• HATAYAMA Daisuke's avatar
    x86/cpu: Always print SMP information in /proc/cpuinfo · a477c859
    HATAYAMA Daisuke authored
    Currently show_cpuinfo_core() displays cpu core information only if
    the number of threads per a whole cores is 2 or larger.
    
    However, this condition doesn't care about the number of
    sockets. For example, this condition doesn't hold on systems
    with two logical cpus consisting of two sockets and a single
    core on each socket - yet the topology information would be
    interesting to see in that case as well.
    
    I don't know whether or not there are processors in real world
    by which such configurations are possible, but at least on
    vitual machine environments, such configuration can occur,
    typically when no explicit SMP information is provided in
    advance.
    
    For example, on qemu/KVM, SMP information is specified via -smp
    command-line option, more specifically, its syntax is:
    
      -smp n[,cores=cores][,threads=threads][,sockets=sockets][,maxcpus=maxcpus]
    
    If this is not specified, qemu tells configuration with
    n-sockets, 1-core and 1-thread to the guest machine, on which
    guest, MP information is not displayed in /proc/cpuinfo.
    
    I saw this situation on VMWare guest environment, too.
    
    To fix this issue, this patch simply removes the condition
    because this information is useful even if there's only 1
    thread.
    Signed-off-by: default avatarHATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
    Cc: Vivek Goyal <vgoyal@redhat.com>
    Cc: H. Peter Anvin <hpa@linux.intel.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
    Link: http://lkml.kernel.org/r/5277D644.4090707@jp.fujitsu.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    a477c859
proc.c 3.84 KB