On Wed, Aug 07, 2019 at 08:30:02AM +0200, Christoph Hellwig wrote:
On Tue, Aug 06, 2019 at 12:50:10AM -0700, Hugh Dickins wrote:
Though personally I'm averse to managing "f"objects through "m"interfaces, which can get ridiculous (notably, MADV_HUGEPAGE works on the virtual address of a mapping, but the huge-or-not alignment of that mapping must have been decided previously). In Google we do use fcntls F_HUGEPAGE and F_NOHUGEPAGE to override on a per-file basis - one day I'll get to upstreaming those.
Such an interface seems very useful, although the two fcntls seem a bit odd.
But I think the point here is that the i915 has its own somewhat odd instance of tmpfs. If we could pass the equivalent of the huge=* options to shmem_file_setup all that garbage (including the shmem_file_setup_with_mnt function) could go away.
... or follow shmem_file_super() with whatever that fcntl maps to internally. I would really love to get rid of that i915 kludge.