[Qemu-devel] [PATCH v8 2/6] Wrapper function to wait on condition for the main loop mutex

Aravinda Prasad posted 6 patches 6 years, 6 months 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There is a newer version of this series
[Qemu-devel] [PATCH v8 2/6] Wrapper function to wait on condition for the main loop mutex
Posted by Aravinda Prasad 6 years, 6 months ago
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 <aravinda@linux.vnet.ibm.com>
---
 cpus.c                   |    5 +++++
 include/qemu/main-loop.h |    8 ++++++++
 2 files changed, 13 insertions(+)

diff --git a/cpus.c b/cpus.c
index e83f72b..d9379e7 100644
--- a/cpus.c
+++ b/cpus.c
@@ -1858,6 +1858,11 @@ 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 f6ba78e..a6d20b0 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: [Qemu-devel] [PATCH v8 2/6] Wrapper function to wait on condition for the main loop mutex
Posted by David Gibson 6 years, 6 months ago
On Mon, Apr 22, 2019 at 12:33:07PM +0530, Aravinda Prasad wrote:
> 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 <aravinda@linux.vnet.ibm.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  cpus.c                   |    5 +++++
>  include/qemu/main-loop.h |    8 ++++++++
>  2 files changed, 13 insertions(+)
> 
> diff --git a/cpus.c b/cpus.c
> index e83f72b..d9379e7 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1858,6 +1858,11 @@ 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 f6ba78e..a6d20b0 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);
> 

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson
Re: [Qemu-devel] [Qemu-ppc] [PATCH v8 2/6] Wrapper function to wait on condition for the main loop mutex
Posted by Greg Kurz 6 years, 6 months ago
On Mon, 22 Apr 2019 12:33:07 +0530
Aravinda Prasad <aravinda@linux.vnet.ibm.com> wrote:

> 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 <aravinda@linux.vnet.ibm.com>
> ---

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 e83f72b..d9379e7 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1858,6 +1858,11 @@ 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 f6ba78e..a6d20b0 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);
> 
>