• Andi Kleen's avatar
    x86/topology: Add topology_max_smt_threads() · 70b8301f
    Andi Kleen authored
    For SMT specific workarounds it is useful to know if SMT is active
    on any online CPU in the system. This currently requires a loop
    over all online CPUs.
    
    Add a global variable that is updated with the maximum number
    of smt threads on any CPU on online/offline, and use it for
    topology_max_smt_threads()
    
    The single call is easier to use than a loop.
    
    Not exported to user space because user space already can use
    the existing sibling interfaces to find this out.
    Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
    Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
    Cc: Jiri Olsa <jolsa@redhat.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Stephane Eranian <eranian@google.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Vince Weaver <vincent.weaver@maine.edu>
    Cc: acme@kernel.org
    Cc: jolsa@kernel.org
    Link: http://lkml.kernel.org/r/1463703002-19686-2-git-send-email-andi@firstfloor.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    70b8301f
smpboot.c 41.3 KB