On Mon, Jun 29, 2020 at 3:52 PM Andrey Vesnovaty <andrey.vesnov...@gmail.com> wrote: > > > > On Sun, Jun 28, 2020 at 4:42 PM Jerin Jacob <jerinjac...@gmail.com> wrote: >> >> On Sun, Jun 28, 2020 at 2:14 PM Andrey Vesnovaty >> <andrey.vesnov...@gmail.com> wrote: >> > >> > Hi >> > >> > On Fri, Jun 26, 2020 at 2:44 PM Jerin Jacob <jerinjac...@gmail.com> wrote: >> >> >> >> On Sat, Jun 20, 2020 at 7:02 PM Andrey Vesnovaty >> >> <andrey.vesnov...@gmail.com> wrote: >> >> > >> >> > Hi, and thanks a lot for your RFC v1 comments. >> >> > >> >> > RFC v2 emphasize the intent for sharing the flow action: >> >> > * The term 'action context' was unclear and replaced with >> >> > 'shared action'. >> >> > * RFC v2 subject became 'add flow shared action API'. >> >> > * all proposed APIs renamed according the above. >> >> > >> >> > The new shared action is an independent entity decoupled from any flow >> >> > while any flow can reuse such an action. Please go over the RFC >> >> > description, it was almost entirely rewritten. >> >> > >> >> > @Jerin Jacob: >> >> > Thanks again for your comments, it made me admit that v1 description was >> >> > incomplete & unclear. I hope v2 will be better at least in terms of >> >> > clarity. >> >> >> >> The public API and its usage is very clear. Thanks for this RFC. >> > >> > >> > My pleasure. >> >> >> >> >> >> I think, RFC v2 still not addressing the concern raised in the >> >> http://mails.dpdk.org/archives/dev/2020-June/169296.html. >> >> >> >> Since MLX hardware has an HW based shared object it is fine to have >> >> public API based on that level of abstraction. >> >> But at the PMD driver level we need to choose the correct abstraction >> >> to support all PMD and support shared object scheme if possible. >> >> >> >> I purpose to introduce something below or similar >> >> int (*action_update) >> >> (struct rte_eth_dev *, >> >> struct rte_flow *flow, >> >> const struct rte_flow_action [], >> >> struct rte_flow_error *); >> > >> > Where this callback suppose to belong (struct rte_flow_ops)? >> >> Yes. >> >> > How should it be implemented by PMD? >> >> See below, >> >> > Is it about shared action and if "yes" why there is 'flow' argument? >> >> flow holds the "pattern" and "action" data as PMD specific handle. >> So PMD, implementation can just change that action if it gets the PMD >> specific handle. >> >> >> >> >> >> >> >> in addition to: shared_action_create, shared_action_destroy, >> >> shared_action_update, shared_action_query >> >> >> >> Have generic implementation of above, if action_update callback is not >> >> NULL. >> > >> > "is not NULL" -> "is NULL"? >> >> Yes. When it is NULL. > > > Jerin, few clarifications regarding generic implementation of shared action: > Based on this conversation I'm assuming that generic implementation supposed > to be something like: > For each flow using some shared action: > call ops-> action_update() > If the assumption above correct: > 1. taking into account that shared_action_update() is atomic, how can this > deal with partial success: some flows may fail validation - should it: > 1.1.lock all flows > 1.2.validate all flows > 1.3.update all flows > 1.4. unlock
Yes. > 2. action_update callback is PMD specific & if it's unsupported there is no > support for shared action any way Yes. > Please address the issues above > >> > >> >> >> >> So that, it can work all PMDs and to >> >> avoid the duplication of "complex" shared session management code. >> > >> > Do you mean shared action in use by multiple flows by "shared session"? >> >> Yes. > > Common 'shared session' management code: > - can be reduced to atomic usage counter > - maintaining list of flow using shared action expected to impact performance > & not necessary for all PMD specific implementations > Access to other shared resources hard to generalize because: > - for some PMDs mutual exclusion is HW feature & no need to protect it in SW > - for others there may be multiple resources & access to each one protected > by different mechanism The general callback you can assume, it supports only action_update based callback. If PMD has mutual exclusion HW feature then it can override the function pointers. > An observation related to action_update callback: > If replaced (updated) action was shared then the flow won't be influenced any > more by updates or removed shared action.
