From 2e046b9487dcc60707cac77fb8f744ec830209cd Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Fri, 19 Jun 2009 14:40:51 +0900 Subject: [PATCH] sh: Provide cpu_idle_wait() to fix up cpuidle/SMP build. Crib the x86 cpu_idle_wait() implementation and shove it in with the idle code, subsequently enabling ARCH_HAS_CPU_IDLE_WAIT. Signed-off-by: Paul Mundt --- arch/sh/Kconfig | 3 +++ arch/sh/include/asm/system.h | 1 + arch/sh/kernel/idle.c | 23 ++++++++++++++++++++++- 3 files changed, 26 insertions(+), 1 deletion(-) diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index ac1c620d1c7d..09c0aef31d03 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -151,6 +151,9 @@ config ARCH_NO_VIRT_TO_BUS config ARCH_HAS_DEFAULT_IDLE def_bool y +config ARCH_HAS_CPU_IDLE_WAIT + def_bool y + config IO_TRAPPED bool diff --git a/arch/sh/include/asm/system.h b/arch/sh/include/asm/system.h index a88895e6dcb0..ab79e1f4fbe0 100644 --- a/arch/sh/include/asm/system.h +++ b/arch/sh/include/asm/system.h @@ -154,6 +154,7 @@ extern struct dentry *sh_debugfs_root; void per_cpu_trap_init(void); void default_idle(void); +void cpu_idle_wait(void); asmlinkage void break_point_trap(void); diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index f35ed0348850..27ff2dc093c7 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -1,7 +1,7 @@ /* * The idle loop for all SuperH platforms. * - * Copyright (C) 2002 - 2008 Paul Mundt + * Copyright (C) 2002 - 2009 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -79,3 +80,23 @@ void cpu_idle(void) check_pgt_cache(); } } + +static void do_nothing(void *unused) +{ +} + +/* + * cpu_idle_wait - Used to ensure that all the CPUs discard old value of + * pm_idle and update to new pm_idle value. Required while changing pm_idle + * handler on SMP systems. + * + * Caller must have changed pm_idle to the new value before the call. Old + * pm_idle value will not be used by any CPU after the return of this function. + */ +void cpu_idle_wait(void) +{ + smp_mb(); + /* kick all the CPUs so that they exit out of pm_idle */ + smp_call_function(do_nothing, NULL, 1); +} +EXPORT_SYMBOL_GPL(cpu_idle_wait); -- 2.20.1