On Thu, Feb 1, 2018 at 12:04 PM, Stephan Mueller <smueller@xxxxxxxxxx> wrote: > Am Donnerstag, 1. Februar 2018, 10:35:07 CET schrieb Gilad Ben-Yossef: > > Hi Gilad, > >> > >> > Which works well for the sort of optimization I did and for hardware that >> > can do iv dependency tracking itself. If hardware dependency tracking was >> > avilable, you would be able to queue up requests with a chained IV >> > without taking any special precautions at all. The hardware would >> > handle the IV update dependencies. >> > >> > So in conclusion, Stephan's approach should work and give us a nice >> > small patch suitable for stable inclusion. >> > >> > However, if people know that their setup overhead can be put in parallel >> > with previous requests (even when the IV is not yet updated) then they >> > will >> > probably want to do something inside their own driver and set the flag >> > that Stephan is proposing adding to bypass the mutex approach. >> >> The patches from Stephan looks good to me, but I think we can do better >> for the long term approach you are discussing. > > What you made me think of is the following: shouldn't we relay the inline IV > flag on to the crypto drivers? > > The reason is to allow a clean implementation of the enabling or disabling of > the dependency handling in the driver. Jonathan's driver, for example, decides > based on the pointer value of the IV buffer whether it is the same buffer and > thus dependency handling is to be applied. This is fragile. > > As AF_ALG knows whether the inline IV with separate IVs per request or the > serialization with one IV buffer for all requests is requested, it should > relay this state on to the drivers. Thus, for example, Jonathan's driver can > be changed to rely on this flag instead on the buffer pointer value to decide > whether to enable its dependency handling. Yes, that is exactly what I was trying to point out :-) Thanks, Gilad -- Gilad Ben-Yossef Chief Coffee Drinker "If you take a class in large-scale robotics, can you end up in a situation where the homework eats your dog?" -- Jean-Baptiste Queru
