• Paul E. McKenney's avatar
    rcu: limit rcu_node leaf-level fanout · 0209f649
    Paul E. McKenney authored
    Some recent benchmarks have indicated possible lock contention on the
    leaf-level rcu_node locks.  This commit therefore limits the number of
    CPUs per leaf-level rcu_node structure to 16, in other words, there
    can be at most 16 rcu_data structures fanning into a given rcu_node
    structure.  Prior to this, the limit was 32 on 32-bit systems and 64 on
    64-bit systems.
    
    Note that the fanout of non-leaf rcu_node structures is unchanged.  The
    organization of accesses to the rcu_node tree is such that references
    to non-leaf rcu_node structures are much less frequent than to the
    leaf structures.
    Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
    0209f649
rcutree.h 15.4 KB