[PATCH v7 13/14] x86/resctrl: Simplify Kconfig options for resctrl

[Tony Luck]

Linus Torvalds complained[1] about Kconfig complexity making it too
hard for "random people to build their own kernels".

CONFIG_X86_CPU_RESCTRL_INTEL_AET has been causing problems since
it was first added as it unnaturally required other config options
to be set to "built-in".

AET now resolves PMT symbols at runtime via the registration API,
so INTEL_PMT_TELEMETRY no longer needs to be built-in. This means
that AET can be included unconditionally as part of X86_CPU_RESCTRL.

CONFIG_X86_CPU_RESCTRL now depends on X86_64 because reading telemetry
data needs readq().

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Link: https://lore.kernel.org/all/CAHk-=whigg3hvOy7c1j1MXFy6o6CHp0g4Tc3Y-MAk+XDssHU0A@xxxxxxxxxxxxxx # 1
---
 arch/x86/include/asm/resctrl.h         |  7 -------
 arch/x86/kernel/cpu/resctrl/internal.h | 13 -------------
 arch/x86/Kconfig                       | 15 +--------------
 arch/x86/kernel/cpu/resctrl/Makefile   |  2 +-
 4 files changed, 2 insertions(+), 35 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index c23d9c56a337..5a61d0b0955d 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -195,17 +195,10 @@ static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r,
 
 void resctrl_cpu_detect(struct cpuinfo_x86 *c);
 
-#ifdef CONFIG_X86_CPU_RESCTRL_INTEL_AET
 void intel_aet_register_enumeration(struct module *module,
 				    struct pmt_feature_group *(*get)(enum pmt_feature_id id),
 				    void (*put)(struct pmt_feature_group *p));
 void intel_aet_unregister_enumeration(void);
-#else
-static inline void intel_aet_register_enumeration(struct module *module,
-						  struct pmt_feature_group *(*get)(enum pmt_feature_id id),
-						  void (*put)(struct pmt_feature_group *p)) { }
-static inline void intel_aet_unregister_enumeration(void) { }
-#endif /* CONFIG_X86_CPU_RESCTRL_INTEL_AET */
 
 #else
 
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 017a19143ec9..4a89f00aaa01 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -233,24 +233,11 @@ void __init intel_rdt_mbm_apply_quirk(void);
 void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
 void resctrl_arch_mbm_cntr_assign_set_one(struct rdt_resource *r);
 
-#ifdef CONFIG_X86_CPU_RESCTRL_INTEL_AET
 bool intel_aet_pre_mount(void);
 void intel_aet_unmount(void);
 int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val);
 void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r,
 				struct list_head *add_pos);
 bool intel_handle_aet_option(bool force_off, char *tok);
-#else
-static inline bool intel_aet_pre_mount(void) { return false; }
-static inline void intel_aet_unmount(void) { }
-static inline int intel_aet_read_event(int domid, u32 rmid, void *arch_priv, u64 *val)
-{
-	return -EINVAL;
-}
-
-static inline void intel_aet_mon_domain_setup(int cpu, int id, struct rdt_resource *r,
-					      struct list_head *add_pos) { }
-static inline bool intel_handle_aet_option(bool force_off, char *tok) { return false; }
-#endif
 
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f3f7cb01d69d..77fd5529542a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -515,7 +515,7 @@ config X86_MPPARSE
 
 config X86_CPU_RESCTRL
 	bool "x86 CPU resource control support"
-	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
+	depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
 	depends on MISC_FILESYSTEMS
 	select ARCH_HAS_CPU_RESCTRL
 	select RESCTRL_FS
@@ -536,19 +536,6 @@ config X86_CPU_RESCTRL
 
 	  Say N if unsure.
 
-config X86_CPU_RESCTRL_INTEL_AET
-	bool "Intel Application Energy Telemetry"
-	depends on X86_64 && X86_CPU_RESCTRL && CPU_SUP_INTEL && INTEL_PMT_TELEMETRY=y && INTEL_TPMI=y
-	help
-	  Enable per-RMID telemetry events in resctrl.
-
-	  Intel feature that collects per-RMID execution data
-	  about energy consumption, measure of frequency independent
-	  activity and other performance metrics. Data is aggregated
-	  per package.
-
-	  Say N if unsure.
-
 config X86_FRED
 	bool "Flexible Return and Event Delivery"
 	depends on X86_64
diff --git a/arch/x86/kernel/cpu/resctrl/Makefile b/arch/x86/kernel/cpu/resctrl/Makefile
index 273ddfa30836..97ceb4e44dfa 100644
--- a/arch/x86/kernel/cpu/resctrl/Makefile
+++ b/arch/x86/kernel/cpu/resctrl/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_X86_CPU_RESCTRL)		+= core.o rdtgroup.o monitor.o
 obj-$(CONFIG_X86_CPU_RESCTRL)		+= ctrlmondata.o
-obj-$(CONFIG_X86_CPU_RESCTRL_INTEL_AET)	+= intel_aet.o
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= intel_aet.o
 obj-$(CONFIG_RESCTRL_FS_PSEUDO_LOCK)	+= pseudo_lock.o
 
 # To allow define_trace.h's recursive include:
-- 
2.54.0