Re: [PATCH qom-cpu 2/7] target-i386: Don't set any KVM flag by default if KVM is disabled
On Mon, 7 Jan 2013 16:20:43 -0200
Eduardo Habkost ehabk...@redhat.com wrote:
This is a cleanup that tries to solve two small issues:
- We don't need a separate kvm_pv_eoi_features variable just to keep a
constant calculated at compile-time, and this style would require
adding a separate variable (that's declared twice because of the
CONFIG_KVM ifdef) for each feature that's going to be enabled/disable
by machine-type compat code.
- The pc-1.3 code is setting the kvm_pv_eoi flag on cpuid_kvm_features
even when KVM is disabled at runtime. This small incosistency in
the cpuid_kvm_features field isn't a problem today because
cpuid_kvm_features is ignored by the TCG code, but it may cause
unexpected problems later when refactoring the CPUID handling code.
This patch eliminates the kvm_pv_eoi_features variable and simply uses
kvm_enabled() inside the enable_kvm_pv_eoi() compat function, so it
enables kvm_pv_eoi only if KVM is enabled. I believe this makes the
behavior of enable_kvm_pv_eoi() clearer and easier to understand.
Subj doesn't match what patch actually does.
Have you meant Don't set kvm_pv_eoi flag by default if KVM is disabled?
Although eliminate kvm_pv_eoi_features variable might better describe what
patch is doing.
Signed-off-by: Eduardo Habkost ehabk...@redhat.com
---
Cc: kvm@vger.kernel.org
Cc: Michael S. Tsirkin m...@redhat.com
Cc: Gleb Natapov g...@redhat.com
Cc: Marcelo Tosatti mtosa...@redhat.com
Changes v2:
- Coding style fix
Changes v3:
- Eliminate #ifdef by using the fake KVM_FEATURE_PV_EOI #define
---
target-i386/cpu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 951e206..40400ac 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -164,15 +164,15 @@ static uint32_t kvm_default_features = (1
KVM_FEATURE_CLOCKSOURCE) | (1 KVM_FEATURE_ASYNC_PF) |
(1 KVM_FEATURE_STEAL_TIME) |
(1 KVM_FEATURE_CLOCKSOURCE_STABLE_BIT);
-static const uint32_t kvm_pv_eoi_features = (0x1 KVM_FEATURE_PV_EOI);
#else
static uint32_t kvm_default_features = 0;
-static const uint32_t kvm_pv_eoi_features = 0;
#endif
void enable_kvm_pv_eoi(void)
{
-kvm_default_features |= kvm_pv_eoi_features;
+if (kvm_enabled()) {
+kvm_default_features |= (1UL KVM_FEATURE_PV_EOI);
+}
}
void host_cpuid(uint32_t function, uint32_t count,
--
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Re: [PATCH qom-cpu 2/7] target-i386: Don't set any KVM flag by default if KVM is disabled
On Wed, Jan 09, 2013 at 09:41:37AM -0200, Eduardo Habkost wrote: [...] Andreas, please ignore this patch (it is not necessary anymore as this series doesn't include machine-type compatibility code for kvm_mmu). Patches 2-7 don't depend on this patch and should apply cleanly without it. I mean: patches 1 and 3-7 don't depend on this patch and can be applied cleanly without it. -- Eduardo -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH qom-cpu 2/7] target-i386: Don't set any KVM flag by default if KVM is disabled
On Wed, Jan 09, 2013 at 10:46:12AM +0100, Igor Mammedov wrote:
On Mon, 7 Jan 2013 16:20:43 -0200
Eduardo Habkost ehabk...@redhat.com wrote:
This is a cleanup that tries to solve two small issues:
- We don't need a separate kvm_pv_eoi_features variable just to keep a
constant calculated at compile-time, and this style would require
adding a separate variable (that's declared twice because of the
CONFIG_KVM ifdef) for each feature that's going to be enabled/disable
by machine-type compat code.
- The pc-1.3 code is setting the kvm_pv_eoi flag on cpuid_kvm_features
even when KVM is disabled at runtime. This small incosistency in
the cpuid_kvm_features field isn't a problem today because
cpuid_kvm_features is ignored by the TCG code, but it may cause
unexpected problems later when refactoring the CPUID handling code.
This patch eliminates the kvm_pv_eoi_features variable and simply uses
kvm_enabled() inside the enable_kvm_pv_eoi() compat function, so it
enables kvm_pv_eoi only if KVM is enabled. I believe this makes the
behavior of enable_kvm_pv_eoi() clearer and easier to understand.
Subj doesn't match what patch actually does.
Have you meant Don't set kvm_pv_eoi flag by default if KVM is disabled?
Although eliminate kvm_pv_eoi_features variable might better describe what
patch is doing.
True. The other flags in kvm_default_features may be already set and
will be copied to cpuid_kvm_features even if kvm_enabled() is false.
I had a previous version of this patch that also changed the code using
kvm_default_features to check kvm_enabled(), but I removed that part and
kept only the kvm_pv_eoi_features variable removal.
Andreas, please ignore this patch (it is not necessary anymore as this
series doesn't include machine-type compatibility code for kvm_mmu).
Patches 2-7 don't depend on this patch and should apply cleanly without
it.
I will send a new version later, probably with a separate patch to
ignore kvm_default_features if kvm_enabled() is false (so there's no
need to even check kvm_enabled() inside enable_kvm_pv_eoi()).
Signed-off-by: Eduardo Habkost ehabk...@redhat.com
---
Cc: kvm@vger.kernel.org
Cc: Michael S. Tsirkin m...@redhat.com
Cc: Gleb Natapov g...@redhat.com
Cc: Marcelo Tosatti mtosa...@redhat.com
Changes v2:
- Coding style fix
Changes v3:
- Eliminate #ifdef by using the fake KVM_FEATURE_PV_EOI #define
---
target-i386/cpu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 951e206..40400ac 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -164,15 +164,15 @@ static uint32_t kvm_default_features = (1
KVM_FEATURE_CLOCKSOURCE) | (1 KVM_FEATURE_ASYNC_PF) |
(1 KVM_FEATURE_STEAL_TIME) |
(1 KVM_FEATURE_CLOCKSOURCE_STABLE_BIT);
-static const uint32_t kvm_pv_eoi_features = (0x1 KVM_FEATURE_PV_EOI);
#else
static uint32_t kvm_default_features = 0;
-static const uint32_t kvm_pv_eoi_features = 0;
#endif
void enable_kvm_pv_eoi(void)
{
-kvm_default_features |= kvm_pv_eoi_features;
+if (kvm_enabled()) {
+kvm_default_features |= (1UL KVM_FEATURE_PV_EOI);
+}
}
void host_cpuid(uint32_t function, uint32_t count,
--
Eduardo
--
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