lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

ACPI, intel_idle: Cleanup idle= internal variables

Browse Source 
Having four variables for the same thing:
  idle_halt, idle_nomwait, force_mwait and boot_option_idle_overrides
is rather confusing and unnecessary complex.

if idle= boot param is passed, only set up one variable:
boot_option_idle_overrides

Introduces following functional changes/fixes:
  - intel_idle driver does not register if any idle=xy
    boot param is passed.
  - processor_idle.c will also not register a cpuidle driver
    and get active if idle=halt is passed.
    Before a cpuidle driver with one (C1, halt) state got registered
    Now the default_idle function will be used which finally uses
    the same idle call to enter sleep state (safe_halt()), but
    without registering a whole cpuidle driver.

That means idle= param will always avoid cpuidle drivers to register
with one exception (same behavior as before):
idle=nomwait
may still register acpi_idle cpuidle driver, but C1 will not use
mwait, but hlt. This can be a workaround for IO based deeper sleep
states where C1 mwait causes problems.

Signed-off-by: Thomas Renninger <trenn@suse.de>
cc: x86@kernel.org
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Thomas Renninger
2010-11-03 17:06:14 +01:00
committed by Len Brown
parent d8c216cfa5
commit d18960494f
7 changed files with 32 additions and 40 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/idle/intel_idle.c
View File

@@ -404,6 +404,10 @@ static int __init intel_idle_init(void)
{
int retval;
/* Do not load intel_idle at all for now if idle= is passed */
if (boot_option_idle_override != IDLE_NO_OVERRIDE)
return -ENODEV;
retval = intel_idle_probe();
if (retval)
return retval;