[PATCH v2] arm64: stacktrace: Factor out some common code into on_stack()

[Yunfeng Ye]

There are some common codes for stack checking, so factors it out into
the function on_stack().

No functional change.

Signed-off-by: Yunfeng Ye <yeyunfeng@xxxxxxxxxx>
---
v1 -> v2:
 - check 'low' in on_stack() and everybody call on_stack() only

 arch/arm64/include/asm/stacktrace.h | 40 +++++++++++++------------------------
 arch/arm64/kernel/sdei.c            | 28 ++------------------------
 2 files changed, 16 insertions(+), 52 deletions(-)

diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h
index fdb913cc0bcb..fc7613023c19 100644
--- a/arch/arm64/include/asm/stacktrace.h
+++ b/arch/arm64/include/asm/stacktrace.h
@@ -69,12 +69,10 @@ extern void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk,

 DECLARE_PER_CPU(unsigned long *, irq_stack_ptr);

-static inline bool on_irq_stack(unsigned long sp,
+static inline bool on_stack(unsigned long sp, unsigned long low,
+				unsigned long high, enum stack_type type,
 				struct stack_info *info)
 {
-	unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);
-	unsigned long high = low + IRQ_STACK_SIZE;
-
 	if (!low)
 		return false;

@@ -84,12 +82,20 @@ static inline bool on_irq_stack(unsigned long sp,
 	if (info) {
 		info->low = low;
 		info->high = high;
-		info->type = STACK_TYPE_IRQ;
+		info->type = type;
 	}
-
 	return true;
 }

+static inline bool on_irq_stack(unsigned long sp,
+				struct stack_info *info)
+{
+	unsigned long low = (unsigned long)raw_cpu_read(irq_stack_ptr);
+	unsigned long high = low + IRQ_STACK_SIZE;
+
+	return on_stack(sp, low, high, STACK_TYPE_IRQ, info);
+}
+
 static inline bool on_task_stack(const struct task_struct *tsk,
 				 unsigned long sp,
 				 struct stack_info *info)
@@ -97,16 +103,7 @@ static inline bool on_task_stack(const struct task_struct *tsk,
 	unsigned long low = (unsigned long)task_stack_page(tsk);
 	unsigned long high = low + THREAD_SIZE;

-	if (sp < low || sp >= high)
-		return false;
-
-	if (info) {
-		info->low = low;
-		info->high = high;
-		info->type = STACK_TYPE_TASK;
-	}
-
-	return true;
+	return on_stack(sp, low, high, STACK_TYPE_TASK, info);
 }

 #ifdef CONFIG_VMAP_STACK
@@ -118,16 +115,7 @@ static inline bool on_overflow_stack(unsigned long sp,
 	unsigned long low = (unsigned long)raw_cpu_ptr(overflow_stack);
 	unsigned long high = low + OVERFLOW_STACK_SIZE;

-	if (sp < low || sp >= high)
-		return false;
-
-	if (info) {
-		info->low = low;
-		info->high = high;
-		info->type = STACK_TYPE_OVERFLOW;
-	}
-
-	return true;
+	return on_stack(sp, low, high, STACK_TYPE_OVERFLOW, info);
 }
 #else
 static inline bool on_overflow_stack(unsigned long sp,
diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c
index d6259dac62b6..3afed808b474 100644
--- a/arch/arm64/kernel/sdei.c
+++ b/arch/arm64/kernel/sdei.c
@@ -95,19 +95,7 @@ static bool on_sdei_normal_stack(unsigned long sp, struct stack_info *info)
 	unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_normal_ptr);
 	unsigned long high = low + SDEI_STACK_SIZE;

-	if (!low)
-		return false;
-
-	if (sp < low || sp >= high)
-		return false;
-
-	if (info) {
-		info->low = low;
-		info->high = high;
-		info->type = STACK_TYPE_SDEI_NORMAL;
-	}
-
-	return true;
+	return on_stack(sp, low, high, STACK_TYPE_SDEI_NORMAL, info);
 }

 static bool on_sdei_critical_stack(unsigned long sp, struct stack_info *info)
@@ -115,19 +103,7 @@ static bool on_sdei_critical_stack(unsigned long sp, struct stack_info *info)
 	unsigned long low = (unsigned long)raw_cpu_read(sdei_stack_critical_ptr);
 	unsigned long high = low + SDEI_STACK_SIZE;

-	if (!low)
-		return false;
-
-	if (sp < low || sp >= high)
-		return false;
-
-	if (info) {
-		info->low = low;
-		info->high = high;
-		info->type = STACK_TYPE_SDEI_CRITICAL;
-	}
-
-	return true;
+	return on_stack(sp, low, high, STACK_TYPE_SDEI_CRITICAL, info);
 }

 bool _on_sdei_stack(unsigned long sp, struct stack_info *info)
-- 
1.8.3.1