netdev - [PATCH net-next] net: Reduce queue allocation to one in kdump kernel

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Date:	Wed,  8 Jun 2016 18:09:08 +0530
From:	Hariprasad Shenai <hariprasad@...lsio.com>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org, nirranjan@...lsio.com,
	Hariprasad Shenai <hariprasad@...lsio.com>
Subject: [PATCH net-next] net: Reduce queue allocation to one in kdump kernel

When in kdump kernel, reduce memory usage by only using a single Queue
Set for multiqueue devices. So make netif_get_num_default_rss_queues()
return one, when in kdump kernel.

Signed-off-by: Hariprasad Shenai <hariprasad@...lsio.com>
---
 net/core/dev.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index 904ff431d570..161c4627a798 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -139,6 +139,7 @@
 #include <linux/hrtimer.h>
 #include <linux/netfilter_ingress.h>
 #include <linux/sctp.h>
+#include <linux/crash_dump.h>
 
 #include "net-sysfs.h"
 
@@ -2249,7 +2250,8 @@ EXPORT_SYMBOL(netif_set_real_num_rx_queues);
  */
 int netif_get_num_default_rss_queues(void)
 {
-	return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
+	return is_kdump_kernel() ?
+		1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
 }
 EXPORT_SYMBOL(netif_get_num_default_rss_queues);
 
-- 
2.3.4