x86/topology: Define x86's arch_update_cpu_topology

The scheduler calls arch_update_cpu_topology() to check whether the
scheduler domains have to be rebuilt.

So far x86 has no requirement for this, but the upcoming ITMT support
makes this necessary.

Request the rebuild when the x86 internal update flag is set.

Suggested-by: Morten Rasmussen <morten.rasmussen@arm.com>
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/bfbf5591276ec60b2af2da798adc1060df1e2a5f.1479844244.git.tim.c.chen@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index cf75871d2f81702de799d531c2e3ad54226b5061..a5ca88a22ca3ab1e9a952d476dabefadc3196a3d 100644 (file)
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -146,4 +146,5 @@ struct pci_bus;
 int x86_pci_root_bus_node(int bus);
 void x86_pci_root_bus_resources(int bus, struct list_head *resources);
 
+extern bool x86_topology_update;
 #endif /* _ASM_X86_TOPOLOGY_H */

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 42f5eb7b4f6c85251f4ab65d6de44268b6de06ea..ac61ee71d50eb49f0584544f645945206f12b6d4 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -109,6 +109,17 @@ static bool logical_packages_frozen __read_mostly;
 /* Maximum number of SMT threads on any online core */
 int __max_smt_threads __read_mostly;
 
+/* Flag to indicate if a complete sched domain rebuild is required */
+bool x86_topology_update;
+
+int arch_update_cpu_topology(void)
+{
+       int retval = x86_topology_update;
+
+       x86_topology_update = false;
+       return retval;
+}
+
 static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
 {
        unsigned long flags;