Commit a3daf3d3 authored by Juergen Gross's avatar Juergen Gross Committed by David S. Miller
Browse files

xen/netback: fix spurious event detection for common event case 



In case of a common event for rx and tx queue the event should be
regarded to be spurious if no rx and no tx requests are pending.

Unfortunately the condition for testing that is wrong causing to
decide a event being spurious if no rx OR no tx requests are
pending.

Fix that plus using local variables for rx/tx pending indicators in
order to split function calls and if condition.

Fixes: 23025393 ("xen/netback: use lateeoi irq binding")
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarPaul Durrant <paul@xen.org>
Reviewed-by: default avatarWei Liu <wl@xen.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6f199552

drivers/net/xen-netback/interface.c

+5 −3
Original line number Diff line number Diff line
@@ -162,13 +162,15 @@ irqreturn_t xenvif_interrupt(int irq, void *dev_id) 
{

	struct xenvif_queue *queue = dev_id;

	int old;

	bool has_rx, has_tx;



	old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending);

	WARN(old, "Interrupt while EOI pending\n");



	/* Use bitwise or as we need to call both functions. */

	if ((!xenvif_handle_tx_interrupt(queue) |

	     !xenvif_handle_rx_interrupt(queue))) {

	has_tx = xenvif_handle_tx_interrupt(queue);

	has_rx = xenvif_handle_rx_interrupt(queue);



	if (!has_rx && !has_tx) {

		atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending);

		xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS);

	}