Module Name: src
Committed By: msaitoh
Date: Mon Jun 4 02:42:23 UTC 2018
Modified Files:
src/sys/dev/pci/ixgbe: ixgbe.c ixv.c
Log Message:
Don't call ixgbe_rearm_queues() in ixgbe_local_timer1().
ixgbe_enable_queue() and ixgbe_disable_queue() try to enable/disable queue
interrupt safely. It has the internal counter. When a queue's MSI-X is
received, ixgbe_msix_que() is called (IPL_NET). This function disable the
queue's interrupt by ixgbe_disable_queue() and issues an softint.
ixgbe_handle() queue is called by the softint (IPL_SOFTNET), process TX, RX
and call ixgbe_enable_queue() at the end.
ixgbe_local_timer1() is a callout and run always on CPU 0 (IPL_SOFTCLOCK).
When ixgbe_rearm_queues() called, an MSI-X interrupt is issued for a specific
queue. It may not CPU 0. If this interrupt's ixgbe_msix_que() is called and
sofint_schedule() is called before the last sofint's softint_execute() is not
called, the softint_schedule() fails because of SOFTINT_PENDING. It result
in breaking ixgbe_{enable,disable}_queue()'s internal counter.
ixgbe_local_timer1() is written not to call ixgbe_rearm_queues() if
the interrupt is disabled, but it's called because of unknown bug or a race.
One solution to avoid this problem is to not to use the internal counter,
but it's little difficult. Another solution is stop using
ixgbe_rearm_queues() at all. Essentially, ixgbe_rearm_queues() is not
required (it was added in ixgbe.c rev. 1.43 (2016/12/01)).
ixgbe_rearm_queues() helps for lost interrupt problem but I've never seen it
other than ixgbe_rearm_queues() problem.
XXX pullup-8.
To generate a diff of this commit:
cvs rdiff -u -r1.159 -r1.160 src/sys/dev/pci/ixgbe/ixgbe.c
cvs rdiff -u -r1.103 -r1.104 src/sys/dev/pci/ixgbe/ixv.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/pci/ixgbe/ixgbe.c
diff -u src/sys/dev/pci/ixgbe/ixgbe.c:1.159 src/sys/dev/pci/ixgbe/ixgbe.c:1.160
--- src/sys/dev/pci/ixgbe/ixgbe.c:1.159 Sun Jun 3 10:24:24 2018
+++ src/sys/dev/pci/ixgbe/ixgbe.c Mon Jun 4 02:42:23 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: ixgbe.c,v 1.159 2018/06/03 10:24:24 maxv Exp $ */
+/* $NetBSD: ixgbe.c,v 1.160 2018/06/04 02:42:23 msaitoh Exp $ */
/******************************************************************************
@@ -4411,6 +4411,7 @@ ixgbe_local_timer1(void *arg)
/* Only truely watchdog if all queues show hung */
if (hung == adapter->num_queues)
goto watchdog;
+#if 0 /* XXX Avoid unexpectedly disabling interrupt forever (PR#53294) */
else if (queues != 0) { /* Force an IRQ on queues with work */
que = adapter->queues;
for (i = 0; i < adapter->num_queues; i++, que++) {
@@ -4421,6 +4422,7 @@ ixgbe_local_timer1(void *arg)
mutex_exit(&que->dc_mtx);
}
}
+#endif
out:
callout_reset(&adapter->timer, hz, ixgbe_local_timer, adapter);
@@ -6643,7 +6645,7 @@ ixgbe_handle_link(void *context)
/************************************************************************
* ixgbe_rearm_queues
************************************************************************/
-static void
+static __inline void
ixgbe_rearm_queues(struct adapter *adapter, u64 queues)
{
u32 mask;
Index: src/sys/dev/pci/ixgbe/ixv.c
diff -u src/sys/dev/pci/ixgbe/ixv.c:1.103 src/sys/dev/pci/ixgbe/ixv.c:1.104
--- src/sys/dev/pci/ixgbe/ixv.c:1.103 Sun Jun 3 10:24:24 2018
+++ src/sys/dev/pci/ixgbe/ixv.c Mon Jun 4 02:42:23 2018
@@ -1,4 +1,4 @@
-/*$NetBSD: ixv.c,v 1.103 2018/06/03 10:24:24 maxv Exp $*/
+/*$NetBSD: ixv.c,v 1.104 2018/06/04 02:42:23 msaitoh Exp $*/
/******************************************************************************
@@ -1266,9 +1266,11 @@ ixv_local_timer_locked(void *arg)
/* Only truly watchdog if all queues show hung */
if (hung == adapter->num_queues)
goto watchdog;
+#if 0
else if (queues != 0) { /* Force an IRQ on queues with work */
ixv_rearm_queues(adapter, queues);
}
+#endif
callout_reset(&adapter->timer, hz, ixv_local_timer, adapter);
