On Mon, Nov 11 2013 at 7:46pm -0500, Alasdair G Kergon <agk@xxxxxxxxxx> wrote: > On Mon, Nov 11, 2013 at 12:20:48PM -0500, Mike Snitzer wrote: > > From: Joe Thornber <ejt@xxxxxxxxxx> > > > Cache block invalidation is removing an entry from the cache without > > writing it back. Cache blocks can be invalidated via the > > 'invalidate_cblocks' message, which takes an arbitrary number of cblock > > ranges: > > invalidate_cblocks [<cblock>|<cblock begin>-<cblock end>]* > > If we're expecting to need to invalidate a large number of ranges, should we > switch this over to hexadecimal like we did for dm-switch? > > Should we consider changing this to <cblock>+<length> as the dm > interfaces tend to work with a start offset and a length? > > Or will it be that the userspace interface will not be the bottleneck in > this code so it really doesn't matter about attempting to optimise that > part? TBD. Plan is to introduce "invalidate_cblocks_hex" variant if needed. > > +++ b/Documentation/device-mapper/cache.txt > > > The test suite can be found here: > > -https://github.com/jthornber/thinp-test-suite > > +https://github.com/jthornber/device-mapper-test-suite > > It's really not good if URLs in existing documentation become invalid > like this: Could an obvious pointer be placed at the old location to > direct people to the new location? > > Can we document whether or not all the ranges will have been invalidated > before the message returns? > > > + if (!passthrough_mode(&cache->features)) { > > + DMERR("cache has to be in passthrough mode for invalidation"); > > Can we document this too? > > > @@ -2841,6 +3054,12 @@ static int cache_message(struct dm_target *ti, unsigned argc, char **argv) > > + if (!strcmp(argv[0], "invalidate_cblocks")) > > strcasecmp please! Pushed the following commit to address your comments in this patchset, can rebase this commit if you have any further suggestions: http://git.kernel.org/cgit/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=for-next&id=e67df7acf867b654c6eca7d08ee0452e9c5e4534 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
