Re: [linux-pm] [PATCH] CPUidle: compile fix for non-x86

Venki Pallipadi
2008-02-09T01:07:20Z

On Thu, Jan 31, 2008 at 10:40:46PM -0500, Len Brown wrote:
> Applied w/ Rafael's comment fixes included.
>
> thanks,
> -Len

Len pointed out that the last posted version of this patch gave compile error
on IA64. So, here goes yet another rewrite of the patch.

[PATCH] CPU_IDLE: Compile fix for non x86 arch
From: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>

Convert cpu_idle_wait() to cpuidle_kick_cpus() which is
SMP-only, and gives error on non supported CPU.

Changes from last patch sent by Kevin:
Moved the definition of kick_cpus back to cpuidle.c from cpuidle.h:
* Having it in .h gives #error on archs which includes the header file without
actually having CPU_IDLE configured. To make it work in .h, we need one more
#ifdef around that code which makes it messy.
* Also, the function is only called from one file. So, it can be in declared
statically in .c rather than making it available to everyone who includes
the .h file.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Kevin Hilman <khilman@mvista.com>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
Index: linux-2.6.25-rc/arch/x86/Kconfig
===================================================================
--- linux-2.6.25-rc.orig/arch/x86/Kconfig
+++ linux-2.6.25-rc/arch/x86/Kconfig
@@ -105,6 +105,9 @@ config ARCH_HAS_ILOG2_U32
config ARCH_HAS_ILOG2_U64
def_bool n

+config ARCH_HAS_CPU_IDLE_WAIT
+ def_bool y
+
config GENERIC_CALIBRATE_DELAY
def_bool y

Index: linux-2.6.25-rc/drivers/cpuidle/cpuidle.c
===================================================================
--- linux-2.6.25-rc.orig/drivers/cpuidle/cpuidle.c
+++ linux-2.6.25-rc/drivers/cpuidle/cpuidle.c
@@ -27,6 +27,17 @@ static void (*pm_idle_old)(void);

static int enabled_devices;

+#if defined(CONFIG_ARCH_HAS_CPU_IDLE_WAIT)
+static void cpuidle_kick_cpus(void)
+{
+ cpu_idle_wait();
+}
+#elif defined(CONFIG_SMP)
+# error "Arch needs cpu_idle_wait() equivalent here"
+#else /* !CONFIG_ARCH_HAS_CPU_IDLE_WAIT && !CONFIG_SMP */
+static void cpuidle_kick_cpus(void) {}
+#endif
+
/**
* cpuidle_idle_call - the main idle loop
*
@@ -83,7 +94,7 @@ void cpuidle_uninstall_idle_handler(void
{
if (enabled_devices && (pm_idle != pm_idle_old)) {
pm_idle = pm_idle_old;
- cpu_idle_wait();
+ cpuidle_kick_cpus();
}
}