RE: [PATCH][2.6] fix i386 idle routine selection

[Pallipadi, Venkatesh]

The original idea of setting it back to default_idle(),
was to handle the cases:
1) CPU 0 says it can do mwait and CPU 1 later says it 
cannot do mwait
2) CPU 0 says it cannot do mwait and later CPU 1 says
that it can do mwait

Not that I know of any system like that. But, ideally 
mwait_idle should be set only when all CPUs say that 
they can do it.

So how about this patch.

Thanks,
Venki


>-----Original Message-----
>From: robomod@xxxxxxxxxxx [mailto:robomod@xxxxxxxxxxx] On 
>Behalf Of Zwane Mwaikambo
>Sent: Sunday, August 08, 2004 11:20 AM
>Subject: [PATCH][2.6] fix i386 idle routine selection
>
>This was broken when the mwait stuff went in since it executes 
>after the
>initial idle_setup() has already selected an idle routine and 
>overrides it
>with default_idle.
>
>Signed-off-by: Zwane Mwaikambo <zwane@xxxxxxxxxxx>
>
>Index: linux-2.6.8-rc3-mm1-amd64/arch/i386/kernel/process.c
>===================================================================
>RCS file: 
>/home/cvsroot/linux-2.6.8-rc3-mm1/arch/i386/kernel/process.c,v
>retrieving revision 1.1.1.1
>diff -u -p -B -r1.1.1.1 process.c
>--- linux-2.6.8-rc3-mm1-amd64/arch/i386/kernel/process.c	
>5 Aug 2004 16:37:39 -0000	1.1.1.1
>+++ linux-2.6.8-rc3-mm1-amd64/arch/i386/kernel/process.c	
>8 Aug 2004 18:14:32 -0000
>@@ -226,10 +226,7 @@ void __init select_idle_routine(const st
> 			printk("using mwait in idle threads.\n");
> 			pm_idle = mwait_idle;
> 		}
>-		return;
> 	}
>-	pm_idle = default_idle;
>-	return;
> }
>
> static int __init idle_setup (char *str)
>Index: linux-2.6.8-rc3-mm1-amd64/arch/x86_64/kernel/process.c
>===================================================================
>RCS file: 
>/home/cvsroot/linux-2.6.8-rc3-mm1/arch/x86_64/kernel/process.c,v
>retrieving revision 1.1.1.1
>diff -u -p -B -r1.1.1.1 process.c
>--- linux-2.6.8-rc3-mm1-amd64/arch/x86_64/kernel/process.c	
>5 Aug 2004 16:37:48 -0000	1.1.1.1
>+++ linux-2.6.8-rc3-mm1-amd64/arch/x86_64/kernel/process.c	
>8 Aug 2004 18:12:22 -0000
>@@ -180,10 +180,7 @@ void __init select_idle_routine(const st
> 			}
> 			pm_idle = mwait_idle;
> 		}
>-		return;
> 	}
>-	pm_idle = default_idle;
>-	return;
> }
>
> static int __init idle_setup (char *str)
>-
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Attachment: mwait_bug.patch
Description: mwait_bug.patch