From: Frederic Weisbecker <fweis...@gmail.com>
Disable a vector while it is being processed. This prepare for softirq
re-entrancy with an obvious single constraint: a vector can't be
interrupted by itself.
Signed-off-by: Frederic Weisbecker <fweis...@gmail.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Sebastian Andrzej Siewior <bige...@linutronix.de>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: David S. Miller <da...@davemloft.net>
Cc: Mauro Carvalho Chehab <mche...@s-opensource.com>
Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com>
---
kernel/softirq.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 3efa59e..457bf60 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -357,7 +357,10 @@ asmlinkage __visible void __softirq_entry
__do_softirq(void)
kstat_incr_softirqs_this_cpu(vec_nr);
trace_softirq_entry(vec_nr);
+ softirq_enabled_nand(BIT(vec_nr));
+ barrier();
h->action(h);
+ softirq_enabled_or(BIT(vec_nr));
trace_softirq_exit(vec_nr);
if (unlikely(prev_count != preempt_count())) {
pr_err("huh, entered softirq %u %s %p with
preempt_count %08x, exited with %08x?\n",
--
2.7.4
