On Sat, 2011-11-19 at 13:50 +0100, John Kacur wrote: > From: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > > This commit eliminates the possibility of running TREE_PREEMPT_RCU > when SMP=n and of running TINY_RCU when PREEMPT=y. People who really > want these combinations can hand-edit init/Kconfig, but eliminating > them as choices for production systems reduces the amount of testing > required. It will also allow cutting out a few #ifdefs. > > Note that running TREE_RCU and TINY_RCU on single-CPU systems using > SMP-built kernels is still supported. With this patch, I can see the need for the first patch (although there's things broken even for that), but is this really a stable fix? This looks more of an added feature than a bug fix. It's a bug fix if we consider running tree_rcu on UP a bug. Or better stated, will it break anything if we do that? -- Steve > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > > commit 8008e129dc90ff4f7a56cb033d6bd042afe3ed52 upstream > Cherry-picked for v3.0-rt and fixed-up merge conflicts > Note: This makes the depends lines for these options in init/Kconfig for v3.0-rt > match those for v3.2-rc2-rt3 > Signed-off-by: John Kacur <jkacur@xxxxxxxxxx> > --- > init/Kconfig | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/init/Kconfig b/init/Kconfig > index 89e40a4..5c1147e 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -391,7 +391,7 @@ config TREE_RCU > > config TREE_PREEMPT_RCU > bool "Preemptible tree-based hierarchical RCU" > - depends on PREEMPT > + depends on PREEMPT && SMP > help > This option selects the RCU implementation that is > designed for very large SMP systems with hundreds or > @@ -401,7 +401,7 @@ config TREE_PREEMPT_RCU > > config TINY_RCU > bool "UP-only small-memory-footprint RCU" > - depends on !SMP && !PREEMPT_RT_FULL > + depends on !PREEMPT && !SMP > help > This option selects the RCU implementation that is > designed for UP systems from which real-time response > @@ -410,7 +410,7 @@ config TINY_RCU > > config TINY_PREEMPT_RCU > bool "Preemptible UP-only small-memory-footprint RCU" > - depends on !SMP && PREEMPT && !PREEMPT_RT_FULL > + depends on PREEMPT && !SMP > help > This option selects the RCU implementation that is designed > for real-time UP systems. This option greatly reduces the -- 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
