[PATCH net-next v2 5/7] net: ipa: disable interrupt and NAPI after channel stop

From: Alex Elder
Date: Mon Feb 01 2021 - 12:31:26 EST


Disable both the I/O completion interrupt and NAPI polling on a
channel *after* we successfully stop it rather than before. This
ensures a completion occurring just before the channel is stopped
gets processed.

Enable NAPI polling and the interrupt *before* starting a channel
rather than after, to be symmetric. A stopped channel won't
generate any completion interrupts anyway.

Enable NAPI before the interrupt and disable it afterward.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
v2: Update code for *both* NAPI and the completion interrupt.

drivers/net/ipa/gsi.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c
index 565c785e33a25..93e1d29b28385 100644
--- a/drivers/net/ipa/gsi.c
+++ b/drivers/net/ipa/gsi.c
@@ -860,15 +860,18 @@ static int __gsi_channel_start(struct gsi_channel *channel, bool start)
struct gsi *gsi = channel->gsi;
int ret;

+ napi_enable(&channel->napi);
+ gsi_irq_ieob_enable_one(gsi, channel->evt_ring_id);
+
mutex_lock(&gsi->mutex);

ret = start ? gsi_channel_start_command(channel) : 0;

mutex_unlock(&gsi->mutex);

- if (!ret) {
- gsi_irq_ieob_enable_one(gsi, channel->evt_ring_id);
- napi_enable(&channel->napi);
+ if (ret) {
+ gsi_irq_ieob_disable_one(gsi, channel->evt_ring_id);
+ napi_disable(&channel->napi);
}

return ret;
@@ -908,14 +911,11 @@ static int __gsi_channel_stop(struct gsi_channel *channel, bool stop)
int ret;

gsi_channel_trans_quiesce(channel);
- napi_disable(&channel->napi);
- gsi_irq_ieob_disable_one(gsi, channel->evt_ring_id);

ret = stop ? gsi_channel_stop_retry(channel) : 0;
-
- if (ret) {
- gsi_irq_ieob_enable_one(gsi, channel->evt_ring_id);
- napi_enable(&channel->napi);
+ if (!ret) {
+ gsi_irq_ieob_disable_one(gsi, channel->evt_ring_id);
+ napi_disable(&channel->napi);
}

return ret;
--
2.27.0