From: Peter Maydell <peter.maydell@linaro.org>
To: qemu-devel@nongnu.org, qemu-trivial@nongnu.org
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Subject: [PATCH] osdep.h: Add doc comment for qemu_get_thread_id()
Date: Thu, 16 Jul 2020 16:41:14 +0100 [thread overview]
Message-ID: <20200716154114.10838-1-peter.maydell@linaro.org> (raw)
Add a documentation comment for qemu_get_thread_id(): since this
is rather host-OS-specific it's useful if people writing the
implementation and people thinking of using the function know
what the purpose and limitations are.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
Based on conversation with Dan on IRC, and prompted by the recent
patch to add OpenBSD support.
Q: should we document exactly what the thread-id value is for
each host platform in the QMP documentation ? Somebody writing
a management layer app should ideally not have to grovel through
the application to figure out what they should do with the
integer value they get back from query-cpus...
include/qemu/osdep.h | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 4841b5c6b5f..8279f72e5ed 100644
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -515,6 +515,20 @@ bool qemu_has_ofd_lock(void);
bool qemu_write_pidfile(const char *pidfile, Error **errp);
+/**
+ * qemu_get_thread_id: Return OS-specific ID of current thread
+ *
+ * This function returns an OS-specific identifier of the
+ * current thread. This will be used for the "thread-id" field in
+ * the response to the QMP query-cpus and query-iothreads commands.
+ * The intention is that a VM management layer application can then
+ * use it to tie specific QEMU vCPU and IO threads to specific host
+ * CPUs using whatever the host OS's CPU affinity setting API is.
+ * New implementations of this function for new host OSes should
+ * return the most sensible integer ID that works for that purpose.
+ *
+ * This function should not be used for anything else inside QEMU.
+ */
int qemu_get_thread_id(void);
#ifndef CONFIG_IOVEC
--
2.20.1
next reply other threads:[~2020-07-16 15:42 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-16 15:41 Peter Maydell [this message]
2020-07-28 15:02 ` [PATCH] osdep.h: Add doc comment for qemu_get_thread_id() Peter Maydell
2020-07-28 15:16 ` Eric Blake
2020-07-28 15:25 ` Peter Maydell
2020-07-30 15:10 ` Markus Armbruster
2020-07-30 15:52 ` Peter Maydell
2020-07-30 15:59 ` Daniel P. Berrangé
2020-07-30 16:24 ` Eric Blake
2020-07-30 16:40 ` Daniel P. Berrangé
2020-07-31 7:44 ` Markus Armbruster
2020-07-31 13:46 ` Eric Blake
2020-07-31 13:51 ` Daniel P. Berrangé
2020-10-12 15:33 [PATCH 00/10] target/arm: Various v8.1M minor features Peter Maydell
2020-10-12 15:33 ` [PATCH] osdep.h: Add doc comment for qemu_get_thread_id() Peter Maydell
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=20200716154114.10838-1-peter.maydell@linaro.org \
--to=peter.maydell@linaro.org \
--cc=berrange@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=qemu-trivial@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).