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[PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler

Philippe Mathieu-Daudé posted 65 patches 7 months, 1 week ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, Cameron Esfahani <dirty@apple.com>, Roman Bolshakov <rbolshakov@ddn.com>, Phil Dennis-Jordan <phil@philjordan.eu>, Mads Ynddal <mads@ynddal.dk>, Fabiano Rosas <farosas@suse.de>, Laurent Vivier <lvivier@redhat.com>, Stefano Stabellini <sstabellini@kernel.org>, Anthony PERARD <anthony@xenproject.org>, Paul Durrant <paul@xen.org>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Warner Losh <imp@bsdimp.com>, Kyle Evans <kevans@freebsd.org>, "Alex Bennée" <alex.bennee@linaro.org>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, "Dr. David Alan Gilbert" <dave@treblig.org>, Eduardo Habkost <eduardo@habkost.net>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Yanan Wang <wangyanan55@huawei.com>, Zhao Liu <zhao1.liu@intel.com>, Reinoud Zandijk <reinoud@netbsd.org>, Sunil Muthuswamy <sunilmut@microsoft.com>, Eric Blake <eblake@redhat.com>, Markus Armbruster <armbru@redhat.com>, Michael Roth <michael.roth@amd.com>, Peter Xu <peterx@redhat.com>, David Hildenbrand <david@redhat.com>, Peter Maydell <peter.maydell@linaro.org>, Alexander Graf <agraf@csgraf.de>
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[PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler
Posted by Philippe Mathieu-Daudé 7 months, 1 week ago 
In order to dispatch over AccelOpsClass::get_virtual_clock(),
we need it always defined, not calling a hidden handler under
the hood. Make AccelOpsClass::get_virtual_clock() mandatory.
Register the default cpus_kick_thread() for each accelerator.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 include/system/accel-ops.h        | 2 ++
 accel/hvf/hvf-accel-ops.c         | 1 +
 accel/kvm/kvm-accel-ops.c         | 1 +
 accel/tcg/tcg-accel-ops.c         | 2 ++
 accel/xen/xen-all.c               | 1 +
 system/cpus.c                     | 7 ++++---
 target/i386/nvmm/nvmm-accel-ops.c | 1 +
 target/i386/whpx/whpx-accel-ops.c | 1 +
 8 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/system/accel-ops.h b/include/system/accel-ops.h
index 8683cd37716..d5154acc75a 100644
--- a/include/system/accel-ops.h
+++ b/include/system/accel-ops.h
@@ -82,6 +82,8 @@ struct AccelOpsClass {
      * fetch time. The set function is needed if the accelerator wants
      * to track the changes to time as the timer is warped through
      * various timer events.
+     *
+     * get_virtual_clock() is mandatory.
      */
     int64_t (*get_virtual_clock)(void);
     void (*set_virtual_clock)(int64_t time);
diff --git a/accel/hvf/hvf-accel-ops.c b/accel/hvf/hvf-accel-ops.c
index 17776e700eb..cf623a1ea47 100644
--- a/accel/hvf/hvf-accel-ops.c
+++ b/accel/hvf/hvf-accel-ops.c
@@ -369,6 +369,7 @@ static void hvf_accel_ops_class_init(ObjectClass *oc, const void *data)
     ops->update_guest_debug = hvf_update_guest_debug;
 
     ops->get_elapsed_ticks = cpu_get_ticks;
+    ops->get_virtual_clock = cpu_get_clock;
     ops->get_vcpu_stats = hvf_get_vcpu_stats;
 };
 
diff --git a/accel/kvm/kvm-accel-ops.c b/accel/kvm/kvm-accel-ops.c
index f27228d4cd9..dde498e0626 100644
--- a/accel/kvm/kvm-accel-ops.c
+++ b/accel/kvm/kvm-accel-ops.c
@@ -97,6 +97,7 @@ static void kvm_accel_ops_class_init(ObjectClass *oc, const void *data)
 #endif
 
     ops->get_elapsed_ticks = cpu_get_ticks;
+    ops->get_virtual_clock = cpu_get_clock;
 }
 
 static const TypeInfo kvm_accel_ops_type = {
diff --git a/accel/tcg/tcg-accel-ops.c b/accel/tcg/tcg-accel-ops.c
index f22f5d73abe..780e9debbc4 100644
--- a/accel/tcg/tcg-accel-ops.c
+++ b/accel/tcg/tcg-accel-ops.c
@@ -207,6 +207,7 @@ static void tcg_accel_ops_init(AccelClass *ac)
         ops->kick_vcpu_thread = mttcg_kick_vcpu_thread;
         ops->handle_interrupt = tcg_handle_interrupt;
         ops->get_elapsed_ticks = cpu_get_ticks;
+        ops->get_virtual_clock = cpu_get_clock;
     } else {
         ops->create_vcpu_thread = rr_start_vcpu_thread;
         ops->kick_vcpu_thread = rr_kick_vcpu_thread;
@@ -217,6 +218,7 @@ static void tcg_accel_ops_init(AccelClass *ac)
             ops->get_elapsed_ticks = icount_get;
         } else {
             ops->handle_interrupt = tcg_handle_interrupt;
+            ops->get_virtual_clock = cpu_get_clock;
             ops->get_elapsed_ticks = cpu_get_ticks;
         }
     }
diff --git a/accel/xen/xen-all.c b/accel/xen/xen-all.c
index 48d458bc4c7..85fb9d1606c 100644
--- a/accel/xen/xen-all.c
+++ b/accel/xen/xen-all.c
@@ -158,6 +158,7 @@ static void xen_accel_ops_class_init(ObjectClass *oc, const void *data)
     ops->kick_vcpu_thread = cpus_kick_thread;
     ops->handle_interrupt = generic_handle_interrupt;
     ops->get_elapsed_ticks = cpu_get_ticks;
+    ops->get_virtual_clock = cpu_get_clock;
 }
 
 static const TypeInfo xen_accel_ops_type = {
diff --git a/system/cpus.c b/system/cpus.c
index d32b89ecf7b..6c99756346a 100644
--- a/system/cpus.c
+++ b/system/cpus.c
@@ -216,10 +216,10 @@ int64_t cpus_get_virtual_clock(void)
      *
      * XXX
      */
-    if (cpus_accel && cpus_accel->get_virtual_clock) {
-        return cpus_accel->get_virtual_clock();
+    if (!cpus_accel) {
+        return cpu_get_clock();
     }
-    return cpu_get_clock();
+    return cpus_accel->get_virtual_clock();
 }
 
 /*
@@ -666,6 +666,7 @@ void cpus_register_accel(const AccelOpsClass *ops)
     assert(ops->kick_vcpu_thread);
     assert(ops->handle_interrupt);
     assert(ops->get_elapsed_ticks);
+    assert(ops->get_virtual_clock);
     cpus_accel = ops;
 }
 
diff --git a/target/i386/nvmm/nvmm-accel-ops.c b/target/i386/nvmm/nvmm-accel-ops.c
index 4deff57471c..a2e84cb087a 100644
--- a/target/i386/nvmm/nvmm-accel-ops.c
+++ b/target/i386/nvmm/nvmm-accel-ops.c
@@ -86,6 +86,7 @@ static void nvmm_accel_ops_class_init(ObjectClass *oc, const void *data)
     ops->synchronize_pre_loadvm = nvmm_cpu_synchronize_pre_loadvm;
 
     ops->get_elapsed_ticks = cpu_get_ticks;
+    ops->get_virtual_clock = cpu_get_clock;
 }
 
 static const TypeInfo nvmm_accel_ops_type = {
diff --git a/target/i386/whpx/whpx-accel-ops.c b/target/i386/whpx/whpx-accel-ops.c
index f47033a502c..d27e89dd9c5 100644
--- a/target/i386/whpx/whpx-accel-ops.c
+++ b/target/i386/whpx/whpx-accel-ops.c
@@ -89,6 +89,7 @@ static void whpx_accel_ops_class_init(ObjectClass *oc, const void *data)
     ops->synchronize_pre_loadvm = whpx_cpu_synchronize_pre_loadvm;
 
     ops->get_elapsed_ticks = cpu_get_ticks;
+    ops->get_virtual_clock = cpu_get_clock;
 }
 
 static const TypeInfo whpx_accel_ops_type = {
-- 
2.49.0
Re: [PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler
Posted by Mads Ynddal 7 months, 1 week ago 
> On 2 Jul 2025, at 20.53, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
> 
> In order to dispatch over AccelOpsClass::get_virtual_clock(),
> we need it always defined, not calling a hidden handler under
> the hood. Make AccelOpsClass::get_virtual_clock() mandatory.
> Register the default cpus_kick_thread() for each accelerator.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> include/system/accel-ops.h        | 2 ++
> accel/hvf/hvf-accel-ops.c         | 1 +
> accel/kvm/kvm-accel-ops.c         | 1 +
> accel/tcg/tcg-accel-ops.c         | 2 ++
> accel/xen/xen-all.c               | 1 +
> system/cpus.c                     | 7 ++++---
> target/i386/nvmm/nvmm-accel-ops.c | 1 +
> target/i386/whpx/whpx-accel-ops.c | 1 +
> 8 files changed, 13 insertions(+), 3 deletions(-)

Reviewed-by: Mads Ynddal <mads@ynddal.dk>
Re: [PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler
Posted by Zhao Liu 7 months, 1 week ago 
On Wed, Jul 02, 2025 at 08:53:21PM +0200, Philippe Mathieu-Daudé wrote:
> Date: Wed,  2 Jul 2025 20:53:21 +0200
> From: Philippe Mathieu-Daudé <philmd@linaro.org>
> Subject: [PATCH v4 59/65] accel: Always register
>  AccelOpsClass::get_virtual_clock() handler
> X-Mailer: git-send-email 2.49.0
> 
> In order to dispatch over AccelOpsClass::get_virtual_clock(),
> we need it always defined, not calling a hidden handler under
> the hood. Make AccelOpsClass::get_virtual_clock() mandatory.
> Register the default cpus_kick_thread() for each accelerator.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>  include/system/accel-ops.h        | 2 ++
>  accel/hvf/hvf-accel-ops.c         | 1 +
>  accel/kvm/kvm-accel-ops.c         | 1 +
>  accel/tcg/tcg-accel-ops.c         | 2 ++
>  accel/xen/xen-all.c               | 1 +
>  system/cpus.c                     | 7 ++++---
>  target/i386/nvmm/nvmm-accel-ops.c | 1 +
>  target/i386/whpx/whpx-accel-ops.c | 1 +
>  8 files changed, 13 insertions(+), 3 deletions(-)

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Re: [PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler
Posted by Pierrick Bouvier 7 months, 1 week ago 
On 7/2/25 11:53 AM, Philippe Mathieu-Daudé wrote:
> In order to dispatch over AccelOpsClass::get_virtual_clock(),
> we need it always defined, not calling a hidden handler under
> the hood. Make AccelOpsClass::get_virtual_clock() mandatory.
> Register the default cpus_kick_thread() for each accelerator.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/system/accel-ops.h        | 2 ++
>   accel/hvf/hvf-accel-ops.c         | 1 +
>   accel/kvm/kvm-accel-ops.c         | 1 +
>   accel/tcg/tcg-accel-ops.c         | 2 ++
>   accel/xen/xen-all.c               | 1 +
>   system/cpus.c                     | 7 ++++---
>   target/i386/nvmm/nvmm-accel-ops.c | 1 +
>   target/i386/whpx/whpx-accel-ops.c | 1 +
>   8 files changed, 13 insertions(+), 3 deletions(-)

Seeing the pattern in last 3 commits, I have a question regarding QOM.
Is that possible to get a constructor called for parent type 
(TYPE_ACCEL_OPS), where all default values would be set, and so every 
child class (specialized accelerator) would just need to override the 
field they want with their own method?

It would be more easy than explicitely setting default values in all sub 
classes, but maybe QOM design is limited to that.
Re: [PATCH v4 59/65] accel: Always register AccelOpsClass::get_virtual_clock() handler
Posted by Pierrick Bouvier 7 months, 1 week ago 
On 7/2/25 11:53 AM, Philippe Mathieu-Daudé wrote:
> In order to dispatch over AccelOpsClass::get_virtual_clock(),
> we need it always defined, not calling a hidden handler under
> the hood. Make AccelOpsClass::get_virtual_clock() mandatory.
> Register the default cpus_kick_thread() for each accelerator.

Same same.

>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/system/accel-ops.h        | 2 ++
>   accel/hvf/hvf-accel-ops.c         | 1 +
>   accel/kvm/kvm-accel-ops.c         | 1 +
>   accel/tcg/tcg-accel-ops.c         | 2 ++
>   accel/xen/xen-all.c               | 1 +
>   system/cpus.c                     | 7 ++++---
>   target/i386/nvmm/nvmm-accel-ops.c | 1 +
>   target/i386/whpx/whpx-accel-ops.c | 1 +
>   8 files changed, 13 insertions(+), 3 deletions(-)

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

Patchew 2.1-devel-b67e4c2

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