mm: numa: Add fault driven placement and migration

NOTE: This patch is based on "sched, numa, mm: Add fault driven
	placement and migration policy" but as it throws away all the policy
	to just leave a basic foundation I had to drop the signed-offs-by.

This patch creates a bare-bones method for setting PTEs pte_numa in the
context of the scheduler that when faulted later will be faulted onto the
node the CPU is running on.  In itself this does nothing useful but any
placement policy will fundamentally depend on receiving hints on placement
from fault context and doing something intelligent about it.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>

1 files changed, 22 insertions, 2 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 26f65eaa01f9..025e1ae50ef1 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -256,9 +256,11 @@ static int min_sched_granularity_ns = 100000;		/* 100 usecs */
 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
+#ifdef CONFIG_SMP
 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
-#endif
+#endif /* CONFIG_SMP */
+#endif /* CONFIG_SCHED_DEBUG */
 
 #ifdef CONFIG_COMPACTION
 static int min_extfrag_threshold;
@@ -301,6 +303,7 @@ static struct ctl_table kern_table[] = {
                 .extra1         = &min_wakeup_granularity_ns,
                 .extra2         = &max_wakeup_granularity_ns,
         },
+#ifdef CONFIG_SMP
         {
                 .procname       = "sched_tunable_scaling",
                 .data           = &sysctl_sched_tunable_scaling,
@@ -347,7 +350,24 @@ static struct ctl_table kern_table[] = {
                 .extra1         = &zero,
                 .extra2         = &one,
         },
-#endif
+#endif /* CONFIG_SMP */
+#ifdef CONFIG_NUMA_BALANCING
+        {
+                .procname       = "numa_balancing_scan_period_min_ms",
+                .data           = &sysctl_numa_balancing_scan_period_min,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = proc_dointvec,
+        },
+        {
+                .procname       = "numa_balancing_scan_period_max_ms",
+                .data           = &sysctl_numa_balancing_scan_period_max,
+                .maxlen         = sizeof(unsigned int),
+                .mode           = 0644,
+                .proc_handler   = proc_dointvec,
+        },
+#endif /* CONFIG_NUMA_BALANCING */
+#endif /* CONFIG_SCHED_DEBUG */
         {
                 .procname       = "sched_rt_period_us",
                 .data           = &sysctl_sched_rt_period,