From d18960494f65ca4fa0d67c865aaca99452070d15 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Wed, 3 Nov 2010 17:06:14 +0100 Subject: ACPI, intel_idle: Cleanup idle= internal variables 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 cc: x86@kernel.org Signed-off-by: Len Brown --- arch/x86/kernel/process.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) (limited to 'arch/x86/kernel/process.c') diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 57d1868a86aa..b6472153e45b 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -22,11 +22,6 @@ #include #include -unsigned long idle_halt; -EXPORT_SYMBOL(idle_halt); -unsigned long idle_nomwait; -EXPORT_SYMBOL(idle_nomwait); - struct kmem_cache *task_xstate_cachep; EXPORT_SYMBOL_GPL(task_xstate_cachep); @@ -328,7 +323,7 @@ long sys_execve(const char __user *name, /* * Idle related variables and functions */ -unsigned long boot_option_idle_override = 0; +unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; EXPORT_SYMBOL(boot_option_idle_override); /* @@ -499,7 +494,6 @@ static void poll_idle(void) * * idle=mwait overrides this decision and forces the usage of mwait. */ -static int __cpuinitdata force_mwait; #define MWAIT_INFO 0x05 #define MWAIT_ECX_EXTENDED_INFO 0x01 @@ -509,7 +503,7 @@ static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c) { u32 eax, ebx, ecx, edx; - if (force_mwait) + if (boot_option_idle_override == IDLE_FORCE_MWAIT) return 1; if (c->cpuid_level < MWAIT_INFO) @@ -629,9 +623,10 @@ static int __init idle_setup(char *str) if (!strcmp(str, "poll")) { printk("using polling idle threads.\n"); pm_idle = poll_idle; - } else if (!strcmp(str, "mwait")) - force_mwait = 1; - else if (!strcmp(str, "halt")) { + boot_option_idle_override = IDLE_POLL; + } else if (!strcmp(str, "mwait")) { + boot_option_idle_override = IDLE_FORCE_MWAIT; + } else if (!strcmp(str, "halt")) { /* * When the boot option of idle=halt is added, halt is * forced to be used for CPU idle. In such case CPU C2/C3 @@ -640,8 +635,7 @@ static int __init idle_setup(char *str) * the boot_option_idle_override. */ pm_idle = default_idle; - idle_halt = 1; - return 0; + boot_option_idle_override = IDLE_HALT; } else if (!strcmp(str, "nomwait")) { /* * If the boot option of "idle=nomwait" is added, @@ -649,12 +643,10 @@ static int __init idle_setup(char *str) * states. In such case it won't touch the variable * of boot_option_idle_override. */ - idle_nomwait = 1; - return 0; + boot_option_idle_override = IDLE_NOMWAIT; } else return -1; - boot_option_idle_override = 1; return 0; } early_param("idle", idle_setup); -- cgit v1.2.3