[RFC PATCH 15/86] Revert "preempt: Restore preemption model selection configs"

[Ankur Arora]

This is a partial revert of commit a8b76910e465d718effce0cad306a21fa4f3526b.

There have been some structural changes to init/Makefile so we leave it
be.

Signed-off-by: Ankur Arora <ankur.a.arora@xxxxxxxxxx>
---
 include/linux/kernel.h   |  2 +-
 include/linux/vermagic.h |  2 +-
 kernel/Kconfig.preempt   | 42 ++++++++++++++++++++--------------------
 kernel/sched/core.c      |  6 +++---
 4 files changed, 26 insertions(+), 26 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index cdce553479b4..b9121007fd0b 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -96,7 +96,7 @@
 struct completion;
 struct user;
 
-#ifdef CONFIG_PREEMPT_VOLUNTARY_BUILD
+#ifdef CONFIG_PREEMPT_VOLUNTARY
 
 extern int __cond_resched(void);
 # define might_resched() __cond_resched()
diff --git a/include/linux/vermagic.h b/include/linux/vermagic.h
index a54046bf37e5..e710e3762c52 100644
--- a/include/linux/vermagic.h
+++ b/include/linux/vermagic.h
@@ -15,7 +15,7 @@
 #else
 #define MODULE_VERMAGIC_SMP ""
 #endif
-#ifdef CONFIG_PREEMPT_BUILD
+#ifdef CONFIG_PREEMPT
 #define MODULE_VERMAGIC_PREEMPT "preempt "
 #elif defined(CONFIG_PREEMPT_RT)
 #define MODULE_VERMAGIC_PREEMPT "preempt_rt "
diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index ce77f0265660..60f1bfc3c7b2 100644
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -1,23 +1,12 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-config PREEMPT_NONE_BUILD
-	bool
-
-config PREEMPT_VOLUNTARY_BUILD
-	bool
-
-config PREEMPT_BUILD
-	bool
-	select PREEMPTION
-	select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
-
 choice
 	prompt "Preemption Model"
-	default PREEMPT_NONE
+	default PREEMPT_NONE_BEHAVIOUR
 
-config PREEMPT_NONE
+config PREEMPT_NONE_BEHAVIOUR
 	bool "No Forced Preemption (Server)"
-	select PREEMPT_NONE_BUILD if !PREEMPT_DYNAMIC
+	select PREEMPT_NONE if !PREEMPT_DYNAMIC
 	help
 	  This is the traditional Linux preemption model, geared towards
 	  throughput. It will still provide good latencies most of the
@@ -29,10 +18,10 @@ config PREEMPT_NONE
 	  raw processing power of the kernel, irrespective of scheduling
 	  latencies.
 
-config PREEMPT_VOLUNTARY
+config PREEMPT_VOLUNTARY_BEHAVIOUR
 	bool "Voluntary Kernel Preemption (Desktop)"
 	depends on !ARCH_NO_PREEMPT
-	select PREEMPT_VOLUNTARY_BUILD if !PREEMPT_DYNAMIC
+	select PREEMPT_VOLUNTARY if !PREEMPT_DYNAMIC
 	help
 	  This option reduces the latency of the kernel by adding more
 	  "explicit preemption points" to the kernel code. These new
@@ -48,10 +37,10 @@ config PREEMPT_VOLUNTARY
 
 	  Select this if you are building a kernel for a desktop system.
 
-config PREEMPT
+config PREEMPT_BEHAVIOUR
 	bool "Preemptible Kernel (Low-Latency Desktop)"
 	depends on !ARCH_NO_PREEMPT
-	select PREEMPT_BUILD
+	select PREEMPT
 	help
 	  This option reduces the latency of the kernel by making
 	  all kernel code (that is not executing in a critical section)
@@ -69,7 +58,7 @@ config PREEMPT
 
 config PREEMPT_RT
 	bool "Fully Preemptible Kernel (Real-Time)"
-	depends on EXPERT && ARCH_SUPPORTS_RT
+	depends on EXPERT && ARCH_SUPPORTS_RT && !PREEMPT_DYNAMIC
 	select PREEMPTION
 	help
 	  This option turns the kernel into a real-time kernel by replacing
@@ -86,6 +75,17 @@ config PREEMPT_RT
 
 endchoice
 
+config PREEMPT_NONE
+	bool
+
+config PREEMPT_VOLUNTARY
+	bool
+
+config PREEMPT
+	bool
+	select PREEMPTION
+	select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
+
 config PREEMPT_COUNT
        bool
 
@@ -95,8 +95,8 @@ config PREEMPTION
 
 config PREEMPT_DYNAMIC
 	bool "Preemption behaviour defined on boot"
-	depends on HAVE_PREEMPT_DYNAMIC && !PREEMPT_RT
-	select PREEMPT_BUILD
+	depends on HAVE_PREEMPT_DYNAMIC
+	select PREEMPT
 	default y
 	help
 	  This option allows to define the preemption model on the kernel
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 50e1133cacc9..d3828d90bf84 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7073,13 +7073,13 @@ __setup("preempt=", setup_preempt_mode);
 static void __init preempt_dynamic_init(void)
 {
 	if (preempt_dynamic_mode == preempt_dynamic_undefined) {
-		if (IS_ENABLED(CONFIG_PREEMPT_NONE)) {
+		if (IS_ENABLED(CONFIG_PREEMPT_NONE_BEHAVIOUR)) {
 			sched_dynamic_update(preempt_dynamic_none);
-		} else if (IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY)) {
+		} else if (IS_ENABLED(CONFIG_PREEMPT_VOLUNTARY_BEHAVIOUR)) {
 			sched_dynamic_update(preempt_dynamic_voluntary);
 		} else {
 			/* Default static call setting, nothing to do */
-			WARN_ON_ONCE(!IS_ENABLED(CONFIG_PREEMPT));
+			WARN_ON_ONCE(!IS_ENABLED(CONFIG_PREEMPT_BEHAVIOUR));
 			preempt_dynamic_mode = preempt_dynamic_full;
 			pr_info("Dynamic Preempt: full\n");
 		}
-- 
2.31.1