From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
To: "Burakov, Anatoly" <anatoly.burakov@intel.com>,
"dev@dpdk.org" <dev@dpdk.org>,
"Richardson, Bruce" <bruce.richardson@intel.com>
Cc: "Loftus, Ciara" <ciara.loftus@intel.com>,
"Hunt, David" <david.hunt@intel.com>
Subject: Re: [dpdk-dev] [PATCH v1 1/7] power_intrinsics: allow monitor checks inversion
Date: Wed, 23 Jun 2021 11:00:59 +0000 [thread overview]
Message-ID: <DM6PR11MB4491F20D7A128F06878E0BB99A089@DM6PR11MB4491.namprd11.prod.outlook.com> (raw)
In-Reply-To: <249f6957-0f10-926f-9f0e-5cb10fc4d2c3@intel.com>
> >>>
> >>>> Previously, the semantics of power monitor were such that we were
> >>>> checking current value against the expected value, and if they matched,
> >>>> then the sleep was aborted. This is somewhat inflexible, because it only
> >>>> allowed us to check for a specific value.
> >>>>
> >>>> This commit adds an option to reverse the check, so that we can have
> >>>> monitor sleep aborted if the expected value *doesn't* match what's in
> >>>> memory. This allows us to both implement all currently implemented
> >>>> driver code, as well as support more use cases which don't easily map to
> >>>> previous semantics (such as waiting on writes to AF_XDP counter value).
> >>>>
> >>>> Since the old behavior is the default, no need to adjust existing
> >>>> implementations.
> >>>>
> >>>> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> >>>> ---
> >>>> lib/eal/include/generic/rte_power_intrinsics.h | 4 ++++
> >>>> lib/eal/x86/rte_power_intrinsics.c | 5 ++++-
> >>>> 2 files changed, 8 insertions(+), 1 deletion(-)
> >>>>
> >>>> diff --git a/lib/eal/include/generic/rte_power_intrinsics.h b/lib/eal/include/generic/rte_power_intrinsics.h
> >>>> index dddca3d41c..1006c2edfc 100644
> >>>> --- a/lib/eal/include/generic/rte_power_intrinsics.h
> >>>> +++ b/lib/eal/include/generic/rte_power_intrinsics.h
> >>>> @@ -31,6 +31,10 @@ struct rte_power_monitor_cond {
> >>>> * 4, or 8. Supplying any other value will result in
> >>>> * an error.
> >>>> */
> >>>> + uint8_t invert; /**< Invert check for expected value (e.g. instead of
> >>>> + * checking if `val` matches something, check if
> >>>> + * `val` *doesn't* match a particular value)
> >>>> + */
> >>>> };
> >>>>
> >>>> /**
> >>>> diff --git a/lib/eal/x86/rte_power_intrinsics.c b/lib/eal/x86/rte_power_intrinsics.c
> >>>> index 39ea9fdecd..5d944e9aa4 100644
> >>>> --- a/lib/eal/x86/rte_power_intrinsics.c
> >>>> +++ b/lib/eal/x86/rte_power_intrinsics.c
> >>>> @@ -117,7 +117,10 @@ rte_power_monitor(const struct rte_power_monitor_cond *pmc,
> >>>> const uint64_t masked = cur_value & pmc->mask;
> >>>>
> >>>> /* if the masked value is already matching, abort */
> >>>> - if (masked == pmc->val)
> >>>> + if (!pmc->invert && masked == pmc->val)
> >>>> + goto end;
> >>>> + /* same, but for inverse check */
> >>>> + if (pmc->invert && masked != pmc->val)
> >>>> goto end;
> >>>> }
> >>>>
> >>>
> >>> Hmm..., such approach looks too 'patchy'...
> >>> Can we at least replace 'inver' with something like:
> >>> enum rte_power_monitor_cond_op {
> >>> _EQ, NEQ,...
> >>> };
> >>> Then at least new comparions ops can be added in future.
> >>> Even better I think would be to just leave to PMD to provide a comparison callback.
> >>> Will make things really simple and generic:
> >>> struct rte_power_monitor_cond {
> >>> volatile void *addr;
> >>> int (*cmp)(uint64_t val);
> >>> uint8_t size;
> >>> };
> >>> And then in rte_power_monitor(...):
> >>> ....
> >>> const uint64_t cur_value = __get_umwait_val(pmc->addr, pmc->size);
> >>> if (pmc->cmp(cur_value) != 0)
> >>> goto end;
> >>> ....
> >>>
> >>
> >> I like the idea of a callback, but these are supposed to be
> >> intrinsic-like functions, so putting too much into them is contrary to
> >> their goal, and it's going to make the API hard to use in simpler cases
> >> (e.g. when we're explicitly calling rte_power_monitor as opposed to
> >> letting the RX callback do it for us). For example, event/dlb code calls
> >> rte_power_monitor explicitly.
> >
> > Good point, I didn't know that.
> > Would be interesting to see how do they use it.
>
> To be fair, it should be possible to rewrite their code using a
> callback. Perhaps adding a (void *) parameter for any custom data
> related to the callback (because C doesn't have closures...), but
> otherwise it should be doable, so the question isn't that it's
> impossible to rewrite event/dlb code to use callbacks, it's more of an
> issue with complicating usage of already-not-quite-straightforward API
> even more.
>
> >
> >>
> >> It's going to be especially "fun" to do these indirect function calls
> >> from inside transactional region on call to multi-monitor.
> >
> > But the callback is not supposed to do any memory reads/writes.
> > Just mask/compare of the provided value with some constant.
>
> Yeah, but with callbacks we can't really control that, can we? I mean i
> guess a *sane* implementation wouldn't do that, but still, it's
> theoretically possible to perform more complex checks and even touch
> some unrelated data in the process.
Yep, PMD developer can ignore recommendations and do whatever
he wants in the call-back. We can't control it.
If he touches some memory in it - probably there will be more spurious wakeups and less power saves.
In principle it is the same with all other PMD dev-ops - we have to trust that they are
doing what they have to.
>
> >
> >> I'm not
> >> opposed to having a callback here, but maybe others have more thoughts
> >> on this?
> >>
> >> --
> >> Thanks,
> >> Anatoly
>
>
> --
> Thanks,
> Anatoly
next prev parent reply other threads:[~2021-06-23 11:01 UTC|newest]
Thread overview: 165+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-01 12:00 [dpdk-dev] [PATCH v1 0/7] Enhancements for PMD power management Anatoly Burakov
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 1/7] power_intrinsics: allow monitor checks inversion Anatoly Burakov
2021-06-21 12:56 ` Ananyev, Konstantin
2021-06-23 9:43 ` Burakov, Anatoly
2021-06-23 9:55 ` Ananyev, Konstantin
2021-06-23 10:00 ` Burakov, Anatoly
2021-06-23 11:00 ` Ananyev, Konstantin [this message]
2021-06-23 12:12 ` Burakov, Anatoly
2021-06-23 13:27 ` Ananyev, Konstantin
2021-06-23 14:13 ` Burakov, Anatoly
2021-06-24 9:47 ` Ananyev, Konstantin
2021-06-24 14:34 ` Burakov, Anatoly
2021-06-24 14:57 ` Ananyev, Konstantin
2021-06-24 15:04 ` Burakov, Anatoly
2021-06-24 15:25 ` Ananyev, Konstantin
2021-06-24 15:54 ` Burakov, Anatoly
2021-07-09 15:03 ` David Marchand
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-06-02 12:59 ` Loftus, Ciara
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-06-22 9:13 ` Ananyev, Konstantin
2021-06-23 9:46 ` Burakov, Anatoly
2021-06-23 9:52 ` Ananyev, Konstantin
2021-06-25 11:52 ` Burakov, Anatoly
2021-06-25 14:42 ` Ananyev, Konstantin
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-06-22 9:41 ` Ananyev, Konstantin
2021-06-23 9:36 ` Burakov, Anatoly
2021-06-23 9:49 ` Ananyev, Konstantin
2021-06-23 9:56 ` Burakov, Anatoly
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 6/7] power: support monitoring " Anatoly Burakov
2021-06-01 12:00 ` [dpdk-dev] [PATCH v1 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 0/7] Enhancements for PMD power management Anatoly Burakov
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-06-28 12:19 ` Ananyev, Konstantin
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-06-28 12:37 ` Ananyev, Konstantin
2021-06-28 12:43 ` Burakov, Anatoly
2021-06-28 12:58 ` Ananyev, Konstantin
2021-06-28 13:29 ` Burakov, Anatoly
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-06-28 7:10 ` David Marchand
2021-06-28 9:25 ` Burakov, Anatoly
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 6/7] power: support monitoring " Anatoly Burakov
2021-06-25 14:00 ` [dpdk-dev] [PATCH v2 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 0/7] Enhancements for PMD power management Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 6/7] power: support monitoring " Anatoly Burakov
2021-06-28 13:29 ` Ananyev, Konstantin
2021-06-28 14:09 ` Burakov, Anatoly
2021-06-29 0:07 ` Ananyev, Konstantin
2021-06-29 11:05 ` Burakov, Anatoly
2021-06-29 11:39 ` Burakov, Anatoly
2021-06-29 12:14 ` Ananyev, Konstantin
2021-06-29 13:23 ` Burakov, Anatoly
2021-06-28 12:41 ` [dpdk-dev] [PATCH v3 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 0/7] Enhancements for PMD power management Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 6/7] power: support monitoring " Anatoly Burakov
2021-06-28 15:54 ` [dpdk-dev] [PATCH v4 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 0/7] Enhancements for PMD power management Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-06-30 9:52 ` David Hunt
2021-07-01 9:01 ` David Hunt
2021-07-05 10:24 ` Burakov, Anatoly
2021-06-30 11:04 ` Ananyev, Konstantin
2021-07-05 10:23 ` Burakov, Anatoly
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 6/7] power: support monitoring " Anatoly Burakov
2021-06-30 10:29 ` Ananyev, Konstantin
2021-07-05 10:08 ` Burakov, Anatoly
2021-06-29 15:48 ` [dpdk-dev] [PATCH v5 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-07-05 15:21 ` [dpdk-dev] [PATCH v6 0/7] Enhancements for PMD power management Anatoly Burakov
2021-07-05 15:21 ` [dpdk-dev] [PATCH v6 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-07-05 15:21 ` [dpdk-dev] [PATCH v6 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-07-05 15:21 ` [dpdk-dev] [PATCH v6 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-08-04 9:52 ` Kinsella, Ray
2021-07-05 15:21 ` [dpdk-dev] [PATCH v6 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-07-07 10:14 ` Ananyev, Konstantin
2021-07-05 15:22 ` [dpdk-dev] [PATCH v6 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-07-06 18:50 ` Ananyev, Konstantin
2021-07-07 10:06 ` Burakov, Anatoly
2021-07-07 10:11 ` Ananyev, Konstantin
2021-07-07 11:54 ` Burakov, Anatoly
2021-07-07 12:51 ` Ananyev, Konstantin
2021-07-07 14:35 ` Burakov, Anatoly
2021-07-07 17:09 ` Ananyev, Konstantin
2021-07-07 10:04 ` David Hunt
2021-07-07 10:28 ` Burakov, Anatoly
2021-07-05 15:22 ` [dpdk-dev] [PATCH v6 6/7] power: support monitoring " Anatoly Burakov
2021-07-07 10:16 ` Ananyev, Konstantin
2021-07-05 15:22 ` [dpdk-dev] [PATCH v6 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 0/7] Enhancements for PMD power management Anatoly Burakov
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-07-07 11:56 ` David Hunt
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-07-07 12:01 ` David Hunt
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-07-07 12:02 ` David Hunt
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-07-07 11:54 ` David Hunt
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 6/7] power: support monitoring " Anatoly Burakov
2021-07-07 12:03 ` David Hunt
2021-07-07 10:48 ` [dpdk-dev] [PATCH v7 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-07-07 12:03 ` David Hunt
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 0/7] Enhancements for PMD power management Anatoly Burakov
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 1/7] power_intrinsics: use callbacks for comparison Anatoly Burakov
2021-07-08 16:56 ` McDaniel, Timothy
2021-07-09 13:46 ` Thomas Monjalon
2021-07-09 14:41 ` Burakov, Anatoly
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 2/7] net/af_xdp: add power monitor support Anatoly Burakov
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 3/7] eal: add power monitor for multiple events Anatoly Burakov
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 4/7] power: remove thread safety from PMD power API's Anatoly Burakov
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 5/7] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-07-09 14:24 ` David Marchand
2021-07-09 14:42 ` Burakov, Anatoly
2021-07-09 14:46 ` David Marchand
2021-07-09 14:53 ` Burakov, Anatoly
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 6/7] power: support monitoring " Anatoly Burakov
2021-07-08 14:13 ` [dpdk-dev] [PATCH v8 7/7] l3fwd-power: support multiqueue in PMD pmgmt modes Anatoly Burakov
2021-07-09 14:50 ` David Marchand
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 0/8] Enhancements for PMD power management Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 1/8] eal: use callbacks for power monitoring comparison Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 2/8] net/af_xdp: add power monitor support Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 3/8] doc: add PMD power management NIC feature Anatoly Burakov
2021-07-09 15:57 ` Burakov, Anatoly
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 4/8] eal: add power monitor for multiple events Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 5/8] power: remove thread safety from PMD power API's Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 6/8] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 7/8] power: support monitoring " Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 15:53 ` [dpdk-dev] [PATCH v9 8/8] examples/l3fwd-power: support multiq in PMD modes Anatoly Burakov
2021-07-09 16:00 ` Anatoly Burakov
2021-07-09 16:00 ` [dpdk-dev] [PATCH v9 0/8] Enhancements for PMD power management Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 " Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 1/8] eal: use callbacks for power monitoring comparison Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 2/8] net/af_xdp: add power monitor support Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 3/8] doc: add PMD power management NIC feature Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 4/8] eal: add power monitor for multiple events Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 5/8] power: remove thread safety from PMD power API's Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 6/8] power: support callbacks for multiple Rx queues Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 7/8] power: support monitoring " Anatoly Burakov
2021-07-09 16:08 ` [dpdk-dev] [PATCH v10 8/8] examples/l3fwd-power: support multiq in PMD modes Anatoly Burakov
2021-07-09 19:24 ` [dpdk-dev] [PATCH v10 0/8] Enhancements for PMD power management David Marchand
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=DM6PR11MB4491F20D7A128F06878E0BB99A089@DM6PR11MB4491.namprd11.prod.outlook.com \
--to=konstantin.ananyev@intel.com \
--cc=anatoly.burakov@intel.com \
--cc=bruce.richardson@intel.com \
--cc=ciara.loftus@intel.com \
--cc=david.hunt@intel.com \
--cc=dev@dpdk.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).