Commit-ID: d677124b1fc3b2706a13e92f1b329f1ac77e5f20 Gitweb: http://git.kernel.org/tip/d677124b1fc3b2706a13e92f1b329f1ac77e5f20 Author: Frederic Weisbecker <fweisbec@xxxxxxxxx> AuthorDate: Thu, 11 Oct 2012 01:48:28 +0200 Committer: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> CommitDate: Wed, 10 Oct 2012 17:35:01 -0700 rcu: Advise most users not to enable RCU user mode Discourage distros from enabling CONFIG_RCU_USER_QS because it brings overhead for no benefits yet. It's not a useful feature on its own until we can fully run an adaptive tickless kernel. Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> --- init/Kconfig | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index c26b8a1..89093e1 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -451,6 +451,12 @@ config RCU_USER_QS excluded from the global RCU state machine and thus doesn't to keep the timer tick on for RCU. + Unless you want to hack and help the development of the full + tickless feature, you shouldn't enable this option. It adds + unnecessary overhead. + + If unsure say N + config RCU_USER_QS_FORCE bool "Force userspace extended QS by default" depends on RCU_USER_QS @@ -459,6 +465,12 @@ config RCU_USER_QS_FORCE test this feature that treats userspace as an extended quiescent state until we have a real user like a full adaptive nohz option. + Unless you want to hack and help the development of the full + tickless feature, you shouldn't enable this option. It adds + unnecessary overhead. + + If unsure say N + config RCU_FANOUT int "Tree-based hierarchical RCU fanout value" range 2 64 if 64BIT -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
|