On 15/10/2024 08:11, Philipp Stanner wrote:
On Mon, 2024-10-14 at 13:07 +0100, Tvrtko Ursulin wrote:
On 14/10/2024 12:32, Philipp Stanner wrote:
Hi,
On Mon, 2024-10-14 at 11:46 +0100, Tvrtko Ursulin wrote:
From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxx>
In FIFO mode We can avoid dropping the lock only to immediately
re-
acquire
by adding a new drm_sched_rq_update_fifo_locked() helper.
Please write detailed commit messages, as described here [1].
1. Describe the problem: current state and why it's bad.
2. Then, describe in imperative (present tense) form what the
commit
does about the problem.
Both pieces of info are already there:
1. Drops the lock to immediately re-acquire it.
2. We avoid that by by adding a locked helper.
Optionally, in between can be information about why it's solved
this
way and not another etc.
Applies to the other patches, too.
[1]
https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes
Thanks I am new here and did not know this.
Seriosuly, lets not be too blindly strict about this because it can
get
IMO ridiculous.
One example when I previously accomodated your request is patch 3/5
from
this series:
"""
Current kerneldoc for struct drm_sched_rq incompletely documents what
fields are protected by the lock.
This is not good because it is misleading.
Lets fix it by listing all the elements which are protected by the
lock.
"""
While this was the original commit text you weren't happy with:
"""
drm/sched: Re-order struct drm_sched_rq members for clarity
Lets re-order the members to make it clear which are protected by the
lock
and at the same time document it via kerneldoc.
"""
I maintain the original text was passable.
On top, this was just a respin to accomodate the merge process. All
approvals were done and dusted couple weeks or so ago so asking for
yet
another respin for such trivial objections is not great.
I understand that you're unhappy, but please understand the position
I'm coming from. As you know, since you sent these patches within a
different series (and, thus, since I reviewed them), I was trusted with
co-maintaining this piece of shared infrastructure.
And since you've worked on it a bit now, I suppose you also know that
the GPU Scheduler is arguably in quite a bad shape, has far too little
documentation, has leaks, maybe race conditions, parts *where the
locking rules are unclear* and is probably only fully understood by a
small hand full of people. I also argue that this is a *very*
complicated piece of software.
We already went over that and agreed. Not least I agreed the base is
shaky since few years ago. :)
Btw if things align, I hope you will at some point see a follow up
series from me which makes some significant simplifications and
improvements at the same time.
So I might be or appear to be a bit pedantic, but I'm not doing that to
terrorize you, but because I want this thing to become well documented,
understandable, and bisectable. Working towards a canonical, idiot-
proof commit style is one measure that will help with that.
I want to offer you the following: I can be more relaxed with things
universally recognized as trivial (comment changes, struct member
reordering) – but when something like a lock is touched in any way, we
shall document that in the commit message as canonically as possible,
so someone who's less experienced and just bisected the commit
immediately understands what has been done (or rather: was supposed to
be done).
So how would you suggest to expand this commit text so it doesn't read
too self-repeating?
Regards,
Tvrtko
