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authorMichael Ellerman <mpe@ellerman.id.au>2023-07-05 16:51:35 +0200
committerThomas Gleixner <tglx@linutronix.de>2023-07-28 09:53:36 +0200
commit3f9169196be55590a794b52f49637561ddd1ba4f (patch)
tree0ebae119bbb8cea5eb762b241aec85c4353b2857
parent7a4dcb4a5de1214c4a59448a759e2e264c2c4473 (diff)
downloadlwn-3f9169196be55590a794b52f49637561ddd1ba4f.tar.gz
lwn-3f9169196be55590a794b52f49637561ddd1ba4f.zip
cpu/SMT: Move SMT prototypes into cpu_smt.h
In order to export the cpuhp_smt_control enum as part of the interface between generic and architecture code, the architecture code needs to include asm/topology.h. But that leads to circular header dependencies. So split the enum and related declarations into a separate header. [ ldufour: Reworded the commit's description ] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Zhang Rui <rui.zhang@intel.com> Link: https://lore.kernel.org/r/20230705145143.40545-3-ldufour@linux.ibm.com
-rw-r--r--arch/x86/include/asm/topology.h2
-rw-r--r--include/linux/cpu.h25
-rw-r--r--include/linux/cpu_smt.h29
-rw-r--r--kernel/cpu.c1
4 files changed, 33 insertions, 24 deletions
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index caf41c4869a0..ae49ed4417d0 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -136,6 +136,8 @@ static inline int topology_max_smt_threads(void)
return __max_smt_threads;
}
+#include <linux/cpu_smt.h>
+
int topology_update_package_map(unsigned int apicid, unsigned int cpu);
int topology_update_die_map(unsigned int dieid, unsigned int cpu);
int topology_phys_to_logical_pkg(unsigned int pkg);
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 6e6e57ec69e8..6b326a9e8191 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -18,6 +18,7 @@
#include <linux/compiler.h>
#include <linux/cpumask.h>
#include <linux/cpuhotplug.h>
+#include <linux/cpu_smt.h>
struct device;
struct device_node;
@@ -204,30 +205,6 @@ void cpuhp_report_idle_dead(void);
static inline void cpuhp_report_idle_dead(void) { }
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-enum cpuhp_smt_control {
- CPU_SMT_ENABLED,
- CPU_SMT_DISABLED,
- CPU_SMT_FORCE_DISABLED,
- CPU_SMT_NOT_SUPPORTED,
- CPU_SMT_NOT_IMPLEMENTED,
-};
-
-#if defined(CONFIG_SMP) && defined(CONFIG_HOTPLUG_SMT)
-extern enum cpuhp_smt_control cpu_smt_control;
-extern void cpu_smt_disable(bool force);
-extern void cpu_smt_check_topology(void);
-extern bool cpu_smt_possible(void);
-extern int cpuhp_smt_enable(void);
-extern int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval);
-#else
-# define cpu_smt_control (CPU_SMT_NOT_IMPLEMENTED)
-static inline void cpu_smt_disable(bool force) { }
-static inline void cpu_smt_check_topology(void) { }
-static inline bool cpu_smt_possible(void) { return false; }
-static inline int cpuhp_smt_enable(void) { return 0; }
-static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; }
-#endif
-
extern bool cpu_mitigations_off(void);
extern bool cpu_mitigations_auto_nosmt(void);
diff --git a/include/linux/cpu_smt.h b/include/linux/cpu_smt.h
new file mode 100644
index 000000000000..722c2e306fef
--- /dev/null
+++ b/include/linux/cpu_smt.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_CPU_SMT_H_
+#define _LINUX_CPU_SMT_H_
+
+enum cpuhp_smt_control {
+ CPU_SMT_ENABLED,
+ CPU_SMT_DISABLED,
+ CPU_SMT_FORCE_DISABLED,
+ CPU_SMT_NOT_SUPPORTED,
+ CPU_SMT_NOT_IMPLEMENTED,
+};
+
+#if defined(CONFIG_SMP) && defined(CONFIG_HOTPLUG_SMT)
+extern enum cpuhp_smt_control cpu_smt_control;
+extern void cpu_smt_disable(bool force);
+extern void cpu_smt_check_topology(void);
+extern bool cpu_smt_possible(void);
+extern int cpuhp_smt_enable(void);
+extern int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval);
+#else
+# define cpu_smt_control (CPU_SMT_NOT_IMPLEMENTED)
+static inline void cpu_smt_disable(bool force) { }
+static inline void cpu_smt_check_topology(void) { }
+static inline bool cpu_smt_possible(void) { return false; }
+static inline int cpuhp_smt_enable(void) { return 0; }
+static inline int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) { return 0; }
+#endif
+
+#endif /* _LINUX_CPU_SMT_H_ */
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 03309f2f35a4..e02204c4675a 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -592,6 +592,7 @@ static void lockdep_release_cpus_lock(void)
void __weak arch_smt_update(void) { }
#ifdef CONFIG_HOTPLUG_SMT
+
enum cpuhp_smt_control cpu_smt_control __read_mostly = CPU_SMT_ENABLED;
void __init cpu_smt_disable(bool force)