On Fri, 22 Aug 2008, Steven Rostedt wrote: > > > On Sat, 23 Aug 2008, John Kacur wrote: > > > > One more patch that was missed - it was discussed here > > http://marc.info/?l=linux-rt-users&m=121846031913931&w=2 > > > > I am resending it, please consider for -rt4. > > Without it I continue to get the following type of message. > > > > Actually this was left out intentionally. The quick fix would be the one > that Gregory Haskins suggested about not reporting when the task is bound > to one CPU. This bothers me a little, but is probably OK for now. A task > can still migrate from one cpu to another by the user, and this can cause > havic if a smp_processor_id is used. > > I needed to examine this a bit closer before coming up with a proper fix. This patch below should be sufficient. I just changed your local_irqs_save to preempt_disabled: I have this queued for -rt4, but that is where I also plan on adding the latest ftrace updates so it may take a bit to get it out. -- Steve ======= From: Steven Rostedt <srostedt@xxxxxxxxxx> Subject: suppress warning of smp_processor_id use. John Kacur pointed out that the get_cpu_var used in net/sched/sch_generic.c would trigger warnings. This was happing on a statistic variable and by a softirq which is bound to a single thread. John sent a patch that used local_irq_save which is a little bit of overkill. This version uses preempt disable, but we still need to create a preempt_disable_rt API that is only activated when PREEMPT_RT is configured. Signed-off-by: Steven Rostedt <srostedt@xxxxxxxxxx> --- net/sched/sch_generic.c | 2 ++ 1 file changed, 2 insertions(+) Index: linux-2.6.26.3-rt3/net/sched/sch_generic.c =================================================================== --- linux-2.6.26.3-rt3.orig/net/sched/sch_generic.c 2008-08-22 21:28:50.000000000 -0400 +++ linux-2.6.26.3-rt3/net/sched/sch_generic.c 2008-08-22 21:29:38.000000000 -0400 @@ -112,7 +112,9 @@ static inline int handle_dev_cpu_collisi * Another cpu is holding lock, requeue & delay xmits for * some time. */ + preempt_disable(); /* FIXME: we need an _rt version of this */ __get_cpu_var(netdev_rx_stat).cpu_collision++; + preempt_enable(); ret = dev_requeue_skb(skb, dev, q); } -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
