x86/sched: Add SD_ASYM_PACKING flags to x86 ITMT CPU

Some Intel cores in a package can be boosted to a higher turbo frequency
with ITMT 3.0 technology. The scheduler can use the asymmetric packing
feature to move tasks to the more capable cores.

If ITMT is enabled, add SD_ASYM_PACKING flag to the thread and core
sched domains to enable asymmetric packing.

Co-developed-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: linux-pm@vger.kernel.org
Cc: peterz@infradead.org
Cc: jolsa@redhat.com
Cc: rjw@rjwysocki.net
Cc: linux-acpi@vger.kernel.org
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/9bbb885bedbef4eb50e197305eb16b160cff0831.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 24 insertions, 4 deletions

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ac61ee71d50e..4f130624c3f4 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -482,22 +482,42 @@ static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
         return false;
 }
 
+#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC)
+static inline int x86_sched_itmt_flags(void)
+{
+        return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
+}
+
+#ifdef CONFIG_SCHED_MC
+static int x86_core_flags(void)
+{
+        return cpu_core_flags() | x86_sched_itmt_flags();
+}
+#endif
+#ifdef CONFIG_SCHED_SMT
+static int x86_smt_flags(void)
+{
+        return cpu_smt_flags() | x86_sched_itmt_flags();
+}
+#endif
+#endif
+
 static struct sched_domain_topology_level x86_numa_in_package_topology[] = {
 #ifdef CONFIG_SCHED_SMT
-        { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+        { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
 #endif
 #ifdef CONFIG_SCHED_MC
-        { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
+        { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
 #endif
         { NULL, },
 };
 
 static struct sched_domain_topology_level x86_topology[] = {
 #ifdef CONFIG_SCHED_SMT
-        { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+        { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
 #endif
 #ifdef CONFIG_SCHED_MC
-        { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
+        { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
 #endif
         { cpu_cpu_mask, SD_INIT_NAME(DIE) },
         { NULL, },