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cpu/SMT: Remove topology_smt_supported()
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Since the maximum number of threads is now passed to cpu_smt_set_num_threads(),
checking that value is enough to know whether SMT is supported.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
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/20230705145143.40545-6-ldufour@linux.ibm.com
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Laurent Dufour authored and Thomas Gleixner committed Jul 28, 2023
1 parent 447ae4a commit 91b4a7d
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Showing 3 changed files with 2 additions and 12 deletions.
2 changes: 0 additions & 2 deletions arch/x86/include/asm/topology.h
Original file line number Diff line number Diff line change
Expand Up @@ -141,7 +141,6 @@ static inline int topology_max_smt_threads(void)
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);
bool topology_smt_supported(void);

extern struct cpumask __cpu_primary_thread_mask;
#define cpu_primary_thread_mask ((const struct cpumask *)&__cpu_primary_thread_mask)
Expand All @@ -164,7 +163,6 @@ static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; }
static inline int topology_max_die_per_package(void) { return 1; }
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 /* !CONFIG_SMP */

static inline void arch_fix_phys_package_id(int num, u32 slot)
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8 changes: 0 additions & 8 deletions arch/x86/kernel/smpboot.c
Original file line number Diff line number Diff line change
Expand Up @@ -326,14 +326,6 @@ static void notrace start_secondary(void *unused)
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
}

/**
* 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
* @phys_pkg: The physical package id to map
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4 changes: 2 additions & 2 deletions kernel/cpu.c
Original file line number Diff line number Diff line change
Expand Up @@ -621,7 +621,7 @@ void __init cpu_smt_set_num_threads(unsigned int num_threads,
{
WARN_ON(!num_threads || (num_threads > max_threads));

if (!topology_smt_supported())
if (max_threads == 1)
cpu_smt_control = CPU_SMT_NOT_SUPPORTED;

cpu_smt_max_threads = max_threads;
Expand Down Expand Up @@ -1801,7 +1801,7 @@ early_param("cpuhp.parallel", parallel_bringup_parse_param);

static inline bool cpuhp_smt_aware(void)
{
return topology_smt_supported();
return cpu_smt_max_threads > 1;
}

static inline const struct cpumask *cpuhp_get_primary_thread_mask(void)
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