[PAL/vm-common] vsock: add guest-side vsock buf management #26
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
dimakuv
force-pushed
the
dimakuv/vsock-add-guest-buf-management
branch
from
139c9ee to
f78afce
Compare
dimakuv
force-pushed
the
dimakuv/vsock-add-guest-buf-management
branch
from
f78afce to
b798656
Compare
The guest (our Gramine) should use `tx_cnt`, `peer_fwd_cnt` and `peer_buf_alloc` to calculate the number of bytes currently available in the host buffer, and thus currently possible for Gramine to send on a particular connection (particular virtual socket). Previously, we didn't implement this guest-side buffer space management which could lead to app's select/poll/epoll incorrectly returning POLLOUT events. This commit fixes this by implementing guest-side buffer space management as outlined by the virtio spec. Signed-off-by: Dmitrii Kuvaiskii <[email protected]>
dimakuv
force-pushed
the
dimakuv/vsock-add-guest-buf-management
branch
from
b798656 to
5e8a17f
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description of the changes
The guest (our Gramine) should use
tx_cnt,peer_fwd_cntandpeer_buf_allocto calculate the number of bytes currently available in the host buffer, and thus currently possible for Gramine to send on a particular connection (particular virtual socket). Previously, we didn't implement this guest-side buffer space management which could lead to app's select/poll/epoll incorrectly returning POLLOUT events.This commit fixes this by implementing guest-side buffer space management as outlined by the virtio spec.
How to test this PR?
Actually, Redis and Memcached seem to not use this (i.e., don't perform
poll(..., POLLOUT)). So I couldn't really test it, only in my head.This change is