• Len Brown's avatar
    x86 idle: remove 32-bit-only "no-hlt" parameter, hlt_works_ok flag · 27be4570
    Len Brown authored
    Remove 32-bit x86 a cmdline param "no-hlt",
    and the cpuinfo_x86.hlt_works_ok that it sets.
    
    If a user wants to avoid HLT, then "idle=poll"
    is much more useful, as it avoids invocation of HLT
    in idle, while "no-hlt" failed to do so.
    
    Indeed, hlt_works_ok was consulted in only 3 places.
    
    First, in /proc/cpuinfo where "hlt_bug yes"
    would be printed if and only if the user booted
    the system with "no-hlt" -- as there was no other code
    to set that flag.
    
    Second, check_hlt() would not invoke halt() if "no-hlt"
    were on the cmdline.
    
    Third, it was consulted in stop_this_cpu(), which is invoked
    by native_machine_halt()/reboot_interrupt()/smp_stop_nmi_callback() --
    all cases where the machine is being shutdown/reset.
    The flag was not consulted in the more frequently invoked
    play_dead()/hlt_play_dead() used in processor offline and suspend.
    
    Since Linux-3.0 there has been a run-time notice upon "no-hlt" invocations
    indicating that it would be removed in 2012.
    Signed-off-by: default avatarLen Brown <len.brown@intel.com>
    Cc: x86@kernel.org
    27be4570
bugs.c 2.43 KB