Messages in this thread | | | Date | Wed, 18 Jun 2008 17:42:29 -0700 | From | Josh Triplett <> | Subject | Re: [PATCH] Make rcutorture more vicious: reinstate boot-time testing |
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Paul E. McKenney wrote: > Hello again! > > This patch re-institutes the ability to build rcutorture directly into > the Linux kernel. The reason that this capability was removed was that > this could result in your kernel being pretty much useless, as rcutorture > would be running starting from early boot. This problem has been avoided > by (1) making rcutorture run only three seconds of every six by default, > (2) adding a CONFIG_RCU_TORTURE_TEST_RUNNABLE that permits rcutorture > to be quiesced at boot time, and (3) adding a sysctl in /proc named > /proc/sys/kernel/rcutorture_runnable that permits rcutorture to be > quiesced and unquiesced when built into the kernel. > > Please note that this /proc file is -not- available when rcutorture > is built as a module. Please also note that to get the earlier > take-no-prisoners behavior, you must use the boot command line to set > rcutorture's "stutter" parameter to zero. > > The rcutorture quiescing mechanism is currently quite crude: loops > in each rcutorture process that poll a global variable once per tick. > Suggestions for improvement are welcome. The default action will > be to reduce the polling rate to a few times per second. > > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > Suggested-by: Ingo Molnar <mingo@elte.hu>
This patch looks quite reasonable to me.
Signed-off-by: Josh Triplett <josh@kernel.org>
- Josh Triplett
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