lkml.org 
[lkml]   [2005]   [Sep]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Subject[PATCH] RT: Checks for cmpxchg in get_task_struct_rcu()
    From
    Date

    Adds a check for cmpxchg in get_task_struct_rcu(), and implements the
    case when it doesn't exist.

    Signed-Off-By: Daniel Walker <dwalker@mvista.com>

    Index: linux-2.6.13/include/linux/sched.h
    ===================================================================
    --- linux-2.6.13.orig/include/linux/sched.h
    +++ linux-2.6.13/include/linux/sched.h
    @@ -1026,13 +1026,21 @@ static inline int get_task_struct_rcu(st
    {
    int oldusage;

    +#ifdef __HAVE_ARCH_CMPXCHG
    do {
    oldusage = atomic_read(&t->usage);
    if (oldusage == 0) {
    return 0;
    }
    } while (cmpxchg(&t->usage.counter,
    - oldusage, oldusage + 1) != oldusage);
    + oldusage, oldusage + 1) != oldusage);
    +#else
    + oldusage = atomic_read(&t->usage);
    + if (oldusage == 0) {
    + return 0;
    + }
    + atomic_inc(&t->usage);
    +#endif
    return 1;
    }


    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-09-22 01:41    [W:0.019 / U:30.560 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site