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
     

05 Jun, 2017

1 commit

  • fbd0ac604   net-procfs: Use vsnprintf extension %phN ... Browse Code »

    Save a bit of code by using the kernel extension.

    $ size net/core/net-procfs.o*
    text data bss dec hex filename
    3701 120 0 3821 eed net/core/net-procfs.o.new
    3764 120 0 3884 f2c net/core/net-procfs.o.old

    Signed-off-by: Joe Perches
    Signed-off-by: David S. Miller

    Joe Perches
     

27 Apr, 2016

1 commit

21 May, 2013

1 commit

  • 99bbc7074   rps: selective flow shedding during softnet overflow ... Browse Code »

    A cpu executing the network receive path sheds packets when its input
    queue grows to netdev_max_backlog. A single high rate flow (such as a
    spoofed source DoS) can exceed a single cpu processing rate and will
    degrade throughput of other flows hashed onto the same cpu.

    This patch adds a more fine grained hashtable. If the netdev backlog
    is above a threshold, IRQ cpus track the ratio of total traffic of
    each flow (using 4096 buckets, configurable). The ratio is measured
    by counting the number of packets per flow over the last 256 packets
    from the source cpu. Any flow that occupies a large fraction of this
    (set at 50%) will see packet drop while above the threshold.

    Tested:
    Setup is a muli-threaded UDP echo server with network rx IRQ on cpu0,
    kernel receive (RPS) on cpu0 and application threads on cpus 2--7
    each handling 20k req/s. Throughput halves when hit with a 400 kpps
    antagonist storm. With this patch applied, antagonist overload is
    dropped and the server processes its complete load.

    The patch is effective when kernel receive processing is the
    bottleneck. The above RPS scenario is a extreme, but the same is
    reached with RFS and sufficient kernel processing (iptables, packet
    socket tap, ..).

    Signed-off-by: Willem de Bruijn
    Acked-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Willem de Bruijn
     

26 Mar, 2013

1 commit

28 Feb, 2013

1 commit

  • b67bfe0d4   hlist: drop the node parameter from iterators ... Browse Code »

    I'm not sure why, but the hlist for each entry iterators were conceived

    list_for_each_entry(pos, head, member)

    The hlist ones were greedy and wanted an extra parameter:

    hlist_for_each_entry(tpos, pos, head, member)

    Why did they need an extra pos parameter? I'm not quite sure. Not only
    they don't really need it, it also prevents the iterator from looking
    exactly like the list iterator, which is unfortunate.

    Besides the semantic patch, there was some manual work required:

    - Fix up the actual hlist iterators in linux/list.h
    - Fix up the declaration of other iterators based on the hlist ones.
    - A very small amount of places were using the 'node' parameter, this
    was modified to use 'obj->member' instead.
    - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
    properly, so those had to be fixed up manually.

    The semantic patch which is mostly the work of Peter Senna Tschudin is here:

    @@
    iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

    type T;
    expression a,c,d,e;
    identifier b;
    statement S;
    @@

    -T b;

    [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
    [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
    [akpm@linux-foundation.org: checkpatch fixes]
    [akpm@linux-foundation.org: fix warnings]
    [akpm@linux-foudnation.org: redo intrusive kvm changes]
    Tested-by: Peter Senna Tschudin
    Acked-by: Paul E. McKenney
    Signed-off-by: Sasha Levin
    Cc: Wu Fengguang
    Cc: Marcelo Tosatti
    Cc: Gleb Natapov
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Sasha Levin
     

20 Feb, 2013

1 commit

19 Feb, 2013

1 commit