Commit 6d4b418c authored Nov 27, 2012 by Paul E. McKenney

rcu: Trace callback acceleration



This commit adds event tracing for callback acceleration to allow better
tracking of callbacks through the system.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

parent dc35c893

include/trace/events/rcu.h

+4 −2

Original line number	Diff line number	Diff line
		@@ -44,8 +44,10 @@ TRACE_EVENT(rcu_utilization,
		* of a new grace period or the end of an old grace period ("cpustart"
		* and "cpuend", respectively), a CPU passing through a quiescent
		* state ("cpuqs"), a CPU coming online or going offline ("cpuonl"
		* and "cpuofl", respectively), and a CPU being kicked for being too
		* long in dyntick-idle mode ("kick").
		* and "cpuofl", respectively), a CPU being kicked for being too
		* long in dyntick-idle mode ("kick"), a CPU accelerating its new
		* callbacks to RCU_NEXT_READY_TAIL ("AccReadyCB"), and a CPU
		* accelerating its new callbacks to RCU_WAIT_TAIL ("AccWaitCB").
		*/
		TRACE_EVENT(rcu_grace_period,

kernel/rcutree.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -1168,6 +1168,12 @@ static void rcu_accelerate_cbs(struct rcu_state rsp, struct rcu_node rnp,
		rdp->nxttail[i] = rdp->nxttail[RCU_NEXT_TAIL];
		rdp->nxtcompleted[i] = c;
		}

		/* Trace depending on how much we were able to accelerate. */
		if (!*rdp->nxttail[RCU_WAIT_TAIL])
		trace_rcu_grace_period(rsp->name, rdp->gpnum, "AccWaitCB");
		else
		trace_rcu_grace_period(rsp->name, rdp->gpnum, "AccReadyCB");
		}

		/*