Will Deacon <will@xxxxxxxxxx> writes: > On Thu, Jun 03, 2021 at 11:15:18AM -0400, Gabriel Krisman Bertazi wrote: >> This introduces three tests: >> >> 1) Sanity check soft dirty basic semantics: allocate area, clean, dirty, >> check if the SD bit flipped. >> >> 2) Check VMA reuse: validate the VM_SOFTDIRTY usage >> >> 3) Check soft-dirty on huge pages >> >> This was motivated by Will Deacon's fix commit 912efa17e512 ("mm: proc: >> Invalidate TLB after clearing soft-dirty page state"). I was tracking the >> same issue that he fixed, and this test would have caught it. >> >> Cc: Will Deacon <will@xxxxxxxxxx> >> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> >> >> -- >> Changes since V1: >> - Fix last minute build break with page_size >> --- >> tools/testing/selftests/Makefile | 1 + >> tools/testing/selftests/soft-dirty/.gitignore | 1 + >> tools/testing/selftests/soft-dirty/Makefile | 9 + >> .../testing/selftests/soft-dirty/soft-dirty.c | 254 ++++++++++++++++++ >> 4 files changed, 265 insertions(+) >> create mode 100644 tools/testing/selftests/soft-dirty/.gitignore >> create mode 100644 tools/testing/selftests/soft-dirty/Makefile >> create mode 100644 tools/testing/selftests/soft-dirty/soft-dirty.c > > Although I think adding a test for this is great (and I certainly wouldn't > want to get in the way of that; quite the opposite), I notice that we > already have test_softdirty() in selftests/vm/madv_populate.c. Would we be > better off extending that test instead of introducing another one? Hi, Will. Thanks for the review. Looks like selftests/vm/madv_populate.c was merged after I sent this, which explains why I missed it. From a quick look, it also doesn't verify the corner case of I'm checking here. I will look into merging the two tests, or at least moving this to vm/ and remove the overlap. Thanks, -- Gabriel Krisman Bertazi