From patchwork Tue Apr 3 07:06:29 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: /proc/net/dev is funky in 3.3.0 From: Eric Dumazet X-Patchwork-Id: 150330 X-Patchwork-Delegate: davem@davemloft.net Message-Id: <1333436789.18626.43.camel@edumazet-glaptop> To: Ben Greear Cc: NetDev Date: Tue, 03 Apr 2012 09:06:29 +0200 On Tue, 2012-04-03 at 08:36 +0200, Eric Dumazet wrote: > Hmm, I think I understand, commit f04565ddf52 added a regression here, I > will send a fix. > If you want to try following patch, please do so, I cant try it right now... I'll provide a proper changelog/attributions in a couple of hours, and make tests myself of course. Thanks net/core/dev.c | 46 ++++++++++++---------------------------------- 1 file changed, 12 insertions(+), 34 deletions(-) --- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/net/core/dev.c b/net/core/dev.c index 6c7dc9d..f7e7de3 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4028,54 +4028,45 @@ static int dev_ifconf(struct net *net, char __user *arg) #ifdef CONFIG_PROC_FS -#define BUCKET_SPACE (32 - NETDEV_HASHBITS) +#define BUCKET_SPACE (32 - NETDEV_HASHBITS - 1) struct dev_iter_state { struct seq_net_private p; - unsigned int pos; /* bucket << BUCKET_SPACE + offset */ }; #define get_bucket(x) ((x) >> BUCKET_SPACE) #define get_offset(x) ((x) & ((1 << BUCKET_SPACE) - 1)) #define set_bucket_offset(b, o) ((b) << BUCKET_SPACE | (o)) -static inline struct net_device *dev_from_same_bucket(struct seq_file *seq) +static inline struct net_device *dev_from_same_bucket(struct seq_file *seq, loff_t *pos) { - struct dev_iter_state *state = seq->private; struct net *net = seq_file_net(seq); struct net_device *dev; struct hlist_node *p; struct hlist_head *h; - unsigned int count, bucket, offset; + unsigned int count = 0, offset = get_offset(*pos); - bucket = get_bucket(state->pos); - offset = get_offset(state->pos); - h = &net->dev_name_head[bucket]; - count = 0; + h = &net->dev_name_head[get_bucket(*pos)]; hlist_for_each_entry_rcu(dev, p, h, name_hlist) { - if (count++ == offset) { - state->pos = set_bucket_offset(bucket, count); + if (++count == offset) return dev; - } } return NULL; } -static inline struct net_device *dev_from_new_bucket(struct seq_file *seq) +static inline struct net_device *dev_from_bucket(struct seq_file *seq, loff_t *pos) { - struct dev_iter_state *state = seq->private; struct net_device *dev; unsigned int bucket; - bucket = get_bucket(state->pos); do { - dev = dev_from_same_bucket(seq); + dev = dev_from_same_bucket(seq, pos); if (dev) return dev; - bucket++; - state->pos = set_bucket_offset(bucket, 0); + bucket = get_bucket(*pos); + *pos = set_bucket_offset(bucket + 1, 1); } while (bucket < NETDEV_HASHENTRIES); return NULL; @@ -4088,33 +4079,20 @@ static inline struct net_device *dev_from_new_bucket(struct seq_file *seq) void *dev_seq_start(struct seq_file *seq, loff_t *pos) __acquires(RCU) { - struct dev_iter_state *state = seq->private; - rcu_read_lock(); if (!*pos) return SEQ_START_TOKEN; - /* check for end of the hash */ - if (state->pos == 0 && *pos > 1) + if (get_bucket(*pos) >= NETDEV_HASHENTRIES) return NULL; - return dev_from_new_bucket(seq); + return dev_from_bucket(seq, pos); } void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos) { - struct net_device *dev; - ++*pos; - - if (v == SEQ_START_TOKEN) - return dev_from_new_bucket(seq); - - dev = dev_from_same_bucket(seq); - if (dev) - return dev; - - return dev_from_new_bucket(seq); + return dev_from_bucket(seq, pos); } void dev_seq_stop(struct seq_file *seq, void *v)