[PATCH v2 8/8] vfio-pci: add module parameter for default moderation mode
From: Luigi Rizzo
Date: Sun Nov 16 2025 - 13:31:07 EST
The following module parameter enables moderation at boot time for vfio devices.
vfio_pci_core.soft_moderation=1
It can be overridden at runtime via /proc/irq/*/*vfio*/soft_moderation.
See Documentation/core-api/irq/irq-moderation.rst for configuration.
Change-Id: I69ece365fa8eb796c22e088dbe849eddb684e02a
Signed-off-by: Luigi Rizzo <lrizzo@xxxxxxxxxx>
---
drivers/vfio/pci/vfio_pci_intrs.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index 30d3e921cb0de..e54d88cfe601d 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -22,6 +22,8 @@
#include "vfio_pci_priv.h"
+DEFINE_IRQ_MODERATION_MODE_PARAMETER;
+
struct vfio_pci_irq_ctx {
struct vfio_pci_core_device *vdev;
struct eventfd_ctx *trigger;
@@ -317,6 +319,7 @@ static int vfio_intx_enable(struct vfio_pci_core_device *vdev,
vfio_irq_ctx_free(vdev, ctx, 0);
return ret;
}
+ IRQ_MODERATION_SET_DEFAULT_MODE(pdev->irq);
return 0;
}
--
2.52.0.rc1.455.g30608eb744-goog