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| * pkt_sched: fix virtual-start-time update in QFQPaolo Valente2012-09-191-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the old timestamps of a class, say cl, are stale when the class becomes active, then QFQ may assign to cl a much higher start time than the maximum value allowed. This may happen when QFQ assigns to the start time of cl the finish time of a group whose classes are characterized by a higher value of the ratio max_class_pkt/weight_of_the_class with respect to that of cl. Inserting a class with a too high start time into the bucket list corrupts the data structure and may eventually lead to crashes. This patch limits the maximum start time assigned to a class. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
* | pkt_sched: Fix warning false positives.David S. Miller2012-09-271-1/+1
|/ | | | | | | | | | | | | | GCC refuses to recognize that all error control flows do in fact set err to something. Add an explicit initialization to shut it up. net/sched/sch_drr.c: In function ‘drr_enqueue’: net/sched/sch_drr.c:359:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized] net/sched/sch_qfq.c: In function ‘qfq_enqueue’: net/sched/sch_qfq.c:885:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized] Signed-off-by: David S. Miller <davem@davemloft.net>
* sched: add missing group change to qfq_change_classPaolo Valente2012-08-081-26/+69
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [Resending again, as the text was corrupted by the email client] To speed up operations, QFQ internally divides classes into groups. Which group a class belongs to depends on the ratio between the maximum packet length and the weight of the class. Unfortunately the function qfq_change_class lacks the steps for changing the group of a class when the ratio max_pkt_len/weight of the class changes. For example, when the last of the following three commands is executed, the group of class 1:1 is not correctly changed: tc disc add dev XXX root handle 1: qfq tc class add dev XXX parent 1: qfq classid 1:1 weight 1 tc class change dev XXX parent 1: classid 1:1 qfq weight 4 Not changing the group of a class does not affect the long-term bandwidth guaranteed to the class, as the latter is independent of the maximum packet length, and correctly changes (only) if the weight of the class changes. In contrast, if the group of the class is not updated, the class is still guaranteed the short-term bandwidth and packet delay related to its old group, instead of the guarantees that it should receive according to its new weight and/or maximum packet length. This may also break service guarantees for other classes. This patch adds the missing operations. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: David S. Miller <davem@davemloft.net>
* pkt_sched: Stop using NLA_PUT*().David S. Miller2012-04-011-2/+3
| | | | | | | These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2012-01-041-2/+2
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| * sch_qfq: fix overflow in qfq_update_start()Eric Dumazet2012-01-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | grp->slot_shift is between 22 and 41, so using 32bit wide variables is probably a typo. This could explain QFQ hangs Dave reported to me, after 2^23 packets ? (23 = 64 - 41) Reported-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> CC: Dave Taht <dave.taht@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | sch_qfq: accurate wsum handlingEric Dumazet2012-01-031-8/+9
|/ | | | | | | | | | | | We can underestimate q->wsum in case of "tc class replace ... qfq" and/or qdisc_create_dflt() error. wsum is not really used in fast path, only at qfq qdisc/class setup, to catch user error. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* pkt_sched: QFQ - quick fair queue schedulerstephen hemminger2011-04-041-0/+1137
This is an implementation of the Quick Fair Queue scheduler developed by Fabio Checconi. The same algorithm is already implemented in ipfw in FreeBSD. Fabio had an earlier version developed on Linux, I just cleaned it up. Thanks to Eric Dumazet for testing this under load. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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