From c52787b590634646d4da3d8f23c4532ba050d40d Mon Sep 17 00:00:00 2001 From: Balbir Singh Date: Fri, 8 Jan 2021 23:10:52 +1100 Subject: x86/smp: Add a per-cpu view of SMT state A new field smt_active in cpuinfo_x86 identifies if the current core/cpu is in SMT mode or not. This is helpful when the system has some of its cores with threads offlined and can be used for cases where action is taken based on the state of SMT. The upcoming support for paranoid L1D flush will make use of this information. Suggested-by: Thomas Gleixner Signed-off-by: Balbir Singh Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20210108121056.21940-2-sblbir@amazon.com --- arch/x86/include/asm/processor.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index f3020c54e2cb..1e0d13c9fda6 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -136,6 +136,8 @@ struct cpuinfo_x86 { u16 logical_die_id; /* Index into per_cpu list: */ u16 cpu_index; + /* Is SMT active on this core? */ + bool smt_active; u32 microcode; /* Address space bits used by the cache internally */ u8 x86_cache_bits; -- cgit v1.2.3