diff options
| author | Ingo Molnar <mingo@kernel.org> | 2012-09-27 08:09:38 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2012-09-27 08:09:38 +0200 |
| commit | fa34da708cbe1e2d9a2ee7fc68ea8fccbf095d12 (patch) | |
| tree | b20795decb064af75aae8f9f6af77806b1a4769a /init | |
| parent | a9b86fab4b0a36fc4cd2712a07259c2c0e769742 (diff) | |
| parent | cb349ca95407cbc11424d5e9fc7c8e700709041b (diff) | |
Merge branch 'rcu/idle' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull the RCU adaptive-idle feature from Paul E. McKenney:
"This series adds RCU APIs that allow non-idle tasks to
enter RCU idle mode and provides x86 code to make use of them, allowing
RCU to treat user-mode execution as an extended quiescent state when the
new RCU_USER_QS kernel configuration parameter is specified. Work is
in progress to port this to a few other architectures, but is not part
of this series."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'init')
| -rw-r--r-- | init/Kconfig | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig index af6c7f8ba019..c26b8a1d2b57 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -441,6 +441,24 @@ config PREEMPT_RCU This option enables preemptible-RCU code that is common between the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations. +config RCU_USER_QS + bool "Consider userspace as in RCU extended quiescent state" + depends on HAVE_RCU_USER_QS && SMP + help + This option sets hooks on kernel / userspace boundaries and + puts RCU in extended quiescent state when the CPU runs in + userspace. It means that when a CPU runs in userspace, it is + excluded from the global RCU state machine and thus doesn't + to keep the timer tick on for RCU. + +config RCU_USER_QS_FORCE + bool "Force userspace extended QS by default" + depends on RCU_USER_QS + help + Set the hooks in user/kernel boundaries by default in order to + test this feature that treats userspace as an extended quiescent + state until we have a real user like a full adaptive nohz option. + config RCU_FANOUT int "Tree-based hierarchical RCU fanout value" range 2 64 if 64BIT |