2 files changed, 91 insertions, 24 deletions

diff --git a/init/Kconfig b/init/Kconfig
index 6fdd6e339326..1a207efca591 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -486,35 +486,35 @@ config PREEMPT_RCU
           This option enables preemptible-RCU code that is common between
           the TREE_PREEMPT_RCU and TINY_PREEMPT_RCU implementations.
 
+config CONTEXT_TRACKING
+       bool
+
 config RCU_USER_QS
         bool "Consider userspace as in RCU extended quiescent state"
-        depends on HAVE_RCU_USER_QS && SMP
+        depends on HAVE_CONTEXT_TRACKING && SMP
+        select CONTEXT_TRACKING
         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.
+          try 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.
+          dynticks mode, you shouldn't enable this option.  It also
+          adds unnecessary overhead.
 
           If unsure say N
 
-config RCU_USER_QS_FORCE
-        bool "Force userspace extended QS by default"
-        depends on RCU_USER_QS
+config CONTEXT_TRACKING_FORCE
+        bool "Force context tracking"
+        depends on CONTEXT_TRACKING
         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.
-
-          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
+          Probe on user/kernel boundaries by default in order to
+          test the features that rely on it such as userspace RCU extended
+          quiescent states.
+          This test is there for debugging until we have a real user like the
+          full dynticks mode.
 
 config RCU_FANOUT
         int "Tree-based hierarchical RCU fanout value"
@@ -582,14 +582,13 @@ config RCU_FAST_NO_HZ
         depends on NO_HZ && SMP
         default n
         help
-          This option causes RCU to attempt to accelerate grace periods
-          in order to allow CPUs to enter dynticks-idle state more
-          quickly.  On the other hand, this option increases the overhead
-          of the dynticks-idle checking, particularly on systems with
-          large numbers of CPUs.
+          This option causes RCU to attempt to accelerate grace periods in
+          order to allow CPUs to enter dynticks-idle state more quickly.
+          On the other hand, this option increases the overhead of the
+          dynticks-idle checking, thus degrading scheduling latency.
 
-          Say Y if energy efficiency is critically important, particularly
-                if you have relatively few CPUs.
+          Say Y if energy efficiency is critically important, and you don't
+                care about real-time response.
 
           Say N if you are unsure.
 
@@ -655,6 +654,28 @@ config RCU_BOOST_DELAY
 
           Accept the default if unsure.
 
+config RCU_NOCB_CPU
+        bool "Offload RCU callback processing from boot-selected CPUs"
+        depends on TREE_RCU || TREE_PREEMPT_RCU
+        default n
+        help
+          Use this option to reduce OS jitter for aggressive HPC or
+          real-time workloads.  It can also be used to offload RCU
+          callback invocation to energy-efficient CPUs in battery-powered
+          asymmetric multiprocessors.
+
+          This option offloads callback invocation from the set of
+          CPUs specified at boot time by the rcu_nocbs parameter.
+          For each such CPU, a kthread ("rcuoN") will be created to
+          invoke callbacks, where the "N" is the CPU being offloaded.
+          Nothing prevents this kthread from running on the specified
+          CPUs, but (1) the kthreads may be preempted between each
+          callback, and (2) affinity or cgroups can be used to force
+          the kthreads to run on whatever set of CPUs is desired.
+
+          Say Y here if you want reduced OS jitter on selected CPUs.
+          Say N here if you are unsure.
+
 endmenu # "RCU Subsystem"
 
 config IKCONFIG
@@ -696,6 +717,50 @@ config LOG_BUF_SHIFT
 config HAVE_UNSTABLE_SCHED_CLOCK
         bool
 
+#
+# For architectures that want to enable the support for NUMA-affine scheduler
+# balancing logic:
+#
+config ARCH_SUPPORTS_NUMA_BALANCING
+        bool
+
+# For architectures that (ab)use NUMA to represent different memory regions
+# all cpu-local but of different latencies, such as SuperH.
+#
+config ARCH_WANT_NUMA_VARIABLE_LOCALITY
+        bool
+
+#
+# For architectures that are willing to define _PAGE_NUMA as _PAGE_PROTNONE
+config ARCH_WANTS_PROT_NUMA_PROT_NONE
+        bool
+
+config ARCH_USES_NUMA_PROT_NONE
+        bool
+        default y
+        depends on ARCH_WANTS_PROT_NUMA_PROT_NONE
+        depends on NUMA_BALANCING
+
+config NUMA_BALANCING_DEFAULT_ENABLED
+        bool "Automatically enable NUMA aware memory/task placement"
+        default y
+        depends on NUMA_BALANCING
+        help
+          If set, autonumic NUMA balancing will be enabled if running on a NUMA
+          machine.
+
+config NUMA_BALANCING
+        bool "Memory placement aware NUMA scheduler"
+        depends on ARCH_SUPPORTS_NUMA_BALANCING
+        depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY
+        depends on SMP && NUMA && MIGRATION
+        help
+          This option adds support for automatic NUMA aware memory/task placement.
+          The mechanism is quite primitive and is based on migrating memory when
+          it is references to the node the task is running on.
+
+          This system will be inactive on UMA systems.
+
 menuconfig CGROUPS
         boolean "Control Group support"
         depends on EVENTFD
diff --git a/init/main.c b/init/main.c
index 9cf77ab138a6..63ae904a99a8 100644
--- a/init/main.c
+++ b/init/main.c
@@ -442,9 +442,11 @@ void __init __weak smp_setup_processor_id(void)
 {
 }
 
+# if THREAD_SIZE >= PAGE_SIZE
 void __init __weak thread_info_cache_init(void)
 {
 }
+#endif
 
 /*
  * Set up kernel memory allocators
@@ -855,7 +857,7 @@ static void __init kernel_init_freeable(void)
         /*
          * init can allocate pages on any node
          */
-        set_mems_allowed(node_states[N_HIGH_MEMORY]);
+        set_mems_allowed(node_states[N_MEMORY]);
         /*
          * init can run on any cpu.
          */