Re: [RFC,v2,9/9] hyper_dmabuf: threaded interrupt in Xen-backend

From: Oleksandr Andrushchenko
Date: Tue Apr 10 2018 - 06:04:59 EST


On 02/14/2018 03:50 AM, Dongwon Kim wrote:
Use threaded interrupt intead of regular one because most part of ISR
is time-critical and possibly sleeps

Signed-off-by: Dongwon Kim <dongwon.kim@xxxxxxxxx>
---
.../hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c b/drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c
index 30bc4b6304ac..65af5ddfb2d7 100644
--- a/drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c
+++ b/drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c
@@ -332,11 +332,14 @@ int xen_be_init_tx_rbuf(int domid)
}
/* setting up interrupt */
- ret = bind_evtchn_to_irqhandler(alloc_unbound.port,
- front_ring_isr, 0,
- NULL, (void *) ring_info);
+ ring_info->irq = bind_evtchn_to_irq(alloc_unbound.port);
- if (ret < 0) {
+ ret = request_threaded_irq(ring_info->irq,
+ NULL,
+ front_ring_isr,
+ IRQF_ONESHOT, NULL, ring_info);
+
Why don't you go with threaded IRQ from the beginning and change it
in the patch #9?
+ if (ret != 0) {
dev_err(hy_drv_priv->dev,
"Failed to setup event channel\n");
close.port = alloc_unbound.port;
@@ -348,7 +351,6 @@ int xen_be_init_tx_rbuf(int domid)
}
ring_info->rdomain = domid;
- ring_info->irq = ret;
ring_info->port = alloc_unbound.port;
mutex_init(&ring_info->lock);
@@ -535,9 +537,10 @@ int xen_be_init_rx_rbuf(int domid)
if (!xen_comm_find_tx_ring(domid))
ret = xen_be_init_tx_rbuf(domid);
- ret = request_irq(ring_info->irq,
- back_ring_isr, 0,
- NULL, (void *)ring_info);
+ ret = request_threaded_irq(ring_info->irq,
+ NULL,
+ back_ring_isr, IRQF_ONESHOT,
+ NULL, (void *)ring_info);
Ditto
return ret;