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2014-06-05net: use the new API kvfree()WANG Cong1-6/+1
It is available since v3.15-rc5. Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-12sch_hhf: fix comparison of qlen and limitYang Yingliang1-1/+1
When I use the following command, eth0 cannot send any packets. #tc qdisc add dev eth0 root handle 1: hhf limit 1 Because qlen need be smaller than limit, all packets were dropped. Fix this by qlen *<=* limit. Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-05net: sched: lock imbalance in hhf qdiscJohn Fastabend1-5/+6
hhf_change() takes the sch_tree_lock and releases it but misses the error cases. Fix the missed case here. To reproduce try a command like this, # tc qdisc change dev p3p2 root hhf quantum 40960 non_hh_weight 300000 Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-13net_sched: return nla_nest_end() instead of skb->lenYang Yingliang1-2/+1
nla_nest_end() already has return skb->len, so replace return skb->len with return nla_nest_end instead(). Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15net: replace macros net_random and net_srandom with direct calls to prandomAruna-Hewapathirane1-1/+1
This patch removes the net_random and net_srandom macros and replaces them with direct calls to the prandom ones. As new commits only seem to use prandom_u32 there is no use to keep them around. This change makes it easier to grep for users of prandom_u32. Signed-off-by: Aruna-Hewapathirane <aruna.hewapathirane@gmail.com> Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13HHF qdisc: fix jiffies-time conversion.Terry Lam1-6/+6
This is to be compatible with the use of "get_time" (i.e. default time unit in us) in iproute2 patch for HHF as requested by Stephen. Signed-off-by: Terry Lam <vtlam@google.com> Acked-by: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26hhf: make qdisc ops staticstephen hemminger1-2/+1
This module shouldn't be randomly exporting symbols Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-19net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdiscTerry Lam1-0/+746
This patch implements the first size-based qdisc that attempts to differentiate between small flows and heavy-hitters. The goal is to catch the heavy-hitters and move them to a separate queue with less priority so that bulk traffic does not affect the latency of critical traffic. Currently "less priority" means less weight (2:1 in particular) in a Weighted Deficit Round Robin (WDRR) scheduler. In essence, this patch addresses the "delay-bloat" problem due to bloated buffers. In some systems, large queues may be necessary for obtaining CPU efficiency, or due to the presence of unresponsive traffic like UDP, or just a large number of connections with each having a small amount of outstanding traffic. In these circumstances, HHF aims to reduce the HoL blocking for latency sensitive traffic, while not impacting the queues built up by bulk traffic. HHF can also be used in conjunction with other AQM mechanisms such as CoDel. To capture heavy-hitters, we implement the "multi-stage filter" design in the following paper: C. Estan and G. Varghese, "New Directions in Traffic Measurement and Accounting", in ACM SIGCOMM, 2002. Some configurable qdisc settings through 'tc': - hhf_reset_timeout: period to reset counter values in the multi-stage filter (default 40ms) - hhf_admit_bytes: threshold to classify heavy-hitters (default 128KB) - hhf_evict_timeout: threshold to evict idle heavy-hitters (default 1s) - hhf_non_hh_weight: Weighted Deficit Round Robin (WDRR) weight for non-heavy-hitters (default 2) - hh_flows_limit: max number of heavy-hitter flow entries (default 2048) Note that the ratio between hhf_admit_bytes and hhf_reset_timeout reflects the bandwidth of heavy-hitters that we attempt to capture (25Mbps with the above default settings). The false negative rate (heavy-hitter flows getting away unclassified) is zero by the design of the multi-stage filter algorithm. With 100 heavy-hitter flows, using four hashes and 4000 counters yields a false positive rate (non-heavy-hitters mistakenly classified as heavy-hitters) of less than 1e-4. Signed-off-by: Terry Lam <vtlam@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>