Subject: [PATCH v4 1/2] kexec: Consolidate machine_kexec_mask_interrupts() implementation

From: Eliav Farber <[email-masked]>
Date: Fri, 29 Nov 2024 11:31:18 +0000

Move the machine_kexec_mask_interrupts function to a common location in
kernel/kexec_core.c, removing duplicate implementations from architecture
specific files (arch/arm, arch/arm64, arch/powerpc, and arch/riscv).

This consolidation reduces code duplication and improves maintainability.

The unified function includes an architecture-specific behavior for
CONFIG_ARM64 by conditionally clearing the active interrupt state before
handling other interrupt masking operations.

Signed-off-by: Eliav Farber <[email-masked]>
---
V4 -> V3: Add missing <linux/irqdec.h> include.

 arch/arm/kernel/machine_kexec.c   | 23 ---------------------
 arch/arm64/kernel/machine_kexec.c | 31 -----------------------------
 arch/powerpc/include/asm/kexec.h  |  1 -
 arch/powerpc/kexec/core.c         | 22 ---------------------
 arch/riscv/kernel/machine_kexec.c | 23 ---------------------
 include/linux/kexec.h             |  2 ++
 kernel/kexec_core.c               | 33 +++++++++++++++++++++++++++++++
 7 files changed, 35 insertions(+), 100 deletions(-)

diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index 80ceb5bd2680..dd430477e7c1 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -127,29 +127,6 @@ void crash_smp_send_stop(void)
 	cpus_stopped = 1;
 }
 
-static void machine_kexec_mask_interrupts(void)
-{
-	unsigned int i;
-	struct irq_desc *desc;
-
-	for_each_irq_desc(i, desc) {
-		struct irq_chip *chip;
-
-		chip = irq_desc_get_chip(desc);
-		if (!chip)
-			continue;
-
-		if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
-			chip->irq_eoi(&desc->irq_data);
-
-		if (chip->irq_mask)
-			chip->irq_mask(&desc->irq_data);
-
-		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
-			chip->irq_disable(&desc->irq_data);
-	}
-}
-
 void machine_crash_shutdown(struct pt_regs *regs)
 {
 	local_irq_disable();
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 82e2203d86a3..6f121a0164a4 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -207,37 +207,6 @@ void machine_kexec(struct kimage *kimage)
 	BUG(); /* Should never get here. */
 }
 
-static void machine_kexec_mask_interrupts(void)
-{
-	unsigned int i;
-	struct irq_desc *desc;
-
-	for_each_irq_desc(i, desc) {
-		struct irq_chip *chip;
-		int ret;
-
-		chip = irq_desc_get_chip(desc);
-		if (!chip)
-			continue;
-
-		/*
-		 * First try to remove the active state. If this
-		 * fails, try to EOI the interrupt.
-		 */
-		ret = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
-
-		if (ret && irqd_irq_inprogress(&desc->irq_data) &&
-		    chip->irq_eoi)
-			chip->irq_eoi(&desc->irq_data);
-
-		if (chip->irq_mask)
-			chip->irq_mask(&desc->irq_data);
-
-		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
-			chip->irq_disable(&desc->irq_data);
-	}
-}
-
 /**
  * machine_crash_shutdown - shutdown non-crashing cpus and save registers
  */
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 270ee93a0f7d..601e569303e1 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -61,7 +61,6 @@ struct pt_regs;
 extern void kexec_smp_wait(void);	/* get and clear naca physid, wait for
 					  master to copy new code to 0 */
 extern void default_machine_kexec(struct kimage *image);
-extern void machine_kexec_mask_interrupts(void);
 
 void relocate_new_kernel(unsigned long indirection_page, unsigned long reboot_code_buffer,
 			 unsigned long start_address) __noreturn;
diff --git a/arch/powerpc/kexec/core.c b/arch/powerpc/kexec/core.c
index b8333a49ea5d..58a930a47422 100644
--- a/arch/powerpc/kexec/core.c
+++ b/arch/powerpc/kexec/core.c
@@ -22,28 +22,6 @@
 #include <asm/setup.h>
 #include <asm/firmware.h>
 
-void machine_kexec_mask_interrupts(void) {
-	unsigned int i;
-	struct irq_desc *desc;
-
-	for_each_irq_desc(i, desc) {
-		struct irq_chip *chip;
-
-		chip = irq_desc_get_chip(desc);
-		if (!chip)
-			continue;
-
-		if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
-			chip->irq_eoi(&desc->irq_data);
-
-		if (chip->irq_mask)
-			chip->irq_mask(&desc->irq_data);
-
-		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
-			chip->irq_disable(&desc->irq_data);
-	}
-}
-
 #ifdef CONFIG_CRASH_DUMP
 void machine_crash_shutdown(struct pt_regs *regs)
 {
diff --git a/arch/riscv/kernel/machine_kexec.c b/arch/riscv/kernel/machine_kexec.c
index 3c830a6f7ef4..2306ce3e5f22 100644
--- a/arch/riscv/kernel/machine_kexec.c
+++ b/arch/riscv/kernel/machine_kexec.c
@@ -114,29 +114,6 @@ void machine_shutdown(void)
 #endif
 }
 
-static void machine_kexec_mask_interrupts(void)
-{
-	unsigned int i;
-	struct irq_desc *desc;
-
-	for_each_irq_desc(i, desc) {
-		struct irq_chip *chip;
-
-		chip = irq_desc_get_chip(desc);
-		if (!chip)
-			continue;
-
-		if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
-			chip->irq_eoi(&desc->irq_data);
-
-		if (chip->irq_mask)
-			chip->irq_mask(&desc->irq_data);
-
-		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
-			chip->irq_disable(&desc->irq_data);
-	}
-}
-
 /*
  * machine_crash_shutdown - Prepare to kexec after a kernel crash
  *
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index f0e9f8eda7a3..9dac0524c0be 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -375,6 +375,8 @@ extern void machine_kexec(struct kimage *image);
 extern int machine_kexec_prepare(struct kimage *image);
 extern void machine_kexec_cleanup(struct kimage *image);
 extern int kernel_kexec(void);
+extern void machine_kexec_mask_interrupts(void);
+
 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 						unsigned int order);
 
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index c0caa14880c3..777191458544 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -40,6 +40,7 @@
 #include <linux/hugetlb.h>
 #include <linux/objtool.h>
 #include <linux/kmsg_dump.h>
+#include <linux/irqdesc.h>
 
 #include <asm/page.h>
 #include <asm/sections.h>
@@ -1072,3 +1073,35 @@ int kernel_kexec(void)
 	kexec_unlock();
 	return error;
 }
+
+void machine_kexec_mask_interrupts(void)
+{
+	unsigned int i;
+	struct irq_desc *desc;
+
+	for_each_irq_desc(i, desc) {
+		struct irq_chip *chip;
+		int check_eoi = 1;
+
+		chip = irq_desc_get_chip(desc);
+		if (!chip)
+			continue;
+
+		if (IS_ENABLED(CONFIG_ARM64)) {
+			/*
+			 * First try to remove the active state. If this fails, try to EOI the
+			 * interrupt.
+			 */
+			check_eoi = irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false);
+		}
+
+		if (check_eoi && chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data))
+			chip->irq_eoi(&desc->irq_data);
+
+		if (chip->irq_mask)
+			chip->irq_mask(&desc->irq_data);
+
+		if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data))
+			chip->irq_disable(&desc->irq_data);
+	}
+}
-- 
2.40.1