Eric Lee / smarc-fsl-linux-kernel

26 Jun, 2016

1 commit

  • 520ac30f4   net_sched: drop packets after root qdisc lock is released ... Browse Code »

    Qdisc performance suffers when packets are dropped at enqueue()
    time because drops (kfree_skb()) are done while qdisc lock is held,
    delaying a dequeue() draining the queue.

    Nominal throughput can be reduced by 50 % when this happens,
    at a time we would like the dequeue() to proceed as fast as possible.

    Even FQ is vulnerable to this problem, while one of FQ goals was
    to provide some flow isolation.

    This patch adds a 'struct sk_buff **to_free' parameter to all
    qdisc->enqueue(), and in qdisc_drop() helper.

    I measured a performance increase of up to 12 %, but this patch
    is a prereq so that future batches in enqueue() can fly.

    Signed-off-by: Eric Dumazet
    Acked-by: Jesper Dangaard Brouer
    Signed-off-by: David S. Miller

    Eric Dumazet
     

09 Jun, 2016

1 commit

  • a09ceb0e0   sched: remove qdisc->drop ... Browse Code »

    after removal of TCA_CBQ_OVL_STRATEGY from cbq scheduler, there are no
    more callers of ->drop() outside of other ->drop functions, i.e.
    nothing calls them.

    Signed-off-by: Florian Westphal
    Signed-off-by: David S. Miller

    Florian Westphal
     

09 Mar, 2016

1 commit

  • f8b33d8e8   net_sched: dsmark: use qdisc_dequeue_peeked() ... Browse Code »

    This fix is for dsmark similar to commit 3557619f0f6f7496ed453d4825e249
    ("net_sched: prio: use qdisc_dequeue_peeked")
    and makes use of qdisc_dequeue_peeked() instead of direct dequeue() call.

    First time, wrr peeks dsmark, which will then peek into sfq.
    sfq dequeues an skb and it's stored in sch->gso_skb.
    Next time, wrr tries to dequeue from dsmark, which will call sfq dequeue
    directly. This results skipping the previously peeked skb.

    So changed dsmark dequeue to call qdisc_dequeue_peeked() instead to use
    peeked skb if exists.

    Signed-off-by: Kyeong Yoo
    Signed-off-by: David S. Miller

    Kyeong Yoo
     

01 Mar, 2016

2 commits

18 Sep, 2015

1 commit

  • 47bbbb30b   sch_dsmark: improve memory locality ... Browse Code »

    Memory placement in sch_dsmark is silly : Better place mask/value
    in the same cache line.

    Also, we can embed small arrays in the first cache line and
    remove a potential cache miss.

    Signed-off-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Eric Dumazet
     

28 Aug, 2015

1 commit

  • 3b3ae8802   net: sched: consolidate tc_classify{,_compat} ... Browse Code »

    For classifiers getting invoked via tc_classify(), we always need an
    extra function call into tc_classify_compat(), as both are being
    exported as symbols and tc_classify() itself doesn't do much except
    handling of reclassifications when tp->classify() returned with
    TC_ACT_RECLASSIFY.

    CBQ and ATM are the only qdiscs that directly call into tc_classify_compat(),
    all others use tc_classify(). When tc actions are being configured
    out in the kernel, tc_classify() effectively does nothing besides
    delegating.

    We could spare this layer and consolidate both functions. pktgen on
    single CPU constantly pushing skbs directly into the netif_receive_skb()
    path with a dummy classifier on ingress qdisc attached, improves
    slightly from 22.3Mpps to 23.1Mpps.

    Signed-off-by: Daniel Borkmann
    Acked-by: Alexei Starovoitov
    Signed-off-by: David S. Miller

    Daniel Borkmann
     

14 Jan, 2015

1 commit

  • d8b9605d2   net: sched: fix skb->protocol use in case of accelerated vlan path ... Browse Code »

    tc code implicitly considers skb->protocol even in case of accelerated
    vlan paths and expects vlan protocol type here. However, on rx path,
    if the vlan header was already stripped, skb->protocol contains value
    of next header. Similar situation is on tx path.

    So for skbs that use skb->vlan_tci for tagging, use skb->vlan_proto instead.

    Reported-by: Jamal Hadi Salim
    Signed-off-by: Jiri Pirko
    Acked-by: Jamal Hadi Salim
    Signed-off-by: David S. Miller

    Jiri Pirko
     

30 Sep, 2014

1 commit

14 Sep, 2014

1 commit

  • 25d8c0d55   net: rcu-ify tcf_proto ... Browse Code »

    rcu'ify tcf_proto this allows calling tc_classify() without holding
    any locks. Updaters are protected by RTNL.

    This patch prepares the core net_sched infrastracture for running
    the classifier/action chains without holding the qdisc lock however
    it does nothing to ensure cls_xxx and act_xxx types also work without
    locking. Additional patches are required to address the fall out.

    Signed-off-by: John Fastabend
    Acked-by: Eric Dumazet
    Signed-off-by: David S. Miller

    John Fastabend
     

01 Jan, 2014

2 commits

11 Dec, 2013

1 commit

04 May, 2012

1 commit

02 Apr, 2012

1 commit

25 Jan, 2011

1 commit

21 Jan, 2011

1 commit

  • 9190b3b32   net_sched: accurate bytes/packets stats/rates ... Browse Code »

    In commit 44b8288308ac9d (net_sched: pfifo_head_drop problem), we fixed
    a problem with pfifo_head drops that incorrectly decreased
    sch->bstats.bytes and sch->bstats.packets

    Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a
    previously enqueued packet, and bstats cannot be changed, so
    bstats/rates are not accurate (over estimated)

    This patch changes the qdisc_bstats updates to be done at dequeue() time
    instead of enqueue() time. bstats counters no longer account for dropped
    frames, and rates are more correct, since enqueue() bursts dont have
    effect on dequeue() rate.

    Signed-off-by: Eric Dumazet
    Acked-by: Stephen Hemminger
    Signed-off-by: David S. Miller

    Eric Dumazet
     

20 Jan, 2011

1 commit

11 Jan, 2011

1 commit

  • bfe0d0298   net_sched: factorize qdisc stats handling ... Browse Code »

    HTB takes into account skb is segmented in stats updates.
    Generalize this to all schedulers.

    They should use qdisc_bstats_update() helper instead of manipulating
    bstats.bytes and bstats.packets

    Add bstats_update() helper too for classes that use
    gnet_stats_basic_packed fields.

    Note : Right now, TCQ_F_CAN_BYPASS shortcurt can be taken only if no
    stab is setup on qdisc.

    Signed-off-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Eric Dumazet
     

21 Oct, 2010

1 commit

30 Mar, 2010

1 commit

  • 5a0e3ad6a   include cleanup: Update gfp.h and slab.h includes to prepare for breaking implic… ... Browse Code »

    …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

20 Nov, 2008

1 commit

14 Nov, 2008

1 commit

  • f30ab418a   pkt_sched: Remove qdisc->ops->requeue() etc. ... Browse Code »

    After implementing qdisc->ops->peek() and changing sch_netem into
    classless qdisc there are no more qdisc->ops->requeue() users. This
    patch removes this method with its wrappers (qdisc_requeue()), and
    also unused qdisc->requeue structure. There are a few minor fixes of
    warnings (htb_enqueue()) and comments btw.

    The idea to kill ->requeue() and a similar patch were first developed
    by David S. Miller.

    Signed-off-by: Jarek Poplawski
    Signed-off-by: David S. Miller

    Jarek Poplawski
     

31 Oct, 2008

1 commit

21 Sep, 2008

1 commit

05 Aug, 2008

2 commits

  • c27f339af   net_sched: Add qdisc __NET_XMIT_BYPASS flag ... Browse Code »

    Patrick McHardy noticed that it would be nice to
    handle NET_XMIT_BYPASS by NET_XMIT_SUCCESS with an internal qdisc flag
    __NET_XMIT_BYPASS and to remove the mapping from dev_queue_xmit().

    David Miller spotted a serious bug in the first
    version of this patch.

    Signed-off-by: Jarek Poplawski
    Signed-off-by: David S. Miller

    Jarek Poplawski
     
  • 378a2f090   net_sched: Add qdisc __NET_XMIT_STOLEN flag ... Browse Code »

    Patrick McHardy noticed:
    "The other problem that affects all qdiscs supporting actions is
    TC_ACT_QUEUED/TC_ACT_STOLEN getting mapped to NET_XMIT_SUCCESS
    even though the packet is not queued, corrupting upper qdiscs'
    qlen counters."

    and later explained:
    "The reason why it translates it at all seems to be to not increase
    the drops counter. Within a single qdisc this could be avoided by
    other means easily, upper qdiscs would still increase the counter
    when we return anything besides NET_XMIT_SUCCESS though.

    This means we need a new NET_XMIT return value to indicate this to
    the upper qdiscs. So I'd suggest to introduce NET_XMIT_STOLEN,
    return that to upper qdiscs and translate it to NET_XMIT_SUCCESS
    in dev_queue_xmit, similar to NET_XMIT_BYPASS."

    David Miller noticed:
    "Maybe these NET_XMIT_* values being passed around should be a set of
    bits. They could be composed of base meanings, combined with specific
    attributes.

    So you could say "NET_XMIT_DROP | __NET_XMIT_NO_DROP_COUNT"

    The attributes get masked out by the top-level ->enqueue() caller,
    such that the base meanings are the only thing that make their
    way up into the stack. If it's only about communication within the
    qdisc tree, let's simply code it that way."

    This patch is trying to realize these ideas.

    Signed-off-by: Jarek Poplawski
    Signed-off-by: David S. Miller

    Jarek Poplawski
     

20 Jul, 2008

2 commits

09 Jul, 2008

2 commits

  • 5ce2d488f   pkt_sched: Remove 'dev' member of struct Qdisc. ... Browse Code »

    It can be obtained via the netdev_queue. So create a helper routine,
    qdisc_dev(), to make the transformations nicer looking.

    Now, qdisc_alloc() now no longer needs a net_device pointer argument.

    Signed-off-by: David S. Miller

    David S. Miller
     
  • bb949fbd1   netdev: Create netdev_queue abstraction. ... Browse Code »

    A netdev_queue is an entity managed by a qdisc.

    Currently there is one RX and one TX queue, and a netdev_queue merely
    contains a backpointer to the net_device.

    The Qdisc struct is augmented with a netdev_queue pointer as well.

    Eventually the 'dev' Qdisc member will go away and we will have the
    resulting hierarchy:

    net_device --> netdev_queue --> Qdisc

    Also, qdisc_alloc() and qdisc_create_dflt() now take a netdev_queue
    pointer argument.

    Signed-off-by: David S. Miller

    David S. Miller
     

02 Jul, 2008

1 commit

04 Jun, 2008

1 commit

  • bc3ed28ca   netlink: Improve returned error codes ... Browse Code »

    Make nlmsg_trim(), nlmsg_cancel(), genlmsg_cancel(), and
    nla_nest_cancel() void functions.

    Return -EMSGSIZE instead of -1 if the provided message buffer is not
    big enough.

    Signed-off-by: Thomas Graf
    Signed-off-by: David S. Miller

    Thomas Graf
     

29 Jan, 2008

7 commits