \
 	struct powercap_zone_constraint *pconst;\
 	\
 	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \

@@ -113,8 +113,10 @@ static ssize_t store_constraint_##_attr(struct device *dev,\
 	if (err) \
 		return -EINVAL; \
 	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
-		if (!pconst->ops->set_##_attr(power_zone, id, value)) \
+		ret = pconst->ops->set_##_attr(power_zone, id, value); \
+		if (!ret) \
 			return count; \
+		return ret; \
 	} \
 	\
 	return -ENODATA; \
Signature · 1 line
1.7.9.3
#2 lore raw

Re: [PATCH 1/3 v4] powercap, intel_rapl, implement get_max_time_window

Quoted 5 lines · Prarit Bhargava

The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 "Package RAPL Domain") provides a maximum time window which the system can support.  This window is read-only and is currently not examined when setting the time windows for the package.

Usually this field has lot of junk. It is not supported uniformly. The system provides this value from another ACPI element called PPCC. If supported this will be in

$ /sys/bus/pci/devices/0000:00:04.0/power_limits
$ grep . *
power_limit_0_max_uw:15000000
power_limit_0_min_uw:125000
power_limit_0_step_uw:1000000
power_limit_0_tmax_us:32000000
power_limit_0_tmin_us:28000000
power_limit_1_max_uw:25000000
power_limit_1_min_uw:25000000
power_limit_1_step_uw:1000000
power_limit_1_tmax_us:0
power_limit_1_tmin_us:0

Thanks,
Srinivas

Quoted 151 lines

This patch implements get_max_time_window_us() and checks the window when
a user attempts to set power capping for the package.

Before the patch it was possible to set the window to, for example, 10000
micro seconds:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:9765

but from 'turbostat -d', the package is limited to 976us:

cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.)

(Note, there appears to be a rounding issue in turbostat which needs to
also be fixed.  Looking at the values in the register it is clear the value is 1/1024 = 976us.)

After the patch we are limited by the maximum time window:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

-bash: echo: write error: Invalid argument
/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>

---
 drivers/powercap/intel_rapl.c   |   31
+++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 ++++--

 2 files changed, 35 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +0 -0
index 6c592dc..feb063d 100644
@@ -493,13 +493,42 @@ static int get_current_power_limit(struct
 powercap_zone *power_zone, int id,
  	return ret;
  }


+static int get_max_time_window(struct powercap_zone *power_zone, int id,

drivers/powercap/intel_rapl.c +18 -0
+			       u64 *data)
+{
+	struct rapl_domain *rd;
+	int ret = 0;
+	u64 val;
+
+	get_online_cpus();
+	rd = power_zone_to_rapl_domain(power_zone);
+
+	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
+		ret = -EIO;
+	else
+		*data = val;
+
+	put_online_cpus();
+	return ret;
+}
+

 static int set_time_window(struct powercap_zone *power_zone, int id, u64 window)
 {
  struct rapl_domain *rd;
  int ret = 0;

drivers/powercap/intel_rapl.c +1 -0
+	u64 max_window;


  get_online_cpus();

drivers/powercap/intel_rapl.c +9 -0
+	ret = get_max_time_window(power_zone, id, &max_window);
+	if (ret < 0)
+		goto out;
+
+	if (window > max_window) {
+		ret = -EINVAL;
+		goto out;
+	}
+

  rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) {
  case PL1_ENABLE:

drivers/powercap/intel_rapl.c +0 -0
@@ -511,6 +540,7 @@ static int set_time_window(struct powercap_zone
 *power_zone, int id,

  default:
  ret = -EINVAL;
  }
+out:
  put_online_cpus();
  return ret;
 }

drivers/powercap/intel_rapl.c +1 -0
@@ -590,6 +620,7 @@ static const struct powercap_zone_constraint_ops
 constraint_ops = {
  	.set_time_window_us = set_time_window,
  	.get_time_window_us = get_time_window,
  	.get_max_power_uw = get_max_power,
+	.get_max_time_window_us = get_max_time_window,
  	.get_name = get_constraint_name,
  };

drivers/powercap/powercap_sys.c +1 -1
index 14bde0d..53fad0f 100644
@@ -101,7 +101,7 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
  	int err; \
  	u64 value; \
  	struct powercap_zone *power_zone = to_powercap_zone(dev); \
-	int id; \
+	int id, ret; \
  	struct powercap_zone_constraint *pconst;\
  	\

  if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \

drivers/powercap/powercap_sys.c +3 -1
@@ -113,8 +113,10 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
  	if (err) \
  		return -EINVAL; \
  	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
-		if (!pconst->ops->set_##_attr(power_zone, id,
 value)) \
+		ret = pconst->ops->set_##_attr(power_zone, id,
 value); \
+		if (!ret) \
  			return count; \
+		return ret; \

  } \
  \
  return -ENODATA; \

author
#3 lore raw

Re: [PATCH 1/3 v4] powercap, intel_rapl, implement get_max_time_window

Quoted 10 lines · Srinivas
Quoted 5 lines · Prarit Bhargava

The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 "Package RAPL Domain") provides a maximum time window which the system can support. This window is read-only and is currently not examined when setting the time windows for the package.

Usually this field has lot of junk. It is not supported uniformly. The system provides this value from another ACPI element called PPCC. If supported this will be in

Quoted 13 lines
$ /sys/bus/pci/devices/0000:00:04.0/power_limits
$ grep . *
power_limit_0_max_uw:15000000
power_limit_0_min_uw:125000
power_limit_0_step_uw:1000000
power_limit_0_tmax_us:32000000
power_limit_0_tmin_us:28000000
power_limit_1_max_uw:25000000
power_limit_1_min_uw:25000000
power_limit_1_step_uw:1000000
power_limit_1_tmax_us:0
power_limit_1_tmin_us:0

Interesting. I'll go and take a look on my test system to see if this is supported.

P.

Quoted 153 lines

Thanks,
Srinivas

Quoted 151 lines

This patch implements get_max_time_window_us() and checks the window when
a user attempts to set power capping for the package.

Before the patch it was possible to set the window to, for example, 10000
micro seconds:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:9765

but from 'turbostat -d', the package is limited to 976us:

cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.)

(Note, there appears to be a rounding issue in turbostat which needs to
also be fixed. Looking at the values in the register it is clear the value is 1/1024 = 976us.)

After the patch we are limited by the maximum time window:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

-bash: echo: write error: Invalid argument
/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>
---
 drivers/powercap/intel_rapl.c   |   31
+++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 ++++--
 2 files changed, 35 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +29 -0
index 6c592dc..feb063d 100644
@@ -493,13 +493,42 @@ static int get_current_power_limit(struct
 powercap_zone *power_zone, int id,
 	return ret;
 }
 
+static int get_max_time_window(struct powercap_zone *power_zone, int
 id,
+			       u64 *data)
+{
+	struct rapl_domain *rd;
+	int ret = 0;
+	u64 val;
+
+	get_online_cpus();
+	rd = power_zone_to_rapl_domain(power_zone);
+
+	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
+		ret = -EIO;
+	else
+		*data = val;
+
+	put_online_cpus();
+	return ret;
+}
+
 static int set_time_window(struct powercap_zone *power_zone, int id,
 								u64
 window)
 {
 	struct rapl_domain *rd;
 	int ret = 0;
+	u64 max_window;
 
 	get_online_cpus();
+	ret = get_max_time_window(power_zone, id, &max_window);
+	if (ret < 0)
+		goto out;
+
+	if (window > max_window) {
+		ret = -EINVAL;
+		goto out;
+	}
+
drivers/powercap/intel_rapl.c +1 -0
 	rd = power_zone_to_rapl_domain(power_zone);
 	switch (rd->rpl[id].prim_id) {
 	case PL1_ENABLE:

@@ -511,6 +540,7 @@ static int set_time_window(struct powercap_zone
 *power_zone, int id,
 	default:
 		ret = -EINVAL;
 	}
+out:
 	put_online_cpus();
 	return ret;

}

drivers/powercap/intel_rapl.c +1 -0
@@ -590,6 +620,7 @@ static const struct powercap_zone_constraint_ops
 constraint_ops = {
 	.set_time_window_us = set_time_window,
 	.get_time_window_us = get_time_window,
 	.get_max_power_uw = get_max_power,
+	.get_max_time_window_us = get_max_time_window,
 	.get_name = get_constraint_name,
 };
drivers/powercap/powercap_sys.c +1 -1
index 14bde0d..53fad0f 100644
@@ -101,7 +101,7 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
 	int err; \
 	u64 value; \
 	struct powercap_zone *power_zone = to_powercap_zone(dev); \
-	int id; \
+	int id, ret; \
 	struct powercap_zone_constraint *pconst;\
 	\
drivers/powercap/powercap_sys.c +3 -1
 	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \

@@ -113,8 +113,10 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
 	if (err) \
 		return -EINVAL; \
 	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
-		if (!pconst->ops->set_##_attr(power_zone, id,
 value)) \
+		ret = pconst->ops->set_##_attr(power_zone, id,
 value); \
+		if (!ret) \
 			return count; \
+		return ret; \
drivers/powercap/powercap_sys.c +0 -0
 	} \
 	\
 	return -ENODATA; \
author
#4 lore raw

Re: [PATCH 1/3 v4] powercap, intel_rapl, implement get_max_time_window

In reply to Pandruvada, Srinivas
Quoted 10 lines · Srinivas
Quoted 5 lines · Prarit Bhargava

The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 "Package RAPL Domain") provides a maximum time window which the system can support. This window is read-only and is currently not examined when setting the time windows for the package.

Usually this field has lot of junk. It is not supported uniformly. The system provides this value from another ACPI element called PPCC. If supported this will be in

Quoted 13 lines
$ /sys/bus/pci/devices/0000:00:04.0/power_limits
$ grep . *
power_limit_0_max_uw:15000000
power_limit_0_min_uw:125000
power_limit_0_step_uw:1000000
power_limit_0_tmax_us:32000000
power_limit_0_tmin_us:28000000
power_limit_1_max_uw:25000000
power_limit_1_min_uw:25000000
power_limit_1_step_uw:1000000
power_limit_1_tmax_us:0
power_limit_1_tmin_us:0

Thanks Srinivas. Does this mean I should check for PPCC?

P.

Quoted 153 lines

Thanks,
Srinivas

Quoted 151 lines

This patch implements get_max_time_window_us() and checks the window when
a user attempts to set power capping for the package.

Before the patch it was possible to set the window to, for example, 10000
micro seconds:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:9765

but from 'turbostat -d', the package is limited to 976us:

cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.)

(Note, there appears to be a rounding issue in turbostat which needs to
also be fixed. Looking at the values in the register it is clear the value is 1/1024 = 976us.)

After the patch we are limited by the maximum time window:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

-bash: echo: write error: Invalid argument
/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>
---
 drivers/powercap/intel_rapl.c   |   31
+++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 ++++--
 2 files changed, 35 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +29 -0
index 6c592dc..feb063d 100644
@@ -493,13 +493,42 @@ static int get_current_power_limit(struct
 powercap_zone *power_zone, int id,
 	return ret;
 }
 
+static int get_max_time_window(struct powercap_zone *power_zone, int
 id,
+			       u64 *data)
+{
+	struct rapl_domain *rd;
+	int ret = 0;
+	u64 val;
+
+	get_online_cpus();
+	rd = power_zone_to_rapl_domain(power_zone);
+
+	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
+		ret = -EIO;
+	else
+		*data = val;
+
+	put_online_cpus();
+	return ret;
+}
+
 static int set_time_window(struct powercap_zone *power_zone, int id,
 								u64
 window)
 {
 	struct rapl_domain *rd;
 	int ret = 0;
+	u64 max_window;
 
 	get_online_cpus();
+	ret = get_max_time_window(power_zone, id, &max_window);
+	if (ret < 0)
+		goto out;
+
+	if (window > max_window) {
+		ret = -EINVAL;
+		goto out;
+	}
+
drivers/powercap/intel_rapl.c +1 -0
 	rd = power_zone_to_rapl_domain(power_zone);
 	switch (rd->rpl[id].prim_id) {
 	case PL1_ENABLE:

@@ -511,6 +540,7 @@ static int set_time_window(struct powercap_zone
 *power_zone, int id,
 	default:
 		ret = -EINVAL;
 	}
+out:
 	put_online_cpus();
 	return ret;

}

drivers/powercap/intel_rapl.c +1 -0
@@ -590,6 +620,7 @@ static const struct powercap_zone_constraint_ops
 constraint_ops = {
 	.set_time_window_us = set_time_window,
 	.get_time_window_us = get_time_window,
 	.get_max_power_uw = get_max_power,
+	.get_max_time_window_us = get_max_time_window,
 	.get_name = get_constraint_name,
 };
drivers/powercap/powercap_sys.c +1 -1
index 14bde0d..53fad0f 100644
@@ -101,7 +101,7 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
 	int err; \
 	u64 value; \
 	struct powercap_zone *power_zone = to_powercap_zone(dev); \
-	int id; \
+	int id, ret; \
 	struct powercap_zone_constraint *pconst;\
 	\
drivers/powercap/powercap_sys.c +3 -1
 	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \

@@ -113,8 +113,10 @@ static ssize_t store_constraint_##_attr(struct
 device *dev,\
 	if (err) \
 		return -EINVAL; \
 	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
-		if (!pconst->ops->set_##_attr(power_zone, id,
 value)) \
+		ret = pconst->ops->set_##_attr(power_zone, id,
 value); \
+		if (!ret) \
 			return count; \
+		return ret; \
drivers/powercap/powercap_sys.c +0 -0
 	} \
 	\
 	return -ENODATA; \
#5 lore raw

Re: [PATCH 1/3 v4] powercap, intel_rapl, implement get_max_time_window

Quoted 27 lines · Prarit Bhargava
Quoted 11 lines · Srinivas
Quoted 5 lines · Prarit Bhargava

The MSR_PKG_POWER_INFO register (Intel ASDM, section 14.9.3 "Package RAPL Domain") provides a maximum time window which the system can support.  This window is read-only and is currently not examined when setting the time windows for the package.

Usually this field has lot of junk. It is not supported uniformly. The system provides this value from another ACPI element called PPCC.
If supported this will be in

Quoted 13 lines
$ /sys/bus/pci/devices/0000:00:04.0/power_limits
$ grep . *
power_limit_0_max_uw:15000000
power_limit_0_min_uw:125000
power_limit_0_step_uw:1000000
power_limit_0_tmax_us:32000000
power_limit_0_tmin_us:28000000
power_limit_1_max_uw:25000000
power_limit_1_min_uw:25000000
power_limit_1_step_uw:1000000
power_limit_1_tmax_us:0
power_limit_1_tmin_us:0
Quoted 1 line

Thanks Srinivas.  Does this mean I should check for PPCC?

If your platform has support for this element.
Are you trying to solve specific problem or implement some feature using RAPL? May be we can help, what time window to set.

Thanks,
Srinivas

Quoted 170 lines

P.

Quoted 167 lines

Thanks,
Srinivas

Quoted 165 lines

This patch implements get_max_time_window_us() and checks the window
when
a user attempts to set power capping for the package.

Before the patch it was possible to set the window to, for example,
10000
micro seconds:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:9765

but from 'turbostat -d', the package is limited to 976us:

cpu0: MSR_PKG_POWER_INFO: 0x01200168 (45 W TDP, RAPL 36 - 0 W, 0.000977 sec.)

(Note, there appears to be a rounding issue in turbostat which needs
to
also be fixed.  Looking at the values in the register it is clear the
value is 1/1024 = 976us.)

After the patch we are limited by the maximum time window:

[root@intel-chiefriver-03 rhel7]# echo 10000 > /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us;
egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel- rapl\:0/constraint_0_time_window_us

-bash: echo: write error: Invalid argument
/sys/devices/virtual/powercap/intel-rapl/intel-
rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>

---
 drivers/powercap/intel_rapl.c   |   31
+++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 ++++--

 2 files changed, 35 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +0 -0
index 6c592dc..feb063d 100644
@@ -493,13 +493,42 @@ static int get_current_power_limit(struct
 powercap_zone *power_zone, int id,
  	return ret;
  }


+static int get_max_time_window(struct powercap_zone *power_zone, int
id,

drivers/powercap/intel_rapl.c +18 -0
+			       u64 *data)
+{
+	struct rapl_domain *rd;
+	int ret = 0;
+	u64 val;
+
+	get_online_cpus();
+	rd = power_zone_to_rapl_domain(power_zone);
+
+	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
+		ret = -EIO;
+	else
+		*data = val;
+
+	put_online_cpus();
+	return ret;
+}
+

 static int set_time_window(struct powercap_zone *power_zone, int id,

u64
window)
 {
  struct rapl_domain *rd;
  int ret = 0;

drivers/powercap/intel_rapl.c +1 -0
+	u64 max_window;


  get_online_cpus();

drivers/powercap/intel_rapl.c +9 -0
+	ret = get_max_time_window(power_zone, id, &max_window);
+	if (ret < 0)
+		goto out;
+
+	if (window > max_window) {
+		ret = -EINVAL;
+		goto out;
+	}
+

  rd = power_zone_to_rapl_domain(power_zone); switch (rd->rpl[id].prim_id) {
  case PL1_ENABLE:

drivers/powercap/intel_rapl.c +0 -0
@@ -511,6 +540,7 @@ static int set_time_window(struct

powercap_zone
*power_zone, int id,
  default:
  ret = -EINVAL;
  }
+out:
  put_online_cpus();
  return ret;
 }

drivers/powercap/intel_rapl.c +0 -0
@@ -590,6 +620,7 @@ static const struct

powercap_zone_constraint_ops
constraint_ops = {
  .set_time_window_us = set_time_window,
  .get_time_window_us = get_time_window,
  .get_max_power_uw = get_max_power,

drivers/powercap/intel_rapl.c +1 -0
+	.get_max_time_window_us = get_max_time_window,

  .get_name = get_constraint_name,
 };

drivers/powercap/powercap_sys.c +0 -0
index 14bde0d..53fad0f 100644
@@ -101,7 +101,7 @@ static ssize_t

store_constraint_##_attr(struct
device *dev,\
  int err; \
  u64 value; \
  struct powercap_zone *power_zone =
to_powercap_zone(dev); \

drivers/powercap/powercap_sys.c +1 -1
-	int id; \
+	int id, ret; \

  struct powercap_zone_constraint *pconst;\
  \
  if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \

drivers/powercap/powercap_sys.c +0 -0
@@ -113,8 +113,10 @@ static ssize_t

store_constraint_##_attr(struct
device *dev,\
  if (err) \
  return -EINVAL; \
  if (pconst && pconst->ops && pconst->ops->set_##_attr) { \

drivers/powercap/powercap_sys.c +0 -1
-		if (!pconst->ops->set_##_attr(power_zone, id,

value)) \

drivers/powercap/powercap_sys.c +1 -0
+		ret = pconst->ops->set_##_attr(power_zone, id,

value); \

drivers/powercap/powercap_sys.c +1 -0
+		if (!ret) \

  return count; \

drivers/powercap/powercap_sys.c +1 -0
+		return ret; \

  } \
  \
  return -ENODATA; \

author
#6 lore raw

PATCH v4 2/3 powercap, intel_rapl, implement check for minimum time window

In reply to Prarit Bhargava

Using an small value for the time window results in a bogus value for the time window. For example,

[root@intel-chiefriver-03 linux]# echo 950 > /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us -bash: echo: write error: Invalid argument /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:4501502475370496

The Intel ASDM doesn't explicitly define a minimum time window. The MSR_RAPL_POWER_UNIT register, read during initialization, does specify a minimum time window unit so that can be used as a lower bound for error checking.

After this change the minimum time window is properly clamped:

[root@intel-chiefriver-03 linux]# echo 950 > /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us; egrep ^ /sys/devices/virtual/powercap/intel-rapl/intel-rapl\:0/constraint_0_time_window_us -bash: echo: write error: Invalid argument /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_time_window_us:1:976

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>
---
 drivers/powercap/intel_rapl.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
drivers/powercap/intel_rapl.c +9 -2
index feb063d..cf89b3d 100644
@@ -516,6 +516,7 @@ static int set_time_window(struct powercap_zone *power_zone, int id,
 								u64 window)
 {
 	struct rapl_domain *rd;
+	struct rapl_package *rp;
 	int ret = 0;
 	u64 max_window;
 

@@ -524,12 +525,18 @@ static int set_time_window(struct powercap_zone *power_zone, int id,
 	if (ret < 0)
 		goto out;
 
-	if (window > max_window) {
+	rd = power_zone_to_rapl_domain(power_zone);
+	rp = find_package_by_id(rd->package_id);
+	/*
+	 * The Intel ASDM doesn't explicitly define a minimum time window.
+	 * The MSR_RAPL_POWER_UNIT register, read during initialization,
+	 * does contain the smallest unit of time that can be measured.
+	 */
+	if ((window > max_window) || (window < rp->time_unit)) {
 		ret = -EINVAL;
 		goto out;
 	}
 
-	rd = power_zone_to_rapl_domain(power_zone);
 	switch (rd->rpl[id].prim_id) {
 	case PL1_ENABLE:
 		rapl_write_data_raw(rd, TIME_WINDOW1, window);
Signature · 1 line
1.7.9.3
author
#7 lore raw

PATCH v3 3/3 powercap, intel_rapl, Add ignore_max_time_window_check module parameter for broken BIOSes

In reply to Prarit Bhargava

Some systems erroneously set the maximum time window field of MSR_PKG_POWER_INFO register to 0. This results in a user not being able to set the time windows for the package. In some cases, however, RAPL will still continue to work with a small window (albeit through some trial and error). This patch adds a ignore_max_time_window_check module parameter to avoid the maximum time window check in set_time_window().

[v2]: change name to max_time_window_check, fix (val == 0) check [v3]: fix typo in debug message

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>
---
 drivers/powercap/intel_rapl.c |   18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)
drivers/powercap/intel_rapl.c +15 -3
index cf89b3d..87dac13 100644
@@ -505,13 +505,24 @@ static int get_max_time_window(struct powercap_zone *power_zone, int id,
 
 	if (rapl_read_data_raw(rd, MAX_TIME_WINDOW, true, &val))
 		ret = -EIO;
-	else
+	else {
 		*data = val;
-
+		if (val == 0)
+			pr_warn_once(FW_BUG "intel_rapl: Maximum Time Window is zero.  This is a BIOS bug that should be reported to your hardware or BIOS vendor.  The value of zero may prevent Intel RAPL from functioning properly.  Most bugs can be avoided by setting the ignore_max_time_window_check module parameter.\n");
+	}
 	put_online_cpus();
 	return ret;
 }
 
+/* Some BIOSes incorrectly program the maximum time window in the
+ * MSR_PKG_POWER_INFO register.  Some of these systems still have functional
+ * RAPL registers, etc., so give the user the option of disabling the maximum
+ * time window check.
+ */
+static int ignore_max_time_window_check;
+module_param(ignore_max_time_window_check, int, 0444);
+MODULE_PARM_DESC(ignore_max_time_window_check, "Ignore maximum time window check.  A bug should be reported to your hardware or BIOS vendor if this parameter is used.");
+
 static int set_time_window(struct powercap_zone *power_zone, int id,
 								u64 window)
 {

@@ -532,7 +543,8 @@ static int set_time_window(struct powercap_zone *power_zone, int id,
 	 * The MSR_RAPL_POWER_UNIT register, read during initialization,
 	 * does contain the smallest unit of time that can be measured.
 	 */
-	if ((window > max_window) || (window < rp->time_unit)) {
+	if ((!ignore_max_time_window_check && (window > max_window)) ||
+	    (window < rp->time_unit)) {
 		ret = -EINVAL;
 		goto out;
 	}
Signature · 1 line
1.7.9.3
#8 lore raw
In reply to Prarit Bhargava

+Jacob

Quoted 40 lines · Prarit Bhargava

This was submitted back in December and not picked up after review.

P.

-----8<----
The Intel ASDM provides a maximum time window that can be specified when
setting a time window in the RAPL driver.  While the ASDM doesn't explicitly
provide a minimum time window value, it does provide a minimum time window
unit that also can be used as a minimum value.

This patchset implements barrier checking for the time windows, and adds
reporting of a known bug in which the maxmimum time window value may be
erroneously set to 0, as well as a module parameter to avoid the maximum
window checks on broken BIOSes.

Cc "Rafael J. Wysocki" <[email protected]>
Cc Prarit Bhargava <[email protected]>
Cc Radivoje Jovanovic <[email protected]>
Cc Seiichi Ikarashi <[email protected]>
Cc Mathias Krause <[email protected]>
Cc Ajay Thomas <[email protected]>
Signed-off-by Prarit Bhargava <[email protected]>

Prarit Bhargava (3):
  powercap, intel_rapl, implement get_max_time_window powercap, intel_rapl, implement check for minimum time window powercap, intel_rapl, Add ignore_max_time_window_check module parameter for broken BIOSes

 drivers/powercap/intel_rapl.c   |   50
+++++++++++++++++++++++++++++++++++++++
 drivers/powercap/powercap_sys.c |    6 +++--

 2 files changed, 54 insertions(+), 2 deletions(-)