[Skiboot] [PATCH 06/12] hiomap: Enable Async IPMI messaging

[Oliver O'Halloran]

On Fri, Oct 18, 2019 at 8:57 AM Deb McLemore <debmc at linux.ibm.com> wrote:
>
> To provide higher layer async operations to access
> the target flash, enable hiomap to perform async
> ipmi messaging for call paths thru opal_flash_op.
>
> Special considerations and constraints are to prevent
> recursive locking and/or polling inside OPAL calls.
>
> Objective is to remove the hiomap_queue_msg_sync for
> moving windows (which already uses pollers) to allow
> async requests to perform their functions.
>
> Call paths thru opal_flash_op will determine if the
> requested operation needs to be re-queued, to allow
> skiboot to jump back out to Linux to prevent RCU or
> scheduler issues.
>
> PR_TRACE used since PR_DEBUG seems to always trigger,
> unable to figure out why.

Probably because of that loglevel bug that's existed forever. I wrote
some patches to fix it years ago and the never went anywhere for
reasons that are probably stupid. Feel free to dust them off.

http://patchwork.ozlabs.org/bundle/oohal/loglevel/?series=&submitter=&state=*&q=&archive=both

>
> Signed-off-by: Deb McLemore <debmc at linux.ibm.com>
> ---
>  core/flash.c           | 142 +++++++-
>  libflash/blocklevel.h  |   5 +
>  libflash/errors.h      |   1 +
>  libflash/ipmi-hiomap.c | 938 ++++++++++++++++++++++++++++++++++++++-----------
>  libflash/ipmi-hiomap.h |  37 +-
>  5 files changed, 903 insertions(+), 220 deletions(-)

I'm not going to review this in detail until you make the patch
actually reviewable. Move the additional debug prints into separate
patches and try factor out some of the common parts into helper
functions or wrappers, similar to what we do with PHBERR() and
friends.

Also can you use block comments for block comments and not:
/* this */
/* stuff */