[src/trunk]: src/sys/dev/pci add comment about confusing wm_rxeof() calling.

[knakahara <knakahara%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/59e42468f835
branches:  trunk
changeset: 825682:59e42468f835
user:      knakahara <knakahara%NetBSD.org@localhost>
date:      Fri Jul 28 10:34:58 2017 +0000

description:
add comment about confusing wm_rxeof() calling.

pointed out by msaitoh@n.o.

diffstat:

 sys/dev/pci/if_wm.c |  9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diffs (30 lines):

diff -r 24450beb3e2c -r 59e42468f835 sys/dev/pci/if_wm.c
--- a/sys/dev/pci/if_wm.c       Fri Jul 28 10:21:10 2017 +0000
+++ b/sys/dev/pci/if_wm.c       Fri Jul 28 10:34:58 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_wm.c,v 1.535 2017/07/28 10:21:10 msaitoh Exp $      */
+/*     $NetBSD: if_wm.c,v 1.536 2017/07/28 10:34:58 knakahara Exp $    */
 
 /*
  * Copyright (c) 2001, 2002, 2003, 2004 Wasabi Systems, Inc.
@@ -83,7 +83,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_wm.c,v 1.535 2017/07/28 10:21:10 msaitoh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_wm.c,v 1.536 2017/07/28 10:34:58 knakahara Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_net_mpsafe.h"
@@ -8805,6 +8805,11 @@
                        WM_Q_EVCNT_INCR(rxq, rxintr);
                }
 #endif
+               /*
+                * wm_rxeof() does *not* call upper layer functions directly,
+                * as if_percpuq_enqueue() just call softint_schedule().
+                * So, we can call wm_rxeof() in interrupt context.
+                */
                wm_rxeof(rxq, UINT_MAX);
 
                mutex_exit(rxq->rxq_lock);