GSOC 2018: Implementing blackholing in Gatekeeper

[gogapp]

This PR implements space saving algorithm in Gatekeeper.

[AltraMayor]

Implement space saving algorithm

Files .directory, generate_if_map, and lua/if_map.lua don't belong to this pull request.

[cjdoucette]

The code in include/space_saving.h and lib/space_saving.c should use tabs as indents, not spaces. We also use the DPDK style guidelines for Gatekeeper, which you can find here:

https://doc.dpdk.org/guides/contributing/coding_style.html

Make sure your code abides by these guidelines.

[cjdoucette]

Remove the extra space at the end of this line.

[gogapp]

Hi mentors,

I have added the changes that you have requested. I have also merged the commits into a single meaningful commit.

Please note that the implementation is still not fully complete and I am working on the TODOs present in the code.

[cjdoucette]

All of the case statements should be at the same level of indentation as the switch statement.

[cjdoucette]

Add a space between switch and the parenthesis.

[cjdoucette]

Same thing here: add a space and bring everything inside of this switch back one level of indentation.

[cjdoucette]

This should be declared at the top of the function, not in the middle.

[cjdoucette]

Add a space after the if and before the parenthesis. Look through the rest of the code for similar cases.

[gogapp]

I have added the code files for the final review and fixed the styling errors. For testing of the algorithms, I have created a different repository here. https://github.com/gogapp/GSOC-2018-tests

[cjdoucette]

Can you rebase your code to include one commit to add the space saving algorithm and one commit to add the RHHH algorithm? In other words, we shouldn't have a separate commit for fixing the style issues.

Also, the Gatekeeper code does not call the functions you are adding. To merge these changes we will need to have it actually integrated with Gatekeeper.

[gogapp]

I have rebased the commits as requested.

To get the changes integrated with Gatekeeper, I need to think out ways to do this. Currently I am focusing on my College Placements. I will integrate the functions with Gatekeeper as soon as I am free.

[AltraMayor]

Suggestion for where to integrate: gt_proc() at if (pkt_info.priority <= 1) {. That is, you'd feed all packets that are in accepted flows to the algorithms you implemented.