Re: [RFC PATCH] swiotlb: Add Child IO TLB mem support

2022-04-29 Thread Tianyu Lan
On 4/29/2022 10:21 PM, Tianyu Lan wrote: From: Tianyu Lan Traditionally swiotlb was not performance critical because it was only used for slow devices. But in some setups, like TDX/SEV confidential guests, all IO has to go through swiotlb. Currently swiotlb only has a single lock. Under high IO

[RFC PATCH] swiotlb: Add Child IO TLB mem support

2022-04-29 Thread Tianyu Lan
From: Tianyu Lan Traditionally swiotlb was not performance critical because it was only used for slow devices. But in some setups, like TDX/SEV confidential guests, all IO has to go through swiotlb. Currently swiotlb only has a single lock. Under high IO load with multiple CPUs this can lead to s