[tip:x86/core] x86/sched: Add SD_ASYM_PACKING flags to x86 ITMT CPU

From: tip-bot for Tim Chen
Date: Thu Nov 24 2016 - 14:57:11 EST


Commit-ID: d3d37d850d1d77bd66bceb8326e6353d3314b270
Gitweb: http://git.kernel.org/tip/d3d37d850d1d77bd66bceb8326e6353d3314b270
Author: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
AuthorDate: Tue, 22 Nov 2016 12:23:57 -0800
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 24 Nov 2016 20:44:20 +0100

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@xxxxxxxxxxxxx>
Signed-off-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: peterz@xxxxxxxxxxxxx
Cc: jolsa@xxxxxxxxxx
Cc: rjw@xxxxxxxxxxxxx
Cc: linux-acpi@xxxxxxxxxxxxxxx
Cc: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
Cc: bp@xxxxxxx
Link: http://lkml.kernel.org/r/9bbb885bedbef4eb50e197305eb16b160cff0831.1479844244.git.tim.c.chen@xxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

---
arch/x86/kernel/smpboot.c | 28 ++++++++++++++++++++++++----
1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ac61ee7..4f13062 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, },