[PATCH V2 1/2] virtio-net: fix the set affinity bug when CPU IDs are not consecutive
From: Wanlong Gao <hidden>
Date: 2013-01-07 07:14:47
Also in:
lkml, virtualization
Subsystem:
networking drivers, the rest, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
As M.S.T mentioned, set affinity will not work very well when CPU IDs are not consecutive, this can happen with hot unplug. Fix this bug by traversal the online CPUs. Cc: Rusty Russell <redacted> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Eric Dumazet <redacted> Cc: virtualization@lists.linux-foundation.org Cc: netdev@vger.kernel.org Signed-off-by: Wanlong Gao <redacted> --- drivers/net/virtio_net.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index a6fcf15..b483fb5 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -1016,6 +1016,7 @@ static int virtnet_vlan_rx_kill_vid(struct net_device *dev, u16 vid) static void virtnet_set_affinity(struct virtnet_info *vi, bool set) { int i; + int cpu; /* In multiqueue mode, when the number of cpu is equal to the number of * queue pairs, we let the queue pairs to be private to one cpu by
@@ -1029,16 +1030,25 @@ static void virtnet_set_affinity(struct virtnet_info *vi, bool set) return; } - for (i = 0; i < vi->max_queue_pairs; i++) { - int cpu = set ? i : -1; - virtqueue_set_affinity(vi->rq[i].vq, cpu); - virtqueue_set_affinity(vi->sq[i].vq, cpu); - } + if (set) { + i = 0; + for_each_online_cpu(cpu) { + virtqueue_set_affinity(vi->rq[i].vq, cpu); + virtqueue_set_affinity(vi->sq[i].vq, cpu); + i++; + if (i >= vi->max_queue_pairs) + break; + } - if (set) vi->affinity_hint_set = true; - else + } else { + for(i = 0; i < vi->max_queue_pairs; i++) { + virtqueue_set_affinity(vi->rq[i].vq, -1); + virtqueue_set_affinity(vi->sq[i].vq, -1); + } + vi->affinity_hint_set = false; + } } static void virtnet_get_ringparam(struct net_device *dev,
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1.8.1