Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in /proc/self/smaps)
From: Christoph Hellwig <hch@infradead.org>
Date: 2016-09-12 05:27:03
Also in:
kvm, linux-fsdevel, lkml, nvdimm
On Thu, Sep 08, 2016 at 04:56:36PM -0600, Ross Zwisler wrote:
I think this goes back to our previous discussion about support for the PMEM programming model. Really I think what NVML needs isn't a way to tell if it is getting a DAX mapping, but whether it is getting a DAX mapping on a filesystem that fully supports the PMEM programming model. This of course is defined to be a filesystem where it can do all of its flushes from userspace safely and never call fsync/msync, and that allocations that happen in page faults will be synchronized to media before the page fault completes.
That's a an easy way to flag: you will never get that from a Linux filesystem, period. NVML folks really need to stop taking crack and dreaming this could happen. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>