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The test creates shmem huge pages shared by both a pare= nt >> and a child processes, where the parent process punches holes in the s= hmem >> to cause folio_split() in the kernel and the child process reads the s= hmem >> in 16 threads to cause filemap_get_entry() in the kernel. >> filemap_get_entry() reads the folio and xarray split by folio_split() >> locklessly. The original test[2] is written in rust and uses memfd (sh= mem >> backed). This C port uses shmem directly. > > Cool. > >> Note: the initial rust to C conversion is done by Cursor. > > Hence the CaMeLcAsE "struct SharedCtl". Fair enough. Will change it to struct shared_ctl. I also got some AI feedback[1] on this test program and will fix them in a new version. I will send the new one late next week, so that I can get feedback from human. :) I will post the AI feedback inline in a separate email. [1] https://sashiko.dev/#/patchset/20260313114037.3593642-1-ziy%40nvidia.= com > >> Link: https://lore.kernel.org/all/CAKNNEtw5_kZomhkugedKMPOG-sxs5Q5OLum= WJdiWXv+C9Yct0w@mail.gmail.com/ [1] >> Link: https://github.com/dfinity/thp-madv-remove-test [2] > > I couldn't immediately find any licensing info there. Bas and Adam, > please advise? And sending your Signed-off-by's would be appropriate. > > Thanks. -- Best Regards, Yan, Zi