Luca Fancellu writes ("[PATCH-4.16] arm/efi: Improve performance requesting
filesystem handle"):
> Currently, the code used to handle and possibly load from the filesystem
> modules defined in the DT is allocating and closing the filesystem handle
> for each module to be loaded.
>
> To improve the performance, the filesystem handle pointer is passed
> through the call stack, requested when it's needed only once and closed
> if it was allocated.
Thsnks for submitting this formally. The clarity is very helpful.
> Signed-off-by: Luca Fancellu <[email protected]>
> ---
> Justification for integration in 4.16:
> Upside: Fixes a performance issue only on arm that would be really useful
> for ARM users using the release, no functional changes.
The size of this perf issue is not discussed here. At this stage of
the release I will usually give release acks for fixes to serious
problems. Does this meet that test ? I think probably not.
Thanks to Bertrand who, when I asked on IRC, confirmed that this perf
issue only affects users of the new feature in a1743fc3a9 (so is not a
regression), and the perf issue is only a consquenceof 9bc9fff04ba0
which was itself a fix to something wrong with a1743fc3a9. It seems
that one interpretation is that the problem here is simply a
less-than-optimal new feature.
> Downside: It's affecting the EFI boot path (only on ARM).
> Risk: Risk is low given the small changes.
I did find this risk analysis at all convincing, I'm afraid.
So I'm afraid I'm saying "no".
Ian.
