[RFC PATCH 4/5] irq_work: Trace calls to arch_irq_work_raise()

Valentin Schneider
2022-10-07T15:46:32Z

Adding a tracepoint to send_call_function_single_ipi() covers
irq_work_queue_on() when the CPU isn't the local one - add a tracepoint to
irq_work_raise() to cover the other cases.

Signed-off-by: Valentin Schneider <vschneid@redhat.com>
---
kernel/irq_work.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index 7afa40fe5cc4..5a550b681878 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -22,6 +22,8 @@
#include <asm/processor.h>
#include <linux/kasan.h>

+#include <trace/events/ipi.h>
+
static DEFINE_PER_CPU(struct llist_head, raised_list);
static DEFINE_PER_CPU(struct llist_head, lazy_list);
static DEFINE_PER_CPU(struct task_struct *, irq_workd);
@@ -74,6 +76,14 @@ void __weak arch_irq_work_raise(void)
*/
}

+static inline void irq_work_raise(void)
+{
+ if (arch_irq_work_has_interrupt())
+ trace_ipi_send_cpu(_RET_IP_, smp_processor_id());
+
+ arch_irq_work_raise();
+}
+
/* Enqueue on current CPU, work must already be claimed and preempt disabled */
static void __irq_work_queue_local(struct irq_work *work)
{
@@ -99,7 +109,7 @@ static void __irq_work_queue_local(struct irq_work *work)

/* If the work is "lazy", handle it from next tick if any */
if (!lazy_work || tick_nohz_tick_stopped())
- arch_irq_work_raise();
+ irq_work_raise();
}

/* Enqueue the irq work @work on the current CPU */
--
2.31.1