Messages in this thread | | | Date | Fri, 19 Aug 2011 11:01:37 -0700 | From | Greg KH <> | Subject | Re: [stable] [PATCH RFC tip/core/urgent] rcu: Avoid having just-onlined CPU resched itself when RCU is idle |
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On Fri, Aug 19, 2011 at 09:35:47AM -0700, Paul E. McKenney wrote: > CPUs set rdp->qs_pending when coming online to resolve races with > grace-period start. However, this means that if RCU is idle, the > just-onlined CPU might needlessly send itself resched IPIs. Adjust the > online-CPU initialization to avoid this, and also to correctly cause > the CPU to respond to the current grace period if needed. > > This patch is believed to fix or otherwise suppress problems in > https://bugzilla.redhat.com/show_bug.cgi?id=726877, however, the > relationship is not apparent to this patch's author. That said, it is > hard to argue with test results. > > This will be available from -rcu as soon as kernel.org's mirrors update: > > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu.git rcu/urgent > > Reported-by: Nicolas Mailhot <nicolas.mailhot@laposte.net> > Reported-by: Michal Jaegermann <michal@harddata.com> > Reported-by: Josh Boyer <jwboyer@redhat.com> > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > Tested-by: Josh Boyer <jwboyer@redhat.com> > > rcutree.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) >
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This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read Documentation/stable_kernel_rules.txt for how to do this properly.
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