diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 08:10:07 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 08:10:07 -0700 |
| commit | 016aa2ed1cc9cf704cf76d8df07751b6daa9750f (patch) | |
| tree | bebfea796fbcaed6995f41cb4ab1333a0e09a1ff /kernel/rcupdate.c | |
| parent | 34d211a2d5df4984a35b18d8ccacbe1d10abb067 (diff) | |
| parent | 241e6663b5151733294d1a230a3fd8a4d32e187f (diff) | |
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
smp: Document transitivity for memory barriers.
rcu: add comment saying why DEBUG_OBJECTS_RCU_HEAD depends on PREEMPT.
rcupdate: remove dead code
rcu: add documentation saying which RCU flavor to choose
rcutorture: Get rid of duplicate sched.h include
rcu: call __rcu_read_unlock() in exit_rcu for tiny RCU
Diffstat (limited to 'kernel/rcupdate.c')
| -rw-r--r-- | kernel/rcupdate.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index a23a57a976d..f3240e98792 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -214,11 +214,12 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state) * Ensure that queued callbacks are all executed. * If we detect that we are nested in a RCU read-side critical * section, we should simply fail, otherwise we would deadlock. + * Note that the machinery to reliably determine whether + * or not we are in an RCU read-side critical section + * exists only in the preemptible RCU implementations + * (TINY_PREEMPT_RCU and TREE_PREEMPT_RCU), which is why + * DEBUG_OBJECTS_RCU_HEAD is disallowed if !PREEMPT. */ -#ifndef CONFIG_PREEMPT - WARN_ON(1); - return 0; -#else if (rcu_preempt_depth() != 0 || preempt_count() != 0 || irqs_disabled()) { WARN_ON(1); @@ -229,7 +230,6 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state) rcu_barrier_bh(); debug_object_free(head, &rcuhead_debug_descr); return 1; -#endif default: return 0; } |