[PATCH 2/3] cmd: add maximum boot option index Kconfig option

[Masahisa Kojima]

Hi Jerome,

On Wed, 23 Nov 2022 at 19:57, Jerome Forissier
<jerome.forissier at linaro.org> wrote:
>
> Hi,
>
> On 11/23/22 08:17, Masahisa Kojima wrote:
> > eficonfig command reads the all possible UEFI boot options
> > from 0x0000 to 0xFFFF to construct the menu. This takes too much
> > time in some environment, especially for the platform using
> > OP-TEE and RPMB based secure storage.
> > For example, on Socionext Developerbox, it takes more than 30 seconds
> > to draw the boot option menu.
>
> How are you configuring the RPMB FS driver in OP-TEE [1]?
> CFG_RPMB_FS_RD_ENTRIES and CFG_RPMB_FS_CACHE_ENTRIES affect how OP-TEE
> reads and caches the File Allocation Table from RPMB, they have an
> impact on the performance of file lookup. The default values are quite
> conservative in terms of memory, with no caching and a read buffer
> capable of holding entries for 8 files only. This can result is poor
> performance but was considered a reasonable default considering
> memory-constrained platforms.
>
> Since Developerbox has lots of RAM, I suggest experimenting with larger
> values. For the initial file enumeration, I think increasing
> CFG_RPMB_FS_RD_ENTRIES should be enough to improve the situation quite
> a bit. Subsequent enumerations and access to the file contents could be
> improved by also increasing CFG_RPMB_FS_CACHE_ENTRIES. I would recommend
> setting both to the same "rather large" value (128?). You might need
> to increase the TEE core heap size though (CFG_CORE_HEAP_SIZE).
>
> Then it would be nice to have these values defined as platform defaults
> upstream rather than in some downstream fork of OP-TEE (I am saying this
> because I suppose you already have custom values as part of some Yocto
> build or something).

Yes, I'm using default configuration.
Thank you for the information to improve the performance.
The problem I'm facing will be addressed by Heinrich's comment(using
GetNextVariableName()),
but OP-TEE configuration is worth trying.

Thanks,
Masahisa Kojima

>
> [1] https://github.com/OP-TEE/optee_os/blob/master/mk/config.mk#L170-L201
>
> Thanks,
> --
> Jerome