Re: [patch net-next v8 2/3] net: core: Add offload stats to if_stats_msg
flat view
From: Nikolay Aleksandrov <hidden>
Date: 2016-09-09 13:36:22
On Sep 8, 2016, at 9:19 AM, Jiri Pirko [off-list ref] wrote: From: Nogah Frankel <redacted> Add a nested attribute of offload stats to if_stats_msg named IFLA_STATS_LINK_OFFLOAD_XSTATS. Under it, add SW stats, meaning stats only per packets that went via slowpath to the cpu, named IFLA_OFFLOAD_XSTATS_CPU_HIT. Signed-off-by: Nogah Frankel <redacted> Signed-off-by: Jiri Pirko <redacted> --- include/uapi/linux/if_link.h | 9 ++++ net/core/rtnetlink.c | 97 ++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 102 insertions(+), 4 deletions(-)
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quoted hunk ↗ jump to hunk
@@ -3655,6 +3725,22 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,} } + if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_OFFLOAD_XSTATS, + *idxattr)) { + attr = nla_nest_start(skb, IFLA_STATS_LINK_OFFLOAD_XSTATS); + if (!attr) + goto nla_put_failure; + + err = rtnl_get_offload_stats(skb, dev); + if (err == -ENODATA) + nla_nest_cancel(skb, attr); + else + nla_nest_end(skb, attr); + + if ((err) && (err != -ENODATA)) + goto nla_put_failure; + } +
Hmm, actually on a second read I think there’s a potential problem here. Since you don’t set *idxattr and if the space isn’t enough the dump will get restarted and this will lead to an infinite loop. I.e. if the previous attributes filled the skb and there’s not enough room for this one, it will return an error but *idxattr will be == 0 from the previous attribute thus the whole dump will be restarted (this is in case someone requests this attribute with some of the others of course). Cheers, Nik
quoted hunk ↗ jump to hunk
nlmsg_end(skb, nlh); return 0;@@ -3712,6 +3798,9 @@ static size_t if_nlmsg_stats_size(const struct net_device *dev,} } + if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_OFFLOAD_XSTATS, 0)) + size += rtnl_get_offload_stats_size(dev); + return size; } -- 2.5.5