[PATCH] x86/irq: Fix comment on IRQ vector layout

[PATCH] x86/irq: Fix comment on IRQ vector layout

[Sohil Mehta]

commit f5a3562ec9dd ("x86/irq: Reserve a per CPU IDT vector for posted
MSIs") changed the first system vector from LOCAL_TIMER_VECTOR to
POSTED_MSI_NOTIFICATION_VECTOR. Reflect this change in the vector layout
comment as well.

However, instead of pointing to the specific vector, use the
FIRST_SYSTEM_VECTOR indirection which essentially refers to the same.
This would avoid unnecessary modifications to the same comment whenever
additional system vectors get added.

Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
---
 arch/x86/include/asm/irq_vectors.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 13aea8fc3d45..970a89e7c6b7 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -18,8 +18,8 @@
  *  Vectors   0 ...  31 : system traps and exceptions - hardcoded events
  *  Vectors  32 ... 127 : device interrupts
  *  Vector  128         : legacy int80 syscall interface
- *  Vectors 129 ... LOCAL_TIMER_VECTOR-1
- *  Vectors LOCAL_TIMER_VECTOR ... 255 : special interrupts
+ *  Vectors 129 ... FIRST_SYSTEM_VECTOR-1
+ *  Vectors FIRST_SYSTEM_VECTOR ... 255 : special interrupts
  *
  * 64-bit x86 has per CPU IDT tables, 32-bit has one shared IDT table.
  *
-- 
2.34.1

Re: [PATCH] x86/irq: Fix comment on IRQ vector layout

[Jacob Pan]

On Tue, 18 Jun 2024 20:13:20 +0000, Sohil Mehta <sohil.mehta@intel.com>
wrote:

> commit f5a3562ec9dd ("x86/irq: Reserve a per CPU IDT vector for posted
> MSIs") changed the first system vector from LOCAL_TIMER_VECTOR to
> POSTED_MSI_NOTIFICATION_VECTOR. Reflect this change in the vector layout
> comment as well.
> 
> However, instead of pointing to the specific vector, use the
> FIRST_SYSTEM_VECTOR indirection which essentially refers to the same.
> This would avoid unnecessary modifications to the same comment whenever
> additional system vectors get added.
> 
> Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
> ---
>  arch/x86/include/asm/irq_vectors.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/include/asm/irq_vectors.h
> b/arch/x86/include/asm/irq_vectors.h index 13aea8fc3d45..970a89e7c6b7
> 100644 --- a/arch/x86/include/asm/irq_vectors.h
> +++ b/arch/x86/include/asm/irq_vectors.h
> @@ -18,8 +18,8 @@
>   *  Vectors   0 ...  31 : system traps and exceptions - hardcoded events
>   *  Vectors  32 ... 127 : device interrupts
>   *  Vector  128         : legacy int80 syscall interface
> - *  Vectors 129 ... LOCAL_TIMER_VECTOR-1
> - *  Vectors LOCAL_TIMER_VECTOR ... 255 : special interrupts
> + *  Vectors 129 ... FIRST_SYSTEM_VECTOR-1
Should this range be explicitly labeled as "device interrupts"?

Thanks,

Jacob

Re: [PATCH] x86/irq: Fix comment on IRQ vector layout

[Sohil Mehta]

>>   *  Vectors   0 ...  31 : system traps and exceptions - hardcoded events
>>   *  Vectors  32 ... 127 : device interrupts
>>   *  Vector  128         : legacy int80 syscall interface
>> - *  Vectors 129 ... LOCAL_TIMER_VECTOR-1
>> - *  Vectors LOCAL_TIMER_VECTOR ... 255 : special interrupts
>> + *  Vectors 129 ... FIRST_SYSTEM_VECTOR-1
> Should this range be explicitly labeled as "device interrupts"?
> 

I thought about that as well. I wasn't sure why it was left out in the
first place.

Will change it in the next version unless someone suggests otherwise.

-Sohil