netdev - [PATCH] rps: make distributing packets fairly among all the online CPUs default

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 23 Mar 2010 14:24:34 +0800
From:	Changli Gao <xiaosuo@...il.com>
To:	"David S. Miller" <davem@...emloft.net>
CC:	Tom Herbert <therbert@...gle.com>, xiaosuo <xiaosuo@...il.com>,
	netdev@...r.kernel.org
Subject: [PATCH] rps: make distributing packets fairly among all the online
 CPUs default

make distributing packets fairly among all the online CPUs default.

Make distributing packets fairly among all the online CPUs default, then
users don't need any explicit configuration to get the benefit of RPS.

Signed-off-by: Changli Gao <xiaosuo@...il.com>
----
net/core/dev.c | 34 ++++++++++++++++++++++++++++++++--
1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index c0e2608..a4246f1 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5234,6 +5234,24 @@ void netif_stacked_transfer_operstate(const struct net_device *rootdev,
 }
 EXPORT_SYMBOL(netif_stacked_transfer_operstate);
 
+static struct rps_map* alloc_rps_map(void)
+{
+	struct rps_map *map;
+	int i, cpu;
+
+	map = kzalloc(max_t(unsigned,
+			    RPS_MAP_SIZE(cpumask_weight(cpu_online_mask)),
+			    L1_CACHE_BYTES), GFP_KERNEL);
+	if (map == NULL)
+		return NULL;
+	i = 0;
+	for_each_online_cpu(cpu)
+		map->cpus[i++] = cpu;
+	map->len = i;
+
+	return map;
+}
+
 /**
  *	register_netdevice	- register a network device
  *	@dev: device to register
@@ -5282,7 +5300,13 @@ int register_netdevice(struct net_device *dev)
 			ret = -ENOMEM;
 			goto out;
 		}
-
+		dev->_rx->rps_map = alloc_rps_map();
+		if (dev->_rx->rps_map == NULL) {
+			kfree(dev->_rx);
+			dev->_rx = NULL;
+			ret = -ENOMEM;
+			goto out;
+		}
 		dev->_rx->first = dev->_rx;
 		atomic_set(&dev->_rx->count, 1);
 		dev->num_rx_queues = 1;
@@ -5688,8 +5712,12 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,
 	 * Set a pointer to first element in the array which holds the
 	 * reference count.
 	 */
-	for (i = 0; i < queue_count; i++)
+	for (i = 0; i < queue_count; i++) {
 		rx[i].first = rx;
+		rx[i].rps_map = alloc_rps_map();
+		if (rx[i].rps_map == NULL)
+			goto free_rx;
+	}
 
 	dev = PTR_ALIGN(p, NETDEV_ALIGN);
 	dev->padded = (char *)dev - (char *)p;
@@ -5723,6 +5751,8 @@ struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,
 	return dev;
 
 free_rx:
+	for (i = 0; i < queue_count; i++)
+		kfree(rx[i].rps_map);
 	kfree(rx);
 free_tx:
 	kfree(tx);


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html