| Message ID | 20210120201241.GR1227584@habkost.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | docs/system: Deprecate `-cpu ...,+feature,-feature` syntax | expand |
On Wednesday, 2021-01-20 at 15:12:41 -05, Eduardo Habkost wrote: > The ordering semantics of +feature/-feature is tricky and not > obvious, and it requires a custom option parser. Deprecate that > syntax so we can eventually remove the custom -cpu option parser > and plus_features/minus_features global variables in i386. > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> With very minor wording comment... Reviewed-by: David Edmondson <david.edmondson@oracle.com> > --- > docs/system/deprecated.rst | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst > index e20bfcb17a4..2c4b8d4b78b 100644 > --- a/docs/system/deprecated.rst > +++ b/docs/system/deprecated.rst > @@ -127,6 +127,20 @@ Drives with interface types other than ``if=none`` are for onboard > devices. It is possible to use drives the board doesn't pick up with > -device. This usage is now deprecated. Use ``if=none`` instead. > > +``-cpu`` ``+feature`` and ``-feature`` syntax (since 6.0.0) > +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' > + > +The ``-cpu ...,+feature`` and ``-cpu ...,-feature`` syntax for > +enabling and disabling CPU features is deprecated. The ``-cpu > +...,feature=on`` or ``-cpu ...,feature=off`` should be used > +instead. > + > +Note that the ordering semantics of ``-cpu ...,-feature,+feature`` > +is different from ``-cpu ...,feature=off,feature=on``. With the > +former, the feature got disabled because ``-feature`` had s/got/was/ > +precedence, but with the latter the feature will be enabled > +because options are applied in the order they appear. > + > > QEMU Machine Protocol (QMP) commands > ------------------------------------ > -- > 2.28.0 dme.
On Wed, Jan 20, 2021 at 03:12:41PM -0500, Eduardo Habkost wrote: > The ordering semantics of +feature/-feature is tricky and not > obvious, and it requires a custom option parser. Deprecate that > syntax so we can eventually remove the custom -cpu option parser > and plus_features/minus_features global variables in i386. > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > --- > docs/system/deprecated.rst | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) Ideally we would also print a warning on stderr when this deprecated style is used. > > diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst > index e20bfcb17a4..2c4b8d4b78b 100644 > --- a/docs/system/deprecated.rst > +++ b/docs/system/deprecated.rst > @@ -127,6 +127,20 @@ Drives with interface types other than ``if=none`` are for onboard > devices. It is possible to use drives the board doesn't pick up with > -device. This usage is now deprecated. Use ``if=none`` instead. > > +``-cpu`` ``+feature`` and ``-feature`` syntax (since 6.0.0) > +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' > + > +The ``-cpu ...,+feature`` and ``-cpu ...,-feature`` syntax for > +enabling and disabling CPU features is deprecated. The ``-cpu > +...,feature=on`` or ``-cpu ...,feature=off`` should be used > +instead. > + > +Note that the ordering semantics of ``-cpu ...,-feature,+feature`` > +is different from ``-cpu ...,feature=off,feature=on``. With the > +former, the feature got disabled because ``-feature`` had > +precedence, but with the latter the feature will be enabled > +because options are applied in the order they appear. > + Regards, Daniel
On Wed, 20 Jan 2021 15:12:41 -0500 Eduardo Habkost <ehabkost@redhat.com> wrote: > The ordering semantics of +feature/-feature is tricky and not > obvious, and it requires a custom option parser. Deprecate that > syntax so we can eventually remove the custom -cpu option parser > and plus_features/minus_features global variables in i386. it affects spark as well with that Reviewed-by: Igor Mammedov <imammedo@redhat.com> > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > --- > docs/system/deprecated.rst | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst > index e20bfcb17a4..2c4b8d4b78b 100644 > --- a/docs/system/deprecated.rst > +++ b/docs/system/deprecated.rst > @@ -127,6 +127,20 @@ Drives with interface types other than ``if=none`` are for onboard > devices. It is possible to use drives the board doesn't pick up with > -device. This usage is now deprecated. Use ``if=none`` instead. > > +``-cpu`` ``+feature`` and ``-feature`` syntax (since 6.0.0) > +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' > + > +The ``-cpu ...,+feature`` and ``-cpu ...,-feature`` syntax for > +enabling and disabling CPU features is deprecated. The ``-cpu > +...,feature=on`` or ``-cpu ...,feature=off`` should be used > +instead. > + > +Note that the ordering semantics of ``-cpu ...,-feature,+feature`` > +is different from ``-cpu ...,feature=off,feature=on``. With the > +former, the feature got disabled because ``-feature`` had > +precedence, but with the latter the feature will be enabled > +because options are applied in the order they appear. > + > > QEMU Machine Protocol (QMP) commands > ------------------------------------
On 1/21/21 4:39 AM, Daniel P. Berrangé wrote: > On Wed, Jan 20, 2021 at 03:12:41PM -0500, Eduardo Habkost wrote: >> The ordering semantics of +feature/-feature is tricky and not >> obvious, and it requires a custom option parser. Deprecate that >> syntax so we can eventually remove the custom -cpu option parser >> and plus_features/minus_features global variables in i386. >> >> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> >> --- >> docs/system/deprecated.rst | 14 ++++++++++++++ >> 1 file changed, 14 insertions(+) > > Ideally we would also print a warning on stderr when this deprecated > style is used. > +1. It might break some tests to do that, though, but if it's not too gruesome it's probably worth it.
diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index e20bfcb17a4..2c4b8d4b78b 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -127,6 +127,20 @@ Drives with interface types other than ``if=none`` are for onboard devices. It is possible to use drives the board doesn't pick up with -device. This usage is now deprecated. Use ``if=none`` instead. +``-cpu`` ``+feature`` and ``-feature`` syntax (since 6.0.0) +''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The ``-cpu ...,+feature`` and ``-cpu ...,-feature`` syntax for +enabling and disabling CPU features is deprecated. The ``-cpu +...,feature=on`` or ``-cpu ...,feature=off`` should be used +instead. + +Note that the ordering semantics of ``-cpu ...,-feature,+feature`` +is different from ``-cpu ...,feature=off,feature=on``. With the +former, the feature got disabled because ``-feature`` had +precedence, but with the latter the feature will be enabled +because options are applied in the order they appear. + QEMU Machine Protocol (QMP) commands ------------------------------------
The ordering semantics of +feature/-feature is tricky and not obvious, and it requires a custom option parser. Deprecate that syntax so we can eventually remove the custom -cpu option parser and plus_features/minus_features global variables in i386. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> --- docs/system/deprecated.rst | 14 ++++++++++++++ 1 file changed, 14 insertions(+)