From: "Daniel P. Berrangé" <berrange@redhat.com>
To: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: Stefan Weil <sw@weilnetz.de>, Thomas Huth <thuth@redhat.com>,
Richard Henderson <richard.henderson@linaro.org>,
qemu-devel@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v3 2/4] meson: Warn when TCI is selected but TCG backend is available
Date: Mon, 25 Jan 2021 09:50:49 +0000 [thread overview]
Message-ID: <20210125095049.GC3527172@redhat.com> (raw)
In-Reply-To: <20210122133004.1913923-3-philmd@redhat.com>
On Fri, Jan 22, 2021 at 02:30:02PM +0100, Philippe Mathieu-Daudé wrote:
> Some new users get confused with 'TCG' and 'TCI', and enable TCI
> support expecting to enable TCG.
>
> Emit a warning when native TCG backend is available on the
> host architecture, mentioning this is a suboptimal configuration.
>
> Reviewed-by: Stefan Weil <sw@weilnetz.de>
> Reviewed-by: Thomas Huth <thuth@redhat.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> meson.build | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/meson.build b/meson.build
> index d5b76150e49..d3df5fa3516 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -234,6 +234,9 @@
> error('Unsupported CPU @0@, try --enable-tcg-interpreter'.format(cpu))
> endif
> endif
> + if 'CONFIG_TCG_INTERPRETER' in config_host and cpu in supported_cpus
> + warning('Experimental TCI requested while native TCG is available on @0@, suboptimal performance expected'.format(cpu))
> + endif
warning('Use of the TCG interpretor is not recommended on this host
architecture. There is a native TCG execution backend available
which provides substantially better performance and reliability.
It is strongly recommended to remove the --enable-tcg-interpreter
configuration option on this architecture to use the native
backend.')
Regards,
Daniel
--
|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org -o- https://fstop138.berrange.com :|
|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
next prev parent reply other threads:[~2021-01-25 9:53 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-22 13:30 [PATCH v3 0/4] meson: Try to clarify TCG / TCI options for new users Philippe Mathieu-Daudé
2021-01-22 13:30 ` [PATCH v3 1/4] meson: Explicit TCG backend used Philippe Mathieu-Daudé
2021-01-22 13:30 ` [PATCH v3 2/4] meson: Warn when TCI is selected but TCG backend is available Philippe Mathieu-Daudé
2021-01-25 9:50 ` Daniel P. Berrangé [this message]
2021-01-22 13:30 ` [PATCH v3 3/4] configure: Improve TCI feature description Philippe Mathieu-Daudé
2021-01-22 13:30 ` [PATCH v3 4/4] configure: Reword --enable-tcg-interpreter as --disable-native-tcg Philippe Mathieu-Daudé
2021-01-23 18:13 ` Paolo Bonzini
2021-01-24 15:49 ` Philippe Mathieu-Daudé
2021-01-23 18:13 ` [PATCH v3 0/4] meson: Try to clarify TCG / TCI options for new users Paolo Bonzini
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=20210125095049.GC3527172@redhat.com \
--to=berrange@redhat.com \
--cc=pbonzini@redhat.com \
--cc=philmd@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=richard.henderson@linaro.org \
--cc=sw@weilnetz.de \
--cc=thuth@redhat.com \
/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).