[PATCH 08/15] x86/irq: Factor out calling ISR from common_interrupt

Jacob Pan
2024-01-26T23:37:27Z

Prepare for calling external IRQ handlers directly from the posted MSI
demultiplexing loop. Extract the common code with common interrupt to
avoid code duplication.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
arch/x86/kernel/irq.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index f6546f83d616..1a1762baf85f 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -242,18 +242,10 @@ static __always_inline void handle_irq(struct irq_desc *desc,
__handle_irq(desc, regs);
}

-/*
- * common_interrupt() handles all normal device IRQ's (the special SMP
- * cross-CPU interrupts have their own entry points).
- */
-DEFINE_IDTENTRY_IRQ(common_interrupt)
+static __always_inline void call_irq_handler(int vector, struct pt_regs *regs)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
struct irq_desc *desc;

- /* entry code tells RCU that we're not quiescent. Check it. */
- RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
-
desc = __this_cpu_read(vector_irq[vector]);
if (likely(!IS_ERR_OR_NULL(desc))) {
handle_irq(desc, regs);
@@ -268,7 +260,20 @@ DEFINE_IDTENTRY_IRQ(common_interrupt)
__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
}
}
+}
+
+/*
+ * common_interrupt() handles all normal device IRQ's (the special SMP
+ * cross-CPU interrupts have their own entry points).
+ */
+DEFINE_IDTENTRY_IRQ(common_interrupt)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ /* entry code tells RCU that we're not quiescent. Check it. */
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");

+ call_irq_handler(vector, regs);
set_irq_regs(old_regs);
}

--
2.25.1