On Mon, Oct 27, 2014 at 04:31:16PM -0400, David Miller wrote: > From: Darren Hart <dvh...@linux.intel.com> > Date: Mon, 27 Oct 2014 13:29:14 -0700 > > > On 10/27/14 12:56, David Miller wrote: > >> I'd like to suggest that you add a test that triggers transparent > >> hugepages, because if an architecture doesn't implement > >> __get_user_pages_fast() such futexes cause a machine to hang. > >> > >> I hacked up something simple that took the existing performance > >> test and made it operate in a register allocated using memalign(). > >> > >> I would suggest doing a memalign(HUGEPAGE_SIZE, HUGEPAGE_SIZE) then > >> iterating running a futex test within each normal page within that > >> hugepage. > > > > Do you want this option for the performance tests, or would a less > > intensive functional test be sufficient? > > I think a functional test is sufficient.
Hi David, >From your suggestion I put together a simple transparent hugepage functional test. See the "thp" branch, functional/futex_wait_thp.c. I'd like your thoughts on if this functions as desired. Is the simple single threaded timeout sufficient, or would you prefer to see a waiter/waker pair of threads for each iteration? Some TODOs still: I wasn't sure if there was a way to test for hugepagesize and my quick search didn't reveal anything (other than /proc/meminfo). Check at runtime if the test is getting a huge page, otherwise it just reports success, but used several regular pages instead. -- Darren Hart Intel Open Source Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
