Re: [PATCH v2 2/2] thermal: Move therm_throt there from x86/mce

Srinivas Pandruvada
2021-01-25T17:18:41Z

Hi All,

On Mon, 2021-01-25 at 23:42 +0800, Zhang Rui wrote:
> Hi, Borislav,
>
> Thanks for the patch. CC Srinivas.
>
Thanks for adding me.

> On Mon, 2021-01-25 at 14:05 +0100, Borislav Petkov wrote:
> > From: Borislav Petkov <bp@suse.de>
> >
> > This functionality has nothing to do with MCE, move it to the
> > thermal(unfortunately)
> > framework and untangle it from MCE.
> >
Agreed.

But I have a question on how we should handle some new features.

Although interrupt handled in this code is called "Thermal interrupt",
this interrupt is also used for notification for some other power
/energy efficiency optimization events via IA32_THERM_STATUS and
IA32_PACKAGE_THERM_STATUS.

For example (From SDM):
IA32_PACKAGE_THERM_STATUS
Bit 26: Hardware Feedback Interface Structure Change Status

Can the handler, processing architectural features via thermal
interrupt, reside in arch/x86 folder or need to be
drivers/thermal/intel?

> Agreed.
>
> just one question,
> there are many overlaps between this kernel thermal throttling code
> and
> the x86_pkg_temp_thermal driver, is it possible to combine these two
> pieces of code altogether?
May not be a good idea as the events are not just for temperature
notifications.

Thanks,
Srinivas

>
> thanks,
> rui
>
>
> > Have thermal_set_handler() check the build-time assigned default
> > handler
> > stub was the one used before therm_throt assigns a new one.
> >
> > Requested-by: Peter Zijlstra <peterz@infradead.org>
> > Signed-off-by: Borislav Petkov <bp@suse.de>
> > ---
> > arch/x86/Kconfig | 4 ---
> > arch/x86/include/asm/irq.h | 4 +++
> > arch/x86/include/asm/mce.h | 16 ----------
> > arch/x86/include/asm/thermal.h | 21 ++++++++++++++
> > arch/x86/kernel/cpu/intel.c | 3 ++
> > arch/x86/kernel/cpu/mce/Makefile | 2 --
> > arch/x86/kernel/cpu/mce/intel.c | 1 -
> > arch/x86/kernel/irq.c | 29
> > +++++++++++++++++++
> > drivers/thermal/intel/Kconfig | 4 +++
> > drivers/thermal/intel/Makefile | 1 +
> > .../thermal/intel}/therm_throt.c | 25 ++-------------
> > -
> > drivers/thermal/intel/x86_pkg_temp_thermal.c | 3 +-
> > 12 files changed, 67 insertions(+), 46 deletions(-)
> > create mode 100644 arch/x86/include/asm/thermal.h
> > rename {arch/x86/kernel/cpu/mce =>
> > drivers/thermal/intel}/therm_throt.c (97%)
> >
> > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > index 21f851179ff0..9989db3a9bf5 100644
> > --- a/arch/x86/Kconfig
> > +++ b/arch/x86/Kconfig
> > @@ -1158,10 +1158,6 @@ config X86_MCE_INJECT
> > If you don't know what a machine check is and you don't do
> > kernel
> > QA it is safe to say n.
> >
> > -config X86_THERMAL_VECTOR
> > - def_bool y
> > - depends on X86_MCE_INTEL
> > -
> > source "arch/x86/events/Kconfig"
> >
> > config X86_LEGACY_VM86
> > diff --git a/arch/x86/include/asm/irq.h
> > b/arch/x86/include/asm/irq.h
> > index 528c8a71fe7f..ad65fe7dceb1 100644
> > --- a/arch/x86/include/asm/irq.h
> > +++ b/arch/x86/include/asm/irq.h
> > @@ -53,4 +53,8 @@ void arch_trigger_cpumask_backtrace(const struct
> > cpumask *mask,
> > #define arch_trigger_cpumask_backtrace
> > arch_trigger_cpumask_backtrace
> > #endif
> >
> > +#ifdef CONFIG_X86_THERMAL_VECTOR
> > +void thermal_set_handler(void (*handler)(void));
> > +#endif
> > +
> > #endif /* _ASM_X86_IRQ_H */
> > diff --git a/arch/x86/include/asm/mce.h
> > b/arch/x86/include/asm/mce.h
> > index def9aa5e1fa4..ddfb3cad8dff 100644
> > --- a/arch/x86/include/asm/mce.h
> > +++ b/arch/x86/include/asm/mce.h
> > @@ -288,22 +288,6 @@ extern void (*mce_threshold_vector)(void);
> > /* Deferred error interrupt handler */
> > extern void (*deferred_error_int_vector)(void);
> >
> > -/*
> > - * Thermal handler
> > - */
> > -
> > -void intel_init_thermal(struct cpuinfo_x86 *c);
> > -
> > -/* Interrupt Handler for core thermal thresholds */
> > -extern int (*platform_thermal_notify)(__u64 msr_val);
> > -
> > -/* Interrupt Handler for package thermal thresholds */
> > -extern int (*platform_thermal_package_notify)(__u64 msr_val);
> > -
> > -/* Callback support of rate control, return true, if
> > - * callback has rate control */
> > -extern bool (*platform_thermal_package_rate_control)(void);
> > -
> > /*
> > * Used by APEI to report memory error via /dev/mcelog
> > */
> > diff --git a/arch/x86/include/asm/thermal.h
> > b/arch/x86/include/asm/thermal.h
> > new file mode 100644
> > index 000000000000..58b0e0a4af6e
> > --- /dev/null
> > +++ b/arch/x86/include/asm/thermal.h
> > @@ -0,0 +1,21 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef _ASM_X86_THERMAL_H
> > +#define _ASM_X86_THERMAL_H
> > +
> > +/* Interrupt Handler for package thermal thresholds */
> > +extern int (*platform_thermal_package_notify)(__u64 msr_val);
> > +
> > +/* Interrupt Handler for core thermal thresholds */
> > +extern int (*platform_thermal_notify)(__u64 msr_val);
> > +
> > +/* Callback support of rate control, return true, if
> > + * callback has rate control */
> > +extern bool (*platform_thermal_package_rate_control)(void);
> > +
> > +#ifdef CONFIG_X86_THERMAL_VECTOR
> > +void intel_init_thermal(struct cpuinfo_x86 *c);
> > +#else
> > +static inline void intel_init_thermal(struct cpuinfo_x86 *c) { }
> > +#endif
> > +
> > +#endif /* _ASM_X86_THERMAL_H */
> > diff --git a/arch/x86/kernel/cpu/intel.c
> > b/arch/x86/kernel/cpu/intel.c
> > index 59a1e3ce3f14..71221af87cb1 100644
> > --- a/arch/x86/kernel/cpu/intel.c
> > +++ b/arch/x86/kernel/cpu/intel.c
> > @@ -24,6 +24,7 @@
> > #include <asm/traps.h>
> > #include <asm/resctrl.h>
> > #include <asm/numa.h>
> > +#include <asm/thermal.h>
> >
> > #ifdef CONFIG_X86_64
> > #include <linux/topology.h>
> > @@ -719,6 +720,8 @@ static void init_intel(struct cpuinfo_x86 *c)
> > tsx_disable();
> >
> > split_lock_init();
> > +
> > + intel_init_thermal(c);
> > }
> >
> > #ifdef CONFIG_X86_32
> > diff --git a/arch/x86/kernel/cpu/mce/Makefile
> > b/arch/x86/kernel/cpu/mce/Makefile
> > index 9f020c994154..015856abdbb1 100644
> > --- a/arch/x86/kernel/cpu/mce/Makefile
> > +++ b/arch/x86/kernel/cpu/mce/Makefile
> > @@ -9,8 +9,6 @@ obj-$(CONFIG_X86_MCE_THRESHOLD) += threshold.o
> > mce-inject-y := inject.o
> > obj-$(CONFIG_X86_MCE_INJECT) += mce-inject.o
> >
> > -obj-$(CONFIG_X86_THERMAL_VECTOR) += therm_throt.o
> > -
> > obj-$(CONFIG_ACPI_APEI) += apei.o
> >
> > obj-$(CONFIG_X86_MCELOG_LEGACY) += dev-mcelog.o
> > diff --git a/arch/x86/kernel/cpu/mce/intel.c
> > b/arch/x86/kernel/cpu/mce/intel.c
> > index c2476fe0682e..e309476743b7 100644
> > --- a/arch/x86/kernel/cpu/mce/intel.c
> > +++ b/arch/x86/kernel/cpu/mce/intel.c
> > @@ -531,7 +531,6 @@ static void intel_imc_init(struct cpuinfo_x86
> > *c)
> >
> > void mce_intel_feature_init(struct cpuinfo_x86 *c)
> > {
> > - intel_init_thermal(c);
> > intel_init_cmci();
> > intel_init_lmce();
> > intel_ppin_init(c);
> > diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
> > index c5dd50369e2f..523fa5266d3e 100644
> > --- a/arch/x86/kernel/irq.c
> > +++ b/arch/x86/kernel/irq.c
> > @@ -374,3 +374,32 @@ void fixup_irqs(void)
> > }
> > }
> > #endif
> > +
> > +#ifdef CONFIG_X86_THERMAL_VECTOR
> > +static void unexpected_thermal_interrupt(void)
> > +{
> > + pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
> > + smp_processor_id());
> > +}
> > +
> > +static void (*smp_thermal_vector)(void) =
> > unexpected_thermal_interrupt;
> > +
> > +void thermal_set_handler(void (*handler)(void))
> > +{
> > + if (handler) {
> > + WARN_ON(smp_thermal_vector !=
> > unexpected_thermal_interrupt);
> > + smp_thermal_vector = handler;
> > + } else {
> > + smp_thermal_vector = unexpected_thermal_interrupt;
> > + }
> > +}
> > +
> > +DEFINE_IDTENTRY_SYSVEC(sysvec_thermal)
> > +{
> > + trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
> > + inc_irq_stat(irq_thermal_count);
> > + smp_thermal_vector();
> > + trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
> > + ack_APIC_irq();
> > +}
> > +#endif
> > diff --git a/drivers/thermal/intel/Kconfig
> > b/drivers/thermal/intel/Kconfig
> > index 8025b21f43fa..ce4f59213c7a 100644
> > --- a/drivers/thermal/intel/Kconfig
> > +++ b/drivers/thermal/intel/Kconfig
> > @@ -8,6 +8,10 @@ config INTEL_POWERCLAMP
> > enforce idle time which results in more package C-state
> > residency. The
> > user interface is exposed via generic thermal framework.
> >
> > +config X86_THERMAL_VECTOR
> > + def_bool y
> > + depends on X86 && CPU_SUP_INTEL && X86_LOCAL_APIC
> > +
> > config X86_PKG_TEMP_THERMAL
> > tristate "X86 package temperature thermal driver"
> > depends on X86_THERMAL_VECTOR
> > diff --git a/drivers/thermal/intel/Makefile
> > b/drivers/thermal/intel/Makefile
> > index 0d9736ced5d4..ff2ad30ef397 100644
> > --- a/drivers/thermal/intel/Makefile
> > +++ b/drivers/thermal/intel/Makefile
> > @@ -10,3 +10,4 @@ obj-$(CONFIG_INTEL_QUARK_DTS_THERMAL) +=
> > intel_quark_dts_thermal.o
> > obj-$(CONFIG_INT340X_THERMAL) += int340x_thermal/
> > obj-$(CONFIG_INTEL_BXT_PMIC_THERMAL) += intel_bxt_pmic_thermal.o
> > obj-$(CONFIG_INTEL_PCH_THERMAL) += intel_pch_thermal.o
> > +obj-$(CONFIG_X86_THERMAL_VECTOR) += therm_throt.o
> > diff --git a/arch/x86/kernel/cpu/mce/therm_throt.c
> > b/drivers/thermal/intel/therm_throt.c
> > similarity index 97%
> > rename from arch/x86/kernel/cpu/mce/therm_throt.c
> > rename to drivers/thermal/intel/therm_throt.c
> > index 5b1aa0f30655..4f12fcd0e40a 100644
> > --- a/arch/x86/kernel/cpu/mce/therm_throt.c
> > +++ b/drivers/thermal/intel/therm_throt.c
> > @@ -26,13 +26,11 @@
> > #include <linux/cpu.h>
> >
> > #include <asm/processor.h>
> > +#include <asm/thermal.h>
> > #include <asm/traps.h>
> > #include <asm/apic.h>
> > -#include <asm/mce.h>
> > +#include <asm/irq.h>
> > #include <asm/msr.h>
> > -#include <asm/trace/irq_vectors.h>
> > -
> > -#include "internal.h"
> >
> > /* How long to wait between reporting thermal events */
> > #define CHECK_INTERVAL (300 * HZ)
> > @@ -606,23 +604,6 @@ static void intel_thermal_interrupt(void)
> > }
> > }
> >
> > -static void unexpected_thermal_interrupt(void)
> > -{
> > - pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
> > - smp_processor_id());
> > -}
> > -
> > -static void (*smp_thermal_vector)(void) =
> > unexpected_thermal_interrupt;
> > -
> > -DEFINE_IDTENTRY_SYSVEC(sysvec_thermal)
> > -{
> > - trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
> > - inc_irq_stat(irq_thermal_count);
> > - smp_thermal_vector();
> > - trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
> > - ack_APIC_irq();
> > -}
> > -
> > /* Thermal monitoring depends on APIC, ACPI and clock modulation
> > */
> > static int intel_thermal_supported(struct cpuinfo_x86 *c)
> > {
> > @@ -718,7 +699,7 @@ void intel_init_thermal(struct cpuinfo_x86 *c)
> > | PACKAGE_THERM_INT_HIGH_ENABLE), h);
> > }
> >
> > - smp_thermal_vector = intel_thermal_interrupt;
> > + thermal_set_handler(intel_thermal_interrupt);
> >
> > rdmsr(MSR_IA32_MISC_ENABLE, l, h);
> > wrmsr(MSR_IA32_MISC_ENABLE, l | MSR_IA32_MISC_ENABLE_TM1, h);
> > diff --git a/drivers/thermal/intel/x86_pkg_temp_thermal.c
> > b/drivers/thermal/intel/x86_pkg_temp_thermal.c
> > index b81c33202f41..090f9176ba62 100644
> > --- a/drivers/thermal/intel/x86_pkg_temp_thermal.c
> > +++ b/drivers/thermal/intel/x86_pkg_temp_thermal.c
> > @@ -17,8 +17,9 @@
> > #include <linux/pm.h>
> > #include <linux/thermal.h>
> > #include <linux/debugfs.h>
> > +
> > #include <asm/cpu_device_id.h>
> > -#include <asm/mce.h>
> > +#include <asm/thermal.h>
> >
> > /*
> > * Rate control delay: Idea is to introduce denounce effect