Messages in this thread | | | From | David Laight <> | Subject | RE: [RFC PATCH 2/3] x86/io: implement 256-bit IO read and write | Date | Tue, 20 Mar 2018 14:40:19 +0000 |
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From: Rahul Lakkireddy > Sent: 20 March 2018 13:32 ... > On High Availability Server, the logs of the failing system must be > collected as quickly as possible. So, we're concerned with the amount > of time taken to collect our large on-chip memory. We see improvement > in doing 256-bit reads at a time.
Two other options:
1) Get the device to DMA into host memory.
2) Use mmap() (and vm_iomap_memory() in your driver) to get direct userspace access to the (I assume) PCIe memory space. You can then use whatever copy instructions the cpu has. (Just don't use memcpy().)
David
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