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author | Paul E. McKenney <paul.mckenney@linaro.org> | 2012-11-15 00:26:40 (GMT) |
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committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2013-01-08 22:14:55 (GMT) |
commit | 52494535103986dbbf689b44d8c2c7efe2132b16 (patch) | |
tree | 88dd5a9d064608e9711c36f05b3b4aab8e255a4f /include/trace/events/rcu.h | |
parent | dc975e94f322e60fa8fcc44dec1820fde4de174c (diff) | |
download | linux-52494535103986dbbf689b44d8c2c7efe2132b16.tar.xz |
rcu: Reduce rcutorture tracing
Currently, rcutorture traces every read-side access. This can be
problematic because even a two-minute rcutorture run on a two-CPU system
can generate 28,853,363 reads. Normally, only a failing read is of
interest, so this commit traces adjusts rcutorture's tracing to only
trace failing reads. The resulting event tracing records the time
and the ->completed value captured at the beginning of the RCU read-side
critical section, allowing correlation with other event-tracing messages.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
[ paulmck: Add fix to build problem located by Randy Dunlap based on
diagnosis by Steven Rostedt. ]
Diffstat (limited to 'include/trace/events/rcu.h')
-rw-r--r-- | include/trace/events/rcu.h | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index d4f559b..09af021 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -523,22 +523,30 @@ TRACE_EVENT(rcu_batch_end, */ TRACE_EVENT(rcu_torture_read, - TP_PROTO(char *rcutorturename, struct rcu_head *rhp), + TP_PROTO(char *rcutorturename, struct rcu_head *rhp, + unsigned long secs, unsigned long c_old, unsigned long c), - TP_ARGS(rcutorturename, rhp), + TP_ARGS(rcutorturename, rhp, secs, c_old, c), TP_STRUCT__entry( __field(char *, rcutorturename) __field(struct rcu_head *, rhp) + __field(unsigned long, secs) + __field(unsigned long, c_old) + __field(unsigned long, c) ), TP_fast_assign( __entry->rcutorturename = rcutorturename; __entry->rhp = rhp; + __entry->secs = secs; + __entry->c_old = c_old; + __entry->c = c; ), - TP_printk("%s torture read %p", - __entry->rcutorturename, __entry->rhp) + TP_printk("%s torture read %p %luus c: %lu %lu", + __entry->rcutorturename, __entry->rhp, + __entry->secs, __entry->c_old, __entry->c) ); /* @@ -608,7 +616,8 @@ TRACE_EVENT(rcu_barrier, #define trace_rcu_invoke_kfree_callback(rcuname, rhp, offset) do { } while (0) #define trace_rcu_batch_end(rcuname, callbacks_invoked, cb, nr, iit, risk) \ do { } while (0) -#define trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) +#define trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \ + do { } while (0) #define trace_rcu_barrier(name, s, cpu, cnt, done) do { } while (0) #endif /* #else #ifdef CONFIG_RCU_TRACE */ |