The patch titled
markers: use synchronize_sched()
has been added to the -mm tree. Its filename is
markers-use-synchronize_sched.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: markers: use synchronize_sched()
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx>
Use synchronize_sched before calling call_rcu in CONFIG_PREEMPT_RCU until we
have call_rcu_sched and rcu_barrier_sched in mainline. It will slow down the
marker operations in CONFIG_PREEMPT_RCU, but it fixes the current race against
the preempt_disable/enable() protected code paths.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/marker.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff -puN kernel/marker.c~markers-use-synchronize_sched kernel/marker.c
--- a/kernel/marker.c~markers-use-synchronize_sched
+++ a/kernel/marker.c
@@ -671,6 +671,9 @@ int marker_probe_register(const char *na
entry->rcu_pending = 1;
/* write rcu_pending before calling the RCU callback */
smp_wmb();
+#ifdef CONFIG_PREEMPT_RCU
+ synchronize_sched(); /* Until we have the call_rcu_sched() */
+#endif
call_rcu(&entry->rcu, free_old_closure);
end:
mutex_unlock(&markers_mutex);
@@ -714,6 +717,9 @@ int marker_probe_unregister(const char *
entry->rcu_pending = 1;
/* write rcu_pending before calling the RCU callback */
smp_wmb();
+#ifdef CONFIG_PREEMPT_RCU
+ synchronize_sched(); /* Until we have the call_rcu_sched() */
+#endif
call_rcu(&entry->rcu, free_old_closure);
remove_marker(name); /* Ignore busy error message */
ret = 0;
@@ -792,6 +798,9 @@ int marker_probe_unregister_private_data
entry->rcu_pending = 1;
/* write rcu_pending before calling the RCU callback */
smp_wmb();
+#ifdef CONFIG_PREEMPT_RCU
+ synchronize_sched(); /* Until we have the call_rcu_sched() */
+#endif
call_rcu(&entry->rcu, free_old_closure);
remove_marker(entry->name); /* Ignore busy error message */
end:
_
Patches currently in -mm which might be from mathieu.desnoyers@xxxxxxxxxx are
markers-use-synchronize_sched.patch
make-marker_debug-static.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
