• Paul E. McKenney's avatar
    rcu: Make non-preemptive schedule be Tasks RCU quiescent state · bcbfdd01
    Paul E. McKenney authored
    Currently, a call to schedule() acts as a Tasks RCU quiescent state
    only if a context switch actually takes place.  However, just the
    call to schedule() guarantees that the calling task has moved off of
    whatever tracing trampoline that it might have been one previously.
    This commit therefore plumbs schedule()'s "preempt" parameter into
    rcu_note_context_switch(), which then records the Tasks RCU quiescent
    state, but only if this call to schedule() was -not- due to a preemption.
    
    To avoid adding overhead to the common-case context-switch path,
    this commit hides the rcu_note_context_switch() check under an existing
    non-common-case check.
    Suggested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
    bcbfdd01
update.c 28.7 KB