Re: [PATCH 1/1] SGI X86 UV: Provide a System Activity Indicator driver

[Ingo Molnar <mingo@elte.hu>]

* Mike Travis <travis@sgi.com> wrote:

> Subject: SGI X86 UV: Provide a System Activity Indicator driver
> 
> The SGI UV system has no LEDS but uses one of the system controller
> regs to indicate the online internal state of the cpu.  There is a
> heartbeat bit indicating that the cpu is responding to interrupts,
> and an idle bit indicating whether the cpu is idle when the heartbeat
> interrupt occurs.  The current period is one second.
> 
> When a cpu panics, an error code is written by BIOS to this same reg.
> 
> This patchset provides the following:
> 
>   * x86_64: Add base functionality for writing to the specific SCIR's
>     for each cpu.
> 
>   * heartbeat: Invert "heartbeat" bit to indicate the cpu is
>     "interruptible".  If the current thread is the idle thread,
>     then indicate system is "idle".
> 
>   * if hotplug enabled, all bits are set (0xff) when the cpu is disabled.
> 
> Based on linux-2.6.tip/master.
> 
> Signed-off-by: Mike Travis <travis@sgi.com>
> ---
>  arch/x86/include/asm/uv/uv_hub.h |   63 +++++++++++++++++++++++-
>  arch/x86/kernel/genx2apic_uv_x.c |  102 +++++++++++++++++++++++++++++++++++++++
>  2 files changed, 164 insertions(+), 1 deletion(-)

applied to tip/x86/uv, thanks Mike!

Please send the cpu_idle() cleanup patch separately.

Another minor thing i noticed:

@@ -130,7 +140,9 @@ struct uv_hub_info_s {
 	unsigned char	blade_processor_id;
 	unsigned char	m_val;
 	unsigned char	n_val;
+	struct uv_scir_s scir;

please align the new field vertically, like they were aligned before - 
by adding another tab to the whole lineup. (This will also make it 
appear nicer when viewed together with followup definitions below this 
section)

	Ingo