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 2. action_update callback is PMD specific & if it's unsupported there is no support for shared action any way 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 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.
