Fix-Point opened a new pull request, #14689:
URL: https://github.com/apache/nuttx/pull/14689

   ## Summary
   
   This patch is necessary to optimize the handling of SGI (Software Generated 
Interrupts) in a virtualized environment on ARM64 architecture. The original 
implementation required reading the IGROUPR0 register each time an SGI was 
sent, which, due to the GIC Redistributor being a purely emulated device, 
caused a VM exit. This VM exit leads to significant performance degradation. 
The patch addresses this issue by replacing the read operation with a 
predefined value set during the initialization in `gicv3_cpuif_init`, assuming 
that this value remains unmodified post-initialization.
   
   ## Impact
   
   The change primarily affects the performance of virtualized environments by 
reducing the number of VM exits caused by SGI handling. Users running virtual 
machines on ARM64 hardware should experience improved performance, especially 
in scenarios with frequent SGI usage. There are no direct changes to the build 
process, hardware requirements, or documentation. Security and compatibility 
are not directly impacted by this change, but the overall system performance 
may be enhanced due to reduced VM exits.
   
   ## Testing
   
   The change was verified on QEMU-virt/arm64.
   


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