• Paul E. McKenney's avatar
    rcu: Remove single-rcu_node optimization in rcu_start_gp() · f38bd102
    Paul E. McKenney authored
    The grace-period initialization sequence in rcu_start_gp() has a special
    case for systems where the rcu_node tree is a single rcu_node structure.
    This made sense some years ago when systems were smaller and up to 64
    CPUs could share a single rcu_node structure, but now that large systems
    are common and a given leaf rcu_node structure can support only 16 CPUs
    (due to lock contention on the rcu_node's ->lock field), this optimization
    is almost never taken.  And even the small mobile platforms that might
    make use of it might rather have the kernel text reduction.
    
    Therefore, this commit removes the check for single-rcu_node trees.
    Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
    Reviewed-by: default avatarJosh Triplett <josh@joshtriplett.org>
    f38bd102
rcutree.c 71.1 KB