On Wed, Oct 28, 2020 at 9:19 PM Ananyev, Konstantin <[email protected]> wrote: > > > > > -----Original Message----- > > From: Jerin Jacob <[email protected]> > > Sent: Wednesday, October 28, 2020 3:40 PM > > To: Ananyev, Konstantin <[email protected]> > > Cc: Thomas Monjalon <[email protected]>; Ma, Liang J > > <[email protected]>; dpdk-dev <[email protected]>; Ruifeng Wang (Arm > > Technology China) <[email protected]>; Wang, Haiyue > > <[email protected]>; Richardson, Bruce > > <[email protected]>; Hunt, David <[email protected]>; Neil > > Horman <[email protected]>; McDaniel, Timothy > > <[email protected]>; Eads, Gage <[email protected]>; Marcin > > Wojtas <[email protected]>; Guy Tzalik > > <[email protected]>; Ajit Khaparde <[email protected]>; Harman > > Kalra <[email protected]>; John Daley > > <[email protected]>; Wei Hu (Xavier <[email protected]>; Ziyang Xuan > > <[email protected]>; [email protected]; Yong > > Wang <[email protected]>; [email protected] > > Subject: Re: [PATCH v10 0/9] Add PMD power mgmt > > > > On Wed, Oct 28, 2020 at 9:04 PM Ananyev, Konstantin > > <[email protected]> wrote: > > > > > > > > > > > > > > > 28/10/2020 14:49, Jerin Jacob: > > > > > > > On Wed, Oct 28, 2020 at 7:05 PM Liang, Ma <[email protected]> > > > > > > > wrote: > > > > > > > > > > > > > > > > Hi Thomas, > > > > > > > > I think I addressed all of the questions in relation to V9. I > > > > > > > > don't think I can solve the issue of a generic API on my own. > > > > > > > > From the > > > > > > Community Call last week Jerin also said that a generic was > > > > > > investigated but that a single solution wasn't feasible. > > > > > > > > > > > > > > I think, From the architecture point of view, the specific > > > > > > > functionally of UMONITOR may not be abstracted. > > > > > > > But from the ethdev callback point of view, Can it be abstracted > > > > > > > in > > > > > > > such a way that packet notification available through > > > > > > > checking interrupt status register or ring descriptor location, > > > > > > > etc by > > > > > > > the driver. Use that callback as a notification mechanism rather > > > > > > > than defining a memory-based scheme that UMONITOR expects? or > > > > > > > similar > > > > > > > thoughts on abstraction. > > > > > > > > > > I think there is probably some sort of misunderstanding. > > > > > This API is not about providing acync notification when next packet > > > > > arrives. > > > > > This is about to putting core to sleep till some event (or timeout) > > > > > happens. > > > > > From my perspective the closest analogy: cond_timedwait(). > > > > > So we need PMD to tell us what will be the address of the condition > > > > > variable > > > > > we should sleep on. > > > > > > > > > > > I agree with Jerin. > > > > > > The ethdev API is the blocking problem. > > > > > > First problem: it is not well explained in doxygen. > > > > > > Second problem: it is probably not generic enough (if we understand > > > > > > it well) > > > > > > > > > > It is an address to sleep(/wakeup) on, plus expected value. > > > > > Honestly, I can't think-up of anything even more generic then that. > > > > > If you guys have something particular in mind - please share. > > > > > > > > Current PMD callback: > > > > typedef int (*eth_get_wake_addr_t)(void *rxq, volatile void > > > > **tail_desc_addr, + uint64_t *expected, uint64_t *mask, uint8_t > > > > *data_sz); > > > > > > > > Can we make it as > > > > typedef void (*core_sleep_t)(void *rxq) > > > > > > > > if we do such abstraction and "move the polling on memory by HW/CPU" > > > > to the driver using a helper function then > > > > I can think of abstracting in some way in all PMDs. > > > > > > Ok I see, thanks for explanation. > > > From my perspective main disadvantage of such approach - > > > it can't be extended easily. > > > If/when will have an ability for core to sleep/wake-up on multiple events > > > (multiple addresses) will have to either rework that API again. > > > > I think, we can enumerate the policies and pass the associated > > structures as input to the driver. > > What I am trying to say: with that API we will not be able to wait > for events from multiple devices (HW queues). > I.E. something like that: > > get_wake_addr(port=X, ..., &addr[0], ...); > get_wake_addr(port=Y,..., &addr[1],...); > wait_on_multi(addr, 2); > > wouldn't be possible.
I see. But the current implementation dictates the only queue bound to a core. Right? > > > > > > > > > > > > > > > > Note: core_sleep_t can take some more arguments such as enumerated > > > > policy if something more needs to be pushed to the driver. > > > > > > > > Thoughts? > > > > > > > > > > > > > > > > > > > > > > > This API is experimental and other vendor support can be added > > > > > > > > as needed. If there are any other open issue let me know? > > > > > > > > > > > > Being experimental is not an excuse to throw something > > > > > > which is not satisfying. > > > > > > > > > > > > > > > > >
