On 8/30/22 18:05, Paul Menzel wrote: > Dear Damien, > > > Sorry for the late reply, and thank you for your great work. > > Am 01.06.22 um 10:58 schrieb Damien Le Moal: >> On 6/1/22 01:18, Paul Menzel wrote: >>>>>> With that in mind, I am not planning to apply your previous patches >>>>>> for 5.18, as they would conflict and would only end up being churn >>>>>> since the delay removal by default will undo your changes. >>>>> Obviously, I do not agree, as this would give the a little bit more >>>>> testing already, if changing the default is a good idea. Also, if the >>>>> conflict will be hard to resolve, I happily do it (the patches could >>>>> even be reverted on top – git commits are cheap and easy to handle). >>>> >>>> The conflict is not hard to resolve. The point is that my patches changing >>>> the default to no debounce delay completely remove the changes of your >>>> patch to do the same for one or some adapters. So adding your patches now >>>> and then my patches on top does not make much sense at all. >>>> >>>> If too many problems show up and I end up reverting/removing the patches, >>>> then I will be happy to take your patches for the adapter you tested. Note >>>> that *all* the machines I have tested so far are OK without a debounce >>>> delay too. So we could add them too... And endup with a long list of >>>> adapters that use the default ahci driver without debounce delay. The goal >>>> of changing the default to no delay is to avoid that. So far, the adapters >>>> I have identified that need the delay have their own declaration, so we >>>> only need to add a flag there. Simpler change that listing up adapters >>>> that are OK without the delay. >>>> >>>>> Anyway, I wrote my piece, but you are the maintainer, so it’s your call >>>>> and I stop bothering you. >>> >>> I just wanted to inquire about the status of your changes? I do not find >>> them in your `for-5.19` branch. As they should be tested in linux-next >>> before the merge window opens, if these are not ready yet, could you >>> please apply my (tested) patches? >> >> I could, but 5.19 now has an updated libata.force kernel parameter that >> allows one to disable the debounce delay for a particular port or for all >> ports of an adapter. See libata.force=x.y:nodbdelay for a port y of >> adapter x or libata.force=x:nodbdelay for all ports of adapter x. > > This is commit 3af9ca4d341d (ata: libata-core: Improve link flags forced > settings) [1]. Thank you, this is really useful, but easily overlooked. ;-) > >> I still plan to revisit the arbitrary link debounce timers but I prefer to >> have the power management cleanup applied first. The reason is that link >> debounce depends on PHY readiness, which itself depends heavily on power >> mode transitions. My plan is to get this done during this cycle for >> release with 5.20 and then fix on top the arbitrary delays for 5.21. > > Nice. Can you share the current status? No progress. I need to put together a series with all the patches that were sent already. Unless Mario can resend something ? >> Is the libata.force solution OK for you until we have a final more solid >> fix that can benefit most modern adapters (and not just the ones you >> identified)? If you do have a use case that needs a "nodbdelay" horkage >> due to some constraint in the field, then I will apply your patches, but >> they likely will be voided by coming changes. Let me know. > > I think, applying the patch would be an improvement, as people wouldn’t > need to update their Linux kernel command line, and I do not mind, if it > gets reverted/dropped later. Let's see were the lpm stuff goes first. -- Damien Le Moal Western Digital Research
