On Thu, 6 Jun 2024 20:36:19 +0000 "Pankaj Raghav (Samsung)" <[email protected]> wrote:
> From: Pankaj Raghav <[email protected]> > > create_pagecache_thp_and_fd() in split_huge_page_test.c used the > variable dummy to perform mmap read. > > However, this test was skipped even on XFS which has large folio > support. The issue was compiler (gcc 13.2.0) was optimizing out the > dummy variable, therefore, not creating huge page in the page cache. > > Use asm volatile() trick to force the compiler not to optimize out > the loop where we read from the mmaped addr. This is similar to what is > being done in other tests (cow.c, etc) > > As the variable is now used in the asm statement, remove the unused > attribute. > What are the runtime effects of this change? An inappropriate test failure? If so, shouldn't we fix 6.9.x kernels also? And is fc4d182316bd ("mm: huge_memory: enable debugfs to split huge pages to any order") an appropriate Fixes: target?
