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[Qemu-devel] [RFC 01/48] cpu: introduce run_on_cpu_no_bql

Emilio G. Cota posted 48 patches 7 years ago
There is a newer version of this series
[Qemu-devel] [RFC 01/48] cpu: introduce run_on_cpu_no_bql
Posted by Emilio G. Cota 7 years ago 
This allows us to queue synchronous CPU work without the BQL.

Will gain a user soon.

Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 include/qom/cpu.h | 13 +++++++++++++
 cpus-common.c     | 28 ++++++++++++++++++++++------
 2 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index 204bc94056..863aa2bff1 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -877,6 +877,19 @@ bool cpu_is_stopped(CPUState *cpu);
  */
 void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data);
 
+/**
+ * run_on_cpu_no_bql
+ * @cpu: The vCPU to run on.
+ * @func: The function to be executed.
+ * @data: Data to pass to the function.
+ *
+ * Schedules the function @func for execution on the vCPU @cpu.
+ * This function is run outside the BQL.
+ * See also: run_on_cpu()
+ */
+void run_on_cpu_no_bql(CPUState *cpu, run_on_cpu_func func,
+                       run_on_cpu_data data);
+
 /**
  * async_run_on_cpu:
  * @cpu: The vCPU to run on.
diff --git a/cpus-common.c b/cpus-common.c
index cffb2b71ac..b478fc8741 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -144,7 +144,8 @@ static void queue_work_on_cpu(CPUState *cpu, struct qemu_work_item *wi)
     cpu_mutex_unlock(cpu);
 }
 
-void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
+static void do_run_on_cpu(CPUState *cpu, run_on_cpu_func func,
+                          run_on_cpu_data data, bool bql)
 {
     struct qemu_work_item wi;
     bool has_bql = qemu_mutex_iothread_locked();
@@ -152,12 +153,16 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
     g_assert(no_cpu_mutex_locked());
 
     if (qemu_cpu_is_self(cpu)) {
-        if (has_bql) {
-            func(cpu, data);
+        if (bql) {
+            if (has_bql) {
+                func(cpu, data);
+            } else {
+                qemu_mutex_lock_iothread();
+                func(cpu, data);
+                qemu_mutex_unlock_iothread();
+            }
         } else {
-            qemu_mutex_lock_iothread();
             func(cpu, data);
-            qemu_mutex_unlock_iothread();
         }
         return;
     }
@@ -172,7 +177,7 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
     wi.done = false;
     wi.free = false;
     wi.exclusive = false;
-    wi.bql = true;
+    wi.bql = bql;
 
     cpu_mutex_lock(cpu);
     queue_work_on_cpu_locked(cpu, &wi);
@@ -189,6 +194,17 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
     }
 }
 
+void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
+{
+    do_run_on_cpu(cpu, func, data, true);
+}
+
+void
+run_on_cpu_no_bql(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
+{
+    do_run_on_cpu(cpu, func, data, false);
+}
+
 void async_run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
 {
     struct qemu_work_item *wi;
-- 
2.17.1
Re: [Qemu-devel] [RFC 01/48] cpu: introduce run_on_cpu_no_bql
Posted by Alex Bennée 6 years, 11 months ago 
Emilio G. Cota <cota@braap.org> writes:

> This allows us to queue synchronous CPU work without the BQL.
>
> Will gain a user soon.

This is also in the cpu-lock series right?

>
> Signed-off-by: Emilio G. Cota <cota@braap.org>
> ---
>  include/qom/cpu.h | 13 +++++++++++++
>  cpus-common.c     | 28 ++++++++++++++++++++++------
>  2 files changed, 35 insertions(+), 6 deletions(-)
>
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 204bc94056..863aa2bff1 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -877,6 +877,19 @@ bool cpu_is_stopped(CPUState *cpu);
>   */
>  void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data);
>
> +/**
> + * run_on_cpu_no_bql
> + * @cpu: The vCPU to run on.
> + * @func: The function to be executed.
> + * @data: Data to pass to the function.
> + *
> + * Schedules the function @func for execution on the vCPU @cpu.
> + * This function is run outside the BQL.
> + * See also: run_on_cpu()
> + */
> +void run_on_cpu_no_bql(CPUState *cpu, run_on_cpu_func func,
> +                       run_on_cpu_data data);
> +
>  /**
>   * async_run_on_cpu:
>   * @cpu: The vCPU to run on.
> diff --git a/cpus-common.c b/cpus-common.c
> index cffb2b71ac..b478fc8741 100644
> --- a/cpus-common.c
> +++ b/cpus-common.c
> @@ -144,7 +144,8 @@ static void queue_work_on_cpu(CPUState *cpu, struct qemu_work_item *wi)
>      cpu_mutex_unlock(cpu);
>  }
>
> -void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
> +static void do_run_on_cpu(CPUState *cpu, run_on_cpu_func func,
> +                          run_on_cpu_data data, bool bql)
>  {
>      struct qemu_work_item wi;
>      bool has_bql = qemu_mutex_iothread_locked();
> @@ -152,12 +153,16 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
>      g_assert(no_cpu_mutex_locked());
>
>      if (qemu_cpu_is_self(cpu)) {
> -        if (has_bql) {
> -            func(cpu, data);
> +        if (bql) {
> +            if (has_bql) {
> +                func(cpu, data);
> +            } else {
> +                qemu_mutex_lock_iothread();
> +                func(cpu, data);
> +                qemu_mutex_unlock_iothread();
> +            }
>          } else {
> -            qemu_mutex_lock_iothread();
>              func(cpu, data);
> -            qemu_mutex_unlock_iothread();
>          }
>          return;
>      }
> @@ -172,7 +177,7 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
>      wi.done = false;
>      wi.free = false;
>      wi.exclusive = false;
> -    wi.bql = true;
> +    wi.bql = bql;
>
>      cpu_mutex_lock(cpu);
>      queue_work_on_cpu_locked(cpu, &wi);
> @@ -189,6 +194,17 @@ void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
>      }
>  }
>
> +void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
> +{
> +    do_run_on_cpu(cpu, func, data, true);
> +}
> +
> +void
> +run_on_cpu_no_bql(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
> +{
> +    do_run_on_cpu(cpu, func, data, false);
> +}
> +
>  void async_run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
>  {
>      struct qemu_work_item *wi;


--
Alex Bennée
Re: [Qemu-devel] [RFC 01/48] cpu: introduce run_on_cpu_no_bql
Posted by Emilio G. Cota 6 years, 11 months ago 
On Wed, Nov 14, 2018 at 11:30:19 +0000, Alex Bennée wrote:
> 
> Emilio G. Cota <cota@braap.org> writes:
> 
> > This allows us to queue synchronous CPU work without the BQL.
> >
> > Will gain a user soon.
> 
> This is also in the cpu-lock series right?

No, in the cpu-lock series we add async_run_on_cpu_no_bql;
here we add the sync version.

		E.
Re: [Qemu-devel] [RFC 01/48] cpu: introduce run_on_cpu_no_bql
Posted by Alex Bennée 6 years, 11 months ago 
Emilio G. Cota <cota@braap.org> writes:

> On Wed, Nov 14, 2018 at 11:30:19 +0000, Alex Bennée wrote:
>>
>> Emilio G. Cota <cota@braap.org> writes:
>>
>> > This allows us to queue synchronous CPU work without the BQL.
>> >
>> > Will gain a user soon.
>>
>> This is also in the cpu-lock series right?
>
> No, in the cpu-lock series we add async_run_on_cpu_no_bql;
> here we add the sync version.

My mistake, being word blind:

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

--
Alex Bennée

Patchew 2.1-devel-b67e4c2

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