Doug / smarc-fsl-linux-kernel

06 Nov, 2013

1 commit

  • 827da44c6   net: Explicitly initialize u64_stats_sync structures for lockdep ... Browse Code »

    In order to enable lockdep on seqcount/seqlock structures, we
    must explicitly initialize any locks.

    The u64_stats_sync structure, uses a seqcount, and thus we need
    to introduce a u64_stats_init() function and use it to initialize
    the structure.

    This unfortunately adds a lot of fairly trivial initialization code
    to a number of drivers. But the benefit of ensuring correctness makes
    this worth while.

    Because these changes are required for lockdep to be enabled, and the
    changes are quite trivial, I've not yet split this patch out into 30-some
    separate patches, as I figured it would be better to get the various
    maintainers thoughts on how to best merge this change along with
    the seqcount lockdep enablement.

    Feedback would be appreciated!

    Signed-off-by: John Stultz
    Acked-by: Julian Anastasov
    Signed-off-by: Peter Zijlstra
    Cc: Alexey Kuznetsov
    Cc: "David S. Miller"
    Cc: Eric Dumazet
    Cc: Hideaki YOSHIFUJI
    Cc: James Morris
    Cc: Jesse Gross
    Cc: Mathieu Desnoyers
    Cc: "Michael S. Tsirkin"
    Cc: Mirko Lindner
    Cc: Patrick McHardy
    Cc: Roger Luethi
    Cc: Rusty Russell
    Cc: Simon Horman
    Cc: Stephen Hemminger
    Cc: Steven Rostedt
    Cc: Thomas Petazzoni
    Cc: Wensong Zhang
    Cc: netdev@vger.kernel.org
    Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org
    Signed-off-by: Ingo Molnar

    John Stultz
     

29 Nov, 2010

1 commit

  • fa9f90be7   Kill off a bunch of warning: ‘inline’ is not at beginning of declaration ... Browse Code »

    These warnings are spewed during a build of a 'allnoconfig' kernel
    (especially the ones from u64_stats_sync.h show up a lot) when building
    with -Wextra (which I often do)..
    They are
    a) annoying
    b) easy to get rid of.
    This patch kills them off.

    include/linux/u64_stats_sync.h:70:1: warning: ‘inline’ is not at beginning of declaration
    include/linux/u64_stats_sync.h:77:1: warning: ‘inline’ is not at beginning of declaration
    include/linux/u64_stats_sync.h:84:1: warning: ‘inline’ is not at beginning of declaration
    include/linux/u64_stats_sync.h:96:1: warning: ‘inline’ is not at beginning of declaration
    include/linux/u64_stats_sync.h:115:1: warning: ‘inline’ is not at beginning of declaration
    include/linux/u64_stats_sync.h:127:1: warning: ‘inline’ is not at beginning of declaration
    kernel/time.c:241:1: warning: ‘inline’ is not at beginning of declaration
    kernel/time.c:257:1: warning: ‘inline’ is not at beginning of declaration
    kernel/perf_event.c:4513:1: warning: ‘inline’ is not at beginning of declaration
    mm/page_alloc.c:4012:1: warning: ‘inline’ is not at beginning of declaration

    Signed-off-by: Jesper Juhl
    Signed-off-by: Jiri Kosina

    Jesper Juhl
     

29 Jun, 2010

2 commits

24 Jun, 2010

1 commit

  • 16b8a4761   net: Introduce u64_stats_sync infrastructure ... Browse Code »

    To properly implement 64bits network statistics on 32bit or 64bit hosts,
    we provide one new type and four methods, to ease conversions.

    Stats producer should use following template granted it already got an
    exclusive access to counters (include/linux/u64_stats_sync.h contains
    some documentation about details)

    u64_stats_update_begin(&stats->syncp);
    stats->bytes64 += len;
    stats->packets64++;
    u64_stats_update_end(&stats->syncp);

    While a consumer should use following template to get consistent
    snapshot :

    u64 tbytes, tpackets;
    unsigned int start;

    do {
    start = u64_stats_fetch_begin(&stats->syncp);
    tbytes = stats->bytes64;
    tpackets = stats->packets64;
    } while (u64_stats_fetch_retry(&stats->lock, syncp));

    Suggested by David Miller, and comments courtesy of Nick Piggin.

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

    Eric Dumazet