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author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-05-22 02:41:36 -0700 |
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committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-06-10 13:37:10 -0700 |
commit | d62840995a99c9766803d54e9d7923f247a1c1db (patch) | |
tree | d278186c5541f3294a263edc19a15b4e1809cb06 | |
parent | 317ddd256b9c24b0d78fa8018f80f1e495481a10 (diff) | |
download | talos-obmc-linux-d62840995a99c9766803d54e9d7923f247a1c1db.tar.gz talos-obmc-linux-d62840995a99c9766803d54e9d7923f247a1c1db.zip |
trace: Allow idle-safe tracepoints to be called from irq
__DECLARE_TRACE_RCU() currently creates an _rcuidle() tracepoint which
may safely be invoked from what RCU considers to be an idle CPU.
However, these _rcuidle() tracepoints may -not- be invoked from the
handler of an irq taken from idle, because rcu_idle_enter() zeroes
RCU's nesting-level counter, so that the rcu_irq_exit() returning to
idle will trigger a WARN_ON_ONCE().
This commit therefore substitutes rcu_irq_enter() for rcu_idle_exit()
and rcu_irq_exit() for rcu_idle_enter() in order to make the _rcuidle()
tracepoints usable from irq handlers as well as from process context.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
-rw-r--r-- | include/linux/tracepoint.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 2f322c38bd4d..f8e084d0fc77 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -145,8 +145,8 @@ static inline void tracepoint_synchronize_unregister(void) TP_PROTO(data_proto), \ TP_ARGS(data_args), \ TP_CONDITION(cond), \ - rcu_idle_exit(), \ - rcu_idle_enter()); \ + rcu_irq_enter(), \ + rcu_irq_exit()); \ } #else #define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) |