From 827da44c61419f29ae3be198c342e2147f1a10cb Mon Sep 17 00:00:00 2001 From: John Stultz Date: Mon, 7 Oct 2013 15:51:58 -0700 Subject: net: Explicitly initialize u64_stats_sync structures for lockdep In order to enable lockdep on seqcount/seqlock structures, we must explicitly initialize any locks. The u64_stats_sync structure, uses a seqcount, and thus we need to introduce a u64_stats_init() function and use it to initialize the structure. This unfortunately adds a lot of fairly trivial initialization code to a number of drivers. But the benefit of ensuring correctness makes this worth while. Because these changes are required for lockdep to be enabled, and the changes are quite trivial, I've not yet split this patch out into 30-some separate patches, as I figured it would be better to get the various maintainers thoughts on how to best merge this change along with the seqcount lockdep enablement. Feedback would be appreciated! Signed-off-by: John Stultz Acked-by: Julian Anastasov Signed-off-by: Peter Zijlstra Cc: Alexey Kuznetsov Cc: "David S. Miller" Cc: Eric Dumazet Cc: Hideaki YOSHIFUJI Cc: James Morris Cc: Jesse Gross Cc: Mathieu Desnoyers Cc: "Michael S. Tsirkin" Cc: Mirko Lindner Cc: Patrick McHardy Cc: Roger Luethi Cc: Rusty Russell Cc: Simon Horman Cc: Stephen Hemminger Cc: Steven Rostedt Cc: Thomas Petazzoni Cc: Wensong Zhang Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar --- drivers/net/loopback.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/net/loopback.c') diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c index a17d85a331f1..ac24c27b4b2d 100644 --- a/drivers/net/loopback.c +++ b/drivers/net/loopback.c @@ -137,10 +137,16 @@ static const struct ethtool_ops loopback_ethtool_ops = { static int loopback_dev_init(struct net_device *dev) { + int i; dev->lstats = alloc_percpu(struct pcpu_lstats); if (!dev->lstats) return -ENOMEM; + for_each_possible_cpu(i) { + struct pcpu_lstats *lb_stats; + lb_stats = per_cpu_ptr(dev->lstats, i); + u64_stats_init(&lb_stats->syncp); + } return 0; } -- cgit v1.2.1