Am 24.09.2014 um 21:48 hat Max Reitz geschrieben: > The BDS filename field is generally only used when opening disk images > or emitting error or warning messages, the only exception to this rule > is the map command of qemu-img. However, using exact_filename there > instead should not be a problem. Therefore, we can drop the filename > field from the BlockDriverState and use a function instead which builds > the filename from scratch when called. > > This is slower than reading a static char array but the problem of that > static array is that it may become obsolete due to changes in any > BlockDriverState or in the BDS graph. Using a function which rebuilds > the filename every time it is called resolves this problem. > > The disadvantage of worse performance is negligible, on the other hand. > After patch 2 of this series, which replaces some queries of > BDS.filename by reads from somewhere else (mostly BDS.exact_filename), > the filename field is only used when a disk image is opened or some > message should be emitted, both of which cases do not suffer from the > performance hit.
Surprisingly (or not), this one needs rebasing. I tried it and it doesn't look too hard, but it's a little bit more than what I'm comfortable with doing while applying a series. Kevin
