summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorThomas Gleixner <tglx@linutronix.de>2018-06-21 10:37:20 +0200
committerThomas Gleixner <tglx@linutronix.de>2018-06-21 14:20:57 +0200
commitf048c399e0f7490ab7296bc2c255d37eb14a9675 (patch)
tree6c4cac4f34e78864aaba1088c76ac052203f7976
parent6a4d2657e048f096c7ffcad254010bd94891c8c0 (diff)
downloadop-kernel-dev-f048c399e0f7490ab7296bc2c255d37eb14a9675.zip
op-kernel-dev-f048c399e0f7490ab7296bc2c255d37eb14a9675.tar.gz
x86/topology: Provide topology_smt_supported()
Provide information whether SMT is supoorted by the CPUs. Preparatory patch for SMT control mechanism. Suggested-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r--arch/x86/include/asm/topology.h2
-rw-r--r--arch/x86/kernel/smpboot.c8
2 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 661e361..453cf38 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -125,6 +125,7 @@ static inline int topology_max_smt_threads(void)
int topology_update_package_map(unsigned int apicid, unsigned int cpu);
int topology_phys_to_logical_pkg(unsigned int pkg);
bool topology_is_primary_thread(unsigned int cpu);
+bool topology_smt_supported(void);
#else
#define topology_max_packages() (1)
static inline int
@@ -132,6 +133,7 @@ topology_update_package_map(unsigned int apicid, unsigned int cpu) { return 0; }
static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; }
static inline int topology_max_smt_threads(void) { return 1; }
static inline bool topology_is_primary_thread(unsigned int cpu) { return true; }
+static inline bool topology_smt_supported(void) { return false; }
#endif
static inline void arch_fix_phys_package_id(int num, u32 slot)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index f9c7312..7f7def9 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -275,6 +275,14 @@ bool topology_is_primary_thread(unsigned int cpu)
}
/**
+ * topology_smt_supported - Check whether SMT is supported by the CPUs
+ */
+bool topology_smt_supported(void)
+{
+ return smp_num_siblings > 1;
+}
+
+/**
* topology_phys_to_logical_pkg - Map a physical package id to a logical
*
* Returns logical package id or -1 if not found
OpenPOWER on IntegriCloud