On Wed, 31 Mar 2021 16:45:05 +0200, Cédric Le Goater wrote:
> ipistorm [*] can be used to benchmark the raw interrupt rate of an
> interrupt controller by measuring the number of IPIs a system can
> sustain. When applied to the XIVE interrupt controller of POWER9 and
> POWER10 systems, a significant drop of the interrupt rate can be
> observed when crossing the second node boundary.
>
> This is due to the fact that a single IPI interrupt is used for all
> CPUs of the system. The structure is shared and the cache line updates
> impact greatly the traffic between nodes and the overall IPI
> performance.
>
> [...]
Patches 2-9 applied to powerpc/next.
[2/9] powerpc/xive: Introduce an IPI interrupt domain
https://git.kernel.org/powerpc/c/7d348494136c8b47c39d1f7ccba28c47d5094a54
[3/9] powerpc/xive: Remove useless check on XIVE_IPI_HW_IRQ
https://git.kernel.org/powerpc/c/1835e72942b5aa779c8ada62aaeba03ab66d92c9
[4/9] powerpc/xive: Simplify xive_core_debug_show()
https://git.kernel.org/powerpc/c/5159d9872823230669b7949ba3caf18c4c314846
[5/9] powerpc/xive: Drop check on irq_data in xive_core_debug_show()
https://git.kernel.org/powerpc/c/a74ce5926b20cd0e6d624a9b2527073a96dfed7f
[6/9] powerpc/xive: Simplify the dump of XIVE interrupts under xmon
https://git.kernel.org/powerpc/c/6bf66eb8f404050030805c65cf39a810892f5f8e
[7/9] powerpc/xive: Fix xmon command "dxi"
https://git.kernel.org/powerpc/c/33e4bc5946432a4ac173fd08e8e30a13ab94d06d
[8/9] powerpc/xive: Map one IPI interrupt per node
https://git.kernel.org/powerpc/c/7dcc37b3eff97379b194adb17eb9a8270512dd1d
[9/9] powerpc/xive: Modernize XIVE-IPI domain with an 'alloc' handler
https://git.kernel.org/powerpc/c/fd6db2892ebaa1383a93b4a609c65b96e615510a
cheers
