Merge branch 'md-fixes' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md...

[linux-2.6-microblaze.git] / kernel / Kconfig.preempt

diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
index 4160173..bd7c414 100644 (file)
--- a/kernel/Kconfig.preempt
+++ b/kernel/Kconfig.preempt
@@ -99,3 +99,23 @@ config PREEMPT_DYNAMIC
 
          Interesting if you want the same pre-built kernel should be used for
          both Server and Desktop workloads.
+
+config SCHED_CORE
+       bool "Core Scheduling for SMT"
+       default y
+       depends on SCHED_SMT
+       help
+         This option permits Core Scheduling, a means of coordinated task
+         selection across SMT siblings. When enabled -- see
+         prctl(PR_SCHED_CORE) -- task selection ensures that all SMT siblings
+         will execute a task from the same 'core group', forcing idle when no
+         matching task is found.
+
+         Use of this feature includes:
+          - mitigation of some (not all) SMT side channels;
+          - limiting SMT interference to improve determinism and/or performance.
+
+         SCHED_CORE is default enabled when SCHED_SMT is enabled -- when
+         unused there should be no impact on performance.
+
+