sched/numa: Update NUMA hinting faults once per scan

[~andy/linux] / include / linux / sched.h

diff --git a/include/linux/sched.h b/include/linux/sched.h
index b1fc75e7187b55455720731ad46a67802aaecdf6..a463bc3ad4377ad69b3b58aedcfb4bd64038855b 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1343,7 +1343,20 @@ struct task_struct {
        u64 node_stamp;                 /* migration stamp  */
        struct callback_head numa_work;
 
+       /*
+        * Exponential decaying average of faults on a per-node basis.
+        * Scheduling placement decisions are made based on the these counts.
+        * The values remain static for the duration of a PTE scan
+        */
        unsigned long *numa_faults;
+
+       /*
+        * numa_faults_buffer records faults per node during the current
+        * scan window. When the scan completes, the counts in numa_faults
+        * decay and these values are copied.
+        */
+       unsigned long *numa_faults_buffer;
+
        int numa_preferred_nid;
 #endif /* CONFIG_NUMA_BALANCING */