From 52494535103986dbbf689b44d8c2c7efe2132b16 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 14 Nov 2012 16:26:40 -0800 Subject: 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 Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett [ paulmck: Add fix to build problem located by Randy Dunlap based on diagnosis by Steven Rostedt. ] --- include/linux/rcupdate.h | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'include/linux/rcupdate.h') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 275aa3f1062d..7f89cea596e1 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -53,7 +53,10 @@ extern int rcutorture_runnable; /* for sysctl */ extern void rcutorture_record_test_transition(void); extern void rcutorture_record_progress(unsigned long vernum); extern void do_trace_rcu_torture_read(char *rcutorturename, - struct rcu_head *rhp); + struct rcu_head *rhp, + unsigned long secs, + unsigned long c_old, + unsigned long c); #else static inline void rcutorture_record_test_transition(void) { @@ -63,9 +66,13 @@ static inline void rcutorture_record_progress(unsigned long vernum) } #ifdef CONFIG_RCU_TRACE extern void do_trace_rcu_torture_read(char *rcutorturename, - struct rcu_head *rhp); + struct rcu_head *rhp, + unsigned long secs, + unsigned long c_old, + unsigned long c); #else -#define do_trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) +#define do_trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \ + do { } while (0) #endif #endif -- cgit v1.2.3 From 90f45e4e729a7ffaa3ed2423834aad612870b427 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 10 Jan 2013 05:24:49 -0800 Subject: rcu: Remove obsolete Kconfig option from comment Signed-off-by: Paul E. McKenney --- include/linux/rcupdate.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/rcupdate.h') diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 275aa3f1062d..7e12dbaa1457 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -749,7 +749,7 @@ static inline void rcu_preempt_sleep_check(void) * preemptible RCU implementations (TREE_PREEMPT_RCU and TINY_PREEMPT_RCU) * in CONFIG_PREEMPT kernel builds, RCU read-side critical sections may * be preempted, but explicit blocking is illegal. Finally, in preemptible - * RCU implementations in real-time (CONFIG_PREEMPT_RT) kernel builds, + * RCU implementations in real-time (with -rt patchset) kernel builds, * RCU read-side critical sections may be preempted and they may also * block, but only when acquiring spinlocks that are subject to priority * inheritance. -- cgit v1.2.3