From: Peter Xu <peterx@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>,
"Daniel P . Berrange" <berrange@redhat.com>,
"Christian Borntraeger" <borntraeger@de.ibm.com>,
"Fam Zheng" <famz@redhat.com>, "Kevin Wolf" <kwolf@redhat.com>,
"Max Reitz" <mreitz@redhat.com>,
peterx@redhat.com, "Eric Auger" <eric.auger@redhat.com>,
"Eric Blake" <eblake@redhat.com>, "John Snow" <jsnow@redhat.com>,
"Markus Armbruster" <armbru@redhat.com>,
"Peter Maydell" <peter.maydell@linaro.org>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>
Subject: [Qemu-devel] [RFC v2 1/4] docs: mention shared state protect for OOB
Date: Thu, 31 May 2018 13:16:38 +0800 [thread overview]
Message-ID: <20180531051641.8473-2-peterx@redhat.com> (raw)
In-Reply-To: <20180531051641.8473-1-peterx@redhat.com>
Out-Of-Band handlers need to protect shared state if there is any.
Mention it in the document.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
docs/devel/qapi-code-gen.txt | 3 +++
1 file changed, 3 insertions(+)
diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt
index b9b6eabd08..aafc15f100 100644
--- a/docs/devel/qapi-code-gen.txt
+++ b/docs/devel/qapi-code-gen.txt
@@ -680,6 +680,9 @@ OOB command handlers must satisfy the following conditions:
- It does not invoke system calls that may block,
- It does not access guest RAM that may block when userfaultfd is
enabled for postcopy live migration.
+- It needs to protect possilbe shared states, since as long as a
+ command supports Out-Of-Band it means the handler can be run in
+ parallel with the same handler running in the other thread.
If in doubt, do not implement OOB execution support.
--
2.17.0
next prev parent reply other threads:[~2018-05-31 5:16 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-31 5:16 [Qemu-devel] [RFC v2 0/4] monitor: enable OOB by default Peter Xu
2018-05-31 5:16 ` Peter Xu [this message]
2018-05-31 14:06 ` [Qemu-devel] [RFC v2 1/4] docs: mention shared state protect for OOB Eric Blake
2018-06-07 8:06 ` Peter Xu
2018-05-31 5:16 ` [Qemu-devel] [RFC v2 2/4] tests: iotests: don't compare SHUTDOWN event Peter Xu
2018-05-31 14:42 ` Eric Blake
2018-06-04 4:59 ` Peter Xu
2018-06-04 8:10 ` Peter Xu
2018-05-31 5:16 ` [Qemu-devel] [RFC v2 3/4] monitor: remove "x-oob", turn oob on by default Peter Xu
2018-05-31 14:44 ` Eric Blake
2018-06-07 8:08 ` Peter Xu
2018-06-07 11:40 ` Markus Armbruster
2018-06-08 6:32 ` Peter Xu
2018-05-31 5:16 ` [Qemu-devel] [RFC v2 4/4] Revert "tests: Add parameter to qtest_init_without_qmp_handshake" Peter Xu
2018-05-31 14:51 ` Eric Blake
2018-06-07 8:13 ` Peter Xu
2018-05-31 5:20 ` [Qemu-devel] [RFC v2 0/4] monitor: enable OOB by default Peter Xu
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=20180531051641.8473-2-peterx@redhat.com \
--to=peterx@redhat.com \
--cc=armbru@redhat.com \
--cc=berrange@redhat.com \
--cc=borntraeger@de.ibm.com \
--cc=dgilbert@redhat.com \
--cc=eblake@redhat.com \
--cc=eric.auger@redhat.com \
--cc=famz@redhat.com \
--cc=jsnow@redhat.com \
--cc=kwolf@redhat.com \
--cc=marcandre.lureau@redhat.com \
--cc=mreitz@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.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).