diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-08-09 21:19:29 +0200 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-09-23 18:16:14 +0200 |
| commit | 63c4db78e80407976e47bccaa2a4d8251b5a10bc (patch) | |
| tree | 31b832426eec3bf0e954440afe461b388f84e12d /include/trace | |
| parent | rcu: Flag lockless access to ->gp_flags with ACCESS_ONCE() (diff) | |
| download | linux-63c4db78e80407976e47bccaa2a4d8251b5a10bc.tar.xz linux-63c4db78e80407976e47bccaa2a4d8251b5a10bc.zip | |
rcu: Add tracing to rcu_gp_kthread()
This commit adds tracing to the rcu_gp_kthread() function in order to
help trace down hangs potentially involving this kthread.
Reported-by: Clark Williams <williams@redhat.com>
Reported-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/rcu.h | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index ee2376cfaab3..60077e12093c 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -39,15 +39,25 @@ TRACE_EVENT(rcu_utilization, #if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) /* - * Tracepoint for grace-period events: starting and ending a grace - * period ("start" and "end", respectively), a CPU noting the start - * 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), 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"). + * Tracepoint for grace-period events. Takes a string identifying the + * RCU flavor, the grace-period number, and a string identifying the + * grace-period-related event as follows: + * + * "AccReadyCB": CPU acclerates new callbacks to RCU_NEXT_READY_TAIL. + * "AccWaitCB": CPU accelerates new callbacks to RCU_WAIT_TAIL. + * "start": Start a grace period. + * "cpustart": CPU first notices a grace-period start. + * "cpuqs": CPU passes through a quiescent state. + * "cpuonl": CPU comes online. + * "cpuofl": CPU goes offline. + * "reqwait": GP kthread sleeps waiting for grace-period request. + * "reqwaitsig": GP kthread awakened by signal from reqwait state. + * "fqswait": GP kthread waiting until time to force quiescent states. + * "fqsstart": GP kthread starts forcing quiescent states. + * "fqsend": GP kthread done forcing quiescent states. + * "fqswaitsig": GP kthread awakened by signal from fqswait state. + * "end": End a grace period. + * "cpuend": CPU first notices a grace-period end. */ TRACE_EVENT(rcu_grace_period, |