lkml.org 
[lkml]   [2010]   [Dec]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[171/289] latencytop: fix per task accumulator
    2.6.36-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Ken Chen <kenchen@google.com>

    commit 38715258aa2e8cd94bd4aafadc544e5104efd551 upstream.

    Per task latencytop accumulator prematurely terminates due to erroneous
    placement of latency_record_count. It should be incremented whenever a
    new record is allocated instead of increment on every latencytop event.

    Also fix search iterator to only search known record events instead of
    blindly searching all pre-allocated space.

    Signed-off-by: Ken Chen <kenchen@google.com>
    Reviewed-by: Arjan van de Ven <arjan@infradead.org>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    kernel/latencytop.c | 17 ++++++++---------
    1 file changed, 8 insertions(+), 9 deletions(-)

    --- a/kernel/latencytop.c
    +++ b/kernel/latencytop.c
    @@ -194,14 +194,7 @@ __account_scheduler_latency(struct task_

    account_global_scheduler_latency(tsk, &lat);

    - /*
    - * short term hack; if we're > 32 we stop; future we recycle:
    - */
    - tsk->latency_record_count++;
    - if (tsk->latency_record_count >= LT_SAVECOUNT)
    - goto out_unlock;
    -
    - for (i = 0; i < LT_SAVECOUNT; i++) {
    + for (i = 0; i < tsk->latency_record_count; i++) {
    struct latency_record *mylat;
    int same = 1;

    @@ -227,8 +220,14 @@ __account_scheduler_latency(struct task_
    }
    }

    + /*
    + * short term hack; if we're > 32 we stop; future we recycle:
    + */
    + if (tsk->latency_record_count >= LT_SAVECOUNT)
    + goto out_unlock;
    +
    /* Allocated a new one: */
    - i = tsk->latency_record_count;
    + i = tsk->latency_record_count++;
    memcpy(&tsk->latency_record[i], &lat, sizeof(struct latency_record));

    out_unlock:



    \
     
     \ /
      Last update: 2010-12-08 02:11    [W:0.020 / U:1.352 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site