sched/rt, arm64: Use CONFIG_PREEMPTION

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the Kconfig dependency, entry code and preemption handling over
to use CONFIG_PREEMPTION. Add PREEMPT_RT output in show_stack().

[bigeasy: +traps.c, Kconfig]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20191015191821.11479-3-bigeasy@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/arm64/Kconfig

@@ -34,32 +34,32 @@ config ARM64
 	select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
 	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG
-	select ARCH_INLINE_READ_LOCK if !PREEMPT
-	select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
-	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
-	select ARCH_INLINE_READ_UNLOCK if !PREEMPT
-	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
-	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
-	select ARCH_INLINE_WRITE_LOCK if !PREEMPT
-	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
-	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
-	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
-	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
-	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
-	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
-	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
-	select ARCH_INLINE_SPIN_LOCK if !PREEMPT
-	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
-	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
-	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
-	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
-	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
-	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
+	select ARCH_INLINE_READ_LOCK if !PREEMPTION
+	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
+	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
+	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
+	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
+	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
+	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
+	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
+	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
+	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
+	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
+	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
+	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
+	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
+	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
+	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
+	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
+	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
+	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
+	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
+	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
 	select ARCH_KEEP_MEMBLOCK
 	select ARCH_USE_CMPXCHG_LOCKREF
 	select ARCH_USE_QUEUED_RWLOCKS

arch/arm64/crypto/sha256-glue.c

@@ -97,7 +97,7 @@ static int sha256_update_neon(struct shash_desc *desc, const u8 *data,
 		 * input when running on a preemptible kernel, but process the
 		 * data block by block instead.
 		 */
-		if (IS_ENABLED(CONFIG_PREEMPT) &&
+		if (IS_ENABLED(CONFIG_PREEMPTION) &&
 		    chunk + sctx->count % SHA256_BLOCK_SIZE > SHA256_BLOCK_SIZE)
 			chunk = SHA256_BLOCK_SIZE -
 				sctx->count % SHA256_BLOCK_SIZE;

arch/arm64/include/asm/assembler.h

@@ -699,8 +699,8 @@ USER(\label, ic	ivau, \tmp2)			// invalidate I line PoU
  * where <label> is optional, and marks the point where execution will resume
  * after a yield has been performed. If omitted, execution resumes right after
  * the endif_yield_neon invocation. Note that the entire sequence, including
- * the provided patchup code, will be omitted from the image if CONFIG_PREEMPT
- * is not defined.
+ * the provided patchup code, will be omitted from the image if
+ * CONFIG_PREEMPTION is not defined.
  *
  * As a convenience, in the case where no patchup code is required, the above
  * sequence may be abbreviated to
@@ -728,7 +728,7 @@ USER(\label, ic	ivau, \tmp2)			// invalidate I line PoU
 	.endm
 
 	.macro		if_will_cond_yield_neon
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	get_current_task	x0
 	ldr		x0, [x0, #TSK_TI_PREEMPT]
 	sub		x0, x0, #PREEMPT_DISABLE_OFFSET

arch/arm64/include/asm/preempt.h

@@ -79,11 +79,11 @@ static inline bool should_resched(int preempt_offset)
 	return pc == preempt_offset;
 }
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 void preempt_schedule(void);
 #define __preempt_schedule() preempt_schedule()
 void preempt_schedule_notrace(void);
 #define __preempt_schedule_notrace() preempt_schedule_notrace()
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
 
 #endif /* __ASM_PREEMPT_H */

arch/arm64/kernel/entry.S

@@ -604,7 +604,7 @@ el1_irq:
 
 	irq_handler
 
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
 	ldr	x24, [tsk, #TSK_TI_PREEMPT]	// get preempt count
 alternative_if ARM64_HAS_IRQ_PRIO_MASKING
 	/*

arch/arm64/kernel/traps.c

@@ -144,9 +144,12 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
 
 #ifdef CONFIG_PREEMPT
 #define S_PREEMPT " PREEMPT"
+#elif defined(CONFIG_PREEMPT_RT)
+#define S_PREEMPT " PREEMPT_RT"
 #else
 #define S_PREEMPT ""
 #endif
+
 #define S_SMP " SMP"
 
 static int __die(const char *str, int err, struct pt_regs *regs)