[Xenial,1/1] thermal/powerclamp: remove cpu whitelist

Message ID 20170407142127.5239-1-kai.heng.feng@canonical.com
State New
Headers show

Commit Message

Kai Heng Feng April 7, 2017, 2:21 p.m.
From: Jacob Pan <jacob.jun.pan@linux.intel.com>

BugLink: https://bugs.launchpad.net/bugs/1591641

Powerclamp works by aligning idle time to achieve package level
idle states, aka cstates. As long as one of the package cstates
is available, synchronized idle injection is meaningful.

This patch replaces the CPU whitelist with CPU feature and
package cstate counter check such that we don't have to modify
this whitelist for every new CPU.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
(cherry picked from commit b721ca0d192754deccb89fb01c77e41e6fd91ad9)
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
 drivers/thermal/intel_powerclamp.c | 47 ++++++++------------------------------
 1 file changed, 9 insertions(+), 38 deletions(-)

Comments

Seth Forshee April 10, 2017, 3:43 p.m. | #1
On Fri, Apr 07, 2017 at 03:21:27PM +0100, Kai-Heng Feng wrote:
> From: Jacob Pan <jacob.jun.pan@linux.intel.com>
> 
> BugLink: https://bugs.launchpad.net/bugs/1591641
> 
> Powerclamp works by aligning idle time to achieve package level
> idle states, aka cstates. As long as one of the package cstates
> is available, synchronized idle injection is meaningful.
> 
> This patch replaces the CPU whitelist with CPU feature and
> package cstate counter check such that we don't have to modify
> this whitelist for every new CPU.
> 
> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> (cherry picked from commit b721ca0d192754deccb89fb01c77e41e6fd91ad9)
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

It looks to me like there are some follow-up commits needed, one to fix
a bug in this patch (loading powerclamp on cpus which don't support it)
and another to fix a bug introduced by the previous fix.

3105f234e0ab thermal/powerclamp: correct cpu support check
ec638db8cb9d thermal/powerclamp: add back module device table

Thanks,
Seth
Kai Heng Feng April 12, 2017, 5:11 a.m. | #2
On Mon, Apr 10, 2017 at 11:43 PM Seth Forshee <seth.forshee@canonical.com>
wrote:

>
> It looks to me like there are some follow-up commits needed, one to fix
> a bug in this patch (loading powerclamp on cpus which don't support it)
> and another to fix a bug introduced by the previous fix.
>

> 3105f234e0ab thermal/powerclamp: correct cpu support check
> ec638db8cb9d thermal/powerclamp: add back module device table
>

You are right, I'll resend patches after test these commits on a real
machine.


>
> Thanks,
> Seth
>

Patch

diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index 6c79588251d5..015ce2eb6eb7 100644
--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -510,12 +510,6 @@  static int start_power_clamp(void)
 	unsigned long cpu;
 	struct task_struct *thread;
 
-	/* check if pkg cstate counter is completely 0, abort in this case */
-	if (!has_pkg_state_counter()) {
-		pr_err("pkg cstate counter not functional, abort\n");
-		return -EINVAL;
-	}
-
 	set_target_ratio = clamp(set_target_ratio, 0U, MAX_TARGET_RATIO - 1);
 	/* prevent cpu hotplug */
 	get_online_cpus();
@@ -672,35 +666,11 @@  static struct thermal_cooling_device_ops powerclamp_cooling_ops = {
 	.set_cur_state = powerclamp_set_cur_state,
 };
 
-/* runs on Nehalem and later */
 static const struct x86_cpu_id intel_powerclamp_ids[] __initconst = {
-	{ X86_VENDOR_INTEL, 6, 0x1a},
-	{ X86_VENDOR_INTEL, 6, 0x1c},
-	{ X86_VENDOR_INTEL, 6, 0x1e},
-	{ X86_VENDOR_INTEL, 6, 0x1f},
-	{ X86_VENDOR_INTEL, 6, 0x25},
-	{ X86_VENDOR_INTEL, 6, 0x26},
-	{ X86_VENDOR_INTEL, 6, 0x2a},
-	{ X86_VENDOR_INTEL, 6, 0x2c},
-	{ X86_VENDOR_INTEL, 6, 0x2d},
-	{ X86_VENDOR_INTEL, 6, 0x2e},
-	{ X86_VENDOR_INTEL, 6, 0x2f},
-	{ X86_VENDOR_INTEL, 6, 0x37},
-	{ X86_VENDOR_INTEL, 6, 0x3a},
-	{ X86_VENDOR_INTEL, 6, 0x3c},
-	{ X86_VENDOR_INTEL, 6, 0x3d},
-	{ X86_VENDOR_INTEL, 6, 0x3e},
-	{ X86_VENDOR_INTEL, 6, 0x3f},
-	{ X86_VENDOR_INTEL, 6, 0x45},
-	{ X86_VENDOR_INTEL, 6, 0x46},
-	{ X86_VENDOR_INTEL, 6, 0x47},
-	{ X86_VENDOR_INTEL, 6, 0x4c},
-	{ X86_VENDOR_INTEL, 6, 0x4d},
-	{ X86_VENDOR_INTEL, 6, 0x4e},
-	{ X86_VENDOR_INTEL, 6, 0x4f},
-	{ X86_VENDOR_INTEL, 6, 0x56},
-	{ X86_VENDOR_INTEL, 6, 0x57},
-	{ X86_VENDOR_INTEL, 6, 0x5e},
+	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_MWAIT },
+	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_ARAT },
+	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_NONSTOP_TSC },
+	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, X86_FEATURE_CONSTANT_TSC},
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, intel_powerclamp_ids);
@@ -712,11 +682,12 @@  static int __init powerclamp_probe(void)
 				boot_cpu_data.x86, boot_cpu_data.x86_model);
 		return -ENODEV;
 	}
-	if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC) ||
-		!boot_cpu_has(X86_FEATURE_CONSTANT_TSC) ||
-		!boot_cpu_has(X86_FEATURE_MWAIT) ||
-		!boot_cpu_has(X86_FEATURE_ARAT))
+
+	/* The goal for idle time alignment is to achieve package cstate. */
+	if (!has_pkg_state_counter()) {
+		pr_info("No package C-state available");
 		return -ENODEV;
+	}
 
 	/* find the deepest mwait value */
 	find_target_mwait();