BMC/Intel-BMC/linux.git/net/sched/sch_mq.c, branch dev

net: sched: enable per cpu qstats

2014-09-30T05:02:26+00:00

After previous patches to simplify qstats the qstats can be made per cpu with a packed union in Qdisc struct. Signed-off-by: John Fastabend Signed-off-by: David S. Miller

net: sched: restrict use of qstats qlen

2014-09-30T05:02:26+00:00

This removes the use of qstats->qlen variable from the classifiers and makes it an explicit argument to gnet_stats_copy_queue(). The qlen represents the qdisc queue length and is packed into the qstats at the last moment before passnig to user space. By handling it explicitely we avoid, in the percpu stats case, having to figure out which per_cpu variable to put it in. It would probably be best to remove it from qstats completely but qstats is a user space ABI and can't be broken. A future patch could make an internal only qstats structure that would avoid having to allocate an additional u32 variable on the Qdisc struct. This would make the qstats struct 128bits instead of 128+32. Signed-off-by: John Fastabend Signed-off-by: David S. Miller

net: sched: make bstats per cpu and estimator RCU safe

2014-09-30T05:02:26+00:00

In order to run qdisc's without locking statistics and estimators need to be handled correctly. To resolve bstats make the statistics per cpu. And because this is only needed for qdiscs that are running without locks which is not the case for most qdiscs in the near future only create percpu stats when qdiscs set the TCQ_F_CPUSTATS flag. Next because estimators use the bstats to calculate packets per second and bytes per second the estimator code paths are updated to use the per cpu statistics. Signed-off-by: John Fastabend Signed-off-by: David S. Miller

pkt_sched: give visibility to mq slave qdiscs

2013-12-10T00:54:47+00:00

Commit 6da7c8fcbcbd ("qdisc: allow setting default queuing discipline") added the ability to change default qdisc from pfifo_fast to say fq But as most modern ethernet devices are multiqueue, we cant really see all the statistics from "tc -s qdisc show", as the default root qdisc is mq. This patch adds the calls to qdisc_list_add() to mq and mqprio Signed-off-by: Eric Dumazet Cc: Stephen Hemminger Signed-off-by: David S. Miller

qdisc: allow setting default queuing discipline

2013-08-31T04:32:32+00:00

By default, the pfifo_fast queue discipline has been used by default for all devices. But we have better choices now. This patch allow setting the default queueing discipline with sysctl. This allows easy use of better queueing disciplines on all devices without having to use tc qdisc scripts. It is intended to allow an easy path for distributions to make fq_codel or sfq the default qdisc. This patch also makes pfifo_fast more of a first class qdisc, since it is now possible to manually override the default and explicitly use pfifo_fast. The behavior for systems who do not use the sysctl is unchanged, they still get pfifo_fast Also removes leftover random # in sysctl net core. Signed-off-by: Stephen Hemminger Acked-by: Eric Dumazet Signed-off-by: David S. Miller

pkt_sched: avoid requeues if possible

2012-12-12T05:16:47+00:00

With BQL being deployed, we can more likely have following behavior : We dequeue a packet from qdisc in dequeue_skb(), then we realize target tx queue is in XOFF state in sch_direct_xmit(), and we have to hold the skb into gso_skb for later. This shows in stats (tc -s qdisc dev eth0) as requeues. Problem of these requeues is that high priority packets can not be dequeued as long as this (possibly low prio and big TSO packet) is not removed from gso_skb. At 1Gbps speed, a full size TSO packet is 500 us of extra latency. In some cases, we know that all packets dequeued from a qdisc are for a particular and known txq : - If device is non multi queue - For all MQ/MQPRIO slave qdiscs This patch introduces a new qdisc flag, TCQ_F_ONETXQUEUE to mark this capability, so that dequeue_skb() is allowed to dequeue a packet only if the associated txq is not stopped. This indeed reduce latencies for high prio packets (or improve fairness with sfq/fq_codel), and almost remove qdisc 'requeues'. Signed-off-by: Eric Dumazet Cc: Jamal Hadi Salim Cc: John Fastabend Signed-off-by: David S. Miller

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

2011-10-31T23:30:30+00:00

These files are non modular, but need to export symbols using the macros now living in export.h -- call out the include so that things won't break when we remove the implicit presence of module.h from everywhere. Signed-off-by: Paul Gortmaker

net_sched: TCQ_F_CAN_BYPASS generalization

2011-01-22T00:26:09+00:00

Now qdisc stab is handled before TCQ_F_CAN_BYPASS test in __dev_xmit_skb(), we can generalize TCQ_F_CAN_BYPASS to other qdiscs than pfifo_fast : pfifo, bfifo, pfifo_head_drop and sfq SFQ is special because it can have external classifiers, and in these cases, we cannot bypass queue discipline (packet could be dropped by classifier) without admin asking it, or further changes. Its worth doing this, especially for SFQ, avoiding dirtying memory in case no packets are already waiting in queue. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

net_sched: remove the unused parameter of qdisc_create_dflt()

2010-10-21T10:09:47+00:00

The first parameter dev isn't in use in qdisc_create_dflt(). Signed-off-by: Changli Gao Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller

net: Remove unnecessary returns from void function()s

2010-05-18T06:23:14+00:00

This patch removes from net/ (but not any netfilter files) all the unnecessary return; statements that precede the last closing brace of void functions. It does not remove the returns that are immediately preceded by a label as gcc doesn't like that. Done via: $ grep -rP --include=*.[ch] -l "return;\n}" net/ | \ xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }' Signed-off-by: Joe Perches Signed-off-by: David S. Miller