[PATCH v18 1/7] Wrapper function to wait on condition for the main loop mutex

Ganesh Goudar posted 7 patches 6 years, 1 month ago
Maintainers: Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>, David Gibson <david@gibson.dropbear.id.au>
There is a newer version of this series
[PATCH v18 1/7] Wrapper function to wait on condition for the main loop mutex
Posted by Ganesh Goudar 6 years, 1 month ago
From: Aravinda Prasad <arawinda.p@gmail.com>

Introduce a wrapper function to wait on condition for
the main loop mutex. This function atomically releases
the main loop mutex and causes the calling thread to
block on the condition. This wrapper is required because
qemu_global_mutex is a static variable.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
---
 cpus.c                   | 5 +++++
 include/qemu/main-loop.h | 8 ++++++++
 2 files changed, 13 insertions(+)

diff --git a/cpus.c b/cpus.c
index b472378b70..79388d2b0f 100644
--- a/cpus.c
+++ b/cpus.c
@@ -1835,6 +1835,11 @@ void qemu_mutex_unlock_iothread(void)
     qemu_mutex_unlock(&qemu_global_mutex);
 }
 
+void qemu_cond_wait_iothread(QemuCond *cond)
+{
+    qemu_cond_wait(cond, &qemu_global_mutex);
+}
+
 static bool all_vcpus_paused(void)
 {
     CPUState *cpu;
diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h
index f6ba78ea73..a6d20b0719 100644
--- a/include/qemu/main-loop.h
+++ b/include/qemu/main-loop.h
@@ -295,6 +295,14 @@ void qemu_mutex_lock_iothread_impl(const char *file, int line);
  */
 void qemu_mutex_unlock_iothread(void);
 
+/*
+ * qemu_cond_wait_iothread: Wait on condition for the main loop mutex
+ *
+ * This function atomically releases the main loop mutex and causes
+ * the calling thread to block on the condition.
+ */
+void qemu_cond_wait_iothread(QemuCond *cond);
+
 /* internal interfaces */
 
 void qemu_fd_register(int fd);
-- 
2.17.2


Re: [PATCH v18 1/7] Wrapper function to wait on condition for the main loop mutex
Posted by Greg Kurz 6 years, 1 month ago
On Thu,  2 Jan 2020 13:21:05 +0530
Ganesh Goudar <ganeshgr@linux.ibm.com> wrote:

> From: Aravinda Prasad <arawinda.p@gmail.com>
> 
> Introduce a wrapper function to wait on condition for
> the main loop mutex. This function atomically releases
> the main loop mutex and causes the calling thread to
> block on the condition. This wrapper is required because
> qemu_global_mutex is a static variable.
> 
> Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> Reviewed-by: Greg Kurz <groug@kaod.org>
> ---

This should have your Signed-off-by: tag as well.

>  cpus.c                   | 5 +++++
>  include/qemu/main-loop.h | 8 ++++++++
>  2 files changed, 13 insertions(+)
> 
> diff --git a/cpus.c b/cpus.c
> index b472378b70..79388d2b0f 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1835,6 +1835,11 @@ void qemu_mutex_unlock_iothread(void)
>      qemu_mutex_unlock(&qemu_global_mutex);
>  }
>  
> +void qemu_cond_wait_iothread(QemuCond *cond)
> +{
> +    qemu_cond_wait(cond, &qemu_global_mutex);
> +}
> +
>  static bool all_vcpus_paused(void)
>  {
>      CPUState *cpu;
> diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h
> index f6ba78ea73..a6d20b0719 100644
> --- a/include/qemu/main-loop.h
> +++ b/include/qemu/main-loop.h
> @@ -295,6 +295,14 @@ void qemu_mutex_lock_iothread_impl(const char *file, int line);
>   */
>  void qemu_mutex_unlock_iothread(void);
>  
> +/*
> + * qemu_cond_wait_iothread: Wait on condition for the main loop mutex
> + *
> + * This function atomically releases the main loop mutex and causes
> + * the calling thread to block on the condition.
> + */
> +void qemu_cond_wait_iothread(QemuCond *cond);
> +
>  /* internal interfaces */
>  
>  void qemu_fd_register(int fd);


Re: [PATCH v18 1/7] Wrapper function to wait on condition for the main loop mutex
Posted by Ganesh 6 years, 1 month ago
On 1/5/20 8:47 PM, Greg Kurz wrote:
> On Thu,  2 Jan 2020 13:21:05 +0530
> Ganesh Goudar <ganeshgr@linux.ibm.com> wrote:
>
>> From: Aravinda Prasad <arawinda.p@gmail.com>
>>
>> Introduce a wrapper function to wait on condition for
>> the main loop mutex. This function atomically releases
>> the main loop mutex and causes the calling thread to
>> block on the condition. This wrapper is required because
>> qemu_global_mutex is a static variable.
>>
>> Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
>> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
>> Reviewed-by: Greg Kurz <groug@kaod.org>
>> ---
> This should have your Signed-off-by: tag as well.
Sure, thanks
>
>>   cpus.c                   | 5 +++++
>>   include/qemu/main-loop.h | 8 ++++++++
>>   2 files changed, 13 insertions(+)
>>
>> diff --git a/cpus.c b/cpus.c
>> index b472378b70..79388d2b0f 100644
>> --- a/cpus.c
>> +++ b/cpus.c
>> @@ -1835,6 +1835,11 @@ void qemu_mutex_unlock_iothread(void)
>>       qemu_mutex_unlock(&qemu_global_mutex);
>>   }
>>   
>> +void qemu_cond_wait_iothread(QemuCond *cond)
>> +{
>> +    qemu_cond_wait(cond, &qemu_global_mutex);
>> +}
>> +
>>   static bool all_vcpus_paused(void)
>>   {
>>       CPUState *cpu;
>> diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h
>> index f6ba78ea73..a6d20b0719 100644
>> --- a/include/qemu/main-loop.h
>> +++ b/include/qemu/main-loop.h
>> @@ -295,6 +295,14 @@ void qemu_mutex_lock_iothread_impl(const char *file, int line);
>>    */
>>   void qemu_mutex_unlock_iothread(void);
>>   
>> +/*
>> + * qemu_cond_wait_iothread: Wait on condition for the main loop mutex
>> + *
>> + * This function atomically releases the main loop mutex and causes
>> + * the calling thread to block on the condition.
>> + */
>> +void qemu_cond_wait_iothread(QemuCond *cond);
>> +
>>   /* internal interfaces */
>>   
>>   void qemu_fd_register(int fd);