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Subject[PATCH RT] sched: let softirq_count() return !0 if inside local_bh_disable()ed section
I don't see a reason why softirq_count() shouldn't reflect the fact that
we are within a local_bh_disable() section. I *think* it was done
primary because in RT the softirq is slightly different (and
preemptible) and it broke some of RCU's assumptions.
I don't see any fallout with this change. Furthermore, all checks like
"WARN_ON(!softirq_count())" will work and we can drop the workaround we
currently have in the queue.

Signed-off-by: Sebastian Andrzej Siewior <>
include/linux/preempt.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 0591df500e9d..d8c05a2626ca 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -91,7 +91,7 @@
# define softirq_count() (preempt_count() & SOFTIRQ_MASK)
# define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
-# define softirq_count() (0UL)
+# define softirq_count() (current->softirq_nestcnt)
extern int in_serving_softirq(void);

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