Eric Lee / smarc-fsl-linux-kernel

02 Nov, 2017

1 commit

  • b24413180   License cleanup: add SPDX GPL-2.0 license identifier to files with no license ... Browse Code »

    Many source files in the tree are missing licensing information, which
    makes it harder for compliance tools to determine the correct license.

    By default all files without license information are under the default
    license of the kernel, which is GPL version 2.

    Update the files which contain no license information with the 'GPL-2.0'
    SPDX license identifier. The SPDX identifier is a legally binding
    shorthand, which can be used instead of the full boiler plate text.

    This patch is based on work done by Thomas Gleixner and Kate Stewart and
    Philippe Ombredanne.

    How this work was done:

    Patches were generated and checked against linux-4.14-rc6 for a subset of
    the use cases:
    - file had no licensing information it it.
    - file was a */uapi/* one with no licensing information in it,
    - file was a */uapi/* one with existing licensing information,

    Further patches will be generated in subsequent months to fix up cases
    where non-standard license headers were used, and references to license
    had to be inferred by heuristics based on keywords.

    The analysis to determine which SPDX License Identifier to be applied to
    a file was done in a spreadsheet of side by side results from of the
    output of two independent scanners (ScanCode & Windriver) producing SPDX
    tag:value files created by Philippe Ombredanne. Philippe prepared the
    base worksheet, and did an initial spot review of a few 1000 files.

    The 4.13 kernel was the starting point of the analysis with 60,537 files
    assessed. Kate Stewart did a file by file comparison of the scanner
    results in the spreadsheet to determine which SPDX license identifier(s)
    to be applied to the file. She confirmed any determination that was not
    immediately clear with lawyers working with the Linux Foundation.

    Criteria used to select files for SPDX license identifier tagging was:
    - Files considered eligible had to be source code files.
    - Make and config files were included as candidates if they contained >5
    lines of source
    - File already had some variant of a license header in it (even if
    Reviewed-by: Philippe Ombredanne
    Reviewed-by: Thomas Gleixner
    Signed-off-by: Greg Kroah-Hartman

    Greg Kroah-Hartman
     

09 Feb, 2017

1 commit

16 Nov, 2016

1 commit

  • e88a27661   gro_cells: mark napi struct as not busy poll candidates ... Browse Code »

    Rolf Neugebauer reported very long delays at netns dismantle.

    Eric W. Biederman was kind enough to look at this problem
    and noticed synchronize_net() occurring from netif_napi_del() that was
    added in linux-4.5

    Busy polling makes no sense for tunnels NAPI.
    If busy poll is used for sessions over tunnels, the poller will need to
    poll the physical device queue anyway.

    netif_tx_napi_add() could be used here, but function name is misleading,
    and renaming it is not stable material, so set NAPI_STATE_NO_BUSY_POLL
    bit directly.

    This will avoid inserting gro_cells napi structures in napi_hash[]
    and avoid the problematic synchronize_net() (per possible cpu) that
    Rolf reported.

    Fixes: 93d05d4a320c ("net: provide generic busy polling to all NAPI drivers")
    Signed-off-by: Eric Dumazet
    Reported-by: Rolf Neugebauer
    Reported-by: Eric W. Biederman
    Acked-by: Cong Wang
    Tested-by: Rolf Neugebauer
    Signed-off-by: David S. Miller

    Eric Dumazet
     

22 Jul, 2016

1 commit

01 Sep, 2015

1 commit

18 Jan, 2015

1 commit

  • 88340160f   ip_tunnel: Create percpu gro_cell ... Browse Code »

    In the ipip tunnel, the skb->queue_mapping is lost in ipip_rcv().
    All skb will be queued to the same cell->napi_skbs. The
    gro_cell_poll is pinned to one core under load. In production traffic,
    we also see severe rx_dropped in the tunl iface and it is probably due to
    this limit: skb_queue_len(&cell->napi_skbs) > netdev_max_backlog.

    This patch is trying to alloc_percpu(struct gro_cell) and schedule
    gro_cell_poll to process the skb in the same core.

    Signed-off-by: Martin KaFai Lau
    Acked-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Martin KaFai Lau
     

28 Jan, 2013

1 commit

12 Dec, 2012

1 commit

  • f8e8f97c1   net: fix a race in gro_cell_poll() ... Browse Code »

    Dmitry Kravkov reported packet drops for GRE packets since GRO support
    was added.

    There is a race in gro_cell_poll() because we call napi_complete()
    without any synchronization with a concurrent gro_cells_receive()

    Once bug was triggered, we queued packets but did not schedule NAPI
    poll.

    We can fix this issue using the spinlock protected the napi_skbs queue,
    as we have to hold it to perform skb dequeue anyway.

    As we open-code skb_dequeue(), we no longer need to mask IRQS, as both
    producer and consumer run under BH context.

    Bug added in commit c9e6bc644e (net: add gro_cells infrastructure)

    Reported-by: Dmitry Kravkov
    Signed-off-by: Eric Dumazet
    Tested-by: Dmitry Kravkov
    Signed-off-by: David S. Miller

    Eric Dumazet
     

02 Oct, 2012

1 commit

  • c9e6bc644   net: add gro_cells infrastructure ... Browse Code »

    This adds a new include file (include/net/gro_cells.h), to bring GRO
    (Generic Receive Offload) capability to tunnels, in a modular way.

    Because tunnels receive path is lockless, and GRO adds a serialization
    using a napi_struct, I chose to add an array of up to
    DEFAULT_MAX_NUM_RSS_QUEUES cells, so that multi queue devices wont be
    slowed down because of GRO layer.

    skb_get_rx_queue() is used as selector.

    In the future, we might add optional fanout capabilities, using rxhash
    for example.

    With help from Ben Hutchings who reminded me
    netif_get_num_default_rss_queues() function.

    Signed-off-by: Eric Dumazet
    Cc: Ben Hutchings
    Signed-off-by: David S. Miller

    Eric Dumazet