From dd9daa221e77f642954849a795fa7c59533a9b2f Mon Sep 17 00:00:00 2001 From: Oleg Nesterov <oleg@tv-sign.ru> Date: Tue, 12 Sep 2006 20:35:55 -0700 Subject: [PATCH] [PATCH] rcu_do_batch: make ->qlen decrement irq safe rcu_do_batch() decrements rdp->qlen with irqs enabled. This is not good, it can also be modified by call_rcu() from interrupt. Decrement ->qlen once with irqs disabled, after a main loop. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> --- kernel/rcupdate.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index 436ab35f6fa7..523e46483b99 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -241,12 +241,16 @@ static void rcu_do_batch(struct rcu_data *rdp) next = rdp->donelist = list->next; list->func(list); list = next; - rdp->qlen--; if (++count >= rdp->blimit) break; } + + local_irq_disable(); + rdp->qlen -= count; + local_irq_enable(); if (rdp->blimit == INT_MAX && rdp->qlen <= qlowmark) rdp->blimit = blimit; + if (!rdp->donelist) rdp->donetail = &rdp->donelist; else -- GitLab