From: Amir Goldstein Subject: Re: [fstests PATCH v2] generic: add test for DAX MAP_SYNC support Date: Wed, 25 Oct 2017 15:19:22 +0300 Message-ID: References: <20171020052943.15104-1-ross.zwisler@linux.intel.com> <20171020212556.30816-1-ross.zwisler@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-xfs , Jan Kara , Eryu Guan , Mike Snitzer , linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, Josef Bacik , Dave Chinner , linux-kernel , fstests , linux-raid-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Christoph Hellwig , linux-fsdevel , Ext4 , Shaohua Li , Alasdair Kergon To: Ross Zwisler Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-ext4.vger.kernel.org On Sun, Oct 22, 2017 at 9:56 AM, Amir Goldstein wrote: > On Sat, Oct 21, 2017 at 12:25 AM, Ross Zwisler > wrote: >> Add a test that exercises DAX's new MAP_SYNC flag. >> >> This test creates a file and writes to it via an mmap(), but never syncs >> via fsync/msync. This process is tracked via dm-log-writes, then replayed. >> >> If MAP_SYNC is working the dm-log-writes replay will show the test file >> with 1MiB of on-media block allocations. This is because each allocating >> page fault included an implicit metadata sync. If MAP_SYNC isn't working >> (which you can test by fiddling with the parameters to mmap()) the file >> will be smaller or missing entirely. >> >> Note that dm-log-writes doesn't track the data that we write via the >> mmap(), so we can't do any data integrity checking. We can only verify >> that the metadata writes for the page faults happened. >> >> Signed-off-by: Ross Zwisler >> >> --- >> >> Changes since v1: >> - Addressed review feedback from Amir. Thank you for the review! > > Looks good. > >> >> --- >> .gitignore | 1 + >> common/dmlogwrites | 1 - >> src/Makefile | 3 +- >> src/t_map_sync.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++ >> tests/generic/466 | 76 ++++++++++++++++++++++++++++++++++++++++++ >> tests/generic/466.out | 3 ++ >> tests/generic/group | 1 + >> 7 files changed, 175 insertions(+), 2 deletions(-) >> create mode 100644 src/t_map_sync.c >> create mode 100755 tests/generic/466 >> create mode 100644 tests/generic/466.out >> >> diff --git a/.gitignore b/.gitignore >> index 2014c08..9fc0695 100644 >> --- a/.gitignore >> +++ b/.gitignore >> @@ -119,6 +119,7 @@ >> /src/t_getcwd >> /src/t_holes >> /src/t_immutable >> +/src/t_map_sync >> /src/t_mmap_cow_race >> /src/t_mmap_dio >> /src/t_mmap_fallocate >> diff --git a/common/dmlogwrites b/common/dmlogwrites >> index 247c744..5b57df9 100644 >> --- a/common/dmlogwrites >> +++ b/common/dmlogwrites >> @@ -23,7 +23,6 @@ _require_log_writes() >> [ -z "$LOGWRITES_DEV" -o ! -b "$LOGWRITES_DEV" ] && \ >> _notrun "This test requires a valid \$LOGWRITES_DEV" >> >> - _exclude_scratch_mount_option dax Wait. It this really ok to relax no dax from _require_log_writes()? Shouldn't you check log-write target version or something to verify that log-writes+dax is really supported? I think you should. >> _require_dm_target log-writes >> _require_test_program "log-writes/replay-log" >> }