• Dipankar Sarma's avatar
    [PATCH] rcu: introduce call_rcu_bh() · f4d4d3f3
    Dipankar Sarma authored
    Introduces call_rcu_bh() to be used when critical sections are mostly in
    softirq context.
    
    This patch introduces a new api - call_rcu_bh().  This is to be used for RCU
    callbacks for whom the critical sections are mostly in softirq context.  These
    callbacks consider completion of a softirq handler to be a quiescent state.
    So, in order to make reader critical sections safe in process context,
    rcu_read_lock_bh() and rcu_read_unlock_bh() must be used.  Use of softirq
    handler completion as a quiescent state speeds up RCU grace periods and
    prevents too many callbacks getting queued up in softirq-heavy workloads like
    network stack.
    Signed-off-by: default avatarDipankar Sarma <dipankar@in.ibm.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    f4d4d3f3
rcupdate.c 13.2 KB