Re: [PATCH tip/core/rcu 2/2] rcu: Trace callback acceleration
You probably don't want to use --chain-reply-to; that makes patch N a reply to patch N-1 rather than to the cover letter, which creates much deeper and harder to follow threads. - Josh Triplett -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH tip/core/rcu 2/2] rcu: Trace callback acceleration
You probably don't want to use --chain-reply-to; that makes patch N a reply to patch N-1 rather than to the cover letter, which creates much deeper and harder to follow threads. - Josh Triplett -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH tip/core/rcu 2/2] rcu: Trace callback acceleration
From: "Paul E. McKenney"
This commit adds event tracing for callback acceleration to allow better
tracking of callbacks through the system.
Signed-off-by: Paul E. McKenney
---
include/trace/events/rcu.h |6 --
kernel/rcutree.c |6 ++
2 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h
index d4f559b..5678114 100644
--- a/include/trace/events/rcu.h
+++ b/include/trace/events/rcu.h
@@ -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,
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index ac6a75d..e9dce4f 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -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");
}
/*
--
1.7.8
--
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[PATCH tip/core/rcu 2/2] rcu: Trace callback acceleration
From: Paul E. McKenney paul...@linux.vnet.ibm.com This commit adds event tracing for callback acceleration to allow better tracking of callbacks through the system. Signed-off-by: Paul E. McKenney paul...@linux.vnet.ibm.com --- include/trace/events/rcu.h |6 -- kernel/rcutree.c |6 ++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index d4f559b..5678114 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -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, diff --git a/kernel/rcutree.c b/kernel/rcutree.c index ac6a75d..e9dce4f 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -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); } /* -- 1.7.8 -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
